In modern engineering manufacturing, where tolerances are tightening and material diversity is expanding, this cutting method has become a precision benchmark.

Industry data shows that non-thermal cutting processes can reduce secondary finishing operations by more than 30 percent in precision-focused manufacturing environments.

That efficiency matters as engineers increasingly work with composites, hardened alloys, and multi-material assemblies that are poorly heat-resistant.

Material precision is not just about hitting nominal dimensions.

It is about edge integrity, repeatability, structural stability, and predictable performance once parts move into assembly or service.

This article explores how advanced waterjet cutting works, why it delivers such high precision, how it compares to alternative cutting technologies, and where it fits best in modern engineering manufacturing workflows.

What Is Advanced Waterjet Cutting and Why Does It Matter for Precision Manufacturing?

Advanced waterjet cutting is a machining method that removes material through controlled erosion using a focused stream of pressurized water, with or without abrasive media.

It matters for precision manufacturing because it cuts without introducing heat, mechanical stress, or microstructural changes to the material.

Unlike thermal or mechanical cutting methods, waterjet cutting preserves the original material properties.

That preservation directly translates into tighter dimensional accuracy and improved consistency across production runs.

For engineers, this means fewer unpredictable variables.

Parts come off the table closer to the final specification, which reduces rework, scrap rates, and downstream inspection failures.

As manufacturing shifts toward complex geometries and mixed materials, waterjet cutting provides a stable, predictable process window that supports precision rather than fighting against it.

How Does Waterjet Cutting Work at an Engineering Level?

The waterjet cutting process is a controlled material removal technique that converts hydraulic energy into a high-velocity cutting stream capable of eroding solid materials.

In engineering manufacturing, the process is valued for its predictable physics and scalable precision.

Water is pressurized up to 90,000 psi and directed through a precision orifice, creating a coherent jet with extreme kinetic energy.

For harder materials, abrasive particles such as garnet are introduced into the stream, enabling efficient cutting of metals, ceramics, and composites.

The cutting action occurs through micro-scale erosion rather than melting or shearing.

That distinction is critical because it eliminates thermal gradients and residual stresses.

The main stages of the waterjet cutting process include five distinct steps.

1. Pressurizing water to ultra-high levels using an intensifier or direct-drive pump
2. Forming a focused jet through a diamond, sapphire, orifice
3. Introducing abrasive media when cutting dense or complex materials
4. Guiding the jet along programmed toolpaths using CNC control
5. Dissipating energy safely in a catcher tank after material separation

Each stage contributes directly to the final dimensional accuracy of the cut part.

What Makes Waterjet Cutting a High-Precision Manufacturing Technology?

Advanced waterjet cutting is a manufacturing technology that achieves precision through controlled erosion, stable energy delivery, and digital motion control.

Its ability to maintain accuracy across thickness variations and material types sets it apart in engineering applications.

Because the process is cold, the cut geometry remains true to the programmed path.

There is no thermal expansion, no warping, and no recast layer along the edge.

Modern systems integrate CNC motion platforms, taper compensation software, and closed-loop pressure control.

Together, these elements allow engineers to hold tight tolerances even on thick or layered materials.

Precision in waterjet cutting is not accidental.

It is engineered through system stability, software intelligence, and material-specific parameter control.

Cold Cutting and Its Impact on Dimensional Accuracy

Cold cutting is a material removal approach that avoids heat generation entirely during the cutting process.

In waterjet cutting, cold cutting preserves the material’s original mechanical and chemical properties.

When heat is introduced, materials expand, soften, or harden unevenly.

Waterjet cutting avoids these effects, which allows parts to remain dimensionally stable throughout and after cutting.

This stability is essential in aerospace alloys, hardened steels, and laminated composites.

Dimensional accuracy remains consistent from the first cut to the last.

For engineers, cold cutting simplifies tolerance planning and reduces the need for post-processing corrections.

Kerf Width Control and Edge Finish Consistency

Kerf width control is the ability to maintain a consistent cut width along the entire toolpath.

In waterjet cutting, kerf control directly influences part accuracy and edge quality.

Advanced systems regulate pressure, abrasive flow rate, and traverse speed to stabilize the cutting stream.

This stability minimizes kerf variation, even when cutting complex geometries or variable thicknesses.

Consistent edge finish reduces the need for secondary grinding or machining.

It also improves fit-up accuracy during assembly.

Precision edge control is one reason advanced waterjets are often selected for tight-tolerance engineering components.

What Are the Main Types of Waterjet Cutting Systems Used in Engineering Manufacturing?

Waterjet cutting systems fall into two primary categories based on how the cutting energy is applied.

Each type serves different precision and material requirements within engineering manufacturing.

The choice between systems depends on material hardness, thickness, and surface finish expectations.

Understanding the differences helps engineers select the right tool for the job.

Pure Waterjet Cutting Systems

Pure waterjet cutting systems use only pressurized water without abrasive additives.

They are primarily used for softer materials that require precision without excessive cutting force.

Typical applications include polymers, rubber, foam, textiles, and certain food-grade materials.

The cutting action is clean, precise, and free from contamination.

Pure waterjet systems excel in applications where edge integrity and material cleanliness are critical.

They also offer lower operating costs compared to abrasive systems.

Abrasive Waterjet Cutting Systems

Abrasive waterjet cutting systems introduce hard mineral particles into the water stream to cut dense materials.

These machines are the backbone of precision engineering manufacturing.

They can cut steel, aluminum, titanium, glass, stone, ceramics, and composites.

The abrasive particles perform the erosion while water acts as the energy carrier.

Modern abrasive systems, such as precision waterjet cutting machines, combine CNC motion control with stable pressure delivery to maintain accuracy across complex parts.

These systems enable engineers to achieve tight tolerances without sacrificing material integrity.

What Materials Benefit Most from Precision Waterjet Cutting?

Waterjet cutting supports a wide range of engineering materials with minimal process-induced distortion.

Some material groups are more sensitive to heat or mechanical stress than others.

The six material categories that gain the most precision advantages include:

1. Metals such as steel, aluminum, and titanium, where thermal distortion must be avoided
2. Composites like carbon fiber and fiberglass that delaminate under heat
3. Ceramics and glass that crack under mechanical cutting forces
4. Laminated materials with dissimilar layers and expansion rates
5. Stone and engineered surfaces requiring clean, chip-free edges
6. Plastics that melt or deform under laser or plasma cutting

This versatility makes waterjet cutting a universal precision tool.

What Are the Key Advantages of Advanced Waterjet Cutting for Material Precision?

Advanced waterjet cutting delivers several precision-related advantages that directly impact manufacturing quality.

These advantages extend beyond dimensional accuracy alone.

There are exactly seven primary benefits.

1. Preserves material properties by eliminating heat input
2. Maintains tight tolerances across varying thicknesses
3. Produces clean edges with minimal secondary finishing
4. Cuts virtually any material without a tool change
5. Supports complex geometries and internal features
6. Reduces fixturing stress due to low cutting forces
7. Enables consistent results in low-volume and high-mix production

Each benefit contributes to predictable, repeatable manufacturing outcomes.

What Are the Limitations of Waterjet Cutting in Precision Engineering Applications?

Waterjet cutting is exact, but it is not without limitations.

Understanding these constraints helps engineers apply the technology appropriately.

There are precisely five notable limitations.

1. Increases operating costs due to abrasive consumption
2. Limits cutting speed compared to some thermal methods
3. Requires careful control to prevent taper on thick materials
4. Generates slurry waste that must be managed
5. May struggle with excellent micro-scale features

Despite these drawbacks, many precision applications still favor waterjet cutting for its ability to maintain material integrity.

How Does Waterjet Cutting Compare to Laser and Plasma Cutting for Precision Manufacturing?

Waterjet cutting, laser cutting, and plasma cutting differ fundamentally in how they remove material.

Waterjet cutting provides superior material preservation, while laser and plasma excel in speed for thin metals.

Laser cutting introduces heat, which can affect microstructure and tolerances.

Plasma cutting introduces even more thermal distortion and wider kerfs.

Waterjet cutting avoids both issues but operates at slower speeds and higher consumable costs.

The trade-off is improved accuracy, edge quality, and material flexibility.

A comparison table would typically evaluate heat input, material range, tolerances, edge finish, and operating cost to clarify these differences.

What Engineering Applications Rely on Waterjet Cutting for High Precision?

Waterjet cutting supports a broad range of engineering applications where accuracy and material integrity are critical.

Its adoption spans multiple industries.

There are precisely six major application areas.

1. Aerospace component manufacturing
2. Automotive prototyping and low-volume production
3. Architectural and structural fabrication
4. Electronics and enclosure manufacturing
5. Medical device component cutting
6. Research and experimental engineering projects

In laboratory and research environments, precision surface preparation and component fabrication are often paired with advanced cleaning methods such as industrial laser cleaning machines to maintain contamination-free surfaces before assembly or testing.

What Are the Most Important Parameters That Influence Waterjet Cutting Precision?

Precision in waterjet cutting depends on controlling multiple interrelated parameters.

Each parameter affects kerf quality, accuracy, and repeatability.

The seven most critical parameters include:

1. Water pressure stability
2. Abrasive type and grain size
3. Abrasive flow rate
4. Cutting speed and acceleration
5. Nozzle condition and alignment
6. Stand-off distance
7. CNC motion accuracy

Fine-tuning these variables allows engineers to optimize precision for each material.

What Tolerances Can Advanced Waterjet Cutting Achieve?

Advanced waterjet cutting can achieve tolerances as tight as ±0.05 mm for thin materials under controlled conditions.

Tolerance capability decreases gradually as material thickness increases.

For thin materials up to 1 mm, tolerances typically range from ±0.1 mm to ±0.2 mm.

For medium thickness materials between 1 mm and 5 mm, tolerances range from ±0.2 mm to ±0.5 mm.

For materials over 5 mm thick, tolerances are usually ±0.5 mm to ±1.0 mm, or approximately ±0.020 to ±0.040 inches.

How to Use Waterjet Cutting to Maximize Material Precision

Maximizing precision with waterjet cutting involves a structured process from design through execution.

There are precisely five main steps involved.

1. Material selection and characterization
2. Design optimization for waterjet behavior
3. Parameter calibration and testing
4. Controlled cutting execution
5. Post-cut inspection and verification

Each step builds on the previous one to ensure predictable outcomes.

Material Preparation and Design Optimization

Material preparation is the process of selecting and configuring raw stock for accurate cutting.

Design optimization ensures features align with waterjet capabilities.

Engineers must account for kerf width, taper compensation, and minimum feature sizes.

Proper nesting reduces distortion and improves efficiency.

Good preparation directly improves final dimensional accuracy.

Machine Setup and Parameter Calibration

Machine setup is the process of configuring pressure, abrasive flow, and motion parameters.

Calibration ensures the system delivers consistent energy throughout the cut.

Trial cuts and test coupons help validate settings before production.

This step is critical for achieving repeatable precision.

How Much Does Precision Waterjet Cutting Cost in Engineering Manufacturing?

Precision waterjet cutting typically costs between 250 per hour in the United States.

Pricing varies based on material, thickness, and complexity.

There are precisely six cost factors.

1. Machine time
2. Abrasive consumption
3. Material type
4. Thickness and cutting speed
5. Programming complexity
6. Post-processing requirements

Understanding these factors helps engineers balance cost and precision.

What Should Engineers Look for in a High-Precision Waterjet Cutting System?

A high-precision waterjet system is defined by stability, control, and long-term accuracy.

Engineers should evaluate systems beyond headline pressure ratings.

Key indicators include motion accuracy, software compensation features, pump reliability, and service support.

Precision is sustained through consistency, not peak performance alone.

Conclusion: Why Waterjet Cutting Is a Precision Benchmark in Engineering Manufacturing

Advanced waterjet cutting has earned its role as a precision benchmark by combining material versatility with predictable accuracy.

Its cold cutting nature preserves material properties while enabling complex geometries and tight tolerances.

As engineering manufacturing continues to demand higher precision across a broader range of materials, waterjet technology remains a reliable solution.

When applied correctly, it delivers accuracy, consistency, and confidence from design to final part.

Hassan Ahmed

Hassan graduated with a Master’s degree in Chemical Engineering from the University of Chester (UK). He currently works as a design engineering consultant for one of the largest engineering firms in the world along with being an associate member of the Institute of Chemical Engineers (IChemE).

The post How Advanced Waterjet Cutting Improves Material Precision in Engineering Manufacturing appeared first on Engineeringness.

BTU, or British Thermal Unit, is a unit of heat measurement used in the US customary system. It quantifies the amount of heat needed to raise the temperature of one pound of water by one degree Fahrenheit. Despite the widespread use of watts in the SI system for power measurement, BTU is still commonly used for heating and cooling systems, especially in air conditioning.

Specifically, BTU per hour (Btu/h) denotes the rate of heat transfer and refers to the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit in one hour as stated above.

How To Convert Tons to BTU?

1 BTU is equivalent to 8.33333 × 10⁻⁵ refrigeration tons. To convert BTUs to tons, simply multiply the number of BTUs by 8.33333 × 10⁻⁵.

What is Ton of Refrigeration?

A ton of refrigeration (symbol: TR or TOR) is a unit of power used to describe heat transfer. One ton of refrigeration is equivalent to the amount of heat required to melt one ton (2000 pounds) of pure ice at 0°C (32°F) over the course of a day. The use of Ice was due to the introduction of a ton of refrigeration being introduced in the late 1800s when large blocks of ice were used to cool houses and business premises. As the ice melted, it absorbed heat from the room, functioning similarly to modern air conditioners. The ice didn’t produce cool air; instead, it removed hot air from the room.

In the USA, the cooling capacity of air conditioning and refrigeration equipment is frequently measured in tons of refrigeration. Manufacturers often provide the capacity in BTU/h as well, particularly for smaller devices.

To convert British Thermal Units (BTU) to tons of refrigeration, you can use a simple conversion formula. One ton of refrigeration is approximately equivalent to 12,000 BTUs per hour. Use our calculator Below to do the conversion.

Convert BTU to Watts

To convert power from watts to British Thermal Units (BTUs) per hour, you can use a straightforward conversion formula. One watt is approximately equal to 3.412142 BTUs per hour.

Formula for Converting Watts to BTUs per Hour

BTU/h = Watts x 3.412142

Conversion Process:

1. Determine the Watts value: Find out the total number of watts that you need to convert.
2. Apply the Conversion Formula:
3. Multiply the number of watts by 3.412142 to find the equivalent in BTUs per hour.

BTU to Tons and Watts Calculator

What Are BTUs in Air Conditioning?

A BTU, or British Thermal Unit, is a unit of measurement used to quantify the amount of heat energy as mentioned earlier. In the context of air conditioning, BTUs measure the cooling capacity of an air conditioning unit. Specifically, one BTU represents the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit.

How BTUs Relate to Air Conditioning

• Cooling Capacity: The BTU rating of an air conditioner indicates its cooling power. The higher the BTU rating, the more cooling capacity the unit has, and the larger the space it can effectively cool.
• Room Size: To select the right air conditioner, it’s important to match the BTU rating to the size of the room. Too few BTUs will result in insufficient cooling, while too many BTUs can lead to high humidity levels and an uncomfortable environment.

Typical BTU Ratings for Air Conditioners

• Small Rooms (100-300 sq ft): 5,000 – 7,000 BTUs
• Medium Rooms (300-500 sq ft): 8,000 – 12,000 BTUs
• Large Rooms (500-1,000 sq ft): 13,000 – 18,000 BTUs
• Extra Large Rooms (>1,000 sq ft): 19,000 – 24,000 BTUs

Importance of Correct BTU Rating

Choosing an air conditioner with the correct BTU rating ensures efficient operation and comfort. An underpowered unit will struggle to cool the space, leading to excessive energy use and wear on the unit. Conversely, an overpowered unit will cycle on and off too frequently, failing to dehumidify the space properly.

Hassan Ahmed

Hassan graduated with a Master’s degree in Chemical Engineering from the University of Chester (UK). He currently works as a design engineering consultant for one of the largest engineering firms in the world along with being an associate member of the Institute of Chemical Engineers (IChemE).

The post BTU vs SI Units: Understanding BTU, Watts and Tons In Refrigeration Using Our Conversion Calculator appeared first on Engineeringness.

Real gases are non-ideal gases that deviate from the assumptions of the ideal gas law, which states that gas molecules do not interact and occupy no volume. In real gases, these assumptions are incorrect due to the finite volume of molecules and their intermolecular forces, especially under certain conditions like high pressure or low temperature.

Assumptions of Ideal Gases

Real gases are non-ideal gases, where two assumptions from the ‘kinetic model’ are not accurate:

1. Gas molecules/atoms occupy space,
2. Gas molecules/atoms interact with each other.

At low pressures and high temperatures, these assumptions hold true, and gases behave ideally. However, at high pressures and low temperatures, the real behaviour of gases change due to molecular volume and intermolecular forces. The ideal gas law (see below) no longer accurately describes the system under these conditions.

Ideal Gas Equation

Equation 1: Ideal gas equation.

Where:

• P – Pressure (Pa),
• V – Volume (m³)
• n – Number of moles (mol),
• R – Ideal gas constant (J/mol·K),
• T – Temperature (K)

Limit  P = 0, is when the assumptions work (Equation 1).

Ideal Gas Law Calculator

Factors Affecting Real Gas Behaviour

To understand the behaviour of real gases, the flowing must be taken into account:

• Compressibility effects
  • Real gases can be compressed more or less than predicted by the ideal gas law.
• Variable specific heat capacity,
  • Real gases do not have a constant specific heat capacity.
• Van der Waals forces,
  • Attractive and repulsive intermolecular forces become significant, especially at high pressures.
• Non-equilibrium thermodynamic effects,
  • Real gases may exhibit non-equilibrium behaviour, especially during rapid processes.
• Issues with molecular dissociation and elementary reactions with variable composition.
  • In some conditions, molecules may dissociate or react, altering their behaviour.

The ideal gas approximation can be used with reasonable accuracy, however at certain conditions such as condensation point of gases, near critical points, at very high pressures, to explain the Joule–Thomson effect (the change in temperature that accompanies expansion of a gas without production of work or transfer of heat) and in other less usual cases, the real gas model would have to be used, with the deviation from ‘ideal’ conditions being described by a term called the compressibility factor, Z.

Compressibility Factor (Z)

The compressibility factor, Z, is the ratio of the measured molar volume of a real gas to the molar volume of an ideal gas at the same temperature and pressure (Equation 2). The compressibility factor is very useful for the modification of ideal gases into real gases, with deviations from ideal becomes more significant the closer the gas is to a phase change, the lower the temperature or larger the pressure.

Therefore, the compressibility factor is:

Equation 2: Compressibility factor equation and the molar volume equations for ideal and real gases.

The Behaviour of The Compressibility Factor (Z)

The compressibility factor generally increases with temperature and pressure, at low pressures Z = 1, which means the gas is ideal. At intermediate pressures Z < 1 and the molecules are free to move to result in attractive forces dominating and a smaller volume. At higher pressures, molecules are colliding more frequently which allows repulsive forces to have a noticeable effect resulting in a higher molar volume making Z > 1. Furthermore, the closer a gas is to its critical point or boiling point, the more Z will deviate from the ideal case (Figure 1).

• At low pressures, Z = 1
• At intermediate pressure, Z < 1
• At higher pressures, Z > 1

Figure 1: Compressibility Factor Graph (Stack Exchange, 2019).

Notice that, although the curves are approaching 1 as P = 0 they do so at different slopes.

Principle Of Corresponding States

The principle of corresponding states states that gases behave similarly at temperatures and pressures normalised relative to their critical temperature (Equation 3) and critical pressure (Equation 4) where gases transition between liquid and gas phases.

Equation 3: Critical temperature equation.

Equation 4: Critical pressure equation.

• T_c – Critical Temperature
• P_c – Critical Pressure
• T_R – Reduced Temperature
• P_R – Reduced Pressure

The Z factor for all gases is approximately the same at the same reduced temperature and pressure. This is called the principle of corresponding and data can be plotted to form a generalised compressibility chart (Figure 2) below.

Figure 2: Generalised diagram of compressibility factor (Pugliesi, 2015).

• At low pressures (Pr << 1), gas behave like an ideal gas regardless of the temperature.
• At high temperature (Tr >> 2), ideal gas behaviour is assumed with god accuracy regardless of the pressure.
• The deviation from the ideal gas condition is greatest around the critical point.

All gases have a critical point, with the temperature, pressure and molar volume at the critical point being the critical constant. Above the critical temperature and pressure, gases behave as both liquid and gas (Figure 3).

Figure 3: Gases and their critical properties (ScienceHQ, 2020).

The Van Der Waals Equation

Two parameters are derived from the molecule’s concepts, repulsion and attraction. First, assume the gas molecules are hard spheres to stress the actual volume available for the molecules (Equation 5):

Equation 5: Transformation of the ideal gas equation with the van der Waals ‘b’ term.

Where:

• a – Corrects for attractive forces between gas molecules
• b – Corrects for the finite volume of gas molecules

The pressure will depend on the frequency and the collision force between gas molecules and the walls of the vessel. As the molar volume decreases, the attractive forces between the molecules increases, thus leading to inverse proportionality (Equation 6):

Equation 6: Equation linking attractive forces and volume/molar volume.

References

Chemguide. (2024). Real gases. Retrieved from https://www.chemguide.co.uk/physical/kt/realgases.html

Pugliesi, D. (2015). File: Compressibility factor generalized diagram.png. Retrieved from Wikimedia Commons: https://commons.wikimedia.org/wiki/File:Compressibility_factor_generalized_diagram.png

ScienceHQ. (2020). Introduction to thermodynamics. Retrieved from ScienceHQ: http://www.sciencehq.com/physics/introduction-to-thermodynamics-2.html

Stack Exchange. (2019). Compressibility Factor Graph. Retrieved from Stack Exchange: https://chemistry.stackexchange.com/questions/107843/compressibility-factor-graph-which-gas-attains-a-deeper-minimum

Wikipedia. (2024). Real gases. Retrieved from https://en.wikipedia.org/wiki/Real_gas

Hassan Ahmed

Hassan graduated with a Master’s degree in Chemical Engineering from the University of Chester (UK). He currently works as a design engineering consultant for one of the largest engineering firms in the world along with being an associate member of the Institute of Chemical Engineers (IChemE).

The post What Is a Real Gas? Differences, Behaviour, and Ideal Gas Law Deviations appeared first on Engineeringness.

Some memory manufacturers have predicted scaling 3D NAND to 1,000 layers within this decade, but the technologies and processes that got us from 2D to 3D, and from 64- to 232-layer 3D NAND are not capable of achieving such unprecedented scale. It will require Lam’s coolest technological breakthrough yet—pushing physics and chemistry to their limits, striving for higher storage capacities and data processing speeds never achieved before in solid-state drives (SSDs).

Building on two decades of leading-edge innovations in dielectric etch technology, Lam Research introduced Lam Cryo™ 3.0 to help overcome the most critical challenges in scaling production of AI-ready 3D NAND.

3D NAND flash involves stacking multiple layers of cells to achieve higher densities for increased data storage capacity and throughput—crucial for AI, Machine Learning and applications that require rapid data retrieval and processing. Creating such architectures involves almost unfathomable complexity for manufacturing at the atomic scale—1,000x smaller than the width of a human hair.

Etching material from the surface of a wafer to achieve desired patterns and memory cell structures is a critical process to enhance 3D NAND device performance, reliability and yield. So, the question of how to achieve higher aspect ratio (HAR) etching—at ever-greater depths and with more precision without compromising quality—has been a hot topic in the semiconductor industry for years.

For Lam, it was about cooling things down. Way down!

Delivering angstrom-level control of lateral and vertical feature profiles, Lam Cryo 3.0 leverages subzero processing temperatures to enable novel chemistries for etching memory channels of up to 10 microns in depth without compromising critical shape dimensions.

When it comes to etching, “memory channel precision” refers to creating vertical pathways in the memory stack that connect the cells, which is vital for scaling 3D NAND devices to higher layer counts. “Logic scaling” requires maintaining top-to-bottom dimensionality of the channels, which is essential for enabling each memory cell to store more bits and increase the performance and capacity of flash memory as it scales to more layers and taller stacks. And beyond this technical complexity for increasing performance and capacity, flash manufacturers must also decrease the operational costs per bit to achieve scale.

Lam’s pioneering efforts in etch and deposition technology over the decades have led to many significant breakthroughs in NAND flash manufacturing using our unique and proprietary technologies, including cryogenic memory channel etch. By lowering wafer temperatures during manufacturing, Lam can leverage novel process chemistries to enable more bits per cell for scaling devices to higher layer counts with deeper etches and greater uniformity than ever before.

Lam Cryo 3.0 represents a significant leap forward in cryogenic etching technology to transform 3D NAND chip manufacturing as it works to meet the demands of the AI era.

Lam played a leading role in the industry’s transition from planar to 3D NAND with its HAR etch solutions that deliver top-to-bottom feature precision. Since 2019, Lam has been the only company with production-proven cryogenic tools for manufacturing advanced NAND devices, boasting a worldwide customer install base of nearly 1,000 chambers used to process over five million wafers.

“Lam Cryo 3.0 cryogenic etch technology is a significant leap beyond conventional techniques,”

says Neil Shah, co-founder and vice president of research at Counterpoint Research.

“It etches memory channels that are more than 50 times deeper than their width with near perfect precision and control, achieving a profile deviation of less than 0.1%. This breakthrough significantly enhances advanced 3D NAND yields and overall performance, enabling chipmakers well in the AI era.”    

Lam’s cryogenic etch technology combines industry-leading high-power confined plasma reactors and pulsed plasma reactor technology with processing temperatures that can reach well below 0^oC. This enables new chemistries for HAR etches essential in scaling 3D NAND layer counts.

With these cryogenic etch innovations, Lam is enabling today’s leading flash memory manufacturers to achieve near-perfect etching profiles for higher throughput, greater efficiencies, and lower environmental impact needed to support next-generation applications. What’s more, manufacturers can scale 3D NAND laterally, vertically, and logically – increasing bit density and capacity from single-level cell (SLC) up to quad-level cell (QLC) for higher storage capacity, performance and energy efficiency.

What’s Cool about Lam Cryo?

With etch rates more than twice as fast as conventional dielectric etching, Lam’s cryogenic etch technologies enable cost-effective bit scaling for faster production and higher yield, with unmatched precision to repeatedly etch memory channels as deep as 10 microns with less than 0.1% deviation* of critical top-to-bottom dimensions. Not only can customers leverage Lam’s cryo-enabled tools while continuing to utilize previously installed etch systems, but the technologies also have the potential to reduce carbon footprints by using novel process gases (and their byproducts) that have a lower overall environmental impact. Furthermore, higher throughput results in lower overall system energy usage with an anticipated 40% reduction in energy consumption per wafer** and a 90% reduction in emissions***.

As we enter the AI age, reaching 1,000-layer 3D NAND represents more than just a technological aspiration; it symbolizes a new paradigm for the semiconductor industry as we work to meet the intensive data processing and storage demands of today and beyond. Lam Research is committed to leading this charge, providing cryogenic solutions and other innovations to help overcome the most critical technological, economic, and manufacturing operational challenges to usher in the AI era.  

Tae Won Kim is CVP of Global Products – Dielectric Etch at Lam Research

Tae Won Kim

Tae Won Kim is CVP of Global Products – Dielectric Etch at Lam Research

The post The Future of Flash Memory is Cooler than you Think appeared first on Engineeringness.

Brazilian Nickel is developing the Piauí Nickel Project in northeastern Brazil with the aim of becoming one of world’s major producers of nickel to supply the growing electric vehicle battery market and provide an alternative to existing global supply chains that are controlled by just a few countries.

The Piauí project has reserves of 104 million tonnes at 0.82% nickel and 0.05% cobalt, with upside potential in adjacent exploration licences. We expect peak production to reach more than 34,000t Nickel and 1050t cobalt and average, over the first 10 years of the operation, 25,000 tonnes per year of contained nickel. Further Brazilian Nickel has received all the necessary installation licenses, meaning it can proceed quickly with construction once financing finalized.

Brazilian Nickel chose to use heap leaching for all the processing at the Piauí project because of its long list of environmental and economic advantages. Heap leaching has the potential to be the lowest capital and operating cost and most environmentally friendly of the processes to recover nickel from laterite ores. It is a low-CO₂ process that uses water efficiently and only produces solid residues, which eliminates the need for an environmentally risky tailings dam. Importantly, it is also a more simple, flexible process and thus is very suitable for remote locations and training of local workforces to operate.

Although heap leaching has not been used for nickel laterite processing on this scale before, it is not an untried or experimental technology. Heap leaching is well established process used for the treatment of copper, gold and uranium. Work first began on nickel laterite heap leaching in the 1990s and the core BRN metallurgical team has been working to commercialise it on a large scale since the early 2000s.

Many aspects of heap leaching technology used for other metals are transferable to nickel laterite processing, though it takes a high degree of expertise. Our metallurgical experts have optimized the process over the years to suit the many deposits studied. The key to heap leaching of nickel laterites is actually iron control and our optimized process does exactly that.

Iron is an impurity in the ore in varying degrees of concentration in different deposits and BRN’s heap leach process minimizes the amount going into solution, basically selectively leaching nickel over the iron. This results in a pregnant leach solution (PLS) with the highest nickel and the lowest iron and acid concentration resulting in a smaller more efficient downstream treatment plant.,.

Since purchasing the Piauí project in 2014 BRN has further demonstrated and improved the process specifically to the conditions at Piauí. The company operated a demonstration plant on the Piauí site with full height heaps in 2016 & 2017, producing nickel and cobalt products that were exported and sold.  In 2021 the demonstration plant was expanded to form the PNP1000, a small-scale operation that ran until the end of 2023, producing nickel and cobalt contained in a Mixed Hydroxide Precipitate (MHP) which was fully qualified by the EV battery cathode value chain.

The ore from the Piauí Nickel Project has excellent metallurgical properties for heap leaching, being high in silica. This results in fast leach kinetics, high nickel and cobalt extractions and, most importantly, low acid consumption. This cements the project as a highly viable, low cost, and low impact method of providing a vital resource for the green economy.

In short, nickel laterite heap leaching is simple and flexible, economically sound and environmentally responsible, and can be applied to the many laterite deposits that currently have no realistic path to production.

Fundamentals of Heap Leaching

In the heap leaching process, very dilute sulfuric acid (similar in strength to some acid‐based household cleaning products) is slowly applied to crushed and agglomerated nickel ore on a lined pad to dissolve the nickel and cobalt contained in the ore. The resulting metal-rich solution is then treated in an ambient temperature and pressure process to firstly remove impurities by precipitation with limestone and then to recover the valuable nickel and cobalt from solution. This is done with a combination of ion exchange circuits and further precipitation to MHP.  

Solutions are continuously recycled, reducing waste and making the process more sustainable.
The final product is an intermediate mixed hydroxide precipitate (MHP) containing ~50% nickel and ~2% cobalt that can then be sold to a large customer base of existing nickel refiners along with the newer EV battery precursor and Cathode Active Material (CAM) producers.

While Brazilian Nickel believes that any nickel laterite is amenable to heap leaching, factors including terrain, weather and distance to ports are crucial in developing a commercially successful project.

Technical Advantages vs. Alternatives Of Heap Leaching

Heap Leaching has much better resource utilization than other processes that treat nickel laterites. Once selected as ore, material is stockpiled and reclaimed to give the right homogeneous mix in the heap. Nickel extraction in the Piauí project is above 80% and downstream losses less than 5% giving a range of global recovery of 76-82%.

Smelting and high-pressure acid leaching (HPAL) typically have recoveries from the target ore zone of 85% to 95%, however these processes have a very specific target ore and therefore total resource recovery is normally in the range of 45% to 60%.

HPAL, currently the hydrometallurgical process of choice for nickel laterites outside of China, uses elevated temperatures (around 255°C) and pressures (around 50 bars) along with sulfuric acid to extract nickel and cobalt from laterite ore. This is much more energy intensive and capital intensive than heap leaching and involves more complex

Most other pyrometallurgical processes, notably ferronickel, nickel pig iron and matte smelting, require a high-energy-intensity smelting process. While HPAL has a lower energy intensity than smelting, estimates suggest that for every tonne of nickel ore processed via HPAL, around 1.5 tonnes of waste is also produced. Typically

Environmental & Sustainability Considerations Of Heap Leaching

Sustainability is a core value at Brazilian Nickel. The Brazilian state is also very focused on environmental issues in mining, and rightly so, given some of the major disasters at mining operations in the past.

In addition to having only dry residues the heap leach process is inherently lower CO₂ than other laterite processes. We also have active research programs to capture and reduce what CO₂ we do emit with the aim of zero carbon production in the future.

The Piauí Nickel full-scale Project will have an on-site acid plant as part of the operation. This means sulphur is transported to the site rather than more dangerous acid shipments. The sulphur burning acid plant cogenerates more than enough electricity to operate the HL operation and usually allows some sale of power back to the country’s grid.

Heap leaching also bypasses the need for fine milling, reducing energy consumption and environmental impact. Furthermore, the process can be applied to low-grade ores that are not economically viable using conventional techniques.

Sustainability is also about what we leave behind. Our objective is to leave behind a positive legacy of stronger, more sustainable communities once mining activities cease. This involves planning and community buy in before, during and after the period of actual mining. I think we’re doing a pretty good job of it, Brazilian Nickel’s Piauí Nickel Metais unit, which operates the Piauí site was awarded the prestigious Nickel Mark award for its unwavering commitment to responsible and sustainable practices across the nickel value chain. While this gives us confidence that we’re on the right track, we are always looking for ways to do more.

Anne Oxley

Anne is the co-founder of Brazilian Nickel a company with sustainability and ethical principles at the forefront of its Agenda. Its flagship Piauí Nickel Project is a nickel heap leach which produced its first intermediate products in 2022. Heap leaching is a low cost and inherently low carbon footprint process and BRN is looking at innovative ways to reduce the project carbon footprint even further with the vision of being carbon negative The Piauí site was awarded the Nickel Mark in May 2024. BRN is a member of the Nickel Institute (the global association of leading primary nickel producers) and in 2025 Anne became Chair of its Board of Directors.

In 2022 Anne was named one of the 25 inaugural ESG champions by the Natural Resources Forum particularly for her work on gender diversity and inclusivity in the mining sector.

Anne is a Chartered Metallurgical Engineer from the Royal School of Mines, Imperial College London. She has over 30 years’ experience in the natural resource sector and has been working in nickel and cobalt since 2003. She is also a scientific associate of the Natural History Museum in London were she continues to contribute to fundamental nickel and cobalt research.

The post Behind Heap Leaching | Mechanics & Technology of Nickel Heap Leaching appeared first on Engineeringness.

The Biot number (Bi) is a dimensionless value in thermodynamics, specifically in heat transfer. The number is named after French physicist Jean-Baptiste Biot. It compares the ease of heat flowing through an object’s surface to how easily it moves within its interior. This is incredibly useful in helping to predict temperature distribution within the body under certain thermal conditions.

• If the Biot number is less than 1, this means heat moves freely inside, so the surface and core temperatures stay nearly the same.
• If the Biot number is less greater than 1, this means the surface heats or cools much faster than the interior, creating a steep temperature gradient.

To learn more about the Biot number and other dimensionless numbers as well as units involved in all thermodynamics studies and beyond, check out the following book:

Biot Number Formula

Where:

• Bi – Biot Number (dimensionless)
• h – Heat Transfer Coefficient at Surface (W/m² K)
• L_c – Characteristic Length of Material (m)
• k – Thermal Conductivity of Material (W/m K)

We can compute the L_c if we have the Volume (m³) and Area (m²) of a surface through which the material is cooled down or heated up.

Biot Number Calculator

When using the calculator below, If the Characteristic Length is known, input the value into the Characteristic Length cell. If this is unknown, make sure the Characteristic Length cell is empty and then input values into both the Volume and Surface Area in order for the calculation to compute the Characteristic Length for you.

Biot Number Uses In Industry

The Biot number plays a role in multiple industrial applications, especially where heat transfer is a critical factor. Below is an overview of some of the key uses of the Biot number in industry. Remember, the Biot number tells you whether an object’s surface heats or cools much faster than its interior. When Bi ≪ 1, the temperature is uniform inside; when Bi ≫ 1, there’s a steep gradient. Here are some key industries the Biot number is used in:

• Food & Beverage
  In pasteurisation and chilling, processors use the Biot number to size tanks and cooling coils so that milk, juice or beer reaches the right temperature evenly; avoiding cold spots that can spoil flavour or safety.
• Metal Casting & Heat Treatment
  Foundries rely on the Biot number to predict how quickly molten metal solidifies. A low Biot number regime means uniform cooling (fewer internal stresses), while a high Biot number indicates the surface freezes first. This means the Biot number can be used to tailor the process to avoid cracks and other defects.
• Pharmaceutical Freeze‐Drying
  In lyophilisation of vaccines and delicate biologics, the Biot number guides how fast heat penetrates the frozen slab. If the Biot number is too high, the surface thaws and dries before the core, risking case-hardening (a shell that traps moisture). A moderate Biot number ensures uniform sublimation and prevents under-dried zones that could compromise potency.
• Electronics Cooling
  From data-centre servers to smartphone chips, designers calculate the Biot number to choose the right thickness for heat sinks or thermal interface materials, ensuring hotspots don’t cook the circuitry before the core can catch up.
• Chemical Reactors & Heat Exchangers
  In petrochemical plants, the Biot number lets designer know the design of jackets and coils that maintain uniform reactor temperatures; maximising yield and preventing runaway reactions at hot or cold zones.

Hassan Ahmed

Hassan graduated with a Master’s degree in Chemical Engineering from the University of Chester (UK). He currently works as a design engineering consultant for one of the largest engineering firms in the world along with being an associate member of the Institute of Chemical Engineers (IChemE).

The post Biot Number Explained | Origins, Significance, Online Calculator & In Depth Guide appeared first on Engineeringness.

What Is Thermal Conductivity?

Thermal Conductivity is defined as how well a material can conduct heat, a characteristic intrinsic to the material itself, unaffected by external factors or the mass of the object. This property is directly related to the amount of heat energy conveyed and the distance over which this heat is transferred, while being inversely related to the difference in temperature throughout the material.

The most common example looked at within educational institutions is a wall with insulation. So consider a wall with insulation. If it only allows a minimal amount of heat to pass through, its thermal conductivity is considered to be low.

We recommend the following book for an introduction into thermodynamics:

Fourier’s Law Definition

Fourier’s Law, states that the rate at which heat is transferred through a material is proportional to the negative gradient of the temperature and the area through which the heat is being transferred. In simpler terms, it means that heat moves from regions of higher temperature to regions of lower temperature, and the amount of heat transferred per unit of time is directly related to how quickly the temperature changes in space (temperature gradient) and the size of the area over which the heat transfer occurs.

Heat Flux Definiton

Heat flux refers to the amount of heat energy that moves through a specific area every second. It is used within Fourier’s Law and is usually combined as seen below.

Heat Flux and Fourier’s Law

According to Fourier’s law, heat flux is defined as:

Where:

• q – Heat Flux, measured in (W/m²)
• Δx – Thickness of the object (or the distance the heat has to travel) in (m)
• ΔT – The temperature difference across the object in (K)
• λ – The Thermal Conductivity of the material (W/mK)

The negative sign expresses the direction of heat transfer. Due to heat always flowing from a warm area to a cold area, the direction of heat transfer is always opposite to the temperature gradient.

​Thermal Conductivity Calculator

Table To Show The Thermal Conductivity Constants of Materials and Substances

Hassan Ahmed

Hassan graduated with a Master’s degree in Chemical Engineering from the University of Chester (UK). He currently works as a design engineering consultant for one of the largest engineering firms in the world along with being an associate member of the Institute of Chemical Engineers (IChemE).

The post The Ultimate Guide to Thermal Conductivity | Calculator, Definitions, and Application appeared first on Engineeringness.

To understand specific heat capacity, its important to understand the basics of thermodynamics. We recommend the following book for an introduction into thermodynamics:

The History of Specific Heat Capacity

Below is a brief timeline we have prepared to allow you to understand the context and history of the idea of specific heat capacity.

We start from the mid-18th century onwards, scientists such as the Scotsman, Joseph Black, first recognised that equal masses of different substances absorb differing amounts of “sensible heat” in his words to change temperature, which was the foundation for what we now call specific heat capacity.

In the 1780s, Lavoisier and Laplace used calorimeters to quantify heat as a fluid (“caloric”) and established the first numerical ratios of heat per degree per mass.

Rumford’s experiments on cannon boring in 1798 challenged the caloric view by demonstrating heat’s mechanical origin, a shift that was compounded by Fourier’s 1822 heat-conduction theory, in which specific heat appears naturally in the equation.

Dulong and Petit’s 1819 law showed that the product of specific heat and atomic weight is nearly constant for solids, aiding atomic-weight determinations, and Regnault’s mid-19th-century precision calorimetry yielded highly accurate tables of specific heats.

With all those developments from some of the best scientists the world has ever seen, we finally reach Joule’s mechanical equivalent. Joule’s use of mechanical equivalent of heat unified heat with energy, giving specific heat its modern definition as the joules required to raise a unit mass by one kelvin.

The Specific Heat Capacity Formula

Where:

• c – Specific Heat Capacity (J/ kgK)
• Q – Energy/ Amount of heat supplied (J)
• m – Mass (kg)
• T – Temperature (°C)

How to Find/ Calculate Specific Heat Capacity?

1. Determine the final and beginning temperature as well as the mass of the bodies you are studying.
2. Subtract the final temperature from the initial temperature to give you the ΔT (°C) for the formula.
3. Multiply the ΔT (°C) with the mass (kg) of the body you are studying.
4. Divide the energy/ heat supplied (J) with the answer to step 3.

Specific Heat Capacity Calculator

This specialised calculator is designed to measure the heat capacity of samples, whether they are being heated or cooled. It quantifies the specific heat, which is the thermal energy required to raise the temperature of a 1 kg sample by 1 K. Continue reading to discover the proper application of the heat capacity formula for accurate outcomes.

Definition of Specific Heat Capacity at Constant Volume

Specific heat capacity refers to the amount of heat or energy needed to raise the temperature of a substance with a fixed volume by 1 degree Celsius per unit mass. The equation for calculating this is given by Cv = Q / (m × ΔT), where Cv represents the specific heat capacity at constant volume.

How Is Specific Heat Capacity Calculated?

The calculation for the specific heat capacity (c) involves the formula c = Q / (m * ΔT), where ‘c’ represents the specific heat capacity of a material with mass ‘m’. In this formula, ‘Q’ stands for the amount of energy introduced or removed, and ‘ΔT’ indicates the temperature variation experienced by the substance. For various processes, such as at constant volume (Cv) or constant pressure (Cp), the relationship between Cv and Cp is determined by the specific heat ratio (ɣ = Cp/Cv) or can be expressed through the gas constant ‘R’, calculated as R = Cp – Cv.

Hassan Ahmed

Hassan graduated with a Master’s degree in Chemical Engineering from the University of Chester (UK). He currently works as a design engineering consultant for one of the largest engineering firms in the world along with being an associate member of the Institute of Chemical Engineers (IChemE).

The post Understanding Specific Heat Capacity | Calculation, Formulas, and Common Values appeared first on Engineeringness.

Zaidi, A., de Leeuwe, C., Chansai, S., Hardacre, C., Garforth, A., Parlett, C., & Spallina, V. (2025). Development of iron-nickel containing perovskites with increased oxygen carrier capacity for chemical looping H2 production. Journal of Environmental Chemical Engineering, 13(1), 115069. https://doi.org/10.1016/j.jece.2024.115069

One of the earliest reference to chemical looping combustion is Lewis and Gilliland, in 1954, publishing ‘Production of Pure CO₂‘ (patent US2665972A), which described a concept like chemical looping combustion, as well the idea of using oxygen carriers to reduce fuels [2]. In the 1980s Richter and Knoche proposed the principle of chemical looping combustion (CLC) to improve fossil fuel power plants [3].

The name CLC was first used by Ishida in the 1980s in a study to reduce exergy losses in natural gas power plants when converting fuel energy into thermal energy [4]. In 1994 Ishida and Jin continued research for the integration of CLC in power plants. They developed a new system for power generation to reduce the exergy destruction caused by combustion and heat exchange and solve the environmental issues associated with CO₂ by recovering and utilising it [5].

In the early 2000s, CLC hadn’t been demonstrated on a large plant scale with only a handful of test cycle runs, with the small number of oxygen carries being investigated [6].

The EU funded CO₂ capture program provided the first notable trial for CLC [7], with the experiment used more than 300 different types of oxygen carriers [8]. Another EU project was the ‘CO₂ Capture and Hydrogen Production from Gaseous Fuels’ (CACHET). This project focused on the different applications for hydrogen production and carbon capture and the integration of chemical lopping in auto-thermal reforming and steam reforming [9].

With the increased funding and attention that chemical looping was receiving, Chalmers university successfully operated a unit for over 1000 hours [10], successfully testing a large CLR unit under conditions like those seen in industry [11]. Feasibility study and simulation was done on a 3 MWe unit [12] and large scale testing demonstrations was done on 455 MWe commercial unit  [13], [14], [15]. 

By 2010 chemical looping processes had achieved more than 3500 hours of continuous operation and a significant number of papers, and patents in the space of 10 years, with testing of 36 different oxygen carrier materials [16].

Chemical Looping In a Packed Bed

A packed bed chemical looping reactor consists of the oxygen carrier particles packed into the reactor with alternating gas feed to the reactor (Figure 1.4). Noorman et al. [17] showed the feasibility of chemical looping using a packed bed reactor, shifting from the fluidised bed and bubbling bed reactors used for chemical looping previously [18]. 

Chemical looping performed in a packed bed reactor conventionally has three stages. The first stage is oxidation in air, producing hot oxygen-depleted air (N₂), which is used for power generation by being fed to a turbine. The next stage is where the oxidised oxygen carrier is reduced using a low-grade fuel, producing CO₂ and H₂O we can be easily separated for CO₂ sequestration. The third stage involves a heat removal stage, but this is dependent on the oxygen carrier being used [19], [20].

The benefit of using a packed bed reactor compared to using a fluidised bed is the difficulty associated with the separation of gases and particles is avoided and full utilisation of oxygen carrier oxidation states [17]. 

The flexibility of the types of chemical looping process in a packed bed reactor has been demonstrated with dry, wet and steam reforming compositions with the process having a dependence on the oxygen carrier used, with high material stability and reactivity being required [20]. 

When operating a PBR for chemical looping, two different velocities must be taken into account; these are the heat front and reaction front (Figure 1.5). The heat front involves the thermal motion of particles, with a velocity slower than the reaction front, with heat transfer occurring when the oxygen carrier is cooled down to the gas inlet temperature. The reaction front is the thin area between separating the hot products from the cool reactants that determines the gas-solid conversion and the heat generated in the bed [19], [21]. 

When significant flow rates go through the reactor, the heat front velocity is greater than the reaction front velocity. The initial solid temperature isn’t affected by the maximum reactor temperature [21].  

Chemical Looping Reforming

Recently, there has been a widening of this focus onto hydrogen production and other chemicals using chemical looping reforming (Figure 1.6) due to its ability of inherent separation producing a pure product coupled with carbon capture [22]. This is the case of syngas for methanol, ammonia and also liquid fuels.

Mattisson et al. [23]  first proposed chemical looping reforming (CLR) in 2001. CLR utilises the same basic principles as CLC, with the difference being the partial oxidation of hydrocarbon fuel to form reformate syngas. H₂O is used to increase the H₂/CO ratio desired for a process like Fischer Tropsch, which requires an H₂/CO ratio of 2 [24]. 

The reformate syngas produced can be put through other processes to produce chemicals such as; H₂, CH₃OH, NH₃, Fischer Tropsch processes. There are variations of CLR depending on the desired; these include steam reforming integrated with chemical looping combustion (SR-CLC), autothermal chemical looping reforming (CLR-A) and chemical looping steam methane reforming (CL-SMR).

Steam reforming integrated with chemical looping combustion

SR-CLC is a syngas generation process that Rydén and Lyngfelt [25] proposed. SR-CLC involves the conversion of steam and hydrocarbons, which is the same as conventional steam reforming. The CLC element is there to provide a source of heat for the endothermic reactions [16].

The reactor configuration used in SR-CLC consists of an air reactor for oxidation of the oxygen carrier and a fuel reactor to reduce the oxygen carrier using a fuel. The reforming stages consist of a series of tubes operated at elevated pressures and packed with the oxygen carrier. The reforming tubs are immersed within the fuel reactor (Figure 1.7), and during the reduction with the hot oxygen carrier, heat is transferred to the tubes for the reforming to occur [26], [27]. 

The position of the reforming tubes is due to the favourable conditions for heat transfer, with the hot particles easily maintaining a good tube wall temperature profile [16], [25]. Furthermore, favourable heat-transfer conditions have improved H₂ selectivity compared to conventional SMR [25].

Producing pure H₂ from SR-CLC requires integrating Water-Gas Shift (WGS) and Pressure Swing Adsorption (PSA), providing 100% carbon capture, which involves separating H₂O from CO_2, which is a simple process compared to the costly and energy-intensive carbon capture used in conventional SMR.  

Issues present with SR-CLC are due to the possible degradation of the reforming tubes due to high temperatures, leading to cracks forming and loss of containment of the oxygen carrier into the air or fuel reactor [27]. Furthermore, the costs increase due to the requirement of WGS and PSA units, H₂ production. Reduction of these costs would be necessary to generate H₂ at a competitive price point. Otherwise, SR-CLC would be a better syngas production process. 

Chemical looping autothermal reforming

H₂ generation using CLR-A requires WGS and PSA units to maximise H₂ from the syngas. CLR-A produces H₂ without an external heat supply, removing the CO₂ emissions caused by external combustion for heat supply [26]. The significant advantage of CLR-A is that the heat needed to convert the hydrocarbon fuel into syngas doesn’t involve costly O₂ production and without any mixing of air with carbon-based fuels [28] (Figure 1.8). 

The heat balance is essential for CLR-A, with the heat generated from the exothermic oxidation of the oxygen carrier using air having to be sufficient enough to satisfy the heat required for the endothermic reduction and reforming stages [26], [28]. 

Other advantages of CLR-A are; less H₂O and oxygen carrier are required per unit fuel feed, no NO_X formation and produces syngas that can be used in methanol production and Fischer Tropsch, that isn’t possible with steam reforming of CH₄ and reduced sulphur poisoning of oxygen carrier [29], [30].

Chemical looping steam methane reforming

CL-SMR is a process that produces pure H₂ and syngas separately. Like other forms of chemical looping, the oxygen carrier is partially reduced by methane in the fuel reactor producing syngas. The next step is the difference with steam being used to oxidise the oxygen carrier to produce pure H₂. An air reactor is sometimes included to recover the oxygen carrier due to steam not fully recovering the lattice oxygen entirely as it is a weak oxidising agent (Figure 1.9) [28]. 

CL-SMR is an attractive option due to the possibilities of producing H₂ and syngas without the need for WGS or PSA units which reduces costs. The oxygen carrier must show high levels of reactivity with both CH₄ and H₂O throughout many cycles and must be resistant to carbon deposition, which can reduce the materials performance and carbon particles reacting the H₂O leading to contamination of the H₂ produced. The current literature is looking at ways to optimise the performance of oxygen carriers (Fe-based, Ni-based, Cu-based etc.) to find a suitable material to be used in CL-SMR [31]. The case (a) is not thermally balanced while case (b) it is because the presence of air is providing heat to the system.

References

• [1] A. Tong, M. V. Kathe, D. Wang, and L.-S. Fan, Handbook of Chemical Looping Technology. 2017. doi: 10.1002/9783527809332.
• [2] K. W. Lewis and E. R. Gilliland, ‘Production of pure carbon dioxide’, 1954
• [3] H. J. Richter and K. F. Knoche, ‘Reversibility of Combustion Processes’, in Efficiency and Costing, 1983. doi: 10.1021/bk-1983-0235.ch003.
• [4] M. Ishida, D. Zheng, and T. Akehata, ‘Evaluation of a chemical-looping-combustion power-generation system by graphic exergy analysis’, Energy, vol. 12, no. 2, 1987, doi: 10.1016/0360-5442(87)90119-8.
• [5] M. Ishida and H. Jin, ‘A new advanced power-generation system using chemical-looping combustion’, Energy, vol. 19, no. 4, 1994, doi: 10.1016/0360-5442(94)90120-1.
• [6] S. Abuelgasim, W. Wang, and A. Abdalazeez, ‘A brief review for chemical looping combustion as a promising CO2 capture technology: Fundamentals and progress’, Science of The Total Environment, vol. 764, Apr. 2021, doi: 10.1016/j.scitotenv.2020.142892.
• [7] A. Lyngfelt, B. Kronberger, J. Adanez, J. X. Morin, and P. Hurst, ‘The grace project: Development of oxygen carrier particles for chemical-looping combustion. Design and operation of a 10 kW chemical-looping combustor’, in Greenhouse Gas Control Technologies, 2005. doi: 10.1016/B978-008044704-9/50013-6.
• [8] J. X. Morin and C. Béal, ‘Chemical Looping Combustion of Refinery Fuel Gas with CO2 Capture’, in Carbon Dioxide Capture for Storage in Deep Geologic Formations, 2005. doi: 10.1016/B978-008044570-0/50123-9.
• [9] M. Rydén et al., ‘Developing chemical-looping steam reforming and chemical-looping autothermal reforming’, in Carbon Dioxide Capture for Storage in Deep Geologic Formations – Results from the CO2 Capture Project, First Edit., vol. 3, Cplpress, 2009, ch. 14, pp. 181–200.
• [10] C. Linderholm et al., Chemical looping combustion with natural gas using spray-dried NiO-based oxygen carriers, vol. 3. 2009.
• [11] M. Rydén et al., ‘Developing chemical-looping steam reforming and chemical-looping autothermal reforming’, in Carbon Dioxide Capture for Storage in Deep Geologic Formations – Results from the CO2 Capture Project, First Edit., vol. 3, Cplpress, 2009, ch. 14, pp. 181–200.
• [12] N. Berguerand and A. Lyngfelt, ‘The use of petroleum coke as fuel in a 10 kWth chemical-looping combustor’, International Journal of Greenhouse Gas Control, vol. 2, no. 2, 2008, doi: 10.1016/j.ijggc.2007.12.004.
• [13] C. Béal et al., ‘Development of Metal Oxides Chemical Looping Process for Coal-Fired Power Plants’, Darmstadt: 2nd International Conference on Chemical Looping, Sep. 2012.
• [14] L. Zeng et al., ‘Coal Direct Chemical Looping Retrofit to Pulverized Coal Power Plants for In-Situ CO2 Capture’, Columbus, 2013.
• [15] H. E. Andrus, Jr., J. H. Chiu, C. D. Edberg, P. R. Thibeault, and D. G. Turek, ‘Alstom’s Chemical Looping Combustion Prototype for CO2 Capture from Existing Pulverized Coal-Fired Power Plants’, Pittsburgh, PA, and Morgantown, WV (United States), Sep. 2012. doi: 10.2172/1113766.
• [16] J. Adanez, A. Abad, F. Garcia-Labiano, P. Gayan, and L. F. De Diego, ‘Progress in chemical-looping combustion and reforming technologies’, 2012. doi: 10.1016/j.pecs.2011.09.001.
• [17] S. Noorman, M. van Sint Annaland, and Kuipers, ‘Packed Bed Reactor Technology for Chemical-Looping Combustion’, Industrial & Engineering Chemistry Research, vol. 46, no. 12, Jun. 2007, doi: 10.1021/ie061178i.
• [18] R. Ocone, ‘Transport phenomena in packed bed reactor technology for chemical looping combustion’, Chemical Engineering Research and Design, vol. 90, no. 10, Oct. 2012, doi: 10.1016/j.cherd.2012.02.012.
• [19] V. Spallina, F. Gallucci, and M. van Sint Annaland, ‘Chemical Looping Processes Using Packed Bed Reactors’, in Handbook of Chemical Looping Technology, 2018. doi: 10.1002/9783527809332.ch3.
• [20] V. Spallina, B. Marinello, F. Gallucci, M. C. Romano, and M. Van Sint Annaland, ‘Chemical looping reforming in packed-bed reactors: Modelling, experimental validation and large-scale reactor design’, Fuel Processing Technology, vol. 156, 2017, doi: 10.1016/j.fuproc.2016.10.014.
• [21] R. Gort and J. J. H. Brouwers, ‘Theoretical analysis of the propagation of a reaction front in a packed bed’, Combustion and Flame, vol. 124, no. 1–2, 2001, doi: 10.1016/S0010-2180(00)00149-8.
• [22] X. Zhu, Q. Imtiaz, F. Donat, C. R. Müller, and F. Li, ‘Chemical looping beyond combustion-a perspective’, 2020. doi: 10.1039/c9ee03793d.
• [23] T. Mattisson and A. Lyngfelt, ‘Applications of chemical-looping combustion with capture of CO2’, in Second nordic minisymposium on carbon dioxide capture and storage, 2001.
• [24] C. Allevi and G. Collodi, ‘Hydrogen production in IGCC systems’, in Integrated Gasification Combined Cycle (IGCC) Technologies, Elsevier, 2017. doi: 10.1016/B978-0-08-100167-7.00012-3.
• [25] M. Rydén and Lyngfelt. A, ‘Using steam reforming to produce hydrogen with carbon dioxide capture by chemical-looping combustion’, Int J Hydrogen Energy, vol. 31, no. 10, Aug. 2006, doi: 10.1016/j.ijhydene.2005.12.003.
• [26] M. Luo et al., ‘Review of hydrogen production using chemical-looping technology’, 2018. doi: 10.1016/j.rser.2017.07.007.
• [27] M. R. Rahimpour, M. Hesami, M. Saidi, A. Jahanmiri, M. Farniaei, and M. Abbasi, ‘Methane Steam Reforming Thermally Coupled with Fuel Combustion: Application of Chemical Looping Concept as a Novel Technology’, Energy & Fuels, vol. 27, no. 4, Apr. 2013, doi: 10.1021/ef400026k.
• [28] M. Ortiz, A. Abad, L. F. de Diego, P. Gayán, F. García-Labiano, and J. Adánez, ‘Optimization of a chemical-looping auto-thermal reforming system working with a Ni-based oxygen-carrier’, Energy Procedia, vol. 4, 2011, doi: 10.1016/j.egypro.2011.01.071.
• [29] H. RYU, G. JIN, and C. YI, ‘Demonstration of inherent CO2 separation and no NOx emission in a 50kW chemical-looping combustorContinuous reduction and oxidation experiment’, in Greenhouse Gas Control Technologies 7, Elsevier, 2005. doi: 10.1016/B978-008044704-9/50238-X.
• [30] F. García-Labiano, L. F. de Diego, P. Gayán, J. Adánez, A. Abad, and C. Dueso, ‘Effect of Fuel Gas Composition in Chemical-Looping Combustion with Ni-Based Oxygen Carriers. 1. Fate of Sulfur’, Ind Eng Chem Res, vol. 48, no. 5, Mar. 2009, doi: 10.1021/ie801332z.
• [31] M. H. S. Garai, M. R. Khosravi-Nikou, and A. Shariati, ‘Chemical Looping Steam Methane Reforming via Ni‐ferrite Supported on Cerium and Zirconium Oxides’, Chem Eng Technol, vol. 43, no. 9, Sep. 2020, doi: 10.1002/ceat.202000054.

Dr. Adam Zaidi

Dr. Adam Zaidi, PhD, is a researcher at The University of Manchester (UK). His doctoral research focuses on reducing carbon dioxide emissions in hydrogen production processes. Adam’s expertise includes process scale-up and material development.’

The post Fe-Based Chemical Looping | Upgrading Steam-Iron for Efficient Ammonia & Hydrogen Production with CO₂ Capture appeared first on Engineeringness.

To learn more about Nuclear Reactors or just to get a good headstart on your education or to bolster your professional career, check out the following book which has been recommended by numerous industry professional and professors alike:

Different Types of Advanced Nuclear Reactors:

• Advanced Gas-cooled Reactors (AGRs),
• Pressurized Water Reactors (PWRs),
• Boiling Water Reactors (BWRs),
• Pressurised Heavy Water Reactors (PHWRs).

What Are Advanced Gas-cooled Reactors (AGRs) and How Do They Work? 

AGRs make use of carbon dioxide as a coolant and graphite as a moderator, thereby allowing them to operate at high temperatures, hence greater thermal efficiency, usually around 40%. This is because, unlike water, carbon dioxide is stable at high temperatures without causing phase change (e.g., boiling) under the conditions designed in AGRs. High operating temperatures allow a higher percentage of the heat generated by fission to be converted into mechanical and thus electrical energy therefore, higher thermal efficiency.

Graphite is an effective neutron moderator even at high temperature. Its characteristic moderation of the fast neutrons without a significant loss of moderating efficiency at high temperature makes it a highly suitable material for a reactor core where high-temperature operation is required such as AGRs.

This choice of coolant and moderator also allows a wider range of uranium fuels to be used. However the construction and maintenance of the said reactors is far more expensive compared to their counterparts due to the materials required for high-temperature operations. 

What Are Pressurized Water Reactors (PWRs) And How Do They Work?

Pressurized Water Reactors (PWRs) are one of the most widespread and most used types of nuclear reactors. They utilise water for two primary purposes: cooling the core of the reactor and moderating (slowing down) neutrons emitted during fission.

Within the reactor core, the uranium fuel undergoes nuclear fission, where the uranium atoms disintegrate and release heat. Heat is generated as fast neutrons are slowed down through collision in the water, which acts as a moderator. The moderated neutrons are more probable to trigger subsequent fission reactions, sustaining the chain reaction in a controlled manner.

The water circulated through the core serves a dual purpose. It removes the heat produced by fission, acting as a coolant, and slows down neutrons acting as a moderator. The pressuriser maintains pressure on the water. The high pressure, increases the boiling point of water, thus, preventing the water from boiling even at such temperatures as it reaches, allowing it to efficiently carry heat away from the reactor core.

After absorbing heat in the reactor core, the pressurised heated water travels through a heat exchanger known as the steam generator. In the steam generator, the heat from the primary water circuit is transferred to a separate water system. This secondary water is not under high pressure and is allowed to boil, creating steam.

The steam produced in the secondary loop is directed to turbines. As the steam expands and cools, it drives the turbine blades, which in turn rotates a generator. This mechanical energy conversion produces electricity. After passing through the turbine, the steam is usually condensed back into water and recirculated to be heated again, completing the cycle.

Overall, the design of a PWR; with its high-pressure primary water loop and a separate secondary steam cycle, provides a reliable and efficient means of harnessing nuclear energy while ensuring safety and operational stability.

What Is A Boiling Water Reactor (BWR) and How Does It Work?

A Boiling Water Reactor (BWR) works by placing uranium fuel assemblies within the reactor core, where nuclear fission generates both heat and fast neutrons. When these neutrons strike water molecules that are being circulated through the core, the water heats up and, at the same time, serves as a moderator, cooling the neutrons down enough to allow for a controlled chain reaction. Because the coolant water is allowed to boil when it comes into contact with the fuel, steam is produced directly in the reactor vessel; eliminating the need for a separate steam generator loop like in the PWRs.

Once produced, the steam flows directly from the reactor core to the turbine, causing its blades to spin and driving an electric generator. Upon exiting the turbine, the steam is channeled into a condenser, where it is cooled, condensed back to liquid, and pumped back into the reactor vessel to loop again. Internal recirculation variable speed motor pumps inside the reactor use the water flow rate through the core so that the boiling rate and hence the reactor’s power level can be adjusted by the operators without needing to shift control rods.

Control rods, made out of neutron-absorbing elements. Common types of material used to make the control rods are: Boron Carbide (B₄C) and Hafnium. The control rods are added from above to regulate the fission rate and provide for safe levels of reactivity. On a sudden decrease in pressure or water levels, a number of emergency core cooling systems can flood additional coolant into the system in order to prevent overheating. All this within a sturdy containment building designed to protect against the release of any radioactive material upon an accident occurring.

BWRs are relatively compact, since fewer mechanical and heat‑exchange loop elements are required. However, because the steam employed to drive the turbine is radioactive, rigorous water chemistry controls must be implemented to minimise corrosion and limit the formation of radioactive deposits. BWRs typically have thermal efficiencies of around 32–34%, with operating pressures of around 7 MPa and temperatures of around 285 °C. This combination of simple steam production and minimised circuitry makes BWRs cost-effective to build and simple to operate but still demanding fine control of materials and safety protocols.

How Is a BWR Different From a PWR Reactor?

Compared to the secondary loop PWRs, the steam that is generated in the BWR core is utilised to directly drive a turbine that is connected with a generator to produce electricity. The steam is thereafter condensed into water in a condenser and recycled back to the reactor core for reheating. Control rods, made of neutron-absorbing materials, are inserted into or withdrawn from the reactor core to control the rate of fission and, consequently, the quantity of steam produced. This direct cycle of heating water to produce steam in the reactor simplifies the design and operation of BWRs, without a separate steam generator and with a less cumbersome system.

Safety systems are in place to cool the reactor and contain radioactive materials in the event of an emergency, ensuring the safe operation of the reactor.

What Are PHWRs And How Do They Work ?

Pressurised Heavy Water Reactors (PHWRs) are characterised by their use of heavy water (D2O) for both cooling and moderating neutrons, enabling the efficient use of natural uranium as fuel. Heavy water has a much lower neutron‑absorption cross‑section. This means that when fast neutrons from fission collide with D₂O molecules, they are slowed (moderated) into the thermal energy range without being captured as readily as they would be in H₂O. Although heavy water behaves chemically like ordinary water, each molecule contains deuterium atoms (hydrogen isotopes with an extra neutron), making it about 11% denser.

This design allows for significant moderation of neutrons, increasing the probability of nuclear fission reactions without necessitating the enrichment of uranium. The heavy water circulates around the reactor core, collecting the heat caused by fission, and transfers it to a secondary water circuit via a heat exchanger, creating steam without direct contact between both circuits. The steam powers turbines that produce electricity, and the steam is afterwards condensed and recycled.

PHWRs are fueled with natural uranium dioxide pellets, which are contained in rods that are clustered together, and utilise control rods to regulate the fission rate and power. One of the distinctive advantages of PHWRs, particularly of the CANDU design, is that they have the capability for online refueling, i.e., they can be operated continuously without being shut down to replace the fuel. This operational flexibility, together with the possibility of using unenriched uranium, is what PHWRs provide economically despite the added cost and complexity of heavy water use.

Advantages and Disadvantages of Different Types of Nuclear Reactors

Hassan Ahmed

Hassan graduated with a Master’s degree in Chemical Engineering from the University of Chester (UK). He currently works as a design engineering consultant for one of the largest engineering firms in the world along with being an associate member of the Institute of Chemical Engineers (IChemE).

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