|Title||Lang Process Carbon Capture Technology|
|Spatial Coverage||Kauai, Hawaii|
|Subject||AFRC 2013 Industrial Combustion Symposium|
|Description||Paper from the AFRC 2013 conference titled Lang Process Carbon Capture Technology by Jerry Lang|
|Abstract||With the current shift in government regulatory compliance mandating lowered carbon footprint, the energy industry stands to face stiff economic penalties unless a practical and non-energy-intensive process is utilized to reduce emissions. The primary difficulty in removing carbon dioxide and particulate matter from fired-duty combustion gases is the separation step. In many cases the energy required for the separation of the undesirable matter represents a financial investment that is higher than paying penalties. Stiffer penalties centered on emissions reduction and control will continue to drive technology toward practical solutions to the carbon dioxide issue. The Lang Process Unit employs a patented separation process that separates and sequesters the carbon dioxide and other particulate matter. This separation process is accomplished by simple centrifugal mechanics and is low-energy-intensity. Once the carbon dioxide and particulate matter have been separated from the remaining benign gases, there are a number of treatment options that reduce the carbon dioxide into a benign state as well. As this technology is developed and improved, the future of the energy industry is brighter with a practical solution to the carbon dioxide problem.|
|Rights||No copyright issues|
© JLCC, Inc. | Lang Process Carbon Capture Technology | Confidential & Proprietary The Lang Process Sequestration of Heavy Molecular Weight Combustion Products from Lower Molecular Weight Species in Fired-Duty Combustion Sources via Vortex Separation By: David Taylor, P.E. For: Jerry Lang Presented By: David Taylor © JLCC, Inc. | Lang Process Carbon Capture Technology | Confidential & Proprietary Abstract With the current shift in government regulatory compliance mandating lowered carbon footprint, the energy industry stands to face stiff economic penalties unless a practical and non-energy-intensive process is utilized to reduce emissions. The primary difficulty in removing carbon dioxide and particulate matter from fired-duty combustion gases is the separation step. In many cases the energy required for the separation of the undesirable matter represents a financial investment that is higher than paying penalties. Stiffer penalties centered on emissions reduction and control will continue to drive technology toward practical solutions to the carbon dioxide issue. The Lang Process Unit employs a patented separation process that separates and sequesters the carbon dioxide and other particulate matter. This separation process is accomplished by simple centrifugal mechanics and is low-energy-intensity. Once the carbon dioxide and particulate matter have been separated from the remaining benign gases, there are a number of treatment options that reduce the carbon dioxide into a benign state as well. As this technology is developed and improved, the future of the energy industry is brighter with a practical solution to the carbon dioxide problem. © JLCC, Inc. | Lang Process Carbon Capture Technology | Confidential & Proprietary Introduction The race to find an economical solution to the carbon dioxide quandary is on, and the energy industry has high stakes in the game. With the current political climate building the inertia behind huge investments in green technology, it' is open season for an innovative and practical solution to the requisite carbon footprint that remains after every British Thermal Unit is burned to drive growing and recovering economies. There is no doubt that expensive energy is a serious impediment to the progress of emerging from the trenches of economic contractions. Current and future legislation surrounding carbon-based emissions stands to continue penalizing the energy industry for decades to come, with the severity ever-increasing, and constraints becoming tighter every year. It is clear that Bi-Partisan Congress will continue to move forward with new policies that become increasingly more difficult to meet, often to a point where current technology is incapable of achieving. The emergence of industry emissions-based derivatives and the ‘Cap and Trade' system will provide a financial instrument for exchanging the ‘currency' of green technology: carbon credits. Carbon credits, available to companies on a financial exchange platform, will be required in order to generate carbon dioxide that is released into the atmosphere. Companies that are able to reduce their emissions rates to an extent, will be awarded carbon credits as an incentive to continue to operate with a smaller carbon footprint. Although this system appears to be nothing more than a ‘carbon tax', if properly managed it can offer significant strength to energy companies that invest in technology that actually generates a net positive flow of carbon credits, rather than operate by purchasing carbon credits on the open market. The ability for energy companies to forecast with less uncertainty and speculation provides a safer and more economically-friendly environment for potential growth and additional job creation. Major energy industries in the U.S. such as motor fuels and coal are facing severe penalties in the near future unless a mitigation effort is in place to counter the ever-increasing depletion of resources just to keep the doors open. If a practical solution can be found, the U.S. stands to move closer to complete energy-independency, rather than the other direction as it has been in the last several years. JLCC and the Lang Process Unit's patented carbon capture technology will launch the next generation of practical green technology, and begin the great campaign to bringing environmentally friendly profits back to the energy industry in the U.S. © JLCC, Inc. | Lang Process Carbon Capture Technology | Confidential & Proprietary Technical Basis Example Fired Duty and Basic Combustion Equation The technical basis for this report will present a fired duty combustion process that utilizes natural gas. A standard example duty, or firing rate, will be used for simplicity. An air rate for the combustion calculations will be used that generates an average of 3% excess oxygen. In order to drive industrial processes and provide economy-driven resources such as transportation and electricity, stored energy fossil fuels in the form of hydrocarbons can be burned to release that stored energy. The drawback to this process, and the driver behind the Lang Process Unit, is the release of undesirable combustion products such as carbon dioxide. The most basic hydrocarbon, methane, is a single carbon atom bonded with four hydrogen atoms and is the primary component of natural gas. The properties of methane and basic combustion equation are shown below. Basic units of measurement in this equation are moles; you can see a 1:1 ratio of moles methane to moles carbon dioxide in the combustion process. The spherical atoms make up the molecules. The color scheme shown here will be used throughout the report. When methane is burned in fired-duty equipment or combustion engines, the heat is released to produce the work driving the engine or process. The gross energy potential for release, or high heating value, for methane is exploited through the combustion reaction. The table below includes the molecular weight, volumetric and molar high heating values, and the molar rate of methane required to produce a million btu per hour duty. Molecular weight, or molar density, is simply the specific weight of the molecules per unit volume and is analogous to more familiar examples, such as the density of water or air. Duty is © JLCC, Inc. | Lang Process Carbon Capture Technology | Confidential & Proprietary the total gross energy release from combustion reactions. High heating values are in essence the gross energy contained in a non-combusted unit of volume or moles. Molecular Weight and Specific Gravity of Gases The concept of a mole and molecular weight is explained in this way: a mole is a value that represents a huge number of anything, such as the number of molecules in a weighted sample of gas. It is not in reference to the burrowing animal, but for mathematical purposes: it can be used in the same way as a volumetric reference. For example, a mole of an ideal gas at standard temperature of 60 F and 14.7 psia takes up approximately 379 cubic feet of space. The molecular weight comes into play when referencing molar volumes. A mole of methane, for instance, weighs 16 pounds. The several participants in our combustion reaction all possess varying molecular weights, as seen below. Note that air is composed of 79% nitrogen and 21% oxygen. In engineering calculations, a common material is often used as a reference tool to compare relative intrinsic properties, such as density. When calculating relative densities the comparative reference used is the specific gravity. This is simply the ratio of a molecule's own © JLCC, Inc. | Lang Process Carbon Capture Technology | Confidential & Proprietary density to that of air. You are left with a dimensionless constant that can be used to calculate densities from the molecular weight of gases. See the equation below: For example, methane with its mole weight of 16 lb / mole has a specific gravity of 16 / 28.8 = 0.55. Conversely, to determine the mole weight of carbon dioxide which has a gravity of 1.53, you would find it by 1.53 * 28.8 = 44 lb / mole. A table that reviews all mentioned components lists relative weights to air, or gas specific gravity is shown below. Note for example, that air is nearly twice as dense as methane. Also, carbon dioxide is approximately 150% the density of air. Sulfur dioxide and nitrogen dioxide, both undesirable products, represent concentrations in the total small enough to be measured in parts per million; however, it is important to note that they are denser than carbon dioxide. Looking again at the relative gravities of the combustion products you can see that the undesirable CO2 is at the least 1.53/1.11 ~ 38% more mass per volume than oxygen and at the most 1.53/0.62 ~ 247% more mass per volume than water vapor. Given the previous example of how a mixture of two different densities separates via vortex forces, you can deduce that under similar conditions the four species below would separate into distinct layers, based on their gravities. © JLCC, Inc. | Lang Process Carbon Capture Technology | Confidential & Proprietary Combustion Basics and Excess Air The combustion process requires proper mixture of fuel, heat and air. The air provides the necessary oxygen for the combustion reaction. A flame will continue to burn with an adequate source of air and fuel. A flame will extinguish if either runs out. It is important to operate a furnace with a small amount of excess air for safety considerations. As with most industries that utilize fired-heater sources for driving the processes used to generate products, the levels of each component in the combustion triangle are carefully controlled. A typical level of excess air, or an amount above what is required for full combustion, is around 3% excess. This is the value that will be considered for the technical basis of this paper. An expanded and balanced combustion equation for methane is shown below that represents a million btu per hour duty, with 3% excess oxygen. The ‘extra' oxygen does not react again with any of the fuel in complete combustion, as all the fuel has been turned into reaction products and it simply floats away with the other species. © JLCC, Inc. | Lang Process Carbon Capture Technology | Confidential & Proprietary Relative Volume Percentages of Combustion Components With the stoichiometric coefficients maintained for balance, it can be observed that for every mole of methane combusted, a mole of carbon dioxide is produced. Once the molar balance is complete, it can also represent a relative volume balance. As shown in the balanced combustion equation above, each representative component term is beneath its individual volume percent of the total. Carbon dioxide makes up approximately 9% of the total volume for a 3% excess oxygen combustion reaction. In the table below, the reactants, or fuel and air in the combustion reaction, are listed with their molecular weights, and with their total contribution to the volume of gas entering the reaction. It is apparent that the bulk of the volume is made up of air. Methane, the fuel, is the lightest species and is the only gas with accessible heating value from combustion. The products are listed in a similar fashion below. Note that the methane undergoes molecular change and becomes two new species: carbon dioxide and water. It is this arrangement into combustion products that releases the energy from the severing and reformation of chemical bonds. From an environmentally conscious point of view, the only component in the combustion products that represents an area of concern is the carbon dioxide. Two dioxides, nitrogen dioxide and sulfur dioxide are also of concern but represent only a tiny fraction of the total. With the relative volume percentages in table form, it is easy to deduce that if you could truncate a segregated stream of each combustion product, the carbon dioxide portion © JLCC, Inc. | Lang Process Carbon Capture Technology | Confidential & Proprietary represents approximately 10% of the total, or one tenth. With gases, this separation will not naturally occur without either the ability to settle in essentially within zero-velocity surroundings, or via mechanical separation, to be examined later in the report. In typical conditions such as a combustion stack or exhaust pipe, the combustion products are in constant motion, with high rates of molecular motion, and are equally mixed throughout the entire volume. Natural Settling and Centrifugal Separation Natural gravity settling occurs when fluids of different density, or specific gravity, are allowed time to separate into layers of ascending density, as seen in the example of a static gradient below. The driving force for separation is the gravitational constant that all mass is held to. Over time, gravity and natural stagnant settling would create segregated layers, or stratification, of the components. The borders would be interfaces between changing molecular weight, or density. Given the lack of any outside work or energy input, this stratification could only occur in a heterogeneous mixture of fluids, left in a zero-velocity, disturbance-free environment with nearly zero heat transfer to create a temperature gradient, which would lead to continuous mixing of the variety of fluid densities, and the dissolution of the static gradient. In many industrial cases where solid particulates must be removed from a gas stream, the separation step is accomplished by employing centrifugal, or vortex separation. This process exploits the large difference in the density of the contaminant particulates, and involves increasing the stream's speed through rotating equipment or via pressure drop through orifices or nozzles, then directing the stream tangentially into centrifugal separation mechanisms such as cyclones. Note the figure below describing a typical cyclone separator to removed particulates from clean air. The dirty air enters the cyclone at high velocity and tangentially into the curve of the cyclone. As the solid/gas mixture begins spinning in a helical pattern, vortex separation occurs, © JLCC, Inc. | Lang Process Carbon Capture Technology | Confidential & Proprietary as the solid particles cannot maintain the tight spiral that the less dense air molecules follow. Due to the density difference between the solids and the air, which can be as much as 1.5 - 3 times, physics takes over and the separation can occur. The denser particles hit the edges of the cyclone due to higher inertial forces and drop down into the collection area, removed from the air stream. The clean, particle free air turns upward and follows a straight line through the center of the vortex and leaves the upper exit of the cyclone. Using a similar process, the Lang Process Unit concentrates the carbon dioxide into an outer ring within a combustion stack prior to removal. An internal structure that imparts additional spin similar to rifling within a firearm barrel, directs the spin upward toward the stack exit, and the truncation mechanism. After examination of this common industrial separation, consider an alternate method to create the layers of segregation artificially by imparting a similar centrifugal force to the mixture, and harnessing the differences in mass and momentum of each component. © JLCC, Inc. | Lang Process Carbon Capture Technology | Confidential & Proprietary Examining the layers from an upper or lower perspective, and visualizing the container in a way that the molecules are spinning tangentially to the inside of a pipe (such as a combustion stack) with congruent stratifications imparted by centripetal force, a cross-sectional slice of the pipe would yield the following: Note that the lighter molecular weight components have migrated inward, with their flow path predicated on their lower density and molecular weight, and therefore placing them at the innermost region of the pipe diameter, as defined as the lowest-intensity region of the momentum gradient. The outermost region of course, represents the highest molecular weight layer, and the highest-intensity region of the momentum gradient. Ignoring negligible compression of any one layer due to radial forces, each layer would represent a fraction of the total cross-sectional area of the pipe, based on the total volume of each component from the original, balanced combustion equation. © JLCC, Inc. | Lang Process Carbon Capture Technology | Confidential & Proprietary Visualizing again, a column of segregated gases spinning upward toward a combustion stack exit, it might appear something like the figure above, with false-color coordination to show the different layers. Again, reviewing table X above, the carbon dioxide represents approximately 10% of the total by volume, and in the column, approximately the same amount of cross-sectional area of the total. How then, are the gradients formed? Uniform Circular Motion and Radial Acceleration Creates the Gradients When considering this separation at a molecular level, we can take a look at individual carbon dioxide molecules which are in fully developed, and constant angular motion. As the molecule rotates about the axis of spin, its constant velocity is tangential to a point on the arc of a circle. The velocity, a vector quantity, imparts magnitude and direction. The intended path of the molecule would fly off of the arc, if it were not for the centripetal (center-seeking) acceleration inward. In order to maintain the angular velocity, the centripetal acceleration towards the center or axis of spin must occur for every molecule. According to physics, this acceleration must come from a force, and is derived from the following equation: © JLCC, Inc. | Lang Process Carbon Capture Technology | Confidential & Proprietary In the equation above, "F" and "a" represent vector quantities toward the center of the rotation, or axis. The mass of the particle, or molecule in this instance, is "m". The acceleration vector is responsible for changing the direction of the velocity without changing its speed. The acceleration is derived from: The velocity, or "v" component represents the angular speed about the axis, and the radius "r" is the distance from the axis. Substituting, the relative average force is equal to: In a grossly exaggerated frame of reference, the figure below represents the relative directions of the velocity and forces involved. Consider the following equation for momentum, or by definition a vector quantity that also represents resistance to acceleration, of which is the product of a particle's mass and velocity: If the mixture were placed inside a container, and subjected to sufficient spin, identical layers would form due to the radial forces and the differences in specific molecular mass of the components. Instead of a static gradient imparted by gravity and settling alone, a momentum gradient created by the axial forces would be the basis for the segregation, with each gradient interface and layer proportional to each species' molecular weight. © JLCC, Inc. | Lang Process Carbon Capture Technology | Confidential & Proprietary The Separation Step Reviewing the information to this point one can visualize that the annulus created by the carbon dioxide's segregation into its own distinct layer of the momentum balance as shown above. With nothing utilized to cut, or truncate the undesirable layer, the entire gas stream would rise and enter the atmosphere as seen in the figure below: Now consider the following figure that represents the Lang Process Unit's separation step, with an internal annulus partition which truncates and re-directs the CO2-rich stream away from the stack for storage and/or treatment: Finally, consider the following figure, which illustrates the source of the work required to impart sufficient spin to create the stratification of the molecules. A stream from the main combustion gas route is taken off and directed into the suction of a blower. The blower imparts sufficient driving force through the pressure drop between the discharge and the entry into the © JLCC, Inc. | Lang Process Carbon Capture Technology | Confidential & Proprietary stack. The gas increases in velocity, and re-enters the stack tangentially. In addition to this tangential direction, the Lang Process Unit employs spin veins, or rifling, which aid in creating the upward spin. Velocity can be adjusted by utilizing dampers in the suction and discharge lines of the blower. Blower The stream located in the upper right corner of the figure above represents the separated CO2 rich stream ready for any of the established sequestration or treatment schemes available. The Lang Process has successfully separated carbon dioxide from a combustion source.