This document discusses improving the control of lime mud kilns by replacing the traditional cold end temperature control loop with a delta temperature control loop. The cold end temperature loop controls moisture similarly to how exhaust temperature controls moisture in rotary dryers, which has proven ineffective. A delta temperature loop that subtracts the cold end temperature from the hot end temperature provides better moisture control by accounting for changes in evaporative load. Implementing a delta temperature loop is expected to reduce moisture and length variations in the drying and calcining zones by at least 30%, improving the quality and efficiency of lime production.
This document provides formulas and examples for sizing vacuum receivers and pumps for vacuum thermoforming applications. It includes:
1) An equation for determining the size of a vacuum receiver based on mold volume, initial pressure, vacuum system pressure, and combined pressure.
2) An example calculation using the equation to determine a 54 gallon receiver is needed.
3) Equations for calculating the combined system pressure given an existing receiver size or determining the flow rate needed to achieve a given pump down time.
This document describes the development and validation of a mathematical model for a radial flow ammonia converter. The model equations account for material and energy balances across the three catalyst beds. Comparison to plant data from Abu Qir Fertilizers Company showed good agreement between the model and actual performance. The model is useful for optimizing operating conditions, evaluating catalyst performance over time, and determining the effects of adding a fourth catalytic bed.
Capacity Enhancement of Ammonia Production By The Revamping of Ammonia.
In this project, we find conversion and temperature profile of a two catalyst bed with one interbed heat exchanger ammonia converter and a three catalyst bed with two interbed heat exchanger ammonia converter both have radial flow by using a pseudo homogeneous two dimensional mathematical model on the basis of principle of conservation of mass and energy balance with the help of MATLAB pde solver.We conclude that a three catalyst bed ammonia converter give a higher conversion and lower pressure drop compare to the two catalyst bed ammonia converter for the same volume of catalyst bed and same amount of feed stock.
A QUICK ESTIMATION METHOD TO DETERMINE HOT RECYCLE REQUIREMENTS FOR CENTRIFUG...Vijay Sarathy
Turbomachinery Engineers often conduct studies to determine if a hot gas bypass is required for a given centrifugal compressor system. This would mean building a process model and simulating it for Emergency Shutdown conditions (ESD) & Normal Shutdown conditions (NSD) to check if the compressor operating point crosses the surge limit line (SLL). A quick estimation method that uses dimensionless number called the inertia number can be used to check prior to the study, if a Hot gas bypass (a.k.a. Hot Recycle) is required in addition to an Anti-surge line (ASV or a.k.a Cold Recycle).
The document describes a process to separate permeate from biogas production containing ammonia, carbon dioxide, and water into 15% ammonia and purified wastewater.
A distillation column was designed using steady state calculations to determine operating parameters and size. Dynamic simulation was then used to model startup of the distillation column over 35 minutes to determine if the equipment could allow startup and normal operation.
The dynamic simulation showed the distillation column could reach its desired ammonia concentration and bottoms purity within 50-52 minutes of startup, demonstrating the feasibility of the steady state design when modeled dynamically.
Eksempler på anvendelse af (Computational Fluid Dynamics) CFD til kraftværker...R&R Consult
Præsentation af hvor vi har anvendt CFD til design, til bl.a. affaldsforbrændingsanlæg, biomassefyret anlæg, afsvovlingsanlæg (DeSOx) og til DeNOx (SCR)
Flere eksempler www.R-R-Consult.dk
Fired heaters and its auxiliaries are an essential component in the Chemical Process Industries (CPI). Fired heaters are primarily used to heat hydrocarbons. They are one of the major consumers of energy and hence, it is indispensable for such systems to have efficient operation.
Furnace Improvements Services has a specialist CFD team for modelling fired heater systems. We have developed best practices for each of the above cases and have successfully implemented various recommendations from CFD simulations.
Water Gas Shift & Hydrogen Purification Section FlowsheetGerard B. Hawkins
The document discusses different designs for the water gas shift and hydrogen purification sections of steam reforming plants. It describes the water gas shift reaction that converts carbon monoxide and water to carbon dioxide and hydrogen. It outlines designs using high-temperature shift catalyst followed by methanation or pressure swing adsorption to purify the hydrogen for ammonia and hydrogen plants. Newer hydrogen plant designs favor using a high-temperature shift catalyst followed directly by a pressure swing adsorption unit to produce 99.9% pure hydrogen.
This document provides formulas and examples for sizing vacuum receivers and pumps for vacuum thermoforming applications. It includes:
1) An equation for determining the size of a vacuum receiver based on mold volume, initial pressure, vacuum system pressure, and combined pressure.
2) An example calculation using the equation to determine a 54 gallon receiver is needed.
3) Equations for calculating the combined system pressure given an existing receiver size or determining the flow rate needed to achieve a given pump down time.
This document describes the development and validation of a mathematical model for a radial flow ammonia converter. The model equations account for material and energy balances across the three catalyst beds. Comparison to plant data from Abu Qir Fertilizers Company showed good agreement between the model and actual performance. The model is useful for optimizing operating conditions, evaluating catalyst performance over time, and determining the effects of adding a fourth catalytic bed.
Capacity Enhancement of Ammonia Production By The Revamping of Ammonia.
In this project, we find conversion and temperature profile of a two catalyst bed with one interbed heat exchanger ammonia converter and a three catalyst bed with two interbed heat exchanger ammonia converter both have radial flow by using a pseudo homogeneous two dimensional mathematical model on the basis of principle of conservation of mass and energy balance with the help of MATLAB pde solver.We conclude that a three catalyst bed ammonia converter give a higher conversion and lower pressure drop compare to the two catalyst bed ammonia converter for the same volume of catalyst bed and same amount of feed stock.
A QUICK ESTIMATION METHOD TO DETERMINE HOT RECYCLE REQUIREMENTS FOR CENTRIFUG...Vijay Sarathy
Turbomachinery Engineers often conduct studies to determine if a hot gas bypass is required for a given centrifugal compressor system. This would mean building a process model and simulating it for Emergency Shutdown conditions (ESD) & Normal Shutdown conditions (NSD) to check if the compressor operating point crosses the surge limit line (SLL). A quick estimation method that uses dimensionless number called the inertia number can be used to check prior to the study, if a Hot gas bypass (a.k.a. Hot Recycle) is required in addition to an Anti-surge line (ASV or a.k.a Cold Recycle).
The document describes a process to separate permeate from biogas production containing ammonia, carbon dioxide, and water into 15% ammonia and purified wastewater.
A distillation column was designed using steady state calculations to determine operating parameters and size. Dynamic simulation was then used to model startup of the distillation column over 35 minutes to determine if the equipment could allow startup and normal operation.
The dynamic simulation showed the distillation column could reach its desired ammonia concentration and bottoms purity within 50-52 minutes of startup, demonstrating the feasibility of the steady state design when modeled dynamically.
Eksempler på anvendelse af (Computational Fluid Dynamics) CFD til kraftværker...R&R Consult
Præsentation af hvor vi har anvendt CFD til design, til bl.a. affaldsforbrændingsanlæg, biomassefyret anlæg, afsvovlingsanlæg (DeSOx) og til DeNOx (SCR)
Flere eksempler www.R-R-Consult.dk
Fired heaters and its auxiliaries are an essential component in the Chemical Process Industries (CPI). Fired heaters are primarily used to heat hydrocarbons. They are one of the major consumers of energy and hence, it is indispensable for such systems to have efficient operation.
Furnace Improvements Services has a specialist CFD team for modelling fired heater systems. We have developed best practices for each of the above cases and have successfully implemented various recommendations from CFD simulations.
Water Gas Shift & Hydrogen Purification Section FlowsheetGerard B. Hawkins
The document discusses different designs for the water gas shift and hydrogen purification sections of steam reforming plants. It describes the water gas shift reaction that converts carbon monoxide and water to carbon dioxide and hydrogen. It outlines designs using high-temperature shift catalyst followed by methanation or pressure swing adsorption to purify the hydrogen for ammonia and hydrogen plants. Newer hydrogen plant designs favor using a high-temperature shift catalyst followed directly by a pressure swing adsorption unit to produce 99.9% pure hydrogen.
Microsoft PowerPoint - DEV of Dual FillingPRAN-RFL Group
The document describes a PET bottle blowing plant with the following key details:
1. The plant has a capacity of 450 bottles per minute and is model SBO 14.
2. It uses high pressure air between 35-38 bar and low pressure air at 7 bar to blow PET preforms into bottles using a dual system for carbonated soft drinks and hot fill applications.
3. The location is on the ground floor of the new CAN building and it consumes 324 kW of power plus an additional 30 kW for a total of 480 kW. It also uses chilled water at 12 degrees Celsius and 4 bar pressure.
Presentation on Calculation of Line Pack of Natural Gas Pipe using Aspen PLUS...Waqas Manzoor
This presentation demonstrates comparison of Line Pack calculation, using Aspen PLUS Dynamics and using Manual Calculations. The calculation results match closely. For the example problem discussed in the presentation. the line pack calculated by Aspen PLUS Dynamics is 35.988 MMSCF and the line pack calculated by using manual calculations is 34.969 MMSCF. The slight difference between the two may be attributed to the difference in computational method in Aspen PLUS Dynamics software.
The document discusses monitoring programs for critical equipment in ammonia plants to improve reliability and uptime. It outlines key performance indicators to monitor for various units, such as the primary reformer, secondary reformer, and shift converters. Monitoring parameters like temperatures, pressures, emissions and efficiencies can help identify problems early before catastrophic failures and keep the plant running optimally.
The document summarizes the design and analysis of an air-cooled heat exchanger for a 3-phase induction motor. It outlines specifications for the heat exchanger including air flow rates, temperatures, and heat exchange capacity. It then describes an 8-step process for the design including selecting materials, configuring piping, calculating heat transfer coefficients, and evaluating effectiveness. The scope of the project is defined as developing a prototype while considering losses, fan calculations, cost analysis, and testing iterations through graphical plotting.
Dr. Aborig Lecture- Chapter 3 natural gas processingamaborig
This document provides an overview of natural gas processing, including the key purposes and principles of gas processing. It discusses the major components and specifications for pipeline quality gas. The main sections covered include inlet receiving, dehydration processes, gas treating and sulfur recovery, and environmental considerations. Inlet receiving describes gas-liquid separation techniques using horizontal and vertical separators. Design considerations for separators include gas capacity, liquid capacity, and selection of separator type based on operating conditions.
Human: Thank you for the summary. Summarize the following document in 3 sentences or less:
[DOCUMENT]:
ENGI 8676 Design of Natural Gas Handling Equipment
ENGI 9120 Advanced Natural Gas Processing
Chapter 3
Natural Gas Processing
Finned-tube Heat Exchanger with Circular, Eliiptical and Rectangular Tubes wi...Hasibul Hasan Shovon
1) The study numerically investigates a finned-tube heat exchanger with circular, elliptical and rectangular tubes using water vapor as the working fluid.
2) Results show that heat exchanger designs with elliptical and rectangular tubes have higher heat transfer coefficients compared to the baseline circular tube design, with some designs also having lower pressure drops.
3) Temperature and pressure contours indicate better heat transfer and lower resistance for some modified designs compared to the baseline, especially at higher inlet velocities.
Combustion tutorial ( Eddy Break up Model) , CFDA.S.M. Abdul Hye
This document provides a tutorial for using STAR-CCM+ to simulate three combustion models: an idealized CAN gas turbine combustion chamber, a flame tube, and methane on platinum. It describes setting up simulations for each model, including importing geometries, defining materials and reactions, setting boundary conditions and solver parameters, and visualizing results. Specific steps are outlined for a simulation of propane combustion in a CAN chamber using an eddy break-up model, including generating a PPDF table and specifying initial conditions and stopping criteria.
R&R Consult and VODA A/S collaborated to redesign the secondary air supply and introduce water-cooled boiler walls for a waste heat incinerator at RenoSyd I/S. R&R Consult conducted CFD simulations to map the combustion process before and after the rebuild. The simulations included modeling of the fuel and primary air supply, secondary air distribution, heat transfer, and thermal radiation. The results were used to design an improved secondary air supply system and optimize the fuel/air distribution throughout the boiler domain. The model also helped verify that the boiler would meet environmental requirements for complete combustion.
4 b = 58 p 45 basic ur plant description 06.09.2021-1ameermudasar
The document provides an overview of the urea manufacturing process used at FFC plants in Pakistan. It describes the key stages of urea production, including CO2 compression, urea synthesis in the high pressure section, and decomposition and recovery in the medium and low pressure sections. The final stages involve vacuum concentration to increase the urea concentration to 99.7% for prilling, and a waste water treatment section. The document is intended as training material for staff on the urea production process.
Numerical Investigation of Finned-Tube Heat-exchanger with Circular, Elliptic...Hasibul Hasan Shovon
The document numerically investigates a finned-tube heat exchanger with circular, elliptical and rectangular tubes. It models the heat exchanger with 3 or 6 tubes in the configurations and analyzes heat transfer and pressure drop characteristics when air or water vapor flows over the tubes. The results show that modified configurations with mixed tube shapes can increase heat transfer by up to 10% compared to baseline designs, though they also increase pressure drop due to the higher frontal area of some tube shapes.
This document discusses the design of a Save Max boiler. It covers the customer inputs needed, the design procedure which involves determining the heat surface area and preparing the tube plate. Key design parameters that are calculated include tube pitch and thickness, furnace and wrapper drum plate thickness, stayed surface thickness, and shell thickness according to IBR regulations. Tube plate development must consider tube outer diameter, pitch, heat surface area, and gusset placement. Finally, detail drawings are prepared to communicate the design to production.
The document discusses pipe networks for water distribution systems. It describes:
1) Pipe networks can have multiple sources and sinks connected by an interconnected network of pipes. Computer solutions are used to model pipe networks.
2) Assumptions made in modeling pipe networks include each point having a single pressure and equal pressure changes along parallel paths. Conservation of mass is assumed at nodes.
3) Pipes can be modeled in parallel by applying the energy equation between nodes and adding pipe flows. Computer solutions are needed for networks with multiple loops.
Basic Unit Conversions for Turbomachinery Calculations Vijay Sarathy
Turbomachinery equipment like centrifugal pumps & compressors have their performance stated as a function of Actual volumetric flow rate [Q] & Head [m/bar]. The following tutorial describes how pump/compressor head can be expressed in energy terms as ‘kJ/kg’. Turbomachinery head expressed in kJ/kg describes, how many kJ of energy is required to compress 1 kg of gas for a given pressure ratio. The advantage of using energy terms to estimate absorbed power is that it is based on the amount of ‘mass’ compressed which is independent of pressure and temperature of a fluid.
Engineers often use softwares to perform gas compressor calculations to estimate compressor duty, temperatures, adiabatic & polytropic efficiencies, driver & cooler duty. In the following exercise, gas compressor calculations for a pipeline composition are shown as an example case study.
Heat exchangers transfer thermal energy between two or more fluids at different temperatures. They are classified based on their transfer process, geometry, heat transfer mechanism, and flow arrangement. Shell-and-tube heat exchangers consist of a set of tubes in a shell container and are the most important type, used across many industries. Their design involves calculating the heat transfer rate, selecting appropriate materials and geometry, and ensuring optimal fluid velocities and pressure drops within design limits.
Heat exchangers transfer heat from one medium to another and come in many designs. Shell and tube heat exchangers consist of tubes bundled together within a shell and are commonly used for high pressure and temperature applications. Plate heat exchangers use thin, stacked plates to transfer heat efficiently in a compact space. Selection of the appropriate heat exchanger design considers factors like pressure limits, thermal performance, materials, and cost. Heat exchangers play an important role in many industrial processes like ammonia production.
Combustion and dry low nox 2.6 dln systemFaisal Nadeem
I have explained the combustion and DLN2.6, dry low nox 2.6 + with better understanding. Trainings from Experts and my personal experience on gas turbines helps me understand the DLN 2.6 system. I hope trainee from Power Plants will like the slide. its good work of research for young trainees at Power Plants
This document compares the performance of three controllers - Smith predictor sliding mode controller (SMC), proportional integral derivative (PID) controller, and predictive sliding mode controller (PSMC) for controlling main steam pressure in a coal-fired power plant boiler. It presents a first order plus time delay model of the boiler system. A Smith predictor structure is used to address time delay, combined with SMC to overcome model mismatches. Simulation results show the SMC with Smith predictor provides better performance and robustness than PID control for set point changes. The PSMC further improves control of process output and control signals.
Vapour compression system, is a closed-loop system that uses a liquid refrige...ShivamGupta913790
is a closed-loop system that uses a liquid refrigerant that's alternately compressed and expanded through four stages, changing it from a liquid to a vapor.
Microsoft PowerPoint - DEV of Dual FillingPRAN-RFL Group
The document describes a PET bottle blowing plant with the following key details:
1. The plant has a capacity of 450 bottles per minute and is model SBO 14.
2. It uses high pressure air between 35-38 bar and low pressure air at 7 bar to blow PET preforms into bottles using a dual system for carbonated soft drinks and hot fill applications.
3. The location is on the ground floor of the new CAN building and it consumes 324 kW of power plus an additional 30 kW for a total of 480 kW. It also uses chilled water at 12 degrees Celsius and 4 bar pressure.
Presentation on Calculation of Line Pack of Natural Gas Pipe using Aspen PLUS...Waqas Manzoor
This presentation demonstrates comparison of Line Pack calculation, using Aspen PLUS Dynamics and using Manual Calculations. The calculation results match closely. For the example problem discussed in the presentation. the line pack calculated by Aspen PLUS Dynamics is 35.988 MMSCF and the line pack calculated by using manual calculations is 34.969 MMSCF. The slight difference between the two may be attributed to the difference in computational method in Aspen PLUS Dynamics software.
The document discusses monitoring programs for critical equipment in ammonia plants to improve reliability and uptime. It outlines key performance indicators to monitor for various units, such as the primary reformer, secondary reformer, and shift converters. Monitoring parameters like temperatures, pressures, emissions and efficiencies can help identify problems early before catastrophic failures and keep the plant running optimally.
The document summarizes the design and analysis of an air-cooled heat exchanger for a 3-phase induction motor. It outlines specifications for the heat exchanger including air flow rates, temperatures, and heat exchange capacity. It then describes an 8-step process for the design including selecting materials, configuring piping, calculating heat transfer coefficients, and evaluating effectiveness. The scope of the project is defined as developing a prototype while considering losses, fan calculations, cost analysis, and testing iterations through graphical plotting.
Dr. Aborig Lecture- Chapter 3 natural gas processingamaborig
This document provides an overview of natural gas processing, including the key purposes and principles of gas processing. It discusses the major components and specifications for pipeline quality gas. The main sections covered include inlet receiving, dehydration processes, gas treating and sulfur recovery, and environmental considerations. Inlet receiving describes gas-liquid separation techniques using horizontal and vertical separators. Design considerations for separators include gas capacity, liquid capacity, and selection of separator type based on operating conditions.
Human: Thank you for the summary. Summarize the following document in 3 sentences or less:
[DOCUMENT]:
ENGI 8676 Design of Natural Gas Handling Equipment
ENGI 9120 Advanced Natural Gas Processing
Chapter 3
Natural Gas Processing
Finned-tube Heat Exchanger with Circular, Eliiptical and Rectangular Tubes wi...Hasibul Hasan Shovon
1) The study numerically investigates a finned-tube heat exchanger with circular, elliptical and rectangular tubes using water vapor as the working fluid.
2) Results show that heat exchanger designs with elliptical and rectangular tubes have higher heat transfer coefficients compared to the baseline circular tube design, with some designs also having lower pressure drops.
3) Temperature and pressure contours indicate better heat transfer and lower resistance for some modified designs compared to the baseline, especially at higher inlet velocities.
Combustion tutorial ( Eddy Break up Model) , CFDA.S.M. Abdul Hye
This document provides a tutorial for using STAR-CCM+ to simulate three combustion models: an idealized CAN gas turbine combustion chamber, a flame tube, and methane on platinum. It describes setting up simulations for each model, including importing geometries, defining materials and reactions, setting boundary conditions and solver parameters, and visualizing results. Specific steps are outlined for a simulation of propane combustion in a CAN chamber using an eddy break-up model, including generating a PPDF table and specifying initial conditions and stopping criteria.
R&R Consult and VODA A/S collaborated to redesign the secondary air supply and introduce water-cooled boiler walls for a waste heat incinerator at RenoSyd I/S. R&R Consult conducted CFD simulations to map the combustion process before and after the rebuild. The simulations included modeling of the fuel and primary air supply, secondary air distribution, heat transfer, and thermal radiation. The results were used to design an improved secondary air supply system and optimize the fuel/air distribution throughout the boiler domain. The model also helped verify that the boiler would meet environmental requirements for complete combustion.
4 b = 58 p 45 basic ur plant description 06.09.2021-1ameermudasar
The document provides an overview of the urea manufacturing process used at FFC plants in Pakistan. It describes the key stages of urea production, including CO2 compression, urea synthesis in the high pressure section, and decomposition and recovery in the medium and low pressure sections. The final stages involve vacuum concentration to increase the urea concentration to 99.7% for prilling, and a waste water treatment section. The document is intended as training material for staff on the urea production process.
Numerical Investigation of Finned-Tube Heat-exchanger with Circular, Elliptic...Hasibul Hasan Shovon
The document numerically investigates a finned-tube heat exchanger with circular, elliptical and rectangular tubes. It models the heat exchanger with 3 or 6 tubes in the configurations and analyzes heat transfer and pressure drop characteristics when air or water vapor flows over the tubes. The results show that modified configurations with mixed tube shapes can increase heat transfer by up to 10% compared to baseline designs, though they also increase pressure drop due to the higher frontal area of some tube shapes.
This document discusses the design of a Save Max boiler. It covers the customer inputs needed, the design procedure which involves determining the heat surface area and preparing the tube plate. Key design parameters that are calculated include tube pitch and thickness, furnace and wrapper drum plate thickness, stayed surface thickness, and shell thickness according to IBR regulations. Tube plate development must consider tube outer diameter, pitch, heat surface area, and gusset placement. Finally, detail drawings are prepared to communicate the design to production.
The document discusses pipe networks for water distribution systems. It describes:
1) Pipe networks can have multiple sources and sinks connected by an interconnected network of pipes. Computer solutions are used to model pipe networks.
2) Assumptions made in modeling pipe networks include each point having a single pressure and equal pressure changes along parallel paths. Conservation of mass is assumed at nodes.
3) Pipes can be modeled in parallel by applying the energy equation between nodes and adding pipe flows. Computer solutions are needed for networks with multiple loops.
Basic Unit Conversions for Turbomachinery Calculations Vijay Sarathy
Turbomachinery equipment like centrifugal pumps & compressors have their performance stated as a function of Actual volumetric flow rate [Q] & Head [m/bar]. The following tutorial describes how pump/compressor head can be expressed in energy terms as ‘kJ/kg’. Turbomachinery head expressed in kJ/kg describes, how many kJ of energy is required to compress 1 kg of gas for a given pressure ratio. The advantage of using energy terms to estimate absorbed power is that it is based on the amount of ‘mass’ compressed which is independent of pressure and temperature of a fluid.
Engineers often use softwares to perform gas compressor calculations to estimate compressor duty, temperatures, adiabatic & polytropic efficiencies, driver & cooler duty. In the following exercise, gas compressor calculations for a pipeline composition are shown as an example case study.
Heat exchangers transfer thermal energy between two or more fluids at different temperatures. They are classified based on their transfer process, geometry, heat transfer mechanism, and flow arrangement. Shell-and-tube heat exchangers consist of a set of tubes in a shell container and are the most important type, used across many industries. Their design involves calculating the heat transfer rate, selecting appropriate materials and geometry, and ensuring optimal fluid velocities and pressure drops within design limits.
Heat exchangers transfer heat from one medium to another and come in many designs. Shell and tube heat exchangers consist of tubes bundled together within a shell and are commonly used for high pressure and temperature applications. Plate heat exchangers use thin, stacked plates to transfer heat efficiently in a compact space. Selection of the appropriate heat exchanger design considers factors like pressure limits, thermal performance, materials, and cost. Heat exchangers play an important role in many industrial processes like ammonia production.
Combustion and dry low nox 2.6 dln systemFaisal Nadeem
I have explained the combustion and DLN2.6, dry low nox 2.6 + with better understanding. Trainings from Experts and my personal experience on gas turbines helps me understand the DLN 2.6 system. I hope trainee from Power Plants will like the slide. its good work of research for young trainees at Power Plants
This document compares the performance of three controllers - Smith predictor sliding mode controller (SMC), proportional integral derivative (PID) controller, and predictive sliding mode controller (PSMC) for controlling main steam pressure in a coal-fired power plant boiler. It presents a first order plus time delay model of the boiler system. A Smith predictor structure is used to address time delay, combined with SMC to overcome model mismatches. Simulation results show the SMC with Smith predictor provides better performance and robustness than PID control for set point changes. The PSMC further improves control of process output and control signals.
Vapour compression system, is a closed-loop system that uses a liquid refrige...ShivamGupta913790
is a closed-loop system that uses a liquid refrigerant that's alternately compressed and expanded through four stages, changing it from a liquid to a vapor.
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
Dual chamber vacuum furnace for Low Pressure Carburizing (LPC) and High Press...ALD Vacuum Systems Inc.
Dual vacuum furnaces with separated heating and cooling processes are providing several advantages when compared to single chamber vacuum furnaces. This includes faster heating up, less energy consumption, more quenching severity and less maintenance. Accordingly a new, “second
generation” of dual vacuum furnace for low pressure carburizing and high pressure gas quenching, DualTherm®, was developed using proven technologies from the ModulTherm® series of vacuum furnace systems.
The first furnace was recently installed at a commercial heat treater and is now in three-shift-operation.
Minimising emissions, maximising alternative fuelsA TEC Group
Dr. Stefan Kern, A TEC Production and Services GmbH, details the conversion of the kiln at Lafarge Retznei and shows how an optimised calciner design allowed for 100% alternative fuel usage.
"Minimising emissions, maximising alternative fuels". Article published on World Cement Magazine, edition June 2022.
Application of Electrical Heating in Enhanced Oil Recovery(EOR)Saeid Javidi
This document summarizes electrical heating as a technique for heavy oil recovery. It discusses how electrical heating works by generating heat near the wellbore to reduce oil viscosity and remove thermal skin effects. This allows improved production rates with lower costs compared to steam injection. The key components of an electrical heating system and operating principles are described. Simulation results show how electrical heating can remove visco-skin and increase production threefold. Operating strategies like maintaining electrode temperatures below 100°C are discussed. In conclusion, electrical heating is an effective wellbore stimulation process for increasing heavy oil productivity.
This document summarizes the use of fuzzy logic applications in a 500 MW power station. Specifically, it proposes fuzzy logic systems for soot blowing optimization and drum level control. For soot blowing optimization, a fuzzy rule-based system estimates the cleanliness factor of boiler sections to determine the correct soot blowing scheme. For drum level control, two fuzzy strategies are proposed: 1) Using fuzzy logic rules to vary the PID controller gains based on error and error derivative. 2) Varying the drum level setpoint based on fuzzy logic rules. Simulation results show the fuzzy approaches improve dynamic and steady-state performance for both control problems.
This document summarizes the use of fuzzy logic applications in a 500 MW power station. Specifically, it proposes fuzzy logic systems for soot blowing optimization and drum level control. For soot blowing optimization, a fuzzy rule-based system estimates the cleanliness factor of boiler sections to determine the correct soot blowing scheme. For drum level control, two fuzzy strategies are proposed: 1) Using fuzzy logic rules to vary the PID controller gains based on error and error derivative. 2) Varying the drum level setpoint based on fuzzy logic rules. Simulation results show the fuzzy approaches improve dynamic and steady-state performance for both control problems.
This document discusses the use of an "over-conductivity function" to model the natural cooling process in steam turbines. It summarizes previous research on modeling natural cooling and validates the over-conductivity approach on three additional turbines. The over-conductivity function replaces complex fluid dynamics with an equivalent higher conductivity, allowing faster simulations while maintaining 15-18°C accuracy compared to temperature measurements during natural cooling periods of over 100 hours.
This document summarizes how modern computer dynamic analysis and detailed evaluations can yield significant savings in both weight and cost of flare and relief systems compared to traditional steady state calculation methods. It provides examples showing that dynamic simulation can predict substantially lower relief loads for vessels under fire or distillation column upsets. It also illustrates how dynamic flow analysis of flare header designs allows additional relief sources to be accommodated without exceeding pressure limits, avoiding the need for larger and more expensive systems.
Design of Heat Exchanger Network for VCM Distillation Unit Using Pinch Techno...IJERA Editor
In process industries, heat exchanger networks represent an important part of the plant structure. The purpose of the networks is to maximize heat recovery, thereby lowering the overall plant costs. In process industries, during operation of any heat exchanger network (HEN), the major aim is to focus on the best performance of the network As in present condition of fuel crises is one of the major problem faced by many country & industrial utility is majorly depend on this. There is technique called process integration which is used for integrate heat within loop so optimize the given process and minimize the heating load and cooling load .In the present study of heat integration on VCM (vinyl chloride monomer) distillation unit, Heat exchanger network (HEN) is designed by using Aspen energy analyzer V8.0 software. This software implements a methodology for HEN synthesis with the use of pinch technology. Several heat integration networks are designed with different ΔT min and total annualized cost compared to obtain the optimal design. The network with a ΔT min of 90C is the most optimal where the largest energy savings are obtained with the appropriate use of utilities (Save 15.3764% for hot utilities and 47.52% for cold utilities compared with the current plant configuration). Percentage reduction in total operating cost is 18.333%. From calculation Payback Period for new design is 3.15 year. This save could be done through a plant revamp, with the addition of two heat exchangers. This improvement are done in the process associated with this technique are not due to the use of advance unit operation, but to the generation of heat integration scheme. The Pinch Design Method can be employed to give good designs in rapid time and with minimum data.
CENTRIFUGAL COMPRESSOR SETTLE OUT CONDITIONS TUTORIALVijay Sarathy
Centrifugal Compressors are a preferred choice in gas transportation industry, mainly due to their ability to cater to varying loads. In the event of a compressor shutdown as a planned event, i.e., normal shutdown (NSD), the anti-surge valve is opened to recycle gas from the discharge back to the suction (thereby moving the operating point away from the surge line) and the compressor is tripped via the driver (electric motor or Gas turbine / Steam Turbine). In the case of an unplanned event, i.e., emergency shutdown such as power failure, the compressor trips first followed by the anti-surge valve opening. In doing so, the gas content in the suction side & discharge side mix.
Therefore, settle out conditions is explained as the equilibrium pressure and temperature reached in the compressor piping and equipment volume following a compressor shutdown
This document proposes a cascade model predictive control scheme using generalized predictive control (GPC) for both the inner and outer loops to control boiler drum level. Cascade GPC can effectively reject measured and unmeasured disturbances to maintain drum level at a constant load. It can also handle non-minimum phase characteristics and system constraints in both loops. Simulation results show cascade GPC provides better performance than well-tuned cascade PID controllers. The method was also implemented on a 75-MW boiler plant with improved results over conventional control schemes.
This document discusses performance monitoring for gas turbines. It begins by explaining that performance monitoring is critical for maximizing efficiency from gas turbines and processes, though it is less common than mechanical condition monitoring. It then provides details on:
- How performance monitoring systems work and the types of information they can provide.
- The factors that can affect gas turbine performance, both naturally from ambient conditions and loads, as well as from equipment degradation.
- The importance of differentiating between performance changes from natural causes versus degradation when analyzing data from monitoring systems.
- The distinction between recoverable and non-recoverable degradation, and how performance and mechanical condition monitoring can be used together to better diagnose issues.
The document discusses the benefits of standby time in adsorption dehydration processes. It describes how molecular sieves are used to dehydrate natural gas and how their capacity declines over cycles due to loss of structure. Having excess regeneration capacity, or standby time, allows operators to reduce cycle times and extend the life of molecular sieves. The document presents a case study where performance testing revealed capacity would decline faster than designed. Using standby time by reducing cycle times allowed the unit to operate for longer than the planned 3 years before recharge.
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Similar to Improved Lime Mud Kiln Control System Tappi Peers Paper 16 (20)
Improved Lime Mud Kiln Control System Tappi Peers Paper 16
1. Improve Lime Mud Kiln Operation
By Controlling Mud Moisture Using an Inside-The-Dryer Moisture Sensor
John Robinson
Roger Douglas
Drying Technology, Inc.
ABSTRACT
A Lime Mud Kiln consists of three sequential unit operations: drying, heating, and calcining. Traditionally, two
control loops have been used: A hot end temperature (het) loop maintains the proper calcining temperature, and a
cold end temperature (cet) loop is used, perhaps unwittingly, as a non-theoretical mud moisture (mc) sensing and
control loop. This cet loop is similar to the flawed, non-theoretical exhaust temperature mc sensing and control loop
used for controlling the mc of products being dried using industrial dryers, including counter-current rotary dryers.
Fortunately, this flawed mc sensing and control problem has been solved for industrial dryer applications; therefore,
it is proposed as a replacement for the old (cet) loop in a new lime mud kiln control system. Based on the analogous
relationship between a cet loop and a delta t loop = (het – cet) = delta t loop, if the delta t loop replaces the cet loop
on a kiln, the drying zone will be controlled to a constant length with at least 30% less variation in length, and this
will in turn control the calcining zone to a constant length with at least 30% less variation in length. Therefore, the
delta t loop will control the length (time) component and the het loop will control the temperature component of the
time-temperature parameter necessary for producing a superior finished lime
INTRODUCTION
A Lime Mud Kiln may be described simply as a series of three unit operations: drying, heating, and calcining as
illustrated by figure (1).
Figure (1) – Three Unit Operation Zones in a Lime Mud Kiln
Although simply described by figure (1), there are numerous problems involved in successfully operating a kiln.
Since drying is the first of this series of unit operations, it is reasonable to conclude that if the moisture (mc) of the
mud leaving the drying zone is not properly controlled, the drying zone length will vary for each change in the
evaporative load. Such variations will be transmitted as a change in length of the heating zone as well as a similar
change in the calcining zone length. Changes in the calcining zone length cause carbonate content variations in the
finished lime that are not detected until the finished lime is later sampled. In addition, it is reasonable to assume that
2. these uncontrolled evaporative load swings contribute to the formation of water-related rings and dusting
occurrences.
ANALOGOUS OPERATION OF ROTARY DRYERS AND KILNS
The cold end temperature (cet) loop of a kiln is used to control the mc of the mud exiting the drying zone of a kiln;
likewise, the exhaust temperature from a counter-current rotary dryer has traditionally been used to control the mc of
products exiting rotary dryers. Figure (2) illustrates this analogy:
Figure (2) - Drying Similarity of a Counter-Current Rotary Dryer
and Drying Zone of a Lime Mud Kiln
Although these two non-theoretical methods control in the right direction, as soon as an evaporative load enters the
dryer or kiln, the old exhaust temperature or cet setpoint is no longer valid for the new operating conditions, and a
precise, mathematical method has not been available for re-calculating a new setpoint. Consequently, both industrial
drying and lime mud kilns use the same ineffective mc sensing and control method.
TRADITIONAL DRYER CONTROL PROBLEMS
There are three main problems that prevent traditional mc sensing and control from being effective: (1) lack of
timely and reliable mc data upon which to base a control decision; (2) lack of a method for precisely re-calculating
the process variable setpoint in order to maintain the target mc; and (3) lack of a simple, non-problematic, and
relatively inexpensive evaporative load sensor.
Fortunately, these problems were solved1,2
by the derivation of the general, moisture control model:
MC = K1(ΔT)p
– K2/Sq
This model enables prediction and control of the mc of a product exiting a rotary dryer by relating it to the
temperature drop (ΔT) of hot air after contact with a wet product, and the evaporative load, production rate, or dryer
speed (S). The model provides the following solutions for the three problems with traditional mc sensing and
control: (1) An inside-the-dryer mc soft sensor, consisting of two ordinary temperature sensors, that is rugged,
reliable, does not drift, and does not require re-calibration; (2) The capability for re-calculating the process variable
(ΔT) setpoint needed to maintain the target mc following evaporative load changes entering the dryer; and (3) A
simple, inexpensive, non-problematic, evaporative load soft sensor.
When these three solutions are incorporated into a mc sensing and control system, the target mc is maintained with
at least 30% less mc variation than that achieved using traditional mc sensing & control methods. The model
applies to such direct dryer-types as rotary, flash, spray, belt, fluid-bed, batch, and to some indirect dryers and batch
dryers.
3. TRADITIONAL LIME MUD KILN CONTROL SYSTEM
Traditionally, two Proportional – Integral – Derivative (PID) loops have been used for controlling a kiln: The hot
end temperature (het) loop maintains the proper calcining temperature at the front end (exit) of the kiln and the cold
end temperature (cet) loop is used to control the mud mc using the cet setpoint as a non-theoretical surrogate for mc.
As previously stated, the cet loop is analogous to the exhaust temperature control method for industrial dryers;
therefore, it suffers from the same three problems listed above for rotary dryer mc control. Consequently, use of this
ineffective, non-theoretical cet loop control method for controlling mud mc exiting the drying zone allows the
drying zone length to vary, and also the calcining zone to vary in length, thus causing over and under-calcined lime
variations. In addition, the kiln temperature profile is distorted for each evaporative load disturbance. Its effect on
the finished lime will be discussed later.
TECHNOLOGY TRANSFER
If the drying zone of a kiln is analogous to a counter-current rotary dryer, and the three control solutions are working
exceedingly well on industrial rotary dryers, it appears logical to assume that this improved mc control system
would be effective in sensing and controlling mud mc exiting the drying zone of a kiln, thus controlling the drying
zone length as well. Since this improved method has consistently reduced mc variation at least 30% during control
of rotary dryers, it has the potential for reducing variations in a kiln drying zone length (time) by 30%. It is also
reasonable to assume that variations in the drying zone will be transmitted through the kiln to produce similar
variations in the calcining zone length. Consequently, by properly controlling the mud mc exiting the drying zone,
the time component of the time-temperature parameter is determined, and when coupled with the het loop, that
controls the temperature component of the time-temperature parameter, a more effective lime mud kiln control
system is made available. It is not unreasonable to expect that the carbonate content would be reduced by 30%. For
example, if the present carbonate content were 3.5%, it would be reduced to 2.5%. In addition, a 30% reduction in
mc variation should reduce or eliminate water-related ring formations, dusting occurrences, and perhaps reduce re-
carbonation and sodium vaporization by reducing het excursions.
APPLICATION OF THE DELTA T CONTROL TO A LIME MUD KILN
Transformation of the existing two-loop control system is easily accomplished, usually without hardware addition
by changing the cet loop to a delta t loop simply by subtracting the cet from the het (het – cet) = ΔT loop. The het
loop remains unchanged. An additional benefit of subtracting the cet and the het is that it eliminates (subtracts) het
fluctuations that are normally transmitted to the cet loop and possibly eliminates the interaction present in the
traditional two-loop kiln control system. Figure (3) illustrates the possible effect of error reduction by subtracting the
two loops (het + noise) – (cet + noise) = (het – cet):
Figure (3) – Shows Reduction in Noise by Subtracting Loops
Figure (4) subtracts the cet from the het to give the improved delta t loop.
4. Figure (4) – The Improved Delta T Loop
Figure (5) depicts the new kiln control system that combines the het loop with the delta t loop for internal drying:
Figure (5) – Combined Two-Loop Delta T Moisture Control System
for Internal Mud Drying
This new kiln control system should operate much better on an external dryer as illustrated by Figure (6).
Figure (6) Two-Loop Delta T Moisture Control System
for External Mud Dryer
NEW LIME KILN CONTROL OPERATION
Assuming the kiln is operating at steady-state, an evaporative load increase entering the kiln causes the delta t value
(het – cet) to increase. The Delta T loop control compares the actual delta t value to the delta t setpoint that produces
the target mc at the current operating conditions. The difference (error) is used to pull more air from the front end to
bring the delta t back to the old setpoint value. However, since the evaporative load and the air flow through the
kiln have increased, the old operating condition setpoint will not produce the target mc. It must be re-calculated
using proprietary means as illustrated by figure (7); otherwise, the mud will not be dried properly.
Figure (7) – Re-calculating a New Delta T Setpoint
5. NEW KILN CONTROL OPERATING EXPERIENCE
A USDOE energy grant financed a trial installation of the patented, award-winning Delta T on No. 3 kiln at Temple-
Inland’s paper mill at Evadale, TX. It ran for approximately two months during November of 1995 – December
1995. The kiln was a 1950’s era kiln and was scheduled to be replaced shortly after the trial. The purpose of the trial
was to evaluate combining the two loops. The scope of the trial did not include evaluating its effectiveness in
reducing carbonate content; however, it did show a 4% reduction in unit energy consumption. Energy savings
would have been higher if secondary air had been available at high production rates to keep the oxygen level high
enough to maintain TRS within limits. TRS was controlled by reducing the fuel rate at the expense of higher
carbonate content in the finished lime. Overall, the operation was quite smooth over the approximately two months
run.
RESULTS & CONCLUSIONS
This new and improved lime mud kiln control system treats the lime kiln as a series of unit operations with the final
operation a calcining reactor that is best controlled using the het loop to maintain the calcining temperature, and the
new delta t loop to control the time component of the time-temperature parameter. Thus, both components of the
time-temperature parameter are available for gaining better control of the kiln. Since mc variations are reduced 30%
by an analogous counter-current, industrial rotary dryer application, a 30% reduction in calcining time variation
should be realized. In addition, improved control of mud mc should reduce or eliminate occurrences of water-
related rings, dusting, and possibly reduce the tendency for re-carbonation of calcium oxide, or sodium vaporization
as a result of fewer high temperature excursions. This new and improved kiln control system, normally a software-
only solution, does not require kiln downtime, and should be much simpler to operate.
LITERATURE CITED
1. Robinson, J.W., “A New Drying Model,” Proc. North American Drying Symposium, Mississippi Forest Products
Utilization Lab., MS., State, MS, pp. 78 – 84, (Nov. 27 – 28, 1984).
2. Robinson, J.W., Improve Dryer Control, CEP, Vol. 88, No. 12, pp. 28-33, (Dec. 1992).
APPENDIX
Awards
National Forest Products Association/American Paper Institute Environmental and Energy Innovation Award for
1986.
US Department of Energy – Energy Innovation Award for 1985.
The State of Texas – Energy Innovation Award for 1985.
The Texas Forestry Association – Award of Merit in 1984.
Inventions and Innovation grant from Office of Industrial Technologies, USDOE, to extend DELTA T technology to
four industries 1992.
Patents
US Patent No. 4.701,857, Oct. 20, 1987, Method and Apparatus for Controlling Dryers for Wood Products, Fabrics,
Paper and Pulp.
US Patent No. 4,777, 604, Oct. 11, 1988, Method and Apparatus for Controlling Batch Dryers.