IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
IRJET- Controlling A Multi-Evaporator Refrigeration System that Uses Cuo/R134...IRJET Journal
This document discusses controlling a refrigeration system with multiple evaporators using a CuO/R134a nanofluid as the refrigerant. It first experimentally investigates how the evaporator heat transfer coefficient is affected by heat flux, nanofluid mass flux, and nanoparticle concentration. The heat transfer coefficient increased with heat and mass fluxes and peaked at a 0.5% nanoparticle concentration. Two correlations were developed to relate heat transfer to these parameters. It then modifies the system to add a second evaporator and uses the experimental results to control heat and mass fluxes to control the heat transfer coefficient and evaporator behavior. This approach could allow controlling multiple evaporators with one compressor in future work.
Meet the demanding needs of high-purity water measurements and high-acid cation exchange applications with the Thermo Scientific™ Orion™ 2111XP Sodium Analyzer. This system offers unmatched reliability in analyzing critical sample streams throughout the power/steam generation and industrial water industry. It is an all-in-one system from one of the most trusted names in sodium monitoring.
For efficient control of combustion and drying processes
Simultaneous or as individual measurement: the GM35 gas analyzer measures CO2, H2O and CO, or N2O, as well temperature and pressure – and it does this reliably, quickly, and economically. As an in-situ gas analyzer, the GM35 detects these gas components directly in the gas stream without gas sampling. Reliability, precision, and short response time of the GM35 offer a key advantage for efficient control loops in all CO and CO2-generating processes.
Claus Sulfur Recovery Tail Gas Applying 100 Million Hours of Operational Time...Ives Equipment
The measurement of H2S/SO2 in Claus sulfur recovery unit (SRU) tail gas has been adequately addressed by UV spectroscopy for over 40 years. Reliability of the analytical principle was established in the first generation of analyzers and in the second generation sample handling was improved to the point where automatic control if not universal is at least considered the norm. With a deep understanding of the process and a population of 1,100 second generation analyzers it was possible in the third generation to address failure modes external to the analyzer. Reliability is not limited to the analyzer / sample system; it extends to the process and contains elements of health and safety. Analyzer professionals are compelled to look beyond what we consider our "deliverables", to address abnormal operations and bad piping design. The paper combines extensive feedback from analyzer professionals and a survey of sulfur recovery operators to address the external failure modes. Looking back on 100 million hours of operational time and one year of field testing the third generation analyzer the paper discusses reliability as viewed by the real end use customer; Operations.
Experimental Study and CFD Analysis of Thermal Performance Improvement of Car...IRJET Journal
This document summarizes an experimental study and CFD analysis of using MgO/water nanofluid to improve the thermal performance of a car radiator. Experiments were conducted to test different volume fractions of MgO/water nanofluid and measure its thermal properties and heat transfer rate in the radiator. CFD simulations were also performed to validate the experimental temperature distributions. The results showed that using MgO/water nanofluid as the coolant led to higher heat transfer rates and outlet temperatures in the radiator compared to using just water, with enhancements of up to 70% observed, and the performance increased with higher nanoparticle volume fractions.
Vasthi Engineers are most popular Manufacturing industries in india. we are Supplying Dew Point Meters, Gas Analyzers and Gas Detectors for customer world wide.
For more details visit->http://www.vasthi.com/gas-analyzers/
This document provides a nitrogen purging procedure for repairing a 16" gas pipeline between UTUE KP and UBIT PP in Nigeria. It outlines the objectives, scope of work, safety considerations, equipment needs, and step-by-step work procedures. The key steps include isolating and depressurizing the pipeline, installing nitrogen tie-in points, purging the line with nitrogen in cycles until gas concentration drops below 5% LEL, recording purge results, and demobilizing equipment. The procedure is intended to remove combustible gases and oxygen from the pipeline to allow for safe repair work.
Thermo catalytic decomposition of methane over Pd/AC and Pd/CB catalysts for ...IJERA Editor
Hydrogen production studies have been carried using Thermo Catalytic Decomposition (TCD) Unit. Thermo catalytic decomposition of methane is an attractive route for COx free production of hydrogen required in fuel cells. Although metal based catalysts produce hydrogen at low temperatures, carbon formed during methane decomposition reaction rapidly deactivates the catalyst. The present work compares the results of 10 wt% Pd supported on commercially available activated carbon and carbon black catalysts (samples coded as Pd10/AC and Pd10/CB respectively) for methane decomposition reaction. Hydrogen has been produced by thermo catalytic decomposition of methane at 1123K and Volume Hourly Space Velocity (VHSV) of 1.62 L/h g on the activity of both the catalysts has been studied. XRD of the above catalysts revealed, moderately crystalline peaks of Pd which may be responsible for the increase in catalytic life and formation of carbon fibers. Also during life studies (850°C and 54 sccm of methane) it has been observed that the activity of carbon black is sustainable for a longer time compared to that of activated carbon.
IRJET- Controlling A Multi-Evaporator Refrigeration System that Uses Cuo/R134...IRJET Journal
This document discusses controlling a refrigeration system with multiple evaporators using a CuO/R134a nanofluid as the refrigerant. It first experimentally investigates how the evaporator heat transfer coefficient is affected by heat flux, nanofluid mass flux, and nanoparticle concentration. The heat transfer coefficient increased with heat and mass fluxes and peaked at a 0.5% nanoparticle concentration. Two correlations were developed to relate heat transfer to these parameters. It then modifies the system to add a second evaporator and uses the experimental results to control heat and mass fluxes to control the heat transfer coefficient and evaporator behavior. This approach could allow controlling multiple evaporators with one compressor in future work.
Meet the demanding needs of high-purity water measurements and high-acid cation exchange applications with the Thermo Scientific™ Orion™ 2111XP Sodium Analyzer. This system offers unmatched reliability in analyzing critical sample streams throughout the power/steam generation and industrial water industry. It is an all-in-one system from one of the most trusted names in sodium monitoring.
For efficient control of combustion and drying processes
Simultaneous or as individual measurement: the GM35 gas analyzer measures CO2, H2O and CO, or N2O, as well temperature and pressure – and it does this reliably, quickly, and economically. As an in-situ gas analyzer, the GM35 detects these gas components directly in the gas stream without gas sampling. Reliability, precision, and short response time of the GM35 offer a key advantage for efficient control loops in all CO and CO2-generating processes.
Claus Sulfur Recovery Tail Gas Applying 100 Million Hours of Operational Time...Ives Equipment
The measurement of H2S/SO2 in Claus sulfur recovery unit (SRU) tail gas has been adequately addressed by UV spectroscopy for over 40 years. Reliability of the analytical principle was established in the first generation of analyzers and in the second generation sample handling was improved to the point where automatic control if not universal is at least considered the norm. With a deep understanding of the process and a population of 1,100 second generation analyzers it was possible in the third generation to address failure modes external to the analyzer. Reliability is not limited to the analyzer / sample system; it extends to the process and contains elements of health and safety. Analyzer professionals are compelled to look beyond what we consider our "deliverables", to address abnormal operations and bad piping design. The paper combines extensive feedback from analyzer professionals and a survey of sulfur recovery operators to address the external failure modes. Looking back on 100 million hours of operational time and one year of field testing the third generation analyzer the paper discusses reliability as viewed by the real end use customer; Operations.
Experimental Study and CFD Analysis of Thermal Performance Improvement of Car...IRJET Journal
This document summarizes an experimental study and CFD analysis of using MgO/water nanofluid to improve the thermal performance of a car radiator. Experiments were conducted to test different volume fractions of MgO/water nanofluid and measure its thermal properties and heat transfer rate in the radiator. CFD simulations were also performed to validate the experimental temperature distributions. The results showed that using MgO/water nanofluid as the coolant led to higher heat transfer rates and outlet temperatures in the radiator compared to using just water, with enhancements of up to 70% observed, and the performance increased with higher nanoparticle volume fractions.
Vasthi Engineers are most popular Manufacturing industries in india. we are Supplying Dew Point Meters, Gas Analyzers and Gas Detectors for customer world wide.
For more details visit->http://www.vasthi.com/gas-analyzers/
This document provides a nitrogen purging procedure for repairing a 16" gas pipeline between UTUE KP and UBIT PP in Nigeria. It outlines the objectives, scope of work, safety considerations, equipment needs, and step-by-step work procedures. The key steps include isolating and depressurizing the pipeline, installing nitrogen tie-in points, purging the line with nitrogen in cycles until gas concentration drops below 5% LEL, recording purge results, and demobilizing equipment. The procedure is intended to remove combustible gases and oxygen from the pipeline to allow for safe repair work.
Thermo catalytic decomposition of methane over Pd/AC and Pd/CB catalysts for ...IJERA Editor
Hydrogen production studies have been carried using Thermo Catalytic Decomposition (TCD) Unit. Thermo catalytic decomposition of methane is an attractive route for COx free production of hydrogen required in fuel cells. Although metal based catalysts produce hydrogen at low temperatures, carbon formed during methane decomposition reaction rapidly deactivates the catalyst. The present work compares the results of 10 wt% Pd supported on commercially available activated carbon and carbon black catalysts (samples coded as Pd10/AC and Pd10/CB respectively) for methane decomposition reaction. Hydrogen has been produced by thermo catalytic decomposition of methane at 1123K and Volume Hourly Space Velocity (VHSV) of 1.62 L/h g on the activity of both the catalysts has been studied. XRD of the above catalysts revealed, moderately crystalline peaks of Pd which may be responsible for the increase in catalytic life and formation of carbon fibers. Also during life studies (850°C and 54 sccm of methane) it has been observed that the activity of carbon black is sustainable for a longer time compared to that of activated carbon.
Simulation of N2 Gas Separation Process from AirIOSR Journals
Various components of air have been separated for different purposes for their easy availability in the atmosphere. Among those components Nitrogen separation process is very important in chemical engineering sector since it has wide usage in different processes. There are various technologies that are used for the separation of nitrogen. Among those most common is via LINDE-HAMPSON cycle. This paper presents analysis of thermodynamic cycle commonly used for liquefaction of Nitrogen (N2) under given set of operating condition and efficiencies. The liquefying temperature of Nitrogen being -200oC is taken into consideration. This paper also presents the simulation of this process HYSYS for the separation of N2 from air. Simulation result gives the value of product nitrogen purity of 91.75%
This document provides information on dissolved gas analysis (DGA), a technique used to detect faults in oil-filled transformers. It discusses how DGA works, standards and guidelines, gas extraction methods, common fault gases and their sources, analysis using gas chromatography, and approaches to interpreting DGA results including key gas ratios and levels that indicate different fault conditions. DGA allows early detection of transformer issues and monitoring of transformer health through analysis of the gases dissolved in transformer oil.
An Experimental Investigation on Application of Al2O3 Nanoparticles as Lubric...IJERA Editor
This document investigates the use of Al2O3 nanoparticles as an additive to compressor oil in vapor compression refrigeration systems (VCRS). Experimental tests were conducted adding Al2O3 nanoparticles to PAG oil at concentrations of 1.5%, 1.7%, and 1.9% by mass. Results showed that the coefficient of performance (COP) of the VCRS improved by 19.14%, 21.6%, and 11.22%, respectively, compared to using pure oil. The maximum COP and refrigeration effect occurred at a concentration of 1.7% Al2O3 nanoparticles. Theoretical COP and system capacity were also highest at this concentration. Therefore, adding Al2O3 nanoparticles to compressor oil,
Una soluzione efficiente e competitiva con un basso GWP - F. Flohr - DaikinCentro Studi Galileo
Convegno Europeo
IL PASSAGGIO AI REFRIGERANTI ALTERNATIVI:
IMPATTO SU IMPIANTI NUOVI ED ESISTENTI
Le Ultime Tecnologie nel Condizionamento e nella Refrigerazione; Sistemi, Attrezzatura, Componenti, Formazione e Certificazione; il Phase Down
15 marzo 2018 | 14.00 - 18.30
Mostra Convegno Expocomfort
Centro Congressi Stella Polare: Sala Sagittarius
Organizzato da ATF - Associazione Tecnici del Freddo
Changing Best Practices in Flue Gas AnalysisYokogawa1
Zirconium Oxide and Catalytic Bead sensor based analyzers have been the primary means of flue gas analysis for control and safety. The recently published API-556 has highlighted several considerations when using these technologies that were not commonly known throughout the industry. This webinar will explain the theory of operation of tunable diode laser spectrometers and the application thereof to gas fired reformers, boilers, & heaters as a layer of protection during startup and efficiency diagnostic during operation.
During this webinar recording, you will learn:
-What is the purpose of flue gas?
-The evolution of flue gas Analyzers
-Industry standards and recommended practices on the application of different types of instruments
SteriSense is a brand new and innovative device for
Electronic Bowie Dick Tests that is unmatched in
accuracy, performance and reliability. ISO 11140-4
Compliant
R32 refrigerant has a GWP of 675, about one-third that of R410A which has a GWP of 2088. The revised F-Gas regulation in Europe will significantly limit HFC refrigerants starting in 2020 based on their GWP and phase them down by 80% by 2030. R32 is a viable alternative to higher-GWP refrigerants as a single component refrigerant that allows for reduced charge sizes and system dimensions while maintaining efficiency. Some design aspects like compressor discharge temperatures can be managed with R32. Suitable oils are now available for use with R32.
The Claus process is the industry standard and so the most
significant gas desulfurizing process, recovering elemental sulfur
from gaseous hydrogen sulfide.
The process is commonly referred to as a sulfur recovery unit
(SRU) and is very widely used to produce sulfur from the
hydrogen sulfide found in raw natural gas and from the by-product
sour gases containing hydrogen sulfide derived from refining
petroleum crude oil and other industrial facilities.
There are many hundreds of Claus sulfur recovery units in
operation worldwide.
In fact, the vast majority of the 68,000,000 metric tons of sulfur
produced worldwide in one year is by-product sulfur from
petroleum refining and natural gas processing plants.
This document provides an overview of steam engineering principles from Spirax Sarco, a manufacturer of steam system products. It defines key steam terms and concepts, explains how steam is formed through the boiling of water, and discusses steam generation in boilers. It also covers steam piping design, metering of steam and condensate, control of steam through valves and traps, and condensate management. The goal is to educate on the fundamentals of steam systems and efficient steam usage.
Steam Reformer Surveys - Techniques for Optimization of Primary Reformer Oper...Gerard B. Hawkins
Introduction
Background Radiation and Temperature Measurement
Reformer Survey Inputs
Other Troubleshooting Tools
Safety
Preparation
Onsite Data Collection
TWT Survey
Observation/Troubleshooting
Modelling and Analysis
Results/Outputs
Case Studies
Conclusions
Case Study 1
Case Study 2
Case Study 3
Conclusions
STUDY OF PERFORMANCE EVALUATION OF DOMESTIC REFRIGERATOR WORKING WITH MIXTURE...IAEME Publication
In many developing countries Like India, most of the vapor compression based refrigeration, air conditioning and heat pump systems continue to run on halogenated refrigerants due to its excellent thermodynamic and thermo-physical properties apart from the low cost. However, the halogenated refrigerants have adverse environmental impacts such as ozone depletion potential (ODP) and global warming potential (GWP). This project is devoted to feasibility study of substitution of LPG which is locally available and comprises 24.4% propane, 56.4% butane and 17.2% isobutene. The LPG is cheap and possesses an environmentally friendly nature with no ozone depletion potential (ODP). It is used in Libya for cooking purposes .Experimental result showed that the LPG refrigerant with charge of 25g worked well under unloaded condition
IRJET- Life Cycle Testing of Hermetic Compressor using Hydro-Carbon RefrigerantIRJET Journal
This document summarizes a study that tested hermetic compressors using hydrocarbon refrigerants over a life cycle of 200 hours. The study selected R290 and R600a as alternative refrigerants to replace R134a and analyzed their properties. It constructed two conditioned rooms, one for maintaining a stable ambient temperature and the other for testing a window AC charged with refrigerant blends. The compressor was tested by running it for 200 hours and checking its parts. The results of compressor performance were then plotted. The methodology demonstrated how to select refrigerants, construct test rooms, install and charge an AC, test cooling parameters, and conclude on refrigerant mixtures.
Heat Recovery System to Save the Fuel (Bagasse) by Eliminating the Feedwater ...IRJET Journal
1) The document proposes a heat recovery system to save fuel (bagasse) in sugar plants by eliminating the feedwater tank.
2) By taking the exhaust condensate directly to the deaerator tank and installing high-head pumps and pipes, water temperature reaching the boiler is increased from 94°C to 106-107°C.
3) This modification saves 3.857 tons/hour of exhaust steam previously used to heat the feedwater and reduces the required bagasse fuel firing rate from 60 to 56.63 tons/hour, saving 3.37 tons/hour of bagasse fuel.
The GC 5000 series are online gas chromatographs developed for the continuous monitoring of organic compounds in ambient air. They feature rugged and compact designs and can detect organic pollutants in the low ppb to ppt range. Various configurations are available to monitor compounds like BTEX, ozone precursors, and other organic pollutants. They use sample pre-concentration and thermal desorption for introduction of volatile organic compounds. Flame ionization and photoionization detectors provide sensitive detection of organic pollutants.
The document describes the testo 360 portable reference flue gas analyzer.
[1] The testo 360 provides accurate measurements of flue gas parameters like O2, CO, NO, NO2, SO2, and CO2 that are compatible with stationary analyzers.
[2] It is designed to withstand harsh industrial conditions with high temperatures, dust, and long-term use for emission testing and combustion system maintenance.
[3] The system includes a rugged analyzer unit, notebook computer for operation and data storage, and a selection of industrial flue gas probes for different temperature ranges.
This document discusses process improvements in sulfur industries, specifically the Claus process used to convert hydrogen sulfide gas into elemental sulfur. It describes two main approaches to process improvement: process integration and process intensification. Examples of process intensification techniques discussed include using a superclaus catalyst, tail gas clean-up processes, and oxygen enrichment of sulfur recovery units. The benefits of these techniques include increased sulfur production capacity, reduced emissions, and lower operating costs compared to building new facilities.
R410A refrigerant requires careful consideration of installation location to ensure proper performance and avoid issues. The outdoor unit location should allow unblocked airflow and avoid heat sources. Indoor units require minimum clearances and should not be placed too high or in locations blocking airflow. Installation tools and procedures also differ from R22 systems and require special gauges and charge hoses to handle higher pressures.
The document provides details of a project to produce bioethanol from glycerol using Enterobacter aerogenes TISTR1468. It summarizes the production process, which involves micro-aerobic fermentation, stripping, binary distillation, extraction, and flash vaporization. Key production metrics are given, such as a production rate of 3676.47 kg of bioethanol per hour. It also lists several chapters that require improvement work, such as redesigning the bioreactors, correcting heat integration calculations, completing control loops and relief valves on piping and instrumentation diagrams, and redesigning process units based on new stream data.
This document discusses operating pre-reformers at high temperatures and the associated benefits and drawbacks. It notes that while higher temperatures allow for better thermal efficiency and feedstock flexibility in reformers, they can also cause hydrothermal sintering of catalysts over time from high heat and steam. The document provides guidelines for startup, reduction, and operation of pre-reformer catalysts to maximize performance while mitigating sintering risks.
1. Introduction reasons for purification, types of poisons, and typical systems
2. Hydrogenation
3. Dechlorination
4. Sulfur Removal
5. Purification system start-up and shut-down
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
Simulation of N2 Gas Separation Process from AirIOSR Journals
Various components of air have been separated for different purposes for their easy availability in the atmosphere. Among those components Nitrogen separation process is very important in chemical engineering sector since it has wide usage in different processes. There are various technologies that are used for the separation of nitrogen. Among those most common is via LINDE-HAMPSON cycle. This paper presents analysis of thermodynamic cycle commonly used for liquefaction of Nitrogen (N2) under given set of operating condition and efficiencies. The liquefying temperature of Nitrogen being -200oC is taken into consideration. This paper also presents the simulation of this process HYSYS for the separation of N2 from air. Simulation result gives the value of product nitrogen purity of 91.75%
This document provides information on dissolved gas analysis (DGA), a technique used to detect faults in oil-filled transformers. It discusses how DGA works, standards and guidelines, gas extraction methods, common fault gases and their sources, analysis using gas chromatography, and approaches to interpreting DGA results including key gas ratios and levels that indicate different fault conditions. DGA allows early detection of transformer issues and monitoring of transformer health through analysis of the gases dissolved in transformer oil.
An Experimental Investigation on Application of Al2O3 Nanoparticles as Lubric...IJERA Editor
This document investigates the use of Al2O3 nanoparticles as an additive to compressor oil in vapor compression refrigeration systems (VCRS). Experimental tests were conducted adding Al2O3 nanoparticles to PAG oil at concentrations of 1.5%, 1.7%, and 1.9% by mass. Results showed that the coefficient of performance (COP) of the VCRS improved by 19.14%, 21.6%, and 11.22%, respectively, compared to using pure oil. The maximum COP and refrigeration effect occurred at a concentration of 1.7% Al2O3 nanoparticles. Theoretical COP and system capacity were also highest at this concentration. Therefore, adding Al2O3 nanoparticles to compressor oil,
Una soluzione efficiente e competitiva con un basso GWP - F. Flohr - DaikinCentro Studi Galileo
Convegno Europeo
IL PASSAGGIO AI REFRIGERANTI ALTERNATIVI:
IMPATTO SU IMPIANTI NUOVI ED ESISTENTI
Le Ultime Tecnologie nel Condizionamento e nella Refrigerazione; Sistemi, Attrezzatura, Componenti, Formazione e Certificazione; il Phase Down
15 marzo 2018 | 14.00 - 18.30
Mostra Convegno Expocomfort
Centro Congressi Stella Polare: Sala Sagittarius
Organizzato da ATF - Associazione Tecnici del Freddo
Changing Best Practices in Flue Gas AnalysisYokogawa1
Zirconium Oxide and Catalytic Bead sensor based analyzers have been the primary means of flue gas analysis for control and safety. The recently published API-556 has highlighted several considerations when using these technologies that were not commonly known throughout the industry. This webinar will explain the theory of operation of tunable diode laser spectrometers and the application thereof to gas fired reformers, boilers, & heaters as a layer of protection during startup and efficiency diagnostic during operation.
During this webinar recording, you will learn:
-What is the purpose of flue gas?
-The evolution of flue gas Analyzers
-Industry standards and recommended practices on the application of different types of instruments
SteriSense is a brand new and innovative device for
Electronic Bowie Dick Tests that is unmatched in
accuracy, performance and reliability. ISO 11140-4
Compliant
R32 refrigerant has a GWP of 675, about one-third that of R410A which has a GWP of 2088. The revised F-Gas regulation in Europe will significantly limit HFC refrigerants starting in 2020 based on their GWP and phase them down by 80% by 2030. R32 is a viable alternative to higher-GWP refrigerants as a single component refrigerant that allows for reduced charge sizes and system dimensions while maintaining efficiency. Some design aspects like compressor discharge temperatures can be managed with R32. Suitable oils are now available for use with R32.
The Claus process is the industry standard and so the most
significant gas desulfurizing process, recovering elemental sulfur
from gaseous hydrogen sulfide.
The process is commonly referred to as a sulfur recovery unit
(SRU) and is very widely used to produce sulfur from the
hydrogen sulfide found in raw natural gas and from the by-product
sour gases containing hydrogen sulfide derived from refining
petroleum crude oil and other industrial facilities.
There are many hundreds of Claus sulfur recovery units in
operation worldwide.
In fact, the vast majority of the 68,000,000 metric tons of sulfur
produced worldwide in one year is by-product sulfur from
petroleum refining and natural gas processing plants.
This document provides an overview of steam engineering principles from Spirax Sarco, a manufacturer of steam system products. It defines key steam terms and concepts, explains how steam is formed through the boiling of water, and discusses steam generation in boilers. It also covers steam piping design, metering of steam and condensate, control of steam through valves and traps, and condensate management. The goal is to educate on the fundamentals of steam systems and efficient steam usage.
Steam Reformer Surveys - Techniques for Optimization of Primary Reformer Oper...Gerard B. Hawkins
Introduction
Background Radiation and Temperature Measurement
Reformer Survey Inputs
Other Troubleshooting Tools
Safety
Preparation
Onsite Data Collection
TWT Survey
Observation/Troubleshooting
Modelling and Analysis
Results/Outputs
Case Studies
Conclusions
Case Study 1
Case Study 2
Case Study 3
Conclusions
STUDY OF PERFORMANCE EVALUATION OF DOMESTIC REFRIGERATOR WORKING WITH MIXTURE...IAEME Publication
In many developing countries Like India, most of the vapor compression based refrigeration, air conditioning and heat pump systems continue to run on halogenated refrigerants due to its excellent thermodynamic and thermo-physical properties apart from the low cost. However, the halogenated refrigerants have adverse environmental impacts such as ozone depletion potential (ODP) and global warming potential (GWP). This project is devoted to feasibility study of substitution of LPG which is locally available and comprises 24.4% propane, 56.4% butane and 17.2% isobutene. The LPG is cheap and possesses an environmentally friendly nature with no ozone depletion potential (ODP). It is used in Libya for cooking purposes .Experimental result showed that the LPG refrigerant with charge of 25g worked well under unloaded condition
IRJET- Life Cycle Testing of Hermetic Compressor using Hydro-Carbon RefrigerantIRJET Journal
This document summarizes a study that tested hermetic compressors using hydrocarbon refrigerants over a life cycle of 200 hours. The study selected R290 and R600a as alternative refrigerants to replace R134a and analyzed their properties. It constructed two conditioned rooms, one for maintaining a stable ambient temperature and the other for testing a window AC charged with refrigerant blends. The compressor was tested by running it for 200 hours and checking its parts. The results of compressor performance were then plotted. The methodology demonstrated how to select refrigerants, construct test rooms, install and charge an AC, test cooling parameters, and conclude on refrigerant mixtures.
Heat Recovery System to Save the Fuel (Bagasse) by Eliminating the Feedwater ...IRJET Journal
1) The document proposes a heat recovery system to save fuel (bagasse) in sugar plants by eliminating the feedwater tank.
2) By taking the exhaust condensate directly to the deaerator tank and installing high-head pumps and pipes, water temperature reaching the boiler is increased from 94°C to 106-107°C.
3) This modification saves 3.857 tons/hour of exhaust steam previously used to heat the feedwater and reduces the required bagasse fuel firing rate from 60 to 56.63 tons/hour, saving 3.37 tons/hour of bagasse fuel.
The GC 5000 series are online gas chromatographs developed for the continuous monitoring of organic compounds in ambient air. They feature rugged and compact designs and can detect organic pollutants in the low ppb to ppt range. Various configurations are available to monitor compounds like BTEX, ozone precursors, and other organic pollutants. They use sample pre-concentration and thermal desorption for introduction of volatile organic compounds. Flame ionization and photoionization detectors provide sensitive detection of organic pollutants.
The document describes the testo 360 portable reference flue gas analyzer.
[1] The testo 360 provides accurate measurements of flue gas parameters like O2, CO, NO, NO2, SO2, and CO2 that are compatible with stationary analyzers.
[2] It is designed to withstand harsh industrial conditions with high temperatures, dust, and long-term use for emission testing and combustion system maintenance.
[3] The system includes a rugged analyzer unit, notebook computer for operation and data storage, and a selection of industrial flue gas probes for different temperature ranges.
This document discusses process improvements in sulfur industries, specifically the Claus process used to convert hydrogen sulfide gas into elemental sulfur. It describes two main approaches to process improvement: process integration and process intensification. Examples of process intensification techniques discussed include using a superclaus catalyst, tail gas clean-up processes, and oxygen enrichment of sulfur recovery units. The benefits of these techniques include increased sulfur production capacity, reduced emissions, and lower operating costs compared to building new facilities.
R410A refrigerant requires careful consideration of installation location to ensure proper performance and avoid issues. The outdoor unit location should allow unblocked airflow and avoid heat sources. Indoor units require minimum clearances and should not be placed too high or in locations blocking airflow. Installation tools and procedures also differ from R22 systems and require special gauges and charge hoses to handle higher pressures.
The document provides details of a project to produce bioethanol from glycerol using Enterobacter aerogenes TISTR1468. It summarizes the production process, which involves micro-aerobic fermentation, stripping, binary distillation, extraction, and flash vaporization. Key production metrics are given, such as a production rate of 3676.47 kg of bioethanol per hour. It also lists several chapters that require improvement work, such as redesigning the bioreactors, correcting heat integration calculations, completing control loops and relief valves on piping and instrumentation diagrams, and redesigning process units based on new stream data.
This document discusses operating pre-reformers at high temperatures and the associated benefits and drawbacks. It notes that while higher temperatures allow for better thermal efficiency and feedstock flexibility in reformers, they can also cause hydrothermal sintering of catalysts over time from high heat and steam. The document provides guidelines for startup, reduction, and operation of pre-reformer catalysts to maximize performance while mitigating sintering risks.
1. Introduction reasons for purification, types of poisons, and typical systems
2. Hydrogenation
3. Dechlorination
4. Sulfur Removal
5. Purification system start-up and shut-down
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
This document describes a remote intelligent automatic error detection system for power grids using SMS alerts sent via GSM. Sensors monitor the power grid for errors like faults, low battery, oil leaks, abnormal speeds, and temperatures. If an error is detected, the sensor sends an SMS via GSM to alert engineers. The system aims to automate error detection and notification to reduce costs and improve response times compared to manual methods.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
The document summarizes the design and manufacturing of a twin lobe roots blower using a steel shaft. It describes the limitations of the existing cast iron shaft design and motivates switching to a steel shaft. The steel shaft design is analyzed using FEA software to validate it can withstand the stresses. Key steps included determining shaft geometry, selecting bearings, and comparing performance to the original design. Testing showed the blower met requirements for noise, vibration, power, airflow, pressure, and temperature rise.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
This document summarizes a research paper that proposes a novel approach to designing a low power 6T (8x8) SRAM cell using MOS Current Mode Logic (MCML) technique at a 45nm technology node. Simulation results show that an SRAM cell array designed with MCML achieves significant reductions in power dissipation, leakage current, and static power compared to a conventional 6T SRAM cell design. At a supply voltage of 1.2V, the MCML design achieves a power dissipation of 128.6uW versus 480.3uW for the conventional design. The MCML design also exhibits lower leakage current, static power, power-delay product, and energy-delay product. Therefore
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
El documento describe diferentes tipos de defectos que pueden ocurrir en pieles de animales a lo largo de los procesos de curtición, como marcas de quemaduras, picaduras de insectos, cortes y moretones. Para cada defecto, indica posibles causas y formas de repararlo, como lijar, estucar, pigmentar u otros métodos, dependiendo de la gravedad del daño.
El amor verdadero requiere de compromiso, respeto y confianza mutua entre las personas más allá de los sentimientos pasajeros. Una relación sólida se basa en el apoyo emocional y el entendimiento entre la pareja a través de los buenos y malos momentos.
Telefonía móvil en áreas rurales: Oportunidades para la agriculturaRIBDA 2009
El documento describe cómo los teléfonos celulares pueden proporcionar acceso a las tecnologías de la información y la comunicación a las comunidades agrícolas y permitirles una plataforma eficaz para la Web 2.0. Se analizan varias iniciativas en América, Asia y África que usan mensajes de texto para brindar servicios a los agricultores. También se discute el programa de código abierto Frontlinesms y cómo las organizaciones de agricultores pueden usarlo para mejorar la comercialización de sus productos a través del
Inmaculada Garbajosa Barroso Y Tamara Garbajosa BarrosoInmaculadayTamara
Jack era el hermano más joven de una familia de piratas. A diferencia de sus hermanos mayores, que habían descubierto sus talentos como artesano y cazador de tesoros respectivamente, Jack no había descubierto aún el suyo. Su abuelo le contó sobre un tesoro escondido en una isla cercana e inaccesible, y lo animó a ir a buscarlo para descubrir su talento. Aunque con dudas, Jack emprendió el viaje. Al enfrentarse a tiburones, aves y cangrejos agresivos, log
La Privatización del Agua en el Web de la Ciencia (WoS) según la evidencia de...RIBDA 2009
Este documento presenta los resultados de un análisis bibliométrico y de contenido sobre la privatización del agua. Se analizaron 57 artículos indexados en el Web of Science para identificar los principales temas y redes de cocitación. Los resultados mostraron que los temas más frecuentes son la privatización del modelo británico, el suministro de agua y saneamiento en América Latina, y los costos económicos y sociales del suministro de saneamiento. Se recomienda replicar este método en otras bases de datos y analizar otros tem
This document discusses the thermodynamic analysis of a nitrogen liquefaction system based on the Kapitza cycle, which is a modified Claude cycle. Some key points:
- The Kapitza cycle was modified from the Claude cycle by eliminating the third heat exchanger and using a rotary expander instead of a reciprocating one.
- A mathematical model of the Kapitza cycle was developed using EES to evaluate parameters like expander flow fraction, isentropic efficiency, and the figure of merit (FOM) of the cycle.
- The FOM is defined as the ratio of theoretical minimum work to actual work and provides a measure of how close the real system comes to ideal performance.
MODEL BASED ANALYSIS OF TEMPERATURE PROCESS UNDER VARIOUS CONTROL STRATEGIES ...Journal For Research
This paper analyze the temperature process in an empirical model. From the empirical model the system behavior is determined by transfer function and the basic controller strategies Ziegler-Nichols & Cohen-Coon method are implemented in it. With these tuning methods the best control strategies are obtained at the final stage by interfacing the system with NI-myRIO kit.
Tube Wall Temperature Measurement On Steam Reformers - Best PracticesGerard B. Hawkins
GBH Enterprises provides guidance on best practices for measuring tube wall temperatures in steam reformers using optical pyrometers. It is important to measure temperatures accurately to prevent overheating tubes while maximizing plant efficiency. GBH recommends taking multiple temperature and background readings per tube using handheld pyrometers and an emissivity correction factor. Safety precautions like protective equipment are also advised. Detailed procedures are outlined for top-fired, side-fired and terrace wall furnace configurations.
IRJET- Design and Analysis of Split Refrigeration System with Indoor & Ou...IRJET Journal
This document describes an experimental study that analyzed the performance of a refrigeration system with indoor and outdoor condenser units. Two cases were considered: case 1 with both units inside the room, and case 2 with one unit outside the room. The results found that case 2 had a 1.9% lower average room temperature and a 15.9% lower evaporator temperature compared to case 1. The minimum evaporator temperature was similar between the two cases. In conclusion, having one condenser unit outside the room improved the refrigeration system's performance by lowering temperatures. Future work could explore using alternative refrigerants and accounting for pressure losses.
The document discusses natural gas liquid (NGL) recovery processes. It describes several types of NGL recovery processes including refrigeration processes like mechanical refrigeration, self-refrigeration, and cryogenic refrigeration. It also discusses lean oil absorption, solid bed adsorption, membrane separation, and twister supersonic separation. The document provides details on different types of natural gas reservoirs and discusses various refrigeration techniques in depth. It concludes by mentioning modern NGL recovery processes are based on turbo expanders using reflux configurations.
Thermogravimetric analysis (TGA) involves measuring the weight of a substance as it is heated, and can be used to analyze mixtures, determine drying temperatures, and study reaction kinetics. TGA works by heating a sample in a furnace while precisely measuring its weight on a high-precision balance. Derivative thermogravimetric analysis (DTGA) measures the rate of weight change during heating. TGA can identify different components in a mixture based on their unique thermal decomposition profiles, and determine optimum drying ranges to isolate compounds like calcium oxalate. Kinetic parameters of reactions can also be extracted from TGA or DTGA curves using dynamic or isothermal methods.
1) The document analyzes the performance of a domestic refrigerator using nanofluids made of PAG oil and different mass fractions of Al2O3 nanoparticles, with R134a as the refrigerant.
2) Experiments show that using nanofluids reduces energy consumption by up to 26.6% and increases the freezing capacity of the refrigerator, compared to using PAG oil alone.
3) The coefficient of performance (COP) of the refrigerator is improved by up to 39.46% when using a 1.42% mass fraction of Al2O3 nanoparticles in the PAG oil. Higher nanoparticle concentrations lead to better thermal conductivity and heat transfer, enhancing refrigerator performance.
Psychrometry
0 INTRODUCTION / PURPOSE
1 SCOPE
2 FIELD OF APPLICATION
3 DEFINITIONS
4 PSYCHROMETRIC CHARTS
5 EXAMPLE CALCULATION
6 CHARTS FOR SPECIFIC SYSTEMS
7 BIBLIOGRAPHY
FIGURES
1 GROSVENOR CHART (Humidity vs. Temperature)
FOR AIR-WATER VAPOR AT 1.0133 bar
2 MOLLIER CHART (Enthalpy vs. Humidity) FOR
NITROGEN-TOLUENE VAPOR AT 100 kPa
1. A reversible process is an idealized process that can be reversed without leaving any trace on the system or surroundings.
2. Reversible processes do not occur in nature, but serve as theoretical limits that actual irreversible processes can approach.
3. The Carnot cycle, composed of reversible processes, achieves the maximum possible efficiency between two temperature reservoirs. No heat engine can have a higher efficiency than a Carnot engine operating between the same reservoirs.
Temperature Control for a Cryogenic Freezer for Bovine Semen Samples for Assi...IRJET Journal
This document describes a temperature control system for a cryogenic freezer used to freeze bovine semen samples. The system uses a PID controller in a pole placement scheme to track an internationally accepted freezing temperature profile. This is intended to increase sperm survival rates from the current 50% achieved with traditional freezing methods. The control system is designed around inexpensive, discrete components to provide an affordable alternative for cryogenic control applications like freezing bovine semen. Simulation results indicate the controller can successfully track the freezing profile and may increase sperm survival if certain efficiency improvements are made to the cryogenic freezer prototype.
1. The study compared the power consumption of air cooling versus water cooling for an extrusion process using four different resins.
2. Water cooling used slightly more energy than air cooling for all resins, with the greatest difference seen in PET where water cooling used 80% more energy.
3. Air cooling is recommended for dedicated processes as it provides sufficient cooling with less energy use than water cooling, however the screw design must match the resin to avoid excessive heating or cooling needs.
Temperature excursions in hydrogenation reactors may have several causes, the most common ones being:-
i) Loss of recycle quench system. This could be either the liquid or gas stream. The condition is made worse if the make-up gas keeps flowing.
ii) Excessive temperatures. The loss of cooling medium ........
New ag associates heatpulse 210 rapid thermal annealing systemPeter Chen
Allwin21 Corp is the exclusive manufacturer of AG Associates Heatpulse 610 rapid thermal processing (RTP) equipment. RTP uses high intensity lamps to heat silicon wafers to temperatures up to 1250°C in seconds for processes like dopant activation, thermal oxidation, and chemical vapor deposition. Allwin21's AccuThermo AW RTP systems provide improved temperature control, repeatability, uniformity, and stability compared to traditional RTP systems due to advanced software and temperature control technologies developed over decades of research. RTP is used for short semiconductor manufacturing processes requiring fast heating and cooling, in contrast to longer batch furnace processes.
New ag associates heatpulse 410 rapid thermal annealing systemPeter Chen
Allwin21 Corp is the exclusive manufacturer of AG Associates Heatpulse 610 rapid thermal processing (RTP) equipment. RTP uses high intensity lamps to heat silicon wafers to temperatures up to 1250°C in seconds for processes like dopant activation, thermal oxidation, and chemical vapor deposition. Compared to traditional batch furnaces, RTP provides faster heating and cooling rates, precise temperature control, and shorter process times. Allwin21's AccuThermo AW RTP systems offer advanced temperature control technologies for improved repeatability, uniformity, and stability in rapid thermal processing.
New ag associates heatpulse 610 rapid thermal annealing systemPeter Chen
Allwin21 Corp is the exclusive manufacturer of AG Associates Heatpulse 610 rapid thermal processing (RTP) systems. The AccuThermo AW610 RTP uses high intensity lamps to heat single wafers for short periods of 1-600 seconds at precisely controlled temperatures for applications like dopant activation, thermal oxidation, and silicide formation. Key features include advanced temperature control software, consistent wafer-to-wafer repeatability, and small footprint. RTP provides advantages over conventional furnaces for semiconductor manufacturing processes requiring short, high temperature cycles.
AccuThermo AW 610 Rapid Thermal Annealing EquipmentPeter Chen
The AccuThermo AW610 was derived from the AG Associates 610 production-proven design. Allwin21 Corp. is the exclusive manufacturer of the AG Associates Heatpulse 610 desktop atmospheric RTP (Rapid Thermal Processing) system. The system uses high intensity visible radiation to heat single wafer for short process periods of time at precisely controlled temperatures. The process periods are typically 1 600 seconds in duration, although periods of up to 9999 seconds can be selected. These capabilities, combined with the heating chamber's cold-wall design and superior heating uniformity, provide significant advantages over conventional furnace processing.
Study & Review of Heat Recovery Systems for SO2 Gas Generation Process in Sug...IRJET Journal
This document summarizes a study on heat recovery systems for the SO2 gas generation process in the sugar industry. It begins with an introduction to waste heat recovery and its importance. It then reviews various methods for recovering waste heat. The document discusses factors that affect waste heat recovery systems like heat quantity and quality. It reviews several past studies on waste heat recovery in different industries. It proposes studying heat recovery from the SO2 gas generation process in sugar production to make the process more efficient. The conclusion emphasizes the need for waste heat recovery techniques in industries to conserve energy.
IRJET- Enhancement of COP of Vapor Compression Refrigeration Cycle using CFDIRJET Journal
This document discusses enhancing the coefficient of performance (COP) of a vapor compression refrigeration cycle using computational fluid dynamics (CFD).
It presents a study that uses a diffuser between the compressor and condenser to reduce the kinetic energy of the refrigerant leaving the compressor. This lowers the power input to the compressor, thereby improving the COP. Experimental results found adding a 15 degree divergence angle diffuser increased the COP from 3.83 to 5.55, a 31% enhancement.
The experimental results are validated using CFD modeling and analysis software. Modeling and meshing is done in ICEMCFD, analysis in CFX, and post-processing in CFD POST to verify the COP improvement
This document provides an introduction to process instrumentation and discusses different types of filled system thermometers. It describes the construction, operating principle, and classification of filled system thermometers. The four main classes described are liquid filled, vapour filled, gas filled, and mercury filled thermometers. The document also discusses sources of error in filled system thermometers and compares their advantages and disadvantages to other temperature measurement instruments.
High Temperature Shift Catalyst Reduction ProcedureGerard B. Hawkins
High Temperature Shift Catalyst Reduction Procedure
The catalyst, as supplied, is Fe2O3. This reduces to the active form, Fe3O4, in the presence of hydrogen when process gas is admitted to the reactor.
1. The mildly exothermic reactions are:
3 Fe2O3 + H2 ========= 2 Fe3O4 + H2O
3 Fe2O3 + CO ========= 2 Fe3O4 + CO2
High Temperature Shift Catalyst Reduction Procedure
Mq2420912096
1. Mazidah Tajjudin, Mohd Hezri Fazalul Rahiman, Norlela Ishak, Hashimah Ismail, Norhashim
Mohd Arshad, Ramli Adnan / International Journal of Engineering Research and Applications
(IJERA) ISSN: 2248-9622 www.ijera.com Vol. 2, Issue4, July-august 2012, pp.2091-2096
Modified Relay Tuning PI with Error Switching: A Case Study
on Steam Temperature Regulation
Mazidah Tajjudin*, Mohd Hezri Fazalul Rahiman*, Norlela Ishak*,
Hashimah Ismail#, Norhashim Mohd Arshad*, Ramli Adnan*.
*Faculty of Electrical Engineering University teknologi MARA, Shah Alam, Malaysia.
#
Faculty of Engineering, University Selangor, Malaysia.
Abstract
This study evaluates the performance The closed-loop system becomes critically stable
between reaction curve Ziegler-Nichols tuning whereby the ultimate period and gain are acquired.
rules applied to FOPDT model and the open-loop This method is not easy to apply on a working plant
relay feedback tuning method based on ultimate because the system might be brought to unstable state.
gain and period. Error and control signal Anyway, these methods were very limited that led to
switching were equipped to enhance the output an endless discussions and studies being conducted in
response over a limited steam temperature order to improve it.
response. The control performance was evaluated Alternatively, Astrom and Huggland
experimentally on a steam distillation process proposed a more practical solution using a relay
regulation. The proposed technique employing feedback test [9] where the automatic tuning was
relay tuning together with error switching had performed online by switching from automatic mode
produced an astounding closed-loop response even to tuning mode. Details on the implementation can be
for a non-linear steam temperature control. referred in [9–12].
Keywords – steam temperature; PI control; This paper shared the idea of relay
Ziegler-Nichols tuning; relay feedback. perturbation on the process in order to get the process
gain and frequency. But, instead of implementing a
1. INTRODUCTION closed-loop auto-tuned, this method gathered the
PID controller has been successfully applied information from the open-loop response. From these
in industries. However, optimal performance of the two parameters, the PID was then tuned using the
controller is really depends on the tuning method. classical Ziegler-Nichols rules. This simple approach
Some prominent tuning methods are the Ziegler- unbelievably produced better results than a model-
Nichols, pole-placement and frequency domain based tuning approach as discussed in [13] for metal
specifications. The main issue in PID tuning is that, chamber temperature control. However, in this
there was no general tuning method applicable for all application, the temperature response was quite linear
types of applications. and the dynamic response was fast. Regulating a
Aidan[1], [2] had summarized more than steam temperature was more challenging.
twenty methods of PID tuning with their suitable Steam temperature control had been
applications and process types. Cominos and Munro performed using various control techniques. Most
[3] discussed on the most favorable PID tuning literatures focused on the superheated steam
techniques with their suitable application. More temperature control but some had done a study on
studies being done to improvised or synthesized a new saturated steam temperature [12]. Nevertheless,
rule [4] to a specific process type such as an regardless of its temperature range, the studies had
integrating process [5], integral plus time-delay pointed out the same non-trivial issues in steam
process [6], and first-order plus dead-time [7]. temperature regulation which is normally comes from
Moreover, the fitness of Ziegler-Nichols rules are also the nonlinearity, slow varying process dynamics, fast
depends on the relative time-delay of the process, see disturbance and unmodeled dynamics [14–17]. These
[8]. characteristics made model-based tuning ineffective
Generally, Ziegler-Nichols tuning method for steam temperature regulation.
was synthesized based on the step response and This study supported the statement by
frequency response methods. The first approach comparing the output gathered from the proposed
requires some information from the open-loop step tuning method and compared it against the model-
response which is the gain, time lag and dead-time. based Ziegler-Nichols PID. Experimental results will
The latter is based on the closed-loop response under demonstrate this issue evidently.
proportional control. Here, the gain is increased until
2. PROCESS DESCRIPTION AND MODELING
Steam distillation is among the most popular
method for essential oil extraction process. The
proportion of different essential oils extracted by
2091 | P a g e
2. Mazidah Tajjudin, Mohd Hezri Fazalul Rahiman, Norlela Ishak, Hashimah Ismail, Norhashim
Mohd Arshad, Ramli Adnan / International Journal of Engineering Research and Applications
(IJERA) ISSN: 2248-9622 www.ijera.com Vol. 2, Issue4, July-august 2012, pp.2091-2096
steam distillation is 93% and the remaining 7% is
extracted by other methods such as hydro distillation
[18]. This method applies hot steam to extract the
essential oil from the raw materials. The mixture of
oil and steam will be condensed and separated at their
liquid form. In the majority of cases the oil is less
dense than the water and so forms the top layer of the
distillate and can be separated easily using proper
method and instruments.
A pilot-scale steam distillation plant
developed for this study consists of a stainless steel
column of 26 cm inner diameter and a vertically
mounted steel condenser to convert the steam into
liquid form. Figure 1 shows the simplified schematic
diagram of the plant. Two RTDs were installed; Fig.1 Schematic of a steam distillation process
RTD1 was immersed in the water to monitor water A)
temperature while RTD2 was installed 40cm from B) FOPDT from open-loop response
RTD1 to monitor the steam temperature inside the In process industry, first-order plus dead-
column. The distance of the sensor from its heat time (FOPDT) is the most common model structure
source will caused transport delay in steam that was used to represent a process [7], [25], [26]
temperature measurement. because the parameters are easier to identify and
During operation, steam will be generated by understandable. Most PID control tuning techniques
boiling the water inside the distillation column. In were derived based on FOPDT model acquired from
normal operation, the water volume is 10 liters. The the open-loop step test. From the response in figure 2,
water was heated up by a 1.5kW coil-type heater. It it can be observed that the steam temperature is not a
took about 3500s to boil the water. The open-loop linear variable over its full-range and obviously
response under normal operating condition is shown cannot be represented by the FOPDT model
in Figure 2. Column temperature that represents the accurately. However, the response are linear within
steam temperature started to rise gradually after 1500s specific range i.e. between [30 50]oC, [50 70]oC and
when water temperature is around 70oC. The steam [70 100]oC.
temperature increased exponentially until 80oC where This study was concerned to regulate the
the steam rate hiked to 100oC and saturates. steam temperature at 85oC where the essential oil
During closed-loop operation, the steam extraction took place. So, the operating range was
temperature will be measured by RTD2. RTD2 was limited to 80oC to 100oC only.
installed over the raw material to monitor the
temperature of steam that passed through the raw
Open-loop test
material instead of measuring the steam temperature
100
that will enter the raw material bed. Continual
exposure to excessive heat may degrade the quality of 90
Steam
Water
the essential oil as had been studied and reported in 80
Temperature,degC
[19] for ginger extraction. This finding was supported 70
by lots of literatures [20–24] from the area of
60
botanical and chemical studies.
Signal conversion was necessary to convert 50
the output from RTD (resistance) to voltage signal 40
that was compatible with the acquisition card PCI 30
1711. The signal converter converts 0oC to 120oC to 0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000
1V to 5V. 1 volt offset was intentionally put to avoid Time,s
misleading during measurement error. Control signal
Fig.2 Open-loop response of steam and water
from the controller manipulated the heater power by
temperature
providing a dc voltage from 0V to 5V to a continuous General form of the FOPDT model is as follows:
power controller.
Y(s) K p e −θs
= (1)
X(s) τs + 1
where
X(s) is the input
Y(s) is the output of the process
Kp is the process gain
τ is the time constant
2092 | P a g e
3. Mazidah Tajjudin, Mohd Hezri Fazalul Rahiman, Norlela Ishak, Hashimah Ismail, Norhashim
Mohd Arshad, Ramli Adnan / International Journal of Engineering Research and Applications
(IJERA) ISSN: 2248-9622 www.ijera.com Vol. 2, Issue4, July-august 2012, pp.2091-2096
θ is the dead-time 3. PID CONTROLLER TUNING
This section explained on the PID tuning
There were two methods available when methods applied during this study. Table 1
estimating FOPDT model from the process reaction summarizes the Ziegler-Nichols tuning rules based on
curve [27]. The first method required an inflection process reaction curve parameter that is Kp = 4.5, τ =
point to be determined to acquire an accurate model 160 and θ = 350. These rules make use of the parallel
whereas the second method requires data at specific structure PID where Kc is the controller gain, Ti is the
points which is much easier to be acquired. Using the integral time constant, and Td is the derivative time
second method of the process reaction curve will lead constant. The equation for parallel form PID is given
to the following equations: in equation 5. The calculated parameter was tabulated
Y θ + τ = ∆Y 1 − e−1 = 0.632 ∗ ∆Y in Table 3.
τ −1 (2)
Y θ+ = ∆Y 1 − e 3 = 0.283 ∗ ∆Y
3 1
𝐺𝑐 𝑠 = 𝐾𝑐 1 + + 𝑇𝑑 𝑠 (5)
𝑇𝑖 𝑠
Thus, the values of time at which the output TABLE 1 ZIEGLER-NICHOLS FROM FOPDT [27]
reaches 28.3% and 63.2% of its final value are used to Kc Ti Td
calculate the model parameters according to equation P 1 𝜏 - -
3.
τ 𝐾𝑝 𝜃
t 28% = θ +
3 PI 0.9 𝜏 3.3𝜃 -
𝐾𝑝 𝜃
t 63% = θ + τ
(3) PID 1.2 𝜏 2.0𝜃 0.5𝜃
τ = 1.5(t 63% − t 28% ) 𝐾𝑝 𝜃
θ = t 63% − τ The Ziegler-Nichols tuning PID from
This study applied the second method reaction curve method was compared with an open-
because it minimizes any doubt during inflection loop relay tuning. The proposed method was based on
determination and hence gave more consistent result. an open-loop on-off switching around the operating
The FOPDT model was given in equation 4. Model point. In this study, temperature set point was at 85oC.
validation was done by comparing the output of the To minimize the effect of measurement error,
model and experiment when subjected to 5 volt input hysteresis band of ±5oC was introduced. Manual on-
signal. The comparison produced RMSE = 0.3838oC. off switch was equipped in the system to turn the
Figure 4a shows the output from the model and controller into fully on or off when steam temperature
experiment while figure 4b shows the error between approaches 80oC and 90oC. Steam temperature was
both models. then oscillated between 80oC to 90oC. From the relay
output, PID gain was calculated using Ziegler-Nichols
4.5 rules based on frequency response analysis of the
G s = e−350 s , 80 ≤ 𝑇 ≤ 100℃ (4)
160s + 1 ultimate period and gain.
The process was started without a controller
FOPDT model validation
and the heater was controlled by a relay switch. The
100 relay was turned ON whenever steam temperature
95
reached 80oC and turned OFF when steam
Steam temperature,degC
90
temperature was at 90oC. The relay operation was
85
summarized by the following equation:
80
75
5 , 𝑇 ≤ 80℃
𝑢 𝑡 =
0 500 1000 1500
Time,sec
0 , 𝑇 ≥ 90℃ (6)
Fig. 4a Experimental output and model output
This process was repeated until a sustained
validation oscillation was observed as in figure 5. Figure 5a
Model error
shows the steam temperature response while figure 5b
2.5
2
1.5
1
shows the relay switching. The critical gain, Ku and
Model error,degC
0.5
0
critical period, Pu could be found from these output
-0.5
-1
and input signal. Ku was calculated using the
-1.5 following equation:
-2
-2.5
0 500 1000 1500
Time,sec
Fig. 4b Error between experimental and model (7)
output where
d = magnitude of relay (input)
a = magnitude of steam temperature (output)
2093 | P a g e
4. Mazidah Tajjudin, Mohd Hezri Fazalul Rahiman, Norlela Ishak, Hashimah Ismail, Norhashim
Mohd Arshad, Ramli Adnan / International Journal of Engineering Research and Applications
(IJERA) ISSN: 2248-9622 www.ijera.com Vol. 2, Issue4, July-august 2012, pp.2091-2096
information about Pu and Ku that was obtained from
Relay feedback output the open-loop relay switching. The method was
96
easier to implement rather than the model-based
94
Ziegler-Nichols tuning which requires a perfect
92
model in order to perform well. This study compared
90
Steam temperature,degC
the closed-loop response between these two methods.
88
The PI controller was developed using
86
MATLAB/Simulink software. Since the PI was tuned
84 between 80oC and 90oC, a control switch was set
82 prior to the controller block to enable the PI control
80 only after the steam temperature was greater than
78 80oC. Another switch was set before the controller to
76
0 500 1000 1500 2000 2500 3000 3500 4000 4500 5000
reset the error value when temperature was 80oC. By
Time,sec applying both switching, the controller gain will
performed accordingly as it was tuned. The switching
Fig. 5a Output from manual relay operation sequences were presented in equation 8 and 9 both
for the error and control switching respectively.
Relay input
0 , 𝑇 < 80℃ (8)
5
𝑒 𝑡 =
𝑒(𝑡) , 𝑇 ≥ 80℃
4
Control output, volt
5 , 𝑇 < 80℃
3
𝑢 𝑡 = (9)
𝑢(𝑡) , 𝑇 ≥ 80℃
2
1
Figure 6a shows the output response with PI
controller tuned using reaction curve method. The
0
resulting controller gain was smaller compared to the
0 500 1000 1500 2000 2500
Time,sec
3000 3500 4000 4500 5000 relay method and thus, producing a slower response.
The ability of PI controller in regulating desired set
point was evaluated with the presence of external
Fig. 5b Relay switching input signal disturbance. Steam temperature was disturbed by
adding 1 liter of water inside the tank when t =
From the values of Pu and Ku, PID 3500s.
controller can be calculated using Ziegler-Nichols Water temperature will drop which
rules in table 2. eventually reduced the steam temperature. From
figure 6a, steam temperature was dropped to 78oC
TABLE 2 ZIEGLER-NICHOLS FROM FREQUENCY 500 s after the water temperature. The controller
DOMAIN[27] reacts by producing a higher control signal that
Kc Ti Td increased the temperature to its desired value.
P 0.5𝐾 𝑢 Despite of the presence of integral form, the closed-
PI 𝐾𝑢 𝑃𝑢 loop response produced some offset during steady-
2.2 1.2 state but the steam temperature might settled down at
PID 𝐾𝑢 𝑃𝑢 𝑃𝑢 the desired set point beyond 7000s as can be
1.7 2 8 observed from the output.
PI with reaction curve tuning
This study implement a PI controller as the
100
process can be estimated with a first-order system.
90
The calculated PI parameters from both methods
80
were tabulated in Table 3.
Temperature,degC
70
60 Reference
TABLE 3 TUNED PID PARAMETERS Steam
50 Water
Tuning Kc Ti
40
method Disturbance
30
Reaction curve 0.09 1155
20
Relay feedback 0.9 900 0 1000 2000 3000
Time sec
4000 5000 6000 7000
4. EXPERIMENTAL RESULTS Fig. 6a Steam temperature with reaction curve
This section analyzed the output response tuning PI
regulated using PI controller but with different tuning
method. The proposed method was using the
2094 | P a g e
5. Mazidah Tajjudin, Mohd Hezri Fazalul Rahiman, Norlela Ishak, Hashimah Ismail, Norhashim
Mohd Arshad, Ramli Adnan / International Journal of Engineering Research and Applications
(IJERA) ISSN: 2248-9622 www.ijera.com Vol. 2, Issue4, July-august 2012, pp.2091-2096
5 P and I action (frequency tuning)
6
4.5 P action
I action
5
4 Switched Error
Control signal, volt
3.5 4
3
3
2.5
2 2
1.5
1
1
0
0.5
0 -1
0 1000 2000 3000 4000 5000 6000 7000
Time,sec
-2
-3
Fig. 6b PI control signal with reaction curve tuning 0 1000 2000 3000
Time,sec
4000 5000 6000 7000
The same procedure was repeated for the PI Fig. 7c P and I control signal with error switching
controller tuned with the relay input. The output and
control signal was given in figure 7a and 7b 5. CONCLUSION
respectively. Generally, the relay tuning PI produced Modified tuning based on relay input and
a faster and more accurate response. The output practical implementation of PI controller with error
oscillated around the set point within ±2% marginal. switching had been proposed and evaluated
experimentally on a non-linear steam temperature
PI with frequency tuning
regulation. The method was easy to implement but
100
the performance was outstanding when compared
90
with the classical PI with reaction curve tuning.
80
Temperature,degC
70
Reference REFERENCES
60
Steam
Water [1] A. O Dwyer, ―A summary of PI and PID
50 controller tuning rules for processes with
40 time delay . Part 1 : PI controller tuning
30 Disturbance
rules,‖ in IFAC Workshop on Digital
20
Control, 2000, pp. 175-180.
A. O Dwyer, ―PI and PID controller tuning
0 1000 2000 3000 4000 5000 6000 7000
Time,s [2]
rules for time delay processes : a summary .
Fig. 7a Steam temperature with frequency tuning PI Part 2 : PID controller tuning rules,‖ in
Proceedings of the Irish Signals and Systems
The control signal was relatively better Conference, pp. 339-346.
where it was smoother with no excessive turning on [3] P. Cominos and N. Munro, ―PID
and off compared with the reaction curve tuning. controllers:recent tuning methods and design
Figure 7c shows the individual control action of P to specification,‖ in IEE Proceeding in
and I together with error signal when switching was Control Theory and Applications, 2002.
activated. The advantage of error switching was that [4] Q.-guo Wang, T.-heng Lee, H.-wang Fung,
the error magnitude can be limited within 5oC only. Q. Bi, and Y. Zhang, ―PID tuning for
This could minimize the integral wind-up that will improved performance,‖ IEEE Transactions
increase the control signal until the error returned to on Control Systems Technology, vol. 7, no.
negative magnitude. As a result, a smoother control 4, pp. 457-465, Jul. 1999.
signal was attained as shown in figure 7b. [5] B. Rice and D. Cooper, ―Design and Tuning
of PID Controllers for Integrating ( Non-Self
5
Switched PI: frequency tuning
Regulating ) Processes,‖ Time, 2002.
4.5 [6] W. Hu, G. Xiao, and X. Li, ―An analytical
4 method for PID controller tuning with
3.5
specified gain and phase margins for integral
Control signal, volt
3
2.5
plus time delay processes.,‖ ISA
2 transactions, vol. 50, no. 2, pp. 268-76, Apr.
1.5
1
2011.
0.5
[7] S. Tavakoli and T. Mahdi, ―Optimal Tuning
0 Of PID Controllers for First Order plus
0 1000 2000 3000 4000 5000 6000 7000
Time,sec Time Delay Models Using Dimensional
Analysis,‖ in The Fourth International
Fig. 7b PI control signal with frequency tuning Conference on Control and Automation
(ICCA), 2003, vol. 1, no. June, pp. 942-946.
2095 | P a g e
6. Mazidah Tajjudin, Mohd Hezri Fazalul Rahiman, Norlela Ishak, Hashimah Ismail, Norhashim
Mohd Arshad, Ramli Adnan / International Journal of Engineering Research and Applications
(IJERA) ISSN: 2248-9622 www.ijera.com Vol. 2, Issue4, July-august 2012, pp.2091-2096
[8] K. Astrom and T. Hagglund, ―Revisiting the of Temperature on Extraction Rate,‖ Journal
Ziegler-Nichols step response method for of American Oil Chemists Society, no. 11,
PID control,‖ Journal of Process Control, pp. 1-4, 1951.
vol. 14, no. 6, pp. 635-650, Sep. 2004. [22] N. C. Nikolic, S. M. Cakic, S. M. Novakovi,
[9] A. Leva, ―PID autotuning algorithm based M. D. Cvetkovic, and M. Z. Stankovic,
on relay feedback,‖ IEE proceedings-D, vol. ―Effect of Extraction Techniques on Yield
140, no. 5, pp. 328-338, 1993. and Composition of Soybean Oil,‖
[10] K. J. Astrom, T. H. Lee, K. K. Tan, and K. Macedonian Journal of Chemistry and
H. Johansson, ―Recent Advances in Relay Chemical Engineering, vol. 28, no. 2, pp.
Feedback Methods-A SUrvey,‖ 1995, pp. 173-179, 2009.
2616-2621. [23] H. Fadel, F. Marx, A. El-Sawy, and A. El-
[11] C. C. Hang, K. J. Astrom, and Q. G. Wang, ghorab, ―Effect of extraction techniques on
―Relay feedback auto-tuning of process the chemical composition and antioxidant
controllers — a tutorial review,‖ Journal of activity of Eucalyptus camaldulensis var .
Process Control, vol. 12, pp. 143-162, 2002. brevirostris leaf oils,‖ Z Lebensm Unters
[12] K. J. Astrom and T. Hagglund, ―Practical Forsch A, vol. 208, pp. 212-216, 1999.
Experiences of Adaptive Techniques,‖ no. [24] Z. Burkus and F. Temelli, ―Effect of
1599, pp. 1599-1606. Extraction Conditions on Yield ,
[13] S.-jer Huang and Y.-ho Lo, ―Metal Chamber Composition , and Viscosity Stability of
Temperature control by Using Fuzzy PID Barley β-Glucan Gum,‖ vol. 75, no. 6, pp.
Gain Auto-tuning strategy,‖ WSEAS 805-809, 1998.
Transactions On Systems, vol. 4, no. 1, pp. [25] B. Yang, W.-zhou Li, and F. Yang, ―A new
1-10, 2009. PSO-PID tuning method for time-delay
[14] R. N. Silva, P. O. Shirley, J. M. Lemos, and processes,‖ 2008 2nd International
a. C. Gonçalves, ―Adaptive regulation of Symposium on Systems and Control in
super-heated steam temperature: a case Aerospace and Astronautics, pp. 1-6, Dec.
study in an industrial boiler,‖ Control 2008.
Engineering Practice, vol. 8, no. 12, pp. [26] J. Chen, ―System Identification and Control
1405-1415, Dec. 2000. of FOPDT or SOPDT Processes,‖ Journal of
[15] H. Liu, L. Nie, and H. Huang, ―Superheated Advanced Materials Research, vol. 317–
Steam Temperature Control Based on 319, pp. 2393-2397, Aug. 2011.
Active Disturbance Rejection Control & [27] T. E. Marlin, Process Control:Designing
Neural Network,‖ in Asia Pasific Power and Processes and Control Systems for Dynamic
Energy Engineering Conference, 2010, pp. Performance. 2000, pp. 179-181.
25-28.
[16] D. Zhao and P. Liang, ―Support Vector
Machine Predictive Control for Superheated
Steam Temperature Based on Particle
Swarm Optimization,‖ in Asia Pacific
Power and Energy Engineering Conference
(APPEEC), 2010, no. 05006518, pp. 1-4.
[17] G. L. Hou, J. H. Zhang, J. Wang, and Q. H.
Wu, ―Adaptive Sliding Mode and Fuzzy
Gain Scheduling Control for Steam
Temperature in Power Plants,‖ in UK
International Conference on Control, 2003.
[18] P. Masango, ―Cleaner production of
essential oils by steam distillation,‖ Journal
of Cleaner Production, vol. 13, pp. 833-839,
2005.
[19] N. A. Mohamed, ―Study on Important
Parameters Affecting the Hydrodistillation
for Ginger Oil Production,‖ 2005.
[20] E. Cassel, R. M. F. Vargas, N. Martinez, D.
Lorenzo, and E. Dellacassa, ―Steam
distillation modeling for essential oil
extraction process,‖ vol. 9, pp. 171-176,
2008.
[21] M. R. Wingard, R. C. Phillips, and B.-knox
Division, ―Solvent Extraction IV. The Effect
2096 | P a g e