Pub Date : 2001-04-29DOI: 10.1109/CITCON.2001.934099
T. J. Varty, N. Vera
The evolution in protective relays that started with simple discrete elements to replace electromechanical relays with static relays has resulted in the application of the modern multifunction, microprocessor based (/spl mu/PB) protective relays. The /spl mu/PB relays consist of elaborate schemes that include equipment protection, control, metering and communication to the plant control system. Further evolvement is envisaged. This paper reviews the present application of such relays in cement plants as related to high voltage and medium voltage equipment.
{"title":"Application of multi-function, micro-processor based protective relays in cement plants","authors":"T. J. Varty, N. Vera","doi":"10.1109/CITCON.2001.934099","DOIUrl":"https://doi.org/10.1109/CITCON.2001.934099","url":null,"abstract":"The evolution in protective relays that started with simple discrete elements to replace electromechanical relays with static relays has resulted in the application of the modern multifunction, microprocessor based (/spl mu/PB) protective relays. The /spl mu/PB relays consist of elaborate schemes that include equipment protection, control, metering and communication to the plant control system. Further evolvement is envisaged. This paper reviews the present application of such relays in cement plants as related to high voltage and medium voltage equipment.","PeriodicalId":412513,"journal":{"name":"IEEE-IAS/PCA 2001 Cement Industry Technical Conference. Conference Record (Cat. No.01CH37150)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128663717","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-04-29DOI: 10.1109/CITCON.2001.934106
M. Frailey, K. Happ
Capitol Cement's dry process line in San Antonio, Texas has recently been upgraded to a nominal clinker production of 1816 mtpd (2000 stpd). The production increase was accomplished by converting the existing in-line calciner to a separate-line down-draft calciner system, retrofitting all preheater stages to a low-pressure design, and making modifications to the existing vertical raw mill. Production and fuel consumption guarantees were met and the system operates with superior performance and reliability. This paper explores Capitol Cement's recent expansion project and identify the relevant system design and start-up issues. Capitol Cement has proved to be a pioneer in implementing emerging technologies, with the end result being that the upgraded dry line is presently one of the most modern kiln lines in the United States. Innovative features such as a down-draft calciner (DDC), a two-channel calciner burner, and a SO/sub 2/ reduction system (D-SO/sub x/) is presented. Interestingly, the SO/sub 2/ reduction system uses a portion of calciner exhaust gas to absorb volatile sulfur compounds from the upper-most preheater stages and thereby prevent their release into the atmosphere. This technology, and others, are presented in the context of the overall project execution.
{"title":"Capitol Cement's Project 2000","authors":"M. Frailey, K. Happ","doi":"10.1109/CITCON.2001.934106","DOIUrl":"https://doi.org/10.1109/CITCON.2001.934106","url":null,"abstract":"Capitol Cement's dry process line in San Antonio, Texas has recently been upgraded to a nominal clinker production of 1816 mtpd (2000 stpd). The production increase was accomplished by converting the existing in-line calciner to a separate-line down-draft calciner system, retrofitting all preheater stages to a low-pressure design, and making modifications to the existing vertical raw mill. Production and fuel consumption guarantees were met and the system operates with superior performance and reliability. This paper explores Capitol Cement's recent expansion project and identify the relevant system design and start-up issues. Capitol Cement has proved to be a pioneer in implementing emerging technologies, with the end result being that the upgraded dry line is presently one of the most modern kiln lines in the United States. Innovative features such as a down-draft calciner (DDC), a two-channel calciner burner, and a SO/sub 2/ reduction system (D-SO/sub x/) is presented. Interestingly, the SO/sub 2/ reduction system uses a portion of calciner exhaust gas to absorb volatile sulfur compounds from the upper-most preheater stages and thereby prevent their release into the atmosphere. This technology, and others, are presented in the context of the overall project execution.","PeriodicalId":412513,"journal":{"name":"IEEE-IAS/PCA 2001 Cement Industry Technical Conference. Conference Record (Cat. No.01CH37150)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127626369","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-04-29DOI: 10.1109/CITCON.2001.934096
C. Mcshane
Electrical distribution transformers insulation systems are being re-evaluated based on their total life cycle from economical, safety and environmental perspectives. Due to the inherently higher efficiency design offered by liquid cooled transformers, development has focused on fluids having improved environmental and health properties while maintaining the fire resistant properties of "less-flammable" fluids. This paper reports findings from several years of research and development on alternative dielectric systems using both natural and synthetic esters. Because esters have lower inherent resistance to oxidation than conventional mineral oil, a novel insulation system was developed to overcome this potential handicap. Single and three phase prototype field installations using these new dielectric coolants are discussed.
{"title":"Relative properties of the new combustion resistant vegetable oil based dielectric coolants","authors":"C. Mcshane","doi":"10.1109/CITCON.2001.934096","DOIUrl":"https://doi.org/10.1109/CITCON.2001.934096","url":null,"abstract":"Electrical distribution transformers insulation systems are being re-evaluated based on their total life cycle from economical, safety and environmental perspectives. Due to the inherently higher efficiency design offered by liquid cooled transformers, development has focused on fluids having improved environmental and health properties while maintaining the fire resistant properties of \"less-flammable\" fluids. This paper reports findings from several years of research and development on alternative dielectric systems using both natural and synthetic esters. Because esters have lower inherent resistance to oxidation than conventional mineral oil, a novel insulation system was developed to overcome this potential handicap. Single and three phase prototype field installations using these new dielectric coolants are discussed.","PeriodicalId":412513,"journal":{"name":"IEEE-IAS/PCA 2001 Cement Industry Technical Conference. Conference Record (Cat. No.01CH37150)","volume":"469 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133044594","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-04-29DOI: 10.1109/CITCON.2001.934125
P. Metcalfe
Web technologies and the Internet have revolutionized the computer industry. The Web browser technologies have also moved to portable devices such as personal digital assistants (PDAs) and mobile phones. This paper looks at how to implement a Web Server solution and addresses some of the inherent advantages in the technology. It also looks at some examples of how cement plant productivity can be managed with a web server approach.
{"title":"Managing plant productivity with a web server technology","authors":"P. Metcalfe","doi":"10.1109/CITCON.2001.934125","DOIUrl":"https://doi.org/10.1109/CITCON.2001.934125","url":null,"abstract":"Web technologies and the Internet have revolutionized the computer industry. The Web browser technologies have also moved to portable devices such as personal digital assistants (PDAs) and mobile phones. This paper looks at how to implement a Web Server solution and addresses some of the inherent advantages in the technology. It also looks at some examples of how cement plant productivity can be managed with a web server approach.","PeriodicalId":412513,"journal":{"name":"IEEE-IAS/PCA 2001 Cement Industry Technical Conference. Conference Record (Cat. No.01CH37150)","volume":"98 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133603577","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-04-29DOI: 10.1109/CITCON.2001.934102
D. Lake, J. Schaadt
In modern manufacturing, the kiln in the cement plant is among the most critical processes in terms of maintaining continuous plant output and quality. The kiln drive selection is, therefore, a critically important decision that must be made by considering not only the application characteristics but also the extreme need for system reliability. As technical alternatives for drive selection evolve, it is important to base decisions on the technology's "fit" to the application while understanding the risks and benefits these new choices offer. This paper profiles the application requirement and the available technologies. A selection criterion has been established that has been used to gauge the relative importance of the criteria and to assign a score for each attribute of each technology. A weighted sum score can be derived to analytically compare the available technologies versus the selection criteria. The analytical method will then be contrasted to more traditional selection methods to compare and correlate to the processes.
{"title":"Application and selection criteria evaluation of cement kiln drives","authors":"D. Lake, J. Schaadt","doi":"10.1109/CITCON.2001.934102","DOIUrl":"https://doi.org/10.1109/CITCON.2001.934102","url":null,"abstract":"In modern manufacturing, the kiln in the cement plant is among the most critical processes in terms of maintaining continuous plant output and quality. The kiln drive selection is, therefore, a critically important decision that must be made by considering not only the application characteristics but also the extreme need for system reliability. As technical alternatives for drive selection evolve, it is important to base decisions on the technology's \"fit\" to the application while understanding the risks and benefits these new choices offer. This paper profiles the application requirement and the available technologies. A selection criterion has been established that has been used to gauge the relative importance of the criteria and to assign a score for each attribute of each technology. A weighted sum score can be derived to analytically compare the available technologies versus the selection criteria. The analytical method will then be contrasted to more traditional selection methods to compare and correlate to the processes.","PeriodicalId":412513,"journal":{"name":"IEEE-IAS/PCA 2001 Cement Industry Technical Conference. Conference Record (Cat. No.01CH37150)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133460763","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-04-29DOI: 10.1109/CITCON.2001.934112
K. E. Williams
Every industry is a result of several key factors but most importantly it continues to thrive based on its ability to remain innovative. To remain innovative it must have: (I) a clear understanding of the forces that created it; (II) key primary factors that impact the process of the industry and contribute to the efficiency and cost competitiveness; (III) continual monitoring, documentation and proper perspective evaluation of operations as they pertain to the origins, recent past history and present day; and (IV) a willingness and team effort to test and advance not among it's peers, but ahead of them or at least in variations thereof to carry it to the future. The author reports on the 100% coke burning at Hercules. Although coke firing in the cement industry is not new this paper presents new concepts, brings together known facts and reveals new meaning by outlining similar discoveries to the past but most importantly present actual "different" operations as well as dispel past and present "myths".
{"title":"Hercules' experience in coke utilization for cement kiln firing (with discussions of related considerations)","authors":"K. E. Williams","doi":"10.1109/CITCON.2001.934112","DOIUrl":"https://doi.org/10.1109/CITCON.2001.934112","url":null,"abstract":"Every industry is a result of several key factors but most importantly it continues to thrive based on its ability to remain innovative. To remain innovative it must have: (I) a clear understanding of the forces that created it; (II) key primary factors that impact the process of the industry and contribute to the efficiency and cost competitiveness; (III) continual monitoring, documentation and proper perspective evaluation of operations as they pertain to the origins, recent past history and present day; and (IV) a willingness and team effort to test and advance not among it's peers, but ahead of them or at least in variations thereof to carry it to the future. The author reports on the 100% coke burning at Hercules. Although coke firing in the cement industry is not new this paper presents new concepts, brings together known facts and reveals new meaning by outlining similar discoveries to the past but most importantly present actual \"different\" operations as well as dispel past and present \"myths\".","PeriodicalId":412513,"journal":{"name":"IEEE-IAS/PCA 2001 Cement Industry Technical Conference. Conference Record (Cat. No.01CH37150)","volume":"82 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124076212","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-04-29DOI: 10.1109/CITCON.2001.934124
N. Biege, D. Smith, R. Shenk
The costs associated with corrosion of cement kiln baghouses can be as much as $100000 to $500000 per year for each kiln baghouse, depending upon the severity of the problem. Corrosion is caused by acid attack on carbon steel, resulting from the presence of acid producing compounds in raw material, fuels and additives. These compounds typically contain sulfur and chloride. However, weak acids such as carbonic acid can cause slow corrosion over a long period of time. The costs of baghouse corrosion include: repair of tube sheets and bag collars; repair of walls/hopper; cost of new, replacement dust collector; kiln downtime; bag replacement; environmental permit noncompliance fines; reduced production; personnel morale due to unpleasant task of bag replacement; safety hazards; and management distraction from making cement This paper explores the causes and costs of cement kiln baghouse corrosion. Typical system arrangements are discussed with a focus on identifying key problem areas for each unique system. Ways to identify the cause of the corrosion as well as strategies to reduce corrosion are elaborated on. Finally, four case studies are discussed to detail real world problems and solutions.
{"title":"Strategies for reducing cement kiln baghouse corrosion problems","authors":"N. Biege, D. Smith, R. Shenk","doi":"10.1109/CITCON.2001.934124","DOIUrl":"https://doi.org/10.1109/CITCON.2001.934124","url":null,"abstract":"The costs associated with corrosion of cement kiln baghouses can be as much as $100000 to $500000 per year for each kiln baghouse, depending upon the severity of the problem. Corrosion is caused by acid attack on carbon steel, resulting from the presence of acid producing compounds in raw material, fuels and additives. These compounds typically contain sulfur and chloride. However, weak acids such as carbonic acid can cause slow corrosion over a long period of time. The costs of baghouse corrosion include: repair of tube sheets and bag collars; repair of walls/hopper; cost of new, replacement dust collector; kiln downtime; bag replacement; environmental permit noncompliance fines; reduced production; personnel morale due to unpleasant task of bag replacement; safety hazards; and management distraction from making cement This paper explores the causes and costs of cement kiln baghouse corrosion. Typical system arrangements are discussed with a focus on identifying key problem areas for each unique system. Ways to identify the cause of the corrosion as well as strategies to reduce corrosion are elaborated on. Finally, four case studies are discussed to detail real world problems and solutions.","PeriodicalId":412513,"journal":{"name":"IEEE-IAS/PCA 2001 Cement Industry Technical Conference. Conference Record (Cat. No.01CH37150)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126138510","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-04-29DOI: 10.1109/CITCON.2001.934129
J. Claasen, N. Frewin, T. Lange
Cement manufacturing, like most other industries, is striving to become more optimal. This optimization implies the factory be controlled and managed as one integrated entity, where all operations and factors affecting production are managed in such a way so as to maximize production within business, quality and operational constraints. A key to achieving this objective is the use of advanced technology, specifically intelligent control systems (ICS) that allow for the embedding of process, business and other knowledge so that the interaction and consequences of all events and states on the plant can be understood and taken cognizance of. Such intelligent automation systems have been installed on a number of plants within the PPC group in South Africa. These systems provide an intelligent and unified view of the total plant where most operations are controlled and managed from the same console. This includes all basic and advanced process control process optimization, as well as logistics. Because such systems are continuously being upgraded and expanded, they are always relevant, up to date, and keep up with the changing needs of the cement company, always adding value.
{"title":"Integrated and intelligent plant wide control system for cement and lime plants","authors":"J. Claasen, N. Frewin, T. Lange","doi":"10.1109/CITCON.2001.934129","DOIUrl":"https://doi.org/10.1109/CITCON.2001.934129","url":null,"abstract":"Cement manufacturing, like most other industries, is striving to become more optimal. This optimization implies the factory be controlled and managed as one integrated entity, where all operations and factors affecting production are managed in such a way so as to maximize production within business, quality and operational constraints. A key to achieving this objective is the use of advanced technology, specifically intelligent control systems (ICS) that allow for the embedding of process, business and other knowledge so that the interaction and consequences of all events and states on the plant can be understood and taken cognizance of. Such intelligent automation systems have been installed on a number of plants within the PPC group in South Africa. These systems provide an intelligent and unified view of the total plant where most operations are controlled and managed from the same console. This includes all basic and advanced process control process optimization, as well as logistics. Because such systems are continuously being upgraded and expanded, they are always relevant, up to date, and keep up with the changing needs of the cement company, always adding value.","PeriodicalId":412513,"journal":{"name":"IEEE-IAS/PCA 2001 Cement Industry Technical Conference. Conference Record (Cat. No.01CH37150)","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127390365","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-04-29DOI: 10.1109/CITCON.2001.934121
S. J. Deery, A. Dougherty
The cement industry has made a strategic commitment to make safe practices an integral part of the manufacturing process and recognizes individual plants for innovative safety programs. The cement industry's Best Safe Practices Photographic Contest is sponsored by the Portland Cement Association (PCA), the American Portland Cement Alliance (APCA) and the Cement Association of Canada (CAC). This paper introduces the program and highlights the importance of safety to the North American cement industry. The paper outlines program requirements, judging criteria and entries submitted to date, and summarizes several entries. In addition, there is a discussion about PCA's planned Best Safe Practices Photographic Contest web page. This paper provides the cement industry with a current summary of the Best Safe Practices Photographic Contest. The Best Safe Practices program demonstrates how cement plants are committed to safety. This contest may, in the future, be used as a program model for other manufacturing industries.
{"title":"Best safe practices in cement plants","authors":"S. J. Deery, A. Dougherty","doi":"10.1109/CITCON.2001.934121","DOIUrl":"https://doi.org/10.1109/CITCON.2001.934121","url":null,"abstract":"The cement industry has made a strategic commitment to make safe practices an integral part of the manufacturing process and recognizes individual plants for innovative safety programs. The cement industry's Best Safe Practices Photographic Contest is sponsored by the Portland Cement Association (PCA), the American Portland Cement Alliance (APCA) and the Cement Association of Canada (CAC). This paper introduces the program and highlights the importance of safety to the North American cement industry. The paper outlines program requirements, judging criteria and entries submitted to date, and summarizes several entries. In addition, there is a discussion about PCA's planned Best Safe Practices Photographic Contest web page. This paper provides the cement industry with a current summary of the Best Safe Practices Photographic Contest. The Best Safe Practices program demonstrates how cement plants are committed to safety. This contest may, in the future, be used as a program model for other manufacturing industries.","PeriodicalId":412513,"journal":{"name":"IEEE-IAS/PCA 2001 Cement Industry Technical Conference. Conference Record (Cat. No.01CH37150)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123814821","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-04-29DOI: 10.1109/CITCON.2001.934119
B. Shafer
This is a review of the oxygen enrichment experience from the California Portland Cement Company, Mojave Plant. For approximately three years of operation, oxygen enrichment has been supplied by imported liquid oxygen, Recently, an onsite generation plant was commissioned and put into service. This paper will analyze injection strategy, refractory adjustments, production increases, and relative cost factors. Discussion will include the onsite generation which utilizes vacuum swing absorption technology. Finally, ongoing efforts to optimize combustion with oxygen injection in the calciner will be reviewed.
{"title":"Oxygen enrichment at California Portland Cement Company's Mojave Plant","authors":"B. Shafer","doi":"10.1109/CITCON.2001.934119","DOIUrl":"https://doi.org/10.1109/CITCON.2001.934119","url":null,"abstract":"This is a review of the oxygen enrichment experience from the California Portland Cement Company, Mojave Plant. For approximately three years of operation, oxygen enrichment has been supplied by imported liquid oxygen, Recently, an onsite generation plant was commissioned and put into service. This paper will analyze injection strategy, refractory adjustments, production increases, and relative cost factors. Discussion will include the onsite generation which utilizes vacuum swing absorption technology. Finally, ongoing efforts to optimize combustion with oxygen injection in the calciner will be reviewed.","PeriodicalId":412513,"journal":{"name":"IEEE-IAS/PCA 2001 Cement Industry Technical Conference. Conference Record (Cat. No.01CH37150)","volume":"144 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2001-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114000875","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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