The Experts below are selected from a list of 1794 Experts worldwide ranked by ideXlab platform
Honghi Tran - One of the best experts on this subject based on the ideXlab platform.
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Incremental Lime Kiln Capacity - Maryvale Mill Experience
2020Co-Authors: Murray Ellis, Richard Manning, Honghi Tran, Kristen LockAbstract:Lime production capacity can be a neglected item when increasing pulp production at kraft pulp mills. This issue has recently been experienced at Australian Papers' Maryvale Mill where a mill upgrade required an increase in Kiln capacity from 270 t/day to 330 t/day. This paper describes a systematic approach used to address Lime Kiln capacity constraints. Following a similar process to that described may be beneficial to other kraft pulp mills with Lime Kiln capacity constraints. Benchmarking of Kiln operations identified gaps to optimal Kiln performance given existing equipment limitations. Kiln mass and energy balances identified high Kiln specific energy consumption 9.0 GJ/tonne versus 7.5 GJ/tonne and excessive energy loss in flue gases. Improvement items included stabilising mud feed, increasing flame temperature, improving the dust removal system and optimising the Kiln chain section. Kiln burner desktop modelling was completed by Kiln Flame Systems to help address low flame temperatures, while a new Lime Mud Disc Filter (LMDF) was installed to deliverer consistent high quality mud to the Kiln. In addition, double hung curtain type stainless steel chain was added to the hot end of the chain section and total chain heat transfer area increased as recommended by Jammbco. Sustainable Kiln production has increased 17% to 315 t/day with the completion of this work.
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Impact of cofiring biofuels and fossil fuels on Lime Kiln operation
July 2015, 2015Co-Authors: Richard Manning, Honghi TranAbstract:Lime Kilns are used to calcine Lime mud to produce Lime for reuse in the causticizing plant of pulp mills. With significant increase in fossil fuel costs and the sustained drive to minimize carbon footprint, there has been a great deal of research and development of the biorefinery concept and production of biofuels for use within pulp mills. Several new biofuels will become available, together with traditional mill derived fuels such as tall oil. In considering use of biofuels for replacement of fossil fuels in the Lime Kiln, each fuel has a different impact on Kiln performance. An assessment on Kiln performance can be achieved and compared to either heavy fuel oil or natural gas. In most cases, the Lime Kiln fuels with high oxygen content and moderately low calorific values burn in a similar manner as natural gas; hence, in assessing impact on Kiln performance, production and induced draft fan limits together with Kiln exit gas temperatures need to be considered.
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Global survey on Lime Kiln operation, energy consumption, and alternative fuel usage
August 2011, 2011Co-Authors: Sabrina Francey, Honghi Tran, Niklas BerglinAbstract:In late 2008, a survey on Lime Kiln operation and fuel usage was conducted through questionnaires distributed to pulp mills in nine countries. Responses were received from 59 pulp mills, totaling 67 Lime Kilns. This paper discusses the key findings from the survey with respect to Kiln design parameters, operating data, control strategies, fuel types, energy consumption, and operating issues. Where possible, comparisons were made with findings obtained from a similar survey conducted in 1991. Over the past two decades many improvements have been made in Kiln design and operation. Included are a larger number of Kilns equipped with product coolers and Lime mud dryers, along with changes designed to deliver higher mud dry solids content to the Kiln. However, ring formation and dusting/high dust load remain the major operational issues among the respondents. Although few Kilns have used alternative fuels to date, there is considerable industry interest in their use in the future. About two-thirds of the Kilns have plans for implementing alternative fuels within the next five years.
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global survey on Lime Kiln operation energy consumption and alternative fuel usage
2010 TAPPI PEERS Conference and 9th Research Forum on Recycling; Norfolk VA; United States; 17 October 2010 through 20 October 2010, 2010Co-Authors: Sabrina Francey, Honghi Tran, Niklas BerglinAbstract:A survey on Lime Kiln operation and fuel usage was conducted through questionnaires distributed to pulp mills in nine countries in late 2008. Responses were received from 67 Lime Kilns at 59 pulp m ...
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1D Heat Transfer Model for the Chain Section of a Lime Kiln
2010 14th International Heat Transfer Conference Volume 4, 2010Co-Authors: Michael Massad, Samer Hassan, Masahiro Kawaji, Honghi TranAbstract:This work was aimed at gaining a better understanding of heat transfer within Lime Kilns, by both experiments and detailed modeling of heat transfer phenomena in the chain section. Experiments were conducted using a laboratory mockup of a rotating Kiln to obtain convective heat transfer coefficient data for cooling of a steel rod in dry or wet Lime mud. For moisture contents of 0% and 30%, the mud heat transfer coefficient was determined to be 170 and 320 W/m2 °C, respectively. A 1-D, unsteady heat conduction model was used to predict the temperature variations of all the chain rings in the chain system and calculate the amount of heat transferred by each chain ring to the Lime mud. A thermal model was then developed to predict the steady axial temperature profiles of Lime mud, gas and Kiln wall throughout a rotating Lime Kiln equipped with a typical chain system.Copyright © 2010 by ASME
Niklas Berglin - One of the best experts on this subject based on the ideXlab platform.
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Experiences from feeding and co-firing of lignin powder in a Lime Kiln
2020Co-Authors: Niklas Berglin, Per Tomani, P. Olowson, T. Hultberg, S. PerssonAbstract:A significant part of the fossil fuel oil consumption at a pulp mill today is related to combustion in the Lime Kiln. Therefore, replacing fuel oil with lignin in this application has been one of t ...
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Global survey on Lime Kiln operation, energy consumption, and alternative fuel usage
August 2011, 2011Co-Authors: Sabrina Francey, Honghi Tran, Niklas BerglinAbstract:In late 2008, a survey on Lime Kiln operation and fuel usage was conducted through questionnaires distributed to pulp mills in nine countries. Responses were received from 59 pulp mills, totaling 67 Lime Kilns. This paper discusses the key findings from the survey with respect to Kiln design parameters, operating data, control strategies, fuel types, energy consumption, and operating issues. Where possible, comparisons were made with findings obtained from a similar survey conducted in 1991. Over the past two decades many improvements have been made in Kiln design and operation. Included are a larger number of Kilns equipped with product coolers and Lime mud dryers, along with changes designed to deliver higher mud dry solids content to the Kiln. However, ring formation and dusting/high dust load remain the major operational issues among the respondents. Although few Kilns have used alternative fuels to date, there is considerable industry interest in their use in the future. About two-thirds of the Kilns have plans for implementing alternative fuels within the next five years.
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global survey on Lime Kiln operation energy consumption and alternative fuel usage
2010 TAPPI PEERS Conference and 9th Research Forum on Recycling; Norfolk VA; United States; 17 October 2010 through 20 October 2010, 2010Co-Authors: Sabrina Francey, Honghi Tran, Niklas BerglinAbstract:A survey on Lime Kiln operation and fuel usage was conducted through questionnaires distributed to pulp mills in nine countries in late 2008. Responses were received from 67 Lime Kilns at 59 pulp m ...
Erik Dahlquist - One of the best experts on this subject based on the ideXlab platform.
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system analysis of dry black liquor gasification based synthetic gas production comparing oxygen and air blown gasification systems
Applied Energy, 2013Co-Authors: Muhammad Naqvi, Erik DahlquistAbstract:The black liquor gasification based bio-fuel production at chemical pulp mill is an attractive option to replace conventional recovery boilers increasing system energy efficiency. The present paper studies circulating fluidized bed system with direct causticization using TiO2 for the gasification of the black liquor to the synthesis gas. The advantage of using direct causticization is the elimination of energy-intensive Lime Kiln which is an integral part of the conventional black liquor recovery system. The study evaluates the effects of gasifying medium i.e. oxygen or air, on the fluidized bed gasification system, the synthesis gas composition, and the downstream processes for the synthesis gas conversion to the synthetic natural gas (SNG). The results showed higher synthetic natural gas production potential with about 10% higher energy efficiency using oxygen blown gasification system than the air blown system. From the pulp mill integration perspective, the material and energy balance results in better integration of air blown system than the oxygen blown system, e.g. less steam required to be generated in the power boiler, less electricity import, and less additional biomass requirement. However, the air blown system still requires a significant amount of energy in terms of the synthesis gas handling and gas upgrading using the nitrogen rejection system.
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Energy conversion performance of black liquor gasification to hydrogen production using direct causticization with CO 2 capture
Bioresource Technology, 2012Co-Authors: Muhammad Naqvi, J Yan, Erik DahlquistAbstract:This paper estimates potential hydrogen production via dry black liquor gasification system with direct causticization integrated with a reference pulp mill. The advantage of using direct causticization is elimination of energy intensive Lime Kiln. Pressure swing adsorption is integrated in the carbon capture process for hydrogen upgrading. The energy conversion performance of the integrated system is compared with other bio-fuel alternatives and evaluated based on system performance indicators. The results indicated a significant hydrogen production potential (about 141MW) with an energy ratio of about 0.74 from the reference black liquor capacity (about 243.5MW) and extra biomass import (about 50MW) to compensate total energy deficit. About 867,000tonnes of CO 2 abatement per year is estimated i.e. combining CO 2 capture and CO 2 offset from hydrogen replacing motor gasoline. The hydrogen production offers a substantial motor fuel replacement especially in regions with large pulp and paper industry e.g. about 63% of domestic gasoline replacement in Sweden. © 2012 Elsevier Ltd.
Muhammad Naqvi - One of the best experts on this subject based on the ideXlab platform.
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system analysis of dry black liquor gasification based synthetic gas production comparing oxygen and air blown gasification systems
Applied Energy, 2013Co-Authors: Muhammad Naqvi, Erik DahlquistAbstract:The black liquor gasification based bio-fuel production at chemical pulp mill is an attractive option to replace conventional recovery boilers increasing system energy efficiency. The present paper studies circulating fluidized bed system with direct causticization using TiO2 for the gasification of the black liquor to the synthesis gas. The advantage of using direct causticization is the elimination of energy-intensive Lime Kiln which is an integral part of the conventional black liquor recovery system. The study evaluates the effects of gasifying medium i.e. oxygen or air, on the fluidized bed gasification system, the synthesis gas composition, and the downstream processes for the synthesis gas conversion to the synthetic natural gas (SNG). The results showed higher synthetic natural gas production potential with about 10% higher energy efficiency using oxygen blown gasification system than the air blown system. From the pulp mill integration perspective, the material and energy balance results in better integration of air blown system than the oxygen blown system, e.g. less steam required to be generated in the power boiler, less electricity import, and less additional biomass requirement. However, the air blown system still requires a significant amount of energy in terms of the synthesis gas handling and gas upgrading using the nitrogen rejection system.
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Energy conversion performance of black liquor gasification to hydrogen production using direct causticization with CO 2 capture
Bioresource Technology, 2012Co-Authors: Muhammad Naqvi, J Yan, Erik DahlquistAbstract:This paper estimates potential hydrogen production via dry black liquor gasification system with direct causticization integrated with a reference pulp mill. The advantage of using direct causticization is elimination of energy intensive Lime Kiln. Pressure swing adsorption is integrated in the carbon capture process for hydrogen upgrading. The energy conversion performance of the integrated system is compared with other bio-fuel alternatives and evaluated based on system performance indicators. The results indicated a significant hydrogen production potential (about 141MW) with an energy ratio of about 0.74 from the reference black liquor capacity (about 243.5MW) and extra biomass import (about 50MW) to compensate total energy deficit. About 867,000tonnes of CO 2 abatement per year is estimated i.e. combining CO 2 capture and CO 2 offset from hydrogen replacing motor gasoline. The hydrogen production offers a substantial motor fuel replacement especially in regions with large pulp and paper industry e.g. about 63% of domestic gasoline replacement in Sweden. © 2012 Elsevier Ltd.
K. Saari - One of the best experts on this subject based on the ideXlab platform.
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intelligent control system of an industrial Lime Kiln process
Control Engineering Practice, 2001Co-Authors: Mika Järvensivu, K. Saari, Sirkkaliisa JamsajounelaAbstract:Abstract In the face of strong competition, the pulp and paper industry is aiming at higher profitability through increased productivity and the reduction of costs. In addition, on the global scale the industry is facing increasing market demands for higher product quality, more specialty products and improved production flexibility and environmental protection. Consequently, extensive research is being conducted to improve existing processes. One alternative, which is gaining increasing attention within the industry, is the improved control of existing processes by means of intelligent systems. In this paper, an intelligent Kiln control system is presented. In the system, neural network models are used in conjunction with advanced high-level controllers based on fuzzy logic principles and a novel linguistic equation approach. Finally, the testing results of the system are presented and discussed.
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Intelligent Control System of the Lime Kiln
IFAC Proceedings Volumes, 1999Co-Authors: Mika Järvensivu, Sirkka-liisa Jämsä-jounela, K. SaariAbstract:Abstract Under strong price competition, the pulp and paper industry is aiming higher profitability through increased productivity and reduction of expenses. In addition, the industry meets increasing market demands for improved product quality and environmental protection. Consequently, extensive research is being conducted to determine how to improve existing processes. One alternative among the others, which is gaining increasing concern, is improved control of the existing processes by using intelligent systems. In this paper the results of a field survey made at a modern Finnish pulp mill are presented. In the field survey, the Lime Kiln operation was studied in order to develop an intelligent Kiln control system for maximizing production capacity, minimizing the degree of variation in Lime quality, and reducing energy consumption and flue gas emissions. This paper also describes the structure and functions of the implemented intelligent Kiln control system, as well as the results achieved during the long-term testing period at the plant.
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A field survey of TRS emissions from a Lime Kiln : Careful operation is essential to control emissions
1999Co-Authors: M. Järvensivu, J. Kivivasara, K. SaariAbstract:In future, tighter regulations concerning the reduced sulphur emissions are expected. Therefore, further reduction of the total reduced sulphur (TRS) emissions will be among the great challenges facing the pulp and paper industry during the next decade. In this paper, the results of a 12-month field survey carried out in order to study the TRS emissions from a Lime Kiln are presented. During the field survey, a large amount of process data was gathered and the effects of the operational parameters on the TRS emissions were examined. According to the results, proper control of the Lime mud filter and the Lime Kiln, especially concerning the wash water rate and excess oxygen, is essential in order to ensure a tolerable level of the TRS emissions from the Lime Kiln. Des reglements beaucoup plus restrictifs en matiere de reduction des emissions de soufre sont prevus pour l'avenir. La reduction accrue des emissions de soufre reduit total (SRT) fera donc partie des defis majeurs a relever dans l'industrie des pâtes et papiers au cours de la prochaine decennie. Cet article presente les resultats d'une etude de douze mois sur le terrain visant a analyser les emissions de SRT d'un four a chaux. Lors de cette etude, les nombreuses donnees recueillies ont permis d'analyser les effets des parametres d'exploitation sur les emissions de SRT. Les resultats indiquent qu'il est essentiel de bien controler le filtre de boues de chaux et le four a chaux, surtout en ce qui concerne le debit d'eau de lavage et l'exces d'oxygene, afin d'assurer un niveau tolerable des emissions de SRT du four a chaux.