The Experts below are selected from a list of 147 Experts worldwide ranked by ideXlab platform

Keli Chen - One of the best experts on this subject based on the ideXlab platform.

  • pyrolysis behavior of the black liquor derived from soda anthraquinone and soda oxygen pulping of rice straw at different reaction end points
    Energy & Fuels, 2017
    Co-Authors: Lilong Zhang, Keli Chen
    Abstract:

    Black liquor (BL) with inorganic cooking chemicals and combustible material is the alkali and power resources for pulping. For rice straw pulping, BL obtained from soda–anthraquinone (AQ) pulp (SABL) could hardly be combusted in a traditional Recovery Furnace, because of the involvement of a great deal of silica in it. On the contrary, soda–oxygen pulping may have the majority of the silica depositing in pulp owing to the oxidation, instead of its dissolution in the BL (SOBL). The pyrolysis behavior of SOBL was investigated in this paper, and composition and thermal degradation were comparatively studied by elemental analysis and TG-MS/FTIR. The reaction mechanism of pyrolysis of SOBL at different pulping end points is first revealed. The results suggested that SOBL had reasonable silicon content about one-eighth of that of the SABL, and the volatiles can be produced under relatively low temperature. For different reaction end points, with deeper oxidization, more volatiles were released at lower temperature.

  • Pyrolysis Behavior of the Black Liquor Derived from Soda–Anthraquinone and Soda–Oxygen Pulping of Rice Straw at Different Reaction End Points
    Energy & Fuels, 2017
    Co-Authors: Lilong Zhang, Keli Chen
    Abstract:

    Black liquor (BL) with inorganic cooking chemicals and combustible material is the alkali and power resources for pulping. For rice straw pulping, BL obtained from soda–anthraquinone (AQ) pulp (SABL) could hardly be combusted in a traditional Recovery Furnace, because of the involvement of a great deal of silica in it. On the contrary, soda–oxygen pulping may have the majority of the silica depositing in pulp owing to the oxidation, instead of its dissolution in the BL (SOBL). The pyrolysis behavior of SOBL was investigated in this paper, and composition and thermal degradation were comparatively studied by elemental analysis and TG-MS/FTIR. The reaction mechanism of pyrolysis of SOBL at different pulping end points is first revealed. The results suggested that SOBL had reasonable silicon content about one-eighth of that of the SABL, and the volatiles can be produced under relatively low temperature. For different reaction end points, with deeper oxidization, more volatiles were released at lower temperature.

Lilong Zhang - One of the best experts on this subject based on the ideXlab platform.

  • pyrolysis behavior of the black liquor derived from soda anthraquinone and soda oxygen pulping of rice straw at different reaction end points
    Energy & Fuels, 2017
    Co-Authors: Lilong Zhang, Keli Chen
    Abstract:

    Black liquor (BL) with inorganic cooking chemicals and combustible material is the alkali and power resources for pulping. For rice straw pulping, BL obtained from soda–anthraquinone (AQ) pulp (SABL) could hardly be combusted in a traditional Recovery Furnace, because of the involvement of a great deal of silica in it. On the contrary, soda–oxygen pulping may have the majority of the silica depositing in pulp owing to the oxidation, instead of its dissolution in the BL (SOBL). The pyrolysis behavior of SOBL was investigated in this paper, and composition and thermal degradation were comparatively studied by elemental analysis and TG-MS/FTIR. The reaction mechanism of pyrolysis of SOBL at different pulping end points is first revealed. The results suggested that SOBL had reasonable silicon content about one-eighth of that of the SABL, and the volatiles can be produced under relatively low temperature. For different reaction end points, with deeper oxidization, more volatiles were released at lower temperature.

  • Pyrolysis Behavior of the Black Liquor Derived from Soda–Anthraquinone and Soda–Oxygen Pulping of Rice Straw at Different Reaction End Points
    Energy & Fuels, 2017
    Co-Authors: Lilong Zhang, Keli Chen
    Abstract:

    Black liquor (BL) with inorganic cooking chemicals and combustible material is the alkali and power resources for pulping. For rice straw pulping, BL obtained from soda–anthraquinone (AQ) pulp (SABL) could hardly be combusted in a traditional Recovery Furnace, because of the involvement of a great deal of silica in it. On the contrary, soda–oxygen pulping may have the majority of the silica depositing in pulp owing to the oxidation, instead of its dissolution in the BL (SOBL). The pyrolysis behavior of SOBL was investigated in this paper, and composition and thermal degradation were comparatively studied by elemental analysis and TG-MS/FTIR. The reaction mechanism of pyrolysis of SOBL at different pulping end points is first revealed. The results suggested that SOBL had reasonable silicon content about one-eighth of that of the SABL, and the volatiles can be produced under relatively low temperature. For different reaction end points, with deeper oxidization, more volatiles were released at lower temperature.

C.l. Verrill - One of the best experts on this subject based on the ideXlab platform.

  • Three-dimensional kraft Recovery Furnace model: implementation and results of improved black liquor combustion models
    Tappi Journal, 1997
    Co-Authors: R.a. Wessel, Kevin L. Parker, C.l. Verrill
    Abstract:

    A three-dimensional mathematical model of a kraft Recovery Furnace was improved by developing better models of black-liquor combustion. These new models - which describe combustion of black-liquor drops and black-liquor deposits on the Furnace walls and char bed - include mechanisms for sodium sulfate reduction and carbon removal by CO 2 and H 2 O gasification. Black-liquor combustion is fully coupled to the solution for gas-phase combustion and turbulent flow in the Furnace. Predicted black-liquor combustion patterns are presented for a commercial-scale Recovery Furnace, including chemical species distributions, temperature maps, and component reaction rates for char burning and smelt reduction. Carbon removal rates for gasification, oxidation, and sulfate reduction are compared and evaluated for entrained particles, Furnace walls, and the char bed. Predicted smelt-reduction efficiencies are compared with commercial performance. Application : better models of black-liquor combustion provide more realistic simulations of the kraft Recovery Furnace.

  • High-solids black liquor firing in pulp and paper industry Kraft Recovery boilers. Final report, Phase 1, Volume 1: Executive summary
    1995
    Co-Authors: W.t. Southards, C.l. Verrill, J.l. Clement, R.a. Mcilroy, M.r. Tharp, R.a. Wessell
    Abstract:

    This project is a multiple-phase effort to develop technologies to improve high-solids black liquor firing in pulp mill Recovery boilers. The objectives are to develop a preliminary design of a Recovery Furnace simulator; evaluate the economics of high-solids; and delineate a project concept for evaluating candidate technologies to improve chemical Recovery.

  • High-solids black liquor firing in pulp and paper industry kraft Recovery boilers: Phase 1 -- Final report. Volume 2: Project technical results
    1995
    Co-Authors: W.t. Southards, C.l. Verrill, J.l. Clement, R.a. Mcilroy, M.r. Tharp, R.a. Wessell
    Abstract:

    This project is a multiple-phase effort to develop technologies to improve high-solids black liquor firing in pulp mill Recovery boilers. The principal means to this end is to construct and operate a pilot-scale Recovery Furnace simulator (RFS) in which these technologies can be tested. The Phase 1 objectives are to prepare a preliminary design for the RFS, delineate a project concept for evaluating candidate technologies, establish industrial partners, and report the results. Phase 1 addressed the objectives with seven tasks: Develop a preliminary design of the RFS; estimate the detailed design and construction costs of the RFS and the balance of the project; identify interested parties in the paper industry and key suppliers; plan the Phase 2 and Phase 3 tests to characterize the RFS; evaluate the economic justification for high-solids firing deployment in the industry; evaluate high-solids black liquor property data to support the RFS design; manage the project and reporting results, which included planning the future program direction.

P. Uronen - One of the best experts on this subject based on the ideXlab platform.

  • Modelling, simulation and control of a lime circulation loop
    IFAC Proceedings Volumes, 2018
    Co-Authors: P. Uronen, H. Aurasmaa, Kauko Leiviskä
    Abstract:

    This research work is a part of a greater development project still continuing in the University of Oulu. The target of this project is to develop a hierarchical control system for a sulphate mill Recovery system. The two main parts of the overall Recovery system are the Recovery Furnace and the lime circulation loop. This report concentrates on the lime circulation loop including the causticization plant and the lime kiln.

  • Advanced Process Control Minimizes Kraft Mill Effluents
    IFAC Proceedings Volumes, 2017
    Co-Authors: P. Uronen, H. Aurasmaa, Kauko Leiviskä
    Abstract:

    Abstract In recent years the pulp industry, like any other industry, has been obliged to pay more attention to the problem of effluents. For the most part this has been necessary in order to meet legislative requirements; but the chemical and energy losses due to these effluents are in themselves considerable enough to make their minimization important. This paper presents the results and experiences gained in co-operative projects with the University of Oulu and the Finnish Pulp Industry. The target in these projects has been to develop comprehensive models and advanced control systems for different processes in kraft mills. As a result of these projects the first computer control system in Finland for a Recovery boiler has now been in operation since spring 1976 and the first system for a causticizing plant and lime kiln will be implemented in the very near future. In the development of these systems special attention has also been paid to emission monitoring and control. The experiences gained from the Recovery Furnace system show a remarkable decrease in S02 and H2S emissions, for example. A detailed description of the Recovery control system with practical experiences will be given.

  • The premises for a computer based production control system of a sulphate pulp mill
    Computers & Chemical Engineering, 2001
    Co-Authors: Kauko Leiviskä, H. Aurasmaa, P. Uronen
    Abstract:

    Abstract The considerable benefits gained in recent years through computer control of pulp digesting and bleaching have encouraged the development of corresponding systems for the energy section and for the processes used in the chemical circulation in the pulp mill, namely the Recovery Furnace, the causticization plant and the lime kiln. This development has led to the need for development of higher level co-ordinating systems in order to assure the overall optimal operation of the mill. This paper deals with the newest process control systems and outlines the functions of the production control and management information system.

Kauko Leiviskä - One of the best experts on this subject based on the ideXlab platform.

  • Modelling, simulation and control of a lime circulation loop
    IFAC Proceedings Volumes, 2018
    Co-Authors: P. Uronen, H. Aurasmaa, Kauko Leiviskä
    Abstract:

    This research work is a part of a greater development project still continuing in the University of Oulu. The target of this project is to develop a hierarchical control system for a sulphate mill Recovery system. The two main parts of the overall Recovery system are the Recovery Furnace and the lime circulation loop. This report concentrates on the lime circulation loop including the causticization plant and the lime kiln.

  • Advanced Process Control Minimizes Kraft Mill Effluents
    IFAC Proceedings Volumes, 2017
    Co-Authors: P. Uronen, H. Aurasmaa, Kauko Leiviskä
    Abstract:

    Abstract In recent years the pulp industry, like any other industry, has been obliged to pay more attention to the problem of effluents. For the most part this has been necessary in order to meet legislative requirements; but the chemical and energy losses due to these effluents are in themselves considerable enough to make their minimization important. This paper presents the results and experiences gained in co-operative projects with the University of Oulu and the Finnish Pulp Industry. The target in these projects has been to develop comprehensive models and advanced control systems for different processes in kraft mills. As a result of these projects the first computer control system in Finland for a Recovery boiler has now been in operation since spring 1976 and the first system for a causticizing plant and lime kiln will be implemented in the very near future. In the development of these systems special attention has also been paid to emission monitoring and control. The experiences gained from the Recovery Furnace system show a remarkable decrease in S02 and H2S emissions, for example. A detailed description of the Recovery control system with practical experiences will be given.

  • The premises for a computer based production control system of a sulphate pulp mill
    Computers & Chemical Engineering, 2001
    Co-Authors: Kauko Leiviskä, H. Aurasmaa, P. Uronen
    Abstract:

    Abstract The considerable benefits gained in recent years through computer control of pulp digesting and bleaching have encouraged the development of corresponding systems for the energy section and for the processes used in the chemical circulation in the pulp mill, namely the Recovery Furnace, the causticization plant and the lime kiln. This development has led to the need for development of higher level co-ordinating systems in order to assure the overall optimal operation of the mill. This paper deals with the newest process control systems and outlines the functions of the production control and management information system.