Determination of the Mathematical Dependence of the Black Liquor Density on the Dry Matter Content (High Yield Softwood Pulp)
DOI:
https://doi.org/10.37482/0536-1036-2021-1-192-200Keywords:
high yield sulphate pulp, chemical recovery, black liquor physical properties, dry matter content, black liquor density, evaporation, mathematical modelAbstract
A modern evaporator station is an energy-saving production of evaporated liquor with high dry matter content for ensuring the minimum SO2 emissions from the soda recovery boiler. Such stations are equipped with Falling Film devices and consist of 5–7 stages. The necessity to improve and create new black liquor concentrators is driven by the increased attention to environmental issues and the wish to produce liquor with a higher calorific value. The physical properties of black liquor depend on its composition and have a significant impact on the selection and design of evaporators. The main properties considered in the evaporation and combustion processes are density, viscosity, surface tension, heating value and boiling temperature. One of the most important characteristics of the liquor evaporation is its viscosity, since it determines the ability of the liquor to pump and affects the design features. Another equally important characteristic is density. With its help, the dry matter content and evaporation process in the main stages of the liquor regeneration are regulated. The study was carried out to determine the mathematical dependence of the black liquor density on the dry matter content for high yield softwood pulp. The study objectives were the following: analyze the effect of the dry matter temperature and concentration on the density of black liquor obtained from cooking high yield softwood pulp according to the technological flow of production; develop a mathematical model of dependence of the black liquor density of high yield sulphate softwood pulp on the concentration and temperature; conduct the TAPPI comparative testing of the results of mathematical and correlation dependences. A mathematical dependence of the black liquor density on the temperature and dry matter content required for immediate technological calculations of chemical regeneration departments in sulphate production of semi-finished products for cardboard was obtained. The following equation of mathematical dependence based on the conducted research, regression analysis, and mathematical processing of the results was obtained: ρ = 0.974 + 0.0071x – 0.0002t – 0.000007xt – 0.00000045t2 – 0.0000045x2 (where ρ – density, g/cm3; x – dry matter content, %; t – temperature, °C). It allows calculating with the highest accuracy the density of black liquor obtained from cooking high yield softwood sulphate pulp. Comparative testing of the results of the developed mathematical dependence and correlation dependence (published by TAPPI) of black liquor density on the dry matter content was carried out. A high level of comparability of the proposed mathematical equations was found.
For citation: Sevastyanova Yu.V., Toptunov Е.А., Shcherbak N.V., Solntsev P.V. Determination of the Mathematical Dependence of the Black Liquor Density on the Dry Matter Content (High Yield Softwood Pulp). Lesnoy Zhurnal [Russian Forestry Journal], 2021, no. 1, pp. 192–200. DOI: 10.37482/0536-1036-2021-1-192-200
Downloads
References
Богомолов Б.Д., Сапотницкий С.А., Соколов О.М. и др. Переработка сульфатного и сульфитного щелоков. М.: Лесн. пром-сть, 1989. 360 с. [Bogomolov B.D., Sapotnitskiy S.A., Sokolov O.M. et al. Processing of Sulphate and Sulphite Liquors. Moscow, Lesnaya promyshlennost’ Publ., 1989. 360 p.].
Волков А.Д., Григорьев Г.П. Физические свойства щелоков целлюлозного производства. Изд. 2-е, доп. и перераб. М.: Лесн. пром-сть, 1970. 120 с. [Volkov A.D., Grigor’yev G.P. Physical Properties of Pulp Production Liquors. Moscow, Lesnaya promyshlennost’ Publ., 1970. 120 p.].
Горбовский Б.Г. Устройство и обслуживание выпарных станций сульфат-целлюлозного производства: пособие для мастеров и выпарщиков. М.; Л.: Гослесбумиздат, 1953. 189 с. [Gorbovskiy B.G. Design and Maintenance of Evaporation Stations of Sulphate Pulp Production. Moscow, Goslesbumizdat Publ., 1953. 189 p.].
ГОСТ 8.234–2013. Государственная система обеспечения единства измерений. Меры вместимости стеклянные. Методика поверки. Дата введ. 2015–07–01. М.: Стандартинформ, 2014. 11 с. [State Standard. GOST 8.234–2013. State System for Ensuring the Uniformity of Measurements. Volumetric Glass Ware. Verification Procedure. Moscow, Standartinform Publ., 2014. 11 p.].
Григорай О.Б., Иванов Ю.С., Комиссаренков А.А., Смолин А.С. Переработка черных щелоков сульфатного производства. СПб.: СПбГТУРП, 2012. 106 с. [Grigoray O.B., Ivanov Yu.S., Komissarenkov A.A., Smolin A.S. Processing of Black Liquors of Sulphate Production. Saint Petersburg, SPb STUPP Publ., 2012. 106 p.].
Гурьев А.В., Казаков Я.В., Комаров В.И., Хованский В.В. Практикум по технологии бумаги / под ред. проф. В.И. Комарова. Архангельск: Изд-во АГТУ, 2001. 112 с. [Gur’yev A.V., Kazakov Ya.V., Komarov V.I., Khovanskiy V.V. Laboratory Course on Paper Technology. Arkhangelsk, ASTU Publ., 2001. 112 p.].
Миловидова Л.А., Комарова Г.В. Производство сульфатной целлюлозы. Архангельск: Изд-во АГТУ, 2001. 31 с. [Milovidova L.A., Komarova G.V. Production of Sulphate Pulp. Arkhangelsk, ASTU Publ., 2001. 31 p.].
Миловидова Л.А., Севастьянова Ю.В., Комарова Г.В., Дубовый В.К. Регенерация химикатов в производстве сульфатной целлюлозы (каустизация и регенерация извести). Архангельск: САФУ, 2010. 157 с. [Milovidova L.A., Sevastyanova Yu.V., Komarova G.V., Dubovyy V.K. Recovery of Chemicals in the Production of Sulphate Pulp (Lime Caustization and Regeneration). Arkhangelsk, NArFU Publ., 2010. 157 p.].
Свидетельство № 411 о метрологической аттестации МВИ. Метод определения массовой доли сухих веществ в черном щелоке. ВНИИБ. Л., 1991. 4 с. [Certificate No. 411 on Metrological Certification of Measurement Procedures. Method for Determining the Mass Fraction of Solids in Black Liquor. All-Russian Scientific Research Institute of Pulp and Paper Industry, 1991. 4 p.].
Селянина Л.И., Селянина С.Б., Кутакова Н.А. Технология сульфатных щелоков. Архангельск: Изд-во АГТУ, 2002. 37 с. [Selyanina L.I., Selyanina S.B., Kutakova N.A. Sulphate Liquor Technology. Arkhangelsk, ASTU Publ., 2002. 37 p.].
Справочник бумажника: в 3 т. 2-е. изд. перераб. и доп. Т. 1. М.: Лесн. промсть, 1964. 841 с. [Handbook for Paper Industry Workers. In 3 vol. Vol. 1. Moscow, Lesnaya promyshlennost’ Publ., 1964. 841 p.].
Элконин Н.В. Изучение свойств отработанных растворов производства целлюлозы сульфатным методом. М.: Бум. пром-сть, 1941. № 2. 21 с. [Elkonin N.V. Study of Properties of Spent Solutions of Pulp Production by Kraft Method. Moscow, Bumazhnaya promyshlennost’ Publ., 1941, no. 2. 21 p.].
Adams T. Sodium Salt Scaling in Black Liquor Evaporators and Concentrators. Tappi Journal, 2001, vol. 84(6), pp. 1–18.
Andreuccetti M.T., Leite B.S., Hallak d´Angelo J.V. Eucalyptus Black Liquor – Density, Viscosity, Solids and Sodium Sulfate Contents Revisited. O Papel, 2011, vol. 72, no. 12, pp. 52–57.
Bayuadri C., Verril C.L., Rousseau R.W. Stability of Sodium Sulfate Dicarbonate in Black Liquor Concentrators. TAPPI Engineering, Pulping and Environmental Conference Proceedings. TAPPI Press, 2006.
Bialik M.A., Theliander H., Sedin P., Verril C.L., DeMartini N. Solubility and Solid Phase Composition in Boiling-Temperature Na2CO3–Na2SO4 Solutions: A Modeling Approach. TAPPI Engineering, Pulping and Environmental Conference Proceedings. TAPPI Press, 2007, pp. 1471–1498.
Cardoso M., Oliveira E.D., Passos M.L.A. Kraft Black Liquor of Eucalyptus from Brazilian Mills. O Papel, 2006, vol. 67, no. 2, pp. 57–83.
Clay D.T. Evaporation Principles and Black Liquor Properties. TAPPI Kraft Recovery Short Course. TAPPI, 2011, pp. 3.1-1–3.1-6. Available at: https://www.tappi.org/content/events/08kros/manuscripts/3-1.pdf (accessed 18.03.20).
Holmlund K., Parviainen K. Evaporation of Black Liquor. Ch. 12. Chemical Pulping.Ed. by J. Gullichsen, C.-J. Fogelholm. Helsinki, Fapet Oy, 1999, pp. B37–B93.
