Usable excess heat in future kraft pulp mills.Application: This information can help mills make an informed decision in the design phase of a retrofit ret·ro·fit v. ret·ro·fit·ted or ret·ro·fit, ret·ro·fit·ting, ret·ro·fits v.tr. 1. To provide (a jet, automobile, computer, or factory, for example) with parts, devices, or equipment not in . New environmental objectives will lead to changes in the future pulp and paper industry The global pulp and paper industry is dominated by North American (United States, Canada), northern European (Finland, Sweden) and East Asian countries (such as Japan). Australasia and Latin America also have significant pulp and paper industries. , water loop closures, new processes to remove non-process elements (NPE NPE NullPointerException (Java) NPE Network Processing Engine NPE National Policy on Education NPE National Plastics Exposition NPE Natural Penis Enlargement NPE Nutrition Program for the Elderly ), and reduced fossil fuel fossil fuel: see energy, sources of; fuel. fossil fuel Any of a class of materials of biologic origin occurring within the Earth's crust that can be used as a source of energy. Fossil fuels include coal, petroleum, and natural gas. consumption are possible results of these neat objectives. A first step toward reducing the fuel consumption in a mill is to energy-integrate existing processes. Then, by designing the secondary heat system differently, medium temperature (70[degrees]C-100[degrees]C) heat can be made available and used in the plant to replace live steam through process modification, thus further decreasing fuel consumption. With a higher temperature where heat can be made available, a commensurate amount of live steam can be replaced. The amount of heat that can be made available varies among mills. We investigated two model mills producing market pulp (2000 a.d. metric tons/day) to help quantify the expected amounts. Two different secondary heat systems are shown for each model mill, one reference design and one novel design where excess heat is made available. The heat made available in these model mills is used in fine evaporation evaporation, change of a liquid into vapor at any temperature below its boiling point. For example, water, when placed in a shallow open container exposed to air, gradually disappears, evaporating at a rate that depends on the amount of surface exposed, the humidity plant to replace live steam. The investment cost for the novel secondary heat system making heat available and for using that heat in the evaporation plant compared to the investment cost for the reference system is between US$ 5-10 million for the two model mills. The total heat demand for the plant is lowered up to 17% when using the heat made available in the evaporation plant to replace live steam. That, together with the extra investment cost, results in a profit of US$ 0.6-1.5 million/year. S! Wising is a Ph.D. student and Berntsson is professor in the Department of Heat and Power Technology, Chalmers University of Technology (body, education) Chalmers University of Technology - A Swedish university founded in 1829 offering master of science and doctoral degrees. Research is carried out in the main engineering sciences as well as in technology related mathematical and natural sciences. , 412 96 Goteborg, Sweden; Asblad is with CIT n. 1. A citizen; an inhabitant of a city; a pert townsman; - used contemptuously. Which past endurance sting the tender cit. - Emerson. Industriell Energianalys AB, 412 88 Goteborg, Sweden; email Wising at ulrika.wising@hpt.chalmers.se. |
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