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Show TECHNOLOGIES TO INCRE·ASE THE EFFICIENT USE OF ENERGY IN THE PROCESS INDUSTRIES J. H. Pohl w. S. Lanier Energy and Environmental Research Corporation Energy and Environmental Research Corp. Irvine, California, USA Chapel Hill, North Carolina, USA J. Keller J. Patton R. Jain EG&G Idaho Inc. Idaho Falls, Idaho, USA U.S. Department of Energy Idaho Falls, Idaho, USA U.S. Department of Energy Washington, D.C., USA ABSTRACT This study identified innovative research areas which will conserve industrial energy and improve fuel flexibility within the next ten years. The approach taken was, first to identify major industrial users of energy. Second, to characterize industrial processes so that research work on specific processes could be extended to other processes. Third, to identify research topics, establish the status of the technology, investigate technological and institutional barriers to implementing the technology, and to evaluate the savings and economics of installing the technology. Initially, 144 potential research topics were identified. These were screen to 32 topics. The 32 research topics were evaluated for energy saving and economics of implementation. Fifteen research topics which could economically save industrial energy and improve fuel flexibility were identified. Of these, topics two 1) Combustion of low Btu wastes 2) Furnace design, heat transfer and mixing patterns were more attractive economically than others and could save 500 BOE/yr-dollar research and 350 BOE/yr-dollar research, respectively. Immediate consideration could be given to funding these two topics. INDUSTRY USES 40 PERCENT of the energy in the United States. As much as 1100 MBOE/yr of this energy might be saved or switched to a more abundant fuel (1). This paper recommends promising research topics which could be implemented within ten years and could result in major fuel savings or flexibility. A previous report identified technologies which could be applied in five years (2). Technologies were specified by first identifying major industrial users of energy. Second, a comprehensive approach to evaluating 313 the potential energy savings was used to classify industrial processes, identify technologies, screen the technologies, and establish the research priorities. APPROACH - Figure 1 shows the approach used in this paper to identify and evaluate technologies to conserve industrial energy. First, industrial processes were categorized into processes to which similar energy savings technologies might be applied. Second, energy conservation technologies were identified. Third, these energy technologies were screened by combustion experts to establish the most promising technologies. Finally, the technologies were evaluated to determine energy savings, economics, and funding priority. GENERIC INDUSTRIAL PROCESSES - Industrial processes were classified by the parameters which control the application of energy saving technologies. The processes were classified by: • Process temperature • Batch vs. continuous • Direct vs. indirect heating • Allowable temperature variation • Fuel • Firing method The process temperature dictates the exit temperature and hence the available energy in the stack gas. Process temperatures are controlled to produce a desired change in the product. For instance, Figure 2 shows the temperatures to which iron must be heated to obtain desired changes at equilibrium. The heating, holding, and quenching times for steel processing can be altered to produce products different than those predicted by equilibrium. Typical temperatures for a number of industrial products and processes are shown in Table 1. Continuous processes are more energy efficient than batch processes because inert parts of the process do not have to be heated each cycle. However, batch processes continue to be used because of ease of control. Examples are soaking pits and aluminum melting. Direct heating is more efficient than |