Japan pyrolysis developing

Mitsui Engineering and Shipbuilding Co., Ltd. (MES) of Japan has developed and commercialized a pyrolysis process for processing municipal solid waste (Figure 4.1). The process,... 

The pattern of commercial production of 1,3-butadiene parallels the overall development of the petrochemical industry. Since its discovery via pyrolysis of various organic materials, butadiene has been manufactured from acetylene as weU as ethanol, both via butanediols (1,3- and 1,4-) as intermediates (see Acetylene-DERIVED chemicals). On a global basis, the importance of these processes has decreased substantially because of the increasing production of butadiene from petroleum sources. China and India stiU convert ethanol to butadiene using the two-step process while Poland and the former USSR use a one-step process (229,230). In the past butadiene also was produced by the dehydrogenation of / -butane and oxydehydrogenation of / -butenes. However, butadiene is now primarily produced as a by-product in the steam cracking of hydrocarbon streams to produce ethylene. Except under market dislocation situations, butadiene is almost exclusively manufactured by this process in the United States, Western Europe, and Japan. 

Another development is due to the interest in polychlorodibenzofurans, spurred by their occurrence as environmental contaminants. Polychloro-phenols are manufactured in large amounts (150,000 tons per annum) and find a wide range of uses. The usual method of manufacture involves the hydrolysis of chlorobenzenes, and side reactions, favored by high temperature, can lead to the production of polychlorodibenzofurans and poly-chlorodibenzo-p-dioxins. The Seveso incident is well known." Polychloro-biphenyls are also widely used industrial chemicals, particularly in heat exchange systems, and their pyrolysis leads to the formation of polychloro-dibenzofurans. Polychlorodibenzofurans have also been detected in the fly ash and flue gases of incinerators and industrial heating plants. The most toxic of the polychlorodibenzofurans are 2,3,7,8-tetra-, 1,2,3,7,8-penta-, and 2,3,4,7,8-pentachlorodibenzofuran, and an extensive literature exists on the environmental pollution and the results of human exposure to these substances. A particularly tragic example of the latter occurred in 1968 in the Fukuoka prefecture of Japan after consumption of rice oil contaminated with a commercial polychlorobiphenyl. 

Solvent-Refined Coal Process. In the 1920s the anthracene oil fraction recovered from pyrolysis, or coking, of coal was utilized to extract 35—40% of bituminous coals at low pressures for the purpose of manufacturing low cost newspaper inks (113). Tetralin was found to have higher solvent power for coals, and the I. G. Farben Pott-Broche process (114) was developed, wherein a mixture of cresol and tetralin was used to dissolve ca 75% of brown coals at 13.8 MPa (2000 psi) and 427°C. The extract was filtered, and the filtrate vacuum distilled. The overhead was distilled a second time at atmospheric pressure to separate solvent, which was recycled to extraction, and a heavier liquid, which was sent to hydrogenation. The bottoms product from vacuum distillation, or solvent-extracted coal, was carbonized to produce electrode carbon. Filter cake from the filters was coked in rotary kilns for tar and oil recovery. A variety of liquid products were obtained from the solvent extraction-hydrogenation system (113). A similar process was employed in Japan during Wodd War II to produce electrode coke, asphalt (qv), and carbonized fuel briquettes (115). 

Menges and his successor Professor Michaelis conducted pyrolysis at RWTH-Aachen in an externally heated extruder, up to 430°C, a temperature maximum dictated by materials selection considerations. Early extruder pyrolysis systems were developed by Union Carbide and Japan Steel Works [14],... 

A full-scale pyrolysis-catalytic process in which the catalytic cracking zone is directly connected to the pyrolysis zone was developed in Japan (Fuji Process) [19]. In this process, after separation of PVC and impurities by wet techniques, waste plastics are thermally pretreated at 300°C for dechlorination and then introduced into the pyrolysis reactor and thermally cracked at 400°C. Subsequently, degradation products are fed directly to the fixed-bed reactor using a ZSM-5 catalyst. 

A series of industry-scale processes for recovery of liquid fuel from waste plastics have been developed and applied in countries such as the United States, Japan, Germany and England. Some of the processes, such as the Veba process, the BP process, the Fuji process and the Hunan University process have been applied widely and successfully in industry. Some typical pyrolysis processes are listed in Table 28.6. 

European technology for pyrolysis, gasification, and liquefaction is described in the seventh section. Chapter 30 includes an interesting discussion of why the development of such processes for MSW has not been as rapid in Europe as in the United States or Japan. During the... 

Hitachi Zosen, in its effort to meet the growing needs of modern Japan, started early to develop a new type of "pyrolysis" furnace. Now, with technological difficulties worked out, this product is now ready for the commercial market. The following outline is to acquaint you with this new type of furnace and the technology it represents. 

In this paper, I have tried to acquaint you with our newly developed pyrolysis-incineration system for the disposal of municipal refuse in Japan. 

Another approach has been developed by Shin Tsuge at the University of Nagoya in Japan. His furnace pyrolyzer includes a cool chamber where samples are loaded into a small crucible above the hot zone. Once the sample is in place, the cup is rapidly lowered into the furnace for pyrolysis. 

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