【導讀】丁二烯的生產方法就世界范圍而言先后經歷了乙醇脫氫法、丁烯催化脫氫法、丁烷催化脫氫法、丁烯氧化脫氫法和乙烯副產C餾分分離法。每生產1噸丁二烯約需消耗3噸乙醇，該方法的經濟性差，目前已被淘汰。水洗塔底溶劑的約1％送往溶劑回收精制系統(tǒng)，以保證循環(huán)溶劑的質量。炔烴由第二萃取蒸餾塔第75塊塔板側線采出，送往接觸冷凝器。第一萃取蒸餾工序、第二萃取蒸餾工序、精餾工序和溶劑回收工序。原料c汽化后進人第一萃取精餾塔．溶劑DMF由塔的上部加入。溶解度小的丁烷、丁烯、c，使丁二烯的相對揮發(fā)度增大，并從塔頂分出，而丁二烯、炔烴等和溶劑一起從塔底導出，進入第一解吸塔被完全解吸出來，冷卻并經螺桿壓縮機壓縮后進人第二萃取精餾塔進一步分離。不含c組分的溶劑從解吸塔底高溫采出，用作萃取精餾、精餾、蒸發(fā)等工序的熱源，熱量回收后重新循環(huán)使用。炔烴、丙二烯、硫化物、羰基化合物這些有害雜質在溶劑中的溶解度較高，為防止乙烯基

　　

【正文】 of dissolved and selective than other solvents, so smaller cycles, solvent solvent consumption is low, 4 no water and no proportion of DMF mutually dissolved, thus avoiding c aromatics extraction tower statified phenomenon, 5 any c distillate with DMF are not formed azeotrope, be helpful for hydrocarbon and solvent separation, but due to its high boiling point solvents, loss, 6 thermal stability and good chemical stability, 7 because of its high boiling point, the extraction and desorption tower operation tower temperature is higher, easy cause double olefins and GuiTing polymerization, No water circumstance of), but in noncorrosive steel under the existing water can depose generate formate and too, so there must be the corrosive. N a methyl pyrrole methodN a methyl pyrrole method (NMP) by BASF pany in Germany, and the successful development of industrial production in 1968. Built a set of million tons/year production equipment. The production process including extraction distillation, degassing and distillation and solvent regeneration process. Thick c fractions gasification lifo drawn, capturing washing water containing 8% of N a methyl pyrrole extraction column by entering, butadiene and easily dissolved ponents and parts of butane and dinitramine, excluding the absorption of butane and yield were from the tower. Wash the bottom of the solvent distillation, solvent into in the absorption of butane and yield were more of butadiene, propylene limonene and acetylene replacement, contains the acetylene and propylene limonene distillation of butadiene extraction from the pores in gaseous after entering wash. The washing tower, with fresh solvent position dissolve and other butadiene by its top after the condensing steam distillation process, liquefied into solvent distillation tower kettle returns through the middle of the rich. The kettle solvent distillation advanced person braising cans of central degas, before entering the degassing tower, and elimination of water balance control NMP. Small GuiTing from lateralline leave degassing tower. The rest of the cooling off into the circulation pressor, finally return column bottom. After washing DaChu e from coarse butadiene in first distillation, in the second removal methyl acetylene distillation tower removal 1,2 a butadiene and c by distillation column, the hydrocarbon butadiene get products. After stripping out the amount of solvent 0,2 % regeneration, lest impurities accumulated. The method is characteristic of NMP: excellent performance, low toxicity solvents, biodegradable, low resistance, (2) raw material, can get a wider range of high quality product purity of butadiene, %, 3 GuiTing c without hydrogenation, simple process, low investment, convenient operation, high economic benefit, (NMP excellent selectivity and dissolve High boiling point ability, the solution of steam, solvent, low loss, 5 thermal stability and chemical stability is extremely good, even happen, its product is trace hydrolysis amp。noncorrosive. Therefore all USES ordinary steel devices. Exactly is the method of butadiene production efficiency is difficult, the consensus is the highest cost dhea catalytic oxidation method, the method of dhea, ethylene plant by byproduct of c is the most expensive fractions separation. C) device, only the price of fuel fraction is obtained, so the cost of butadiene and low dhea law than 30 to 40 percent. From the production scale of ethylene and developing trend of ethylene plant, by byproduct of C fractions butadiene will still be separated, the major source of butadiene oxidation method to pensate dhea is insufficient, ethylene, and catalytic dehydrogenation law basic eliminated. 13