化工专业外文翻译

1、第 1 章 外文翻译的基本内容丁二烯的生产方法就世界范围而言先后经历了乙醇脱氢法、丁烯催化脱氢法、丁烷催化脱氢法、丁烯氧化脱氢法和乙烯副产c 馏分分离法。1乙醇催化脱氢法 乙醇催化脱氢生产丁二烯的方法1928年首先在原苏联工业化，该方法以氧化镁和氧化硅为催化剂反应产物除生成丁二烯外还生成乙醛、乙醚、高级醇等多种副产品。每生产1吨丁二烯约需消耗3吨乙醇，该方法的经济性差，目前已被淘汰。2丁烯催化脱氢法 丁烯催化脱氢生产丁二烯首先由美国新泽西美孚石油开发公司开发。1943年第一套工业化装置投产随后shell和dow公司也开发成功新的催化剂，从而也产生了shel工艺和dow工艺，该方法的工业化使得丁

2、二烯的生产由酒精为原料转为以石油为原料。丁烯催化脱氢过程中，原料丁烯需混合大量水蒸汽以降低烃分压，来提高丁烯的转化率及生成丁二烯的选择性。该方法以dow工艺的丁烯转化率和丁二烯的选择性为最高，分别达到3545和90 -94 。3丁烷催化脱氢法 丁烷的来源要比丁烯丰富，价格也便宜，除可来自乙烯副产c 馏分外，还可来自天然气及油田气。 丁烷催化脱氢有一步法和两步法两种工艺： houdry一步法生产工艺由美国houdry公司开发，1959年工业化，该工艺的催化剂经改进后，在美国及其他国家得到广泛应用。houdry工艺丁烷一步脱氢采用由1820氧化铬浸渍的氧化铝作催化剂，过程无需用水蒸气稀释原料，反应

3、沉积在催化剂表面的结炭在催化剂再生过程中再用空气烧去，总收率为62-63。philips两步法生产工艺由美国philips公司开发，1953年工业化，该方法丁烷转化率为30，总收率为5060。此外，原苏联也于1960-1963年开发了类似philips的两步法工艺。由于两步法流程较长操作复杂，故其应用远没有一步法广泛。4丁烯氧化脱氢法氢由于受反应平衡影响单程转化率不高，为了使平衡向着有利于生产丁二烯的方向，可用氧脱去反应生成的氢，这样便可以大幅度提高丁烯的转化率及生成丁二烯的选择性。这一工艺由美国petrotex公司在1965年首先工业化随后许多催化脱氢工厂将其改为氧化脱氢生产丁二烯。氧化脱氢

4、生产丁二烯单程转化率达70选择性为80-92。我国在60年代开发成功丁烯氧化脱氢生产丁二烯技术，成为当时我国丁二烯生产的主要方法。5由乙烯装置副产c 馏分中分离丁二烯 石油烃蒸汽裂解是生产乙烯、丙烯、丁二烯等的重要方法，在分离乙烯和丙烯的同时分离出裂解c 馏分，其中含有大量的丁二烯，是目前生产丁二烯的主要原料，而由c 馏分分离丁二烯则是目前生产丁二烯的主要方法当前世界绝大多数丁二烯产品是用这一方法生产的。由于c 馏分中各组分的沸点比较接近，需采用萃取精馏方可将丁二烯分离出来。由于使用溶剂的不同而有以下不同方法：糠醛法、乙腈法、二甲基甲酰胺法、二甲基乙酰胺法、n一甲基吡咯烷酮法等。在工业上得到广

5、泛使用的是乙腈法、二甲基甲酰胺法和n一甲基吡咯烷酮法。51乙腈法 该法最早由美国shell公司开发成功， 并于1956年实现工业化生产。它以含水10的乙腈(ac 为溶剂，由萃取、闪蒸、压缩、高压解吸、低压解吸和溶剂回收等工艺单元组成。1977年shel公司在改造中增加了冷凝器和水洗塔，并将闪蒸和低压解吸的气相合并压缩其中约8经冷凝送往水洗塔洗去溶剂，塔顶气相返回原料蒸馏塔，这样就除去了c 烃中的c 烃。其余气体一部分送往高压解吸塔另一部分作为再沸气体送往萃取蒸馏塔塔底以提供热能从而省去了一台再沸器，降低了蒸汽用量。水洗塔底溶剂的约1送往溶剂回收精制系统，以保证循环溶剂的质量。对炔烃含量较高的原

6、料需要进行加氢处理，或采用精密精馏、两段萃取才能得到纯度较高的丁二烯。目前，该方法以意大利sir工艺和日本jsr工艺为代表。 意大利sir工艺以含水5的acn为溶剂，采用5塔流程(氨洗塔、第一萃取精馏塔、第二萃取精馏塔、脱轻塔和脱重塔)。在第一萃取精馏塔前加一氨水洗涤塔，用以除去原料中004008(质量百分数)的醛酮。炔烃由第二萃取蒸馏塔第75块塔板侧线采出，送往接触冷凝器。脱重塔塔底和接触冷凝器底部物料合并，其热能回收后用于原料蒸发器。该工艺不仅能使丁二烯收率达到9698还能使丁二烯与炔烃分离，丁二烯产品纯度可以达到995以上。该技术的特点是流程简单，溶剂解吸在萃取精馏塔下段完成；第一萃取精

7、馏塔采用两点进料，有利于改善塔内液相的浓度分布减少该塔上段的液相负荷，降低能耗；在第一萃取精馏塔下部设置一台换热器，起中间再沸器的作用，可充分利用塔底热能提高烃类从溶剂中的分离效率；采用在第二萃取精馏塔第75块塔板侧线除炔烃的技术，使丁二烯与炔烃几乎完全分离。 日本irs工艺以含水10的acn 为溶剂，采用两段萃取蒸馏，第一萃取蒸馏塔由两塔串联而成。该工艺经过了1980年和1988年两次重大的改造 。1980年的改造采用热偶合技术，即将第二萃取蒸馏塔顶全部富含丁二烯的蒸汽不经冷凝直接送入脱重塔中段同时将脱重塔内下降液流的一部分从中段塔盘上抽出，送往第二萃取蒸馏塔作为塔顶回流液，这样第二萃取蒸馏

8、塔塔顶不需要冷凝器，这部分的热量将全部加到脱重塔，使该塔塔底再沸器的热负荷比热偶合前降低40左右，从而实现大幅度节能。1988年的改造主要解决系统热能回收问题即在提浓塔和脱轻塔安装中间冷凝器，将提浓塔从进料板附近上、下两段串联相接，这样即可使上塔负荷大幅度降低，又不会影响塔的操作条件。将塔分为上下两段，下塔操作压力提高塔内温度相应升高，这样中间冷凝器就可回收到高品位的热能。此外，溶剂回收塔塔底废水的热能，可用于该塔进料管线的预热器，加上解析塔从侧线采出炔烃也可回收部分热能，因而该工艺在同类工艺中的能耗是最低的采用acn法生产丁二烯的特点是：沸点低，萃取、汽提操作温度低，易防止丁二烯自聚；汽提可

9、在高压下操作，省去了丁二烯气体压缩机，减少了投资；粘度低，塔板效率高，实际塔板数少；毒性微弱，在操作条件下对碳钢腐蚀性小；丁二烯分别与正丁烷、丁二烯二聚物等形成共沸物，溶剂精制过程复杂，操作费用高；蒸汽压高，随尾气排出的溶剂损失大；用于回收溶剂的水洗塔较多，相对流程长。52二甲基甲酰胺法 二甲基甲酰胺法(dmf法)又名gpb法，由日本瑞翁公司于1965年实现工业化生产，并建成一套45万吨年生产装置。该生产工艺包括四个工序，即第一萃取蒸馏工序、第二萃取蒸馏工序、精馏工序和溶剂回收工序。原料c 汽化后进人第一萃取精馏塔溶剂dmf由塔的上部加入。溶解度小的丁烷、丁烯、c，使丁二烯的相对挥发度增大，并

10、从塔顶分出，而丁二烯、炔烃等和溶剂一起从塔底导出，进入第一解吸塔被完全解吸出来，冷却并经螺杆压缩机压缩后进人第二萃取精馏塔进一步分离。不含c 组分的溶剂从解吸塔底高温采出，用作萃取精馏、精馏、蒸发等工序的热源，热量回收后重新循环使用。炔烃、丙二烯、硫化物、羰基化合物这些有害杂质在溶剂中的溶解度较高，为防止乙烯基乙炔爆炸，并进一步回收溶剂中的丁二烯，第二萃取塔底排出的富溶剂送往丁二烯回收塔，塔顶为粗丁二烯。回收塔塔顶馏出的丁二烯和少量杂质返回第二萃取塔前的压缩机人口，塔釜含炔烃的溶剂送至第二解吸塔，从该塔塔顶分出乙烯基乙炔，稀释后用作锅炉燃料，釜液为溶剂，循环回萃取精馏塔。经两段萃取精馏得到的粗

11、丁二烯中的杂质采用普通精馏除去。比丁二烯挥发度大的c，、水分等，在脱轻塔顶除去，比丁二烯挥发度小的残余2一丁烯、1，2-丁二烯、c 以及在生产过程中产生的少量丁二烯二聚物在脱重塔塔底除去。脱重塔顶可以得到纯度在995以上的聚合级丁二烯。 dmf法工艺的特点是：对原料c 的适应性强，丁二烯含量在15-60范围内都可生产出合格的丁二烯产品； 生产能力大，成本低，工艺成熟，安全性好、节能效果较好，产品、副产品回收率高达97； 由于dmf对丁二烯的溶解能力及选择性比其他溶剂高，所以循环溶剂量较小，溶剂消耗量低；无水dmf可与任何比例的c 馏分互溶，因而避免了萃取塔中的分层现象；dmf与任何c 馏分都不

12、会形成共沸物，有利于烃和溶剂的分离，但由于其沸点较高，溶剂损失小；热稳定性和化学稳定性良好； 由于其沸点高，萃取塔及解吸塔的操作温度都较高，易引起双烯烃和炔烃的聚合；无水情况下对碳钢无腐蚀性，但在水分存在下会分解生成甲酸和二甲胺，因而有一定的腐蚀性。53 n一甲基吡咯烷酮法 n一甲基吡咯烷酮法(nmp法)由德国basf公司开发成功，并于1968年实现工业化生产建成一套75万吨年生产装置。其生产工艺主要包括萃取蒸馏、脱气和蒸馏以及溶剂再生工序。粗c 馏分气化后进入主洗涤塔底部，含有8水的n一甲基吡咯烷酮萃取剂由塔顶进入，丁二烯和更易溶解的组分及部分丁烷和丁烯被吸收，同时不含丁二烯的丁烷和丁烯从塔

13、顶排出。主洗塔底部的富溶剂进入精馏塔，在此溶剂吸收的丁烷和丁烯被更易溶的丁二烯、丙二烯和乙炔置换出来，含有乙炔和丙二烯的丁二烯从精馏塔侧线以气态采出进入后洗塔。在后洗塔中，用新鲜溶剂将其他组分溶解，粗丁二烯由其塔顶蒸出后冷凝液化进入蒸馏工序，塔釜富溶剂返回精馏塔的中段。精馏塔釜的富溶剂先进人闪蒸罐中部脱气，再进入脱气塔脱烃，并控制nmp中的水平衡少量炔烃从侧线离开脱气塔。其余脱下的烃经冷却塔进入循环压缩机，最后返回精馏塔底部。从后洗塔出来的粗丁二烯在第一蒸馏塔脱除甲基乙炔，在第二蒸馏塔中脱除1，2一丁二烯和c 烃，由第二蒸馏塔顶得到丁二烯产品。汽提后的溶剂抽出总量的0，2进行再生，以免杂质积累

14、。nmp法工艺的特点是：溶剂性能优良，毒性低，可生物降解，腐蚀性低；原料范围较广，可得到高质量的丁二烯，产品纯度可达97-999；c炔烃无需加氢处理，流程简单，投资低，操作方便，经济效益高；nmp具有优良的选择性和溶解能力，沸点高、蒸汽压低，因而运转中溶剂损失小；热稳定性和化学稳定性极好，即使发生微量水解，其产物也无腐蚀性。因此装置可全部采用普通碳钢。确切地比较各种丁二烯生产方法的经济性是困难的，比较一致的看法是催化脱氢法的成本最高，氧化脱氢法次之，由乙烯装置副产的c 馏分分离法最为便宜。乙烯装置副产c 馏分只相当燃料的价格，因此分离得到丁二烯的成本比脱氢法低30-40。从目前乙烯的生产规模及

15、发展趋势来看，由乙烯装置副产的c 馏分分离丁二烯仍将是丁二烯的主要来源，氧化脱氢法只是用来弥补乙烯副产的不足，而催化脱氢法基本被淘汰。第 2 章 外文翻译 the production methods of butadiene world for ethanol dehydrogenation was experienced dinitramine, catalytic dehydrogenase, butane catalytic oxidation of dhea, dinitramine dehydrogenation and ethylene byproduct c fractions

16、 separation.1 ethanol dehydrogenation catalysisethanol dehydrogenation production methods of catalytic butadiene 1928 firstly in the former soviet industrialization, this method for magnesium oxide catalyst and silicon product besides butadiene generation. the formation of higher alcohols, aldehydes

17、, ether as many by-products. 1 ton per production butadiene need about three tons of alcohol consumption, this method, the economy has been eliminated.2 catalytic dehydrogenation was dinitraminecatalytic dehydrogenation production yield by butadiene first new jersey mobil oil development company dev

18、elopment. in 1943, the first set of industrialization. then shell and device developed new dow company also produces a catalyst, and also the shel technology and craft, the method of dow industrial production of butadiene made by alcohol as raw materials into petroleum-based. dhea dinitramine, catal

19、ytic materials to mix water with a yield reduced pressure, to improve the hydrocarbon generation and the yield rate of butadiene selective. this method takes the dow process of conversion and selectivity of butadiene dinitramine, respectively for the highest 35% 45 and 90 - 94.3 butane catalytic deh

20、ydrogenasethe source of butane than rich, the price is cheaper dinitramine, besides can come from byproduct c), still can come from outside the distillate of gas and oil gas.butane catalytic dehydrogenation and two-step method has two kinds:houdry one-step production technology development co., houd

21、ry by the united states in 1959, the process of industrialization, the catalyst improvement in the united states and other countries have widely application. houdry butane step by dehydrogenation technology 18% 20% chrome oxide as the catalyst, the impregnation process of alumina without using water

22、 vapor deposition reaction in raw material, the dilution of carbon catalysts. in the process of catalyst regeneration with air, and the overall yield was burned to 62% - 63. philips two-step process by american philips, 1953 industrialization development company, this method for butane conversion fo

23、r 50% of total yield 30%, 60%. in addition, the former soviet union in 1960-1963 developed the two-step process similar to philips two-step process. due to long. complex operation, its application is not one-step widely.4 dinitramine oxidation method of dheadue to the influence of hydrogen reaction

24、rate is not high. one, in order to make the balance to be the direction of butadiene, producing oxygen reacts to the hydrogen, so it can greatly improve the yield rate and generate butadiene selectivity. this process by american petrotex company in 1965 first. then many industrialized factories will

25、 instead of the catalytic oxidation of dhea dhea butadiene production. oxidation rate of dhea production butadiene one-way 70% selectivity for 80 - 92 percent. our successful development in the 1960s dinitramine oxidation production technology, butadiene dhea becomes the main method of butadiene in

26、production.5.from ethylene plant in c isolated butadiene fractionspetroleum hydrocarbons steam cracking is the production of ethylene, propylene, butadiene, etc, and the important method in the separation of ethylene and propylene and separated from cracking c fractions., which contains a lot of but

27、adiene, is the main raw material, production of butadiene by c distillate is currently producing butadiene separation method of butadiene and the vast majority of the world. the product is with a butadiene method of production. due to c in distillate close with the boiling point of butadiene extract

28、ion distillation can be separated. by using different solvents under different methods: furfural, acetonitrile method, dmf, methyl ethyl amide, n. a methyl pyrrole method, etc. widely used in industry is acetonitrile method, dmf and n a methyl pyrrole method.5.1 acetonitrile methodthe earliest shell

29、 company developed by the united states in 1956 and industrial production. it is to cut 10% acetonitrile solvent (ac, the extraction, braising, compression, high pressure, low desorption desorption and solvent recovery process units. 1977 shel company in renovation of the condenser and increased, an

30、d water tower and low voltage braising desorption gas combined compression. about 8% by condensation water tower to wash the solvent distillation column gas phase returns, raw materials from the c c hydrocarbon gases. the rest of hydrocarbon to high tower. another part as desorption transformation r

31、eboiler gas extraction distillation tower bottom to provide heat. eliminating a transformation reboiler, reduces the steam. rinse about 1% to bottom solvent refined, the solvent recovery system to ensure the quality of circular solvent. guiting high content of raw materials needed by the precision p

32、rocessing, or hydrogenation distillation and extraction of two to get high purity of butadiene. currently, this method in italy and japan jsr process technology sir represented.italy in aqueous 5% sir acn solvent, using 5 tower processes (ammonia washing tower, first extraction distillation and extr

33、action distillation, off the light and heavy) off. in the first extraction distillation before washing tower, add a ammonia removal raw materials used in 0.04% 0.08% (quality percentage of aldehydes ketones). guiting extraction distillation tower from the first 75 pieces tower, to contact effluence

34、lateral-line plate condenser. dropping multiplicity.it tower and condenser bottom bottom, the material combined heat recovery after the raw material for the evaporator. not only can make butadiene yield reached 96% 98 percent also can make butadiene and guiting separation, butadiene and product puri

35、ty can reach above. this technique 99.5% characteristic is simple and solvent extraction column in the next section desorption completed by two first extraction distillation, feeding, favorable renovation thermal coupling technique, is the second extraction distillation column of steam. all contain

36、butadiene without condensation directly into dropping multiplicity.it tower. also will drop off heavy tower from the middle part of the fluid flow out on the tray, sent to the second extraction distillation tower, such as fluid backflow second extraction distillation column condenser, this section d

37、oes not need to add to the heat off all the tower, heavy bottom were coupled heat load capacity about 40% lower before, so as to achieve further energy-saving. in 1988, the transformation mainly resolves the problem of heat recovery system. in tower and light towers will install intermediate condens

38、er tower from incoming plate and two nearby series, so can reduce the load, and will not affect the operation conditions. will be divided into two sections, the tower under operating pressure increase. the tower temperature rises, that can be recycled to the middle of condenser high heat. in additio

39、n, the solvent recovery of waste heat bottom tower, which can be used to feed the tower, plus the preheater pipe guiting produced from lateral-line analytical tower is recyclable heat, so this technology part in the same process is the lowest energy consumption by acn method is characteristic of but

40、adiene production of low boiling point: (1), extraction, stripping operation low temperature, easy to prevent butadiene since together, 2 stripper can operate under high pressure gas compressors, saves the butadiene, reduce investment, 3 low viscosity, plates, high efficiency, actual plates, 4 toxic

41、ity, under operating conditions of carbon steel corrosion, 5 and positive butane; butadiene butadiene dimer etc formed azeotrope, solvent refined process is complicated, the high cost of operation, fourthly, high steam pressure with exhaust solvent loses much. 7 recovered solvents washing tower for

42、more, relatively long flow.5.2 dmfdmf method (dmf) and gpb method, by japanese creon company in 1965 and industrial production, a set of 4.5 million tons/year production equipment. the production process, including four processesthe first extraction distillation process, the second extraction distil

43、lation process, distillation process and the solvent recovery process. who first lifo vaporization raw c extraction solvent distillation tower. the upper joined by dmf. the solubility of small, dinitramine, c, butane butadiene makes the relative volatility increases, and from the tower, and guiting

44、butadiene, etc and solvent is derived from the bottom, enter first desorption tower was completely, cooling and desorption by screw compressor compression lifo extraction distillation separation of the second person to further. do not contain c components from the bottom of the solvent extraction te

45、mperature as desorption extractive distillation, distillation, evaporation process such as heat source, quantity of heat recovery after recycling. guiting, propylene and sulfide, carbonyl compounds these harmful impurities in the solubility of solvent, in order to prevent the vinyl acetylene explosi

46、on, and further, the second of recovered solvents butadiene extraction from the bottom to the rich solvents recovery tower, butadiene succinic tower for thickacrylic. recovery tower top fractions of a second and a few impurity butadiene extraction tower before the return, tower kettle including comp

47、ressor population guiting solvent to second from the tower, desorption tower top gives vinyl acetylene, diluted used for fuel, boiler, circular back extraction solvent distillation. the two butadiene extraction distillation crude distillation remove impurities by ordinary. the larger than butadiene

48、volatility, moisture, c, the tower in light and small volatility of butadiene ratio, yield a residual 2-1 in the production of butadiene, c and process of the small butadiene in heavy tower. the bottom dropping multiplicity.it tower above can be obtained in the purity of polymer butadiene 99.5% leve

49、l.the method is characteristic of dmf: (1) the adaptability of raw materials, c butadiene content within the scope of 15-60 can produce qualified products; butadiene 2 large production capacity, low cost, mature technology, annall good energy saving effect, good products, by-products recovery reache

50、s as high as 97%, because of the butadiene dmf) 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

51、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 d

52、ouble olefins and guiting polymerization, no water circumstance of), but in non-corrosive steel under the existing water can decompose generate formate and too, so there must be the corrosive.5.3 n a methyl pyrrole methodn a methyl pyrrole method (nmp) by basf company in germany, and the successful

53、development of industrial production in 1968. built a set of 7.5 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 containin

54、g 8% of n a methyl pyrrole extraction column by entering, butadiene and easily dissolved components 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 w

55、ere 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 composition 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