丁二烯的精馏工艺设计
丁二烯萃取精馏工艺设计
丁二烯萃取精馏工艺设计丁二烯是一种重要的基础化学品,广泛应用于合成合成橡胶、塑料、树脂和油墨等领域。
丁二烯的生产通常采用烷基锂催化剂聚合反应,生成丁二烯和其他杂质。
为了获得高纯度的丁二烯,需要进行精馏分离。
丁二烯萃取精馏是目前广泛采用的一种分离技术,具有操作简便、分离效率高、产品纯度高等优点。
丁二烯萃取精馏工艺的设计涉及到多个关键参数,如萃取剂种类、萃取剂用量、精馏塔塔板数目、进料温度、进料流量等。
下面将从这些方面介绍丁二烯萃取精馏工艺的设计。
1. 萃取剂种类萃取剂是丁二烯萃取精馏中的关键因素之一。
常用的萃取剂有苯、甲苯、二甲苯、正庚烷等。
不同的萃取剂对丁二烯的分离效果有所不同。
例如,苯的选择性较高,但易与丁二烯发生加成反应,形成高沸点产物,影响精馏效果。
因此,在选择萃取剂时应综合考虑其分离效果和化学性质,并选择合适的物料组合。
2. 萃取剂用量萃取剂用量是影响丁二烯萃取精馏效果的另一个重要因素。
一般而言,萃取剂用量越大,分离效果越好,但同时也会增加成本。
在确定萃取剂用量时,应综合考虑经济性和工艺效果,选择合适的用量。
3. 精馏塔塔板数目精馏塔塔板数目对丁二烯萃取精馏的分离效果有着极大的影响。
塔板数目越多,精馏分离效果越好,但同时也会增加设备复杂度和成本。
在选择塔板数目时,应根据实际情况,综合考虑分离效果和成本,选择适当的塔板数目。
4. 进料温度和进料流量进料温度和进料流量是丁二烯萃取精馏中比较重要的参数。
进料温度过高会导致产物分解,影响精馏效果;进料流量过大会降低分离效率。
在确定进料温度和进料流量时,应综合考虑分离效果和工艺经济性,选择合适的操作条件。
丁二烯萃取精馏工艺的设计需要综合考虑多个参数,包括萃取剂种类、萃取剂用量、精馏塔塔板数目、进料温度和进料流量等。
在设计工艺时,应根据实际情况,综合考虑分离效果和成本,选择合适的操作条件,以获得高效、经济、稳定的生产工艺。
DMF丁二烯萃取精馏工艺流程仿真及分析
Abstract: A lar ge am ount o f dat a in diff er ent increasing pr oduct ion phases of a cert ain pet rochemical plant w ere co llect ed. T he first ex t ract ive distillat e device of but adiene w as simulat ed based on ASPEN PL US sof t w ar e, paramet er s o f t ow er pressur e, solvent ratio, ref lux rat io w er e opt imized and analy zed. T he result s show that t he optim um solvent ratio is 8. 0~ 8. 2, and keeping t he separat e ef f iciency o f t he pro duct ion process unchang ed, t o reduce t he reflux r at io can increase processing abilit y of t he dev ice by 20% ~ 30% . Key words: DM F( Drug Master File) method; butadiene ext ract ion dist illation; pro cess; simulation
丁二烯萃取精馏塔的工艺分析
丁二烯萃取精馏塔的工艺分析摘要:丁二烯是一种重要的有机化工原料,在合成橡胶、丁二醇等有机化学产品的生产中具有较高的应用频率。
伴随我国乙烯工业的高速发展,裂解中产生的C4馏分有所增加,是提高炼化企业资源运用率的关键,可在C4分离或合成的作用下,通过萃取精馏塔工艺的使用,完成丁二烯产品生产的任务。
鉴于此,本文围绕丁二烯萃取精馏工艺技术,简述了对塔设备选择的两个方面,以C4分离法配合乙腈作为萃取溶剂为例,详细分析了丁二烯萃取精馏塔的主要生产方法和具体工艺流程。
关键词:丁二烯;萃取精馏塔;工艺;分析;设备选择引言:工业上当前主要使用乙腈、甲基吡咯烷酮等作为萃取剂,经过萃取精馏工艺,将乙烯裂解设备中的副产物进行分离处理后,便可得到纯度较高的丁二烯。
丁二烯萃取精馏塔是C4抽提设备中塔板数量最多、塔径最大的重要设备,具有影响因素多、投资比重大等特点,因此,需要有关技术人员加强对丁二烯萃取精馏塔工艺的分析和优化,按照详细工艺流程和要求,获得纯度合格的丁二烯产品。
1丁二烯萃取精馏塔的设备选择1.1塔设备选择的要求板式塔与填料塔均为丁二烯萃取精馏工艺中的关键设备,分别担任了不同生产任务中的精馏、吸收等操作,具有优势互补的作用。
由于分离性能较强,操作稳定性优良,逐渐成为主要的生产分离设备。
在选择塔设备时,需要满足于丁二烯萃取精馏的各项工艺要求,具备较高的分离能效;生产能力优良,拥有充足的操作弹性,且操作简单、加工方便、可靠性强,能够达成自动化的目标;塔设备的压降较小,还要具有前期投入较少、制造便捷的优势。
1.2板式塔类型和性能对比按照类型上的差异,板式塔设备拥有不尽相同的结构形式,其中的穿流式塔的板式结构包括筛孔式、栅板式,溢流式塔的塔板则包括十字架形浮阀、F形浮阀、舌形板、条形泡罩、圆形泡罩等。
伴随板式塔塔压降的下降,压差值存在成倍变化的可能性,对于塔设备的操作压力影响更小,除了真空塔以外,造成的相对挥发度变化较小。
丁二烯抽提终版工艺流程简介
第一萃取蒸馏部分在DMF存在的情况下,凡与丁二烯相比其相对挥发度高于1.0的组分,都在这部分除去。
这部分设备有:原料汽化罐,第一萃取蒸馏塔(分为两个塔,共有238块塔板)以及装有14层塔板的第一汽提塔。
C4原料从乙烯装置A单元进入原料储罐后用泵送来经流量控制进入原料汽化罐。
原料汽化罐的热源由第一、第二汽提塔底的热溶剂提供。
汽化的C4原料送至第一萃取蒸馏塔的中部(进料板104层,114层,125层)。
DMF溶剂经流量控制进入T -1101A顶部第230层塔板上,溶剂进料温度约40℃,蒸汽压约9毫米汞柱。
塔顶8层塔板用于丁烷丁烯馏分中完全脱除溶剂的精馏段。
塔的操作压力约为0.38MPa(表压),塔顶操作温度约为43.5℃。
根据进料组成的变化,适当调节溶剂进料量和回流量,以控制丁二烯的损失量和塔釜液的组成,丁烷丁烯馏出液的1,3-丁二烯含量保持在0.3%(重量)以下。
塔顶丁烷丁烯抽余液直接送至MTBE装置或A单元罐区。
萃取蒸馏必要的回流经流量调节,经过上述8层塔板的精馏段,向下流至溶剂进料塔板。
顺2-丁烯是比1,3-丁二烯难溶解的一种组分,在第一萃取蒸馏塔中它是最难于分离出来的。
按GPB工艺,通常第一萃取蒸馏塔底的顺2-丁烯含量约为总烃的2.5%,而反2-丁烯含量约为总烃的0.05%。
顺2-丁烯在第二分馏塔(T-1302)随塔底物料脱除,但反2-丁烯不易在直接蒸馏部分脱除。
因此,第一萃取蒸馏塔的分离效果对最终丁二烯产品的纯度有影响。
在GPB工艺中提纯丁二烯的经济方法是在第一萃取蒸馏部分脱除全部反2-丁烯,随之脱除部分顺2-丁烯。
而在第二分馏塔脱除剩余的顺2-丁烯。
在第一萃取蒸馏塔(T-1101B)的C-3层塔板上,含烃(主要是含丁二烯和易溶组分)的溶剂被预热到86℃。
这些溶剂先通过第一萃取蒸馏塔的第一、第二溶剂再沸器,被来自汽提塔底的热溶剂加热到120℃。
然后,在第一萃取塔蒸汽再沸器中把它进一步加热到大约130℃。
毕业设计(论文)4万吨年1,3丁二烯生产装置第一萃取精馏塔工艺设计
1 绪论 (1)1.1设计依据 (1)1.2 设计的目的及意义 (1)1.3 1,3-丁二烯的物化性质 (1)1.4 原辅材料介绍 (2)1.4.1 原料规格 (2)1.4.2 二甲基甲酰胺(DMF)性质 (2)2 1,3-丁二烯的生产 (2)2.1 1,3-丁二烯的生产方法 (2)2.2 生产原理 (3)2.3 工艺技术路线 (3)3 主要设备的工艺设计及计算 (4)3.1 基础数据 (4)3.1.1 C4组分 (4)3.1.2 相对挥发度α的计算 (5)3.2 塔设备的工艺设计及计算 (8)3.2.1第一萃取精馏塔的计算 (8)3.3 3.3塔板主要工艺尺寸的计算度 (12)3.3.1 溢流装置的计算 (12)3.3.2 溢流堰高度wh............................... 错误!未定义书签。
3.3.3 弓形降液管宽度Wd和截面积fA................ 错误!未定义书签。
3.3.4 降液管底隙高度oh........................... 错误!未定义书签。
3.4 塔板布置 (13)3.4.1 塔板的分布 (13)3.4.2 边缘区宽度的确定 (13)3.4.3 开孔区面积计算 (14)3.5 流体阻力计算 (14)3.5.1 干板阻力的计算 (14)3.5.2 气体通过液层阻力计算 (14)3.5.3 液体表面张力的阻力hσ计算 (14)3.5.4 漏液 (15)3.5.5 液泛 (15)3.6 塔板负荷性能图 (15)3.6.1 漏液线 (15)漏液线由漏液点气速来标绘出对应的 VS -LS. (15)3.6.2 液相负荷下限线 (15)3.6.3 液相负荷上限线 (16)3.6.4 液泛线 (16)塔体设计总表 (17)参考文献 (19)致谢 (20)1 绪论1.1设计依据(1)年产1,3-丁二烯:5.0万吨/年(2)原料来源:由乙烯裂解送来的C4混合烃(3)年操作时间:7800小时(4)本装置能在设计能力为50%的负荷下运行。
丁二烯生产技术
丁二烯生产技术进展2011-08-25丁二烯通常指1,3-丁二烯,是一种非常重要的石油化工原料,可以合成顺丁橡胶(BR)、丁苯橡胶(SBR)、丁腈橡胶(NBR)、苯乙烯-丁二烯-苯乙烯弹性体(SBS)、氯丁橡胶(CR)、丙烯腈-丁二烯-苯乙烯(ABS)树脂等多种产品,还可用于生产己二腈、己二胺、尼龙66、1,4-丁二醇等有机化工产品,用途十分广泛。
丁二烯的生产方法主要有乙烯裂解副产C4抽提法和C4烷烃或烯烃脱氢法,其中,乙烯裂解副产丁二烯约占全球丁二烯总生产能力的98%,是丁二烯的主要生产工艺。
从乙烯裂解装置副产混合C4抽提丁二烯工艺使用不同的溶剂来区分,主要有以日本合成橡胶(JSR)公司为代表的乙腈(ACN)工艺、日本瑞翁(Zeon)公司的二甲基甲酰胺(DMF)工艺和德国巴斯夫(BASF)公司的N-甲基吡咯烷酮(NMP)工艺三种流程。
自20世纪50年代丁二烯抽提工艺实现工业化以来,各大技术专利商均一直致力于技术改进,并在装置能耗物耗、运行稳定性和安全性等方面取得突破性进展,丁二烯抽提工艺也日趋成熟。
近年来,丁二烯技术研究主要集中在新型设备应用、萃取精馏系统的局部改进、反应精馏组合工艺研究、新型阻聚剂系统开发和丁二烯生产新技术的研究等方面。
1 萃取精馏工艺的改进1.1 隔壁精馏塔丁二烯第一萃取精馏工艺巴斯夫公司对传统的丁二烯抽提工艺进行了改进,第一萃取精馏塔采用隔壁精馏塔,一萃部分采用隔壁塔与萃取洗涤塔、溶剂脱气塔组合的新工艺,萃取溶剂采用含水的NMP溶液,分离可得到粗1,3-丁二烯。
C馏分换热后进入隔壁塔第一分区的中部,来自萃取洗涤塔的底部物流循环进入4第一分区的上部,来自溶剂脱气塔的一股溶剂进入第二分区的上部,第二分区的炔烃化合物塔顶抽出粗1,3-丁二烯产品,从隔壁塔的下部共用塔区域抽出含C4的溶剂,这股物流进入溶剂脱气塔进行溶剂再生,脱气塔塔釜物流循环。
来自隔壁精馏塔第一分区的顶部物流加入到萃取洗涤塔的下部,通过在萃取洗涤塔的上部区域加入一股溶剂进行逆流萃取,从萃取洗涤塔的顶部抽出抽余液。
丁二烯精馏外文翻译
吉林化工学院环境与生物工程学院课程设计外文翻译丁二烯的精馏工艺设计butadiene distilldtion process design吉林化工学院Jilin Institute of Chemical TechnologyProcess for the separation of butadiene by plural stage extractive distillationAbstract:Butadiene is recovered from a hydrocarbon fraction containing it together with butenes and acetylene hydrocarbons by introducing said fraction into a first extractive distillation column, feeding aqueous acetonitrile into said column above the introduction point of said fraction and extracting a vapor stream containing butadiene below said introduction point; feeding said vapor stream into a second extractive distillation column, feeding aqueous acetonitrile above the introduction point of said vapor stream and recovering a vapor stream consisting essentially of butadiene at the top of said second column; and rectifying this last vapor stream to recover pure butadiene.Keywords: butadiene distillation process designProcess of production1. A process for the separation and recovery of 1,3-butadiene from a hydrocarbon mixture containing it, which comprises: introducing into an extractive distillation column having at least 150 plates, operating at a pressure of 3.5-5.5a tmospheres and at a bottom temperature of 110°-140° C. and head temperature of 30°-50° C., a stream of vaporized hydrocarbon fraction containing butadiene together with butenes and acetylene hydrocarbons at a point intermediate between the head and the bottom and feeding aqueous acetonitrile at one or more points of the columm between the head and the point of introduction of the hydrocarbon fraction; recovering at the head of the column a stream consisting essentially of butenes, recovering at the bottom aqueous acetonitrile and removing at an intermediate point, situated lower than that of the introduction of the hydrocarbon fraction, a vapor stream containing butadiene;feeding into a second extractive distillation column, having at least 80 plates and operated at temperatures and pressures in the range of those of the first column, the vapor stream containing butadiene extracted from the said first extractivedistillation column, at a point intermediate between the head and the bottom, feeding aqueous acetonitrile at one or more points situated between the head of the second extractivedistillation column and the point of introduction of the vapor stream containing butadiene; recovering at the head of the second extractive distillation column a stream consisting essentially of butadiene, at the bottom aqueous acetonitrile, while removing a vapor stream consisting essentially of acetylene hydrocarbons at a point of the second extractive distillation column located between the bottom and the feed point of the vapor stream containing butadiene; subjecting the head product of the second extractive distillation column to rectification in a third distillation column to remove the last traces of products with a lower boiling point than butadiene at the head of said third distillation column and of those with a higher boiling point than butadiene as a bottoms product of said third distillation column.2. The process of claim 1, in which a liquid side stream is removed from the first extractive distillation column from a point situated below the removal point of the vapor streamcontaining butadiene, this liquid stream is heated at a temperature up to 90°-100° C. and this heated liquid stream is reintroduced into the first extractive distillation column at a point corresponding to the plate immediately below the one where said liquid side stream is drawn.3. The process of claim 1, in which the hydrocarbon fraction containing butadiene is subjected to a treatment with aqueous ammonia, before being fed into the first extractive distillation column, in order to bring its content in carbonyl compounds below 50 ppm.4. The process of claim 1, in which said aqueous acetonitrile fed into the first and second extractive distillation columns has a water content of from 3 to 10% by weight.5. The process of claim 1, in which the first extractive distillation column contains from 150 to 220 plates, the hydrocarbon fraction containing butadiene is fed in at a point of the first extractive distillation column between the 45th and 65th plate downwards from the head, the aqueous acetonitrile is fed in at two points, the first between the 6thand 7th plate, the second between the 40th and 60th plate downwards from the head, and the gaseous stream containing butadiene is drawn from a point of the column situated between the 100th and the 170th plate downwards from the head.6. The process of claim 1, in which the weight ratio of aqueous acetonitrile fed to the first extractive column to the hydrocarbon fraction containing butadiene fed to said first extractive distillation column is from 7:1 to 13:1.7. The process of claim 1, in which the second extractive distillation column contains from 80 to 105 plates, the gaseous stream containing butadiene extracted from the first extractive distillation column is fed in at a point situated between the 40th and 60th plate downwards from the head, the aqueous acetonitrile is fed in at a point situated between the 7th and 8th plate downwards from the head and the gaseous stream containing acetylene hydrocarbons is drawn from a point situated between the 65th and the 85th plate downwards from the head.8. The process of claim 1 in which the weight ratio of theaqueous acetonitrile fed to the second extractive distillation column to the vapor stream containing butadiene fed to said second extractive distillation column is from 3:1 to 6:1.9. The process of claim 1, in which the head product of the second extractive distillation column is distilled in a first distillation column containing 40-50 plates, with removal, at the head, of the traces of products having a lower boiling point than butadiene, and the resulting bottom product is then distilled in a second distillation column containing 40-55 plates with recovery of the butadiene at the top of said second distillation column and removal of the traces of products having a higher boiling point than butadiene as bottom product.10. The process of claim 5, in which the hydrocarbon fraction containing butadiene is fed into the first extractive distillation column at a point of the column between the 53rd and the 55th plate and the vapor stream containing butadiene is drawn from said first extractive distillation column at the level of the 150th plate.11. The process of claim 1, in which the second extractivedistillation column contains from 95 to 100 plates.12.The process of claim 1, in which the vapor stream containing acetylene hydrocarbons is drawn from the second extractive distillation column at the level of the 75th plate from the top of the column.13. The process of claim 1, wherein said aqueous acetonitrile is fed at one point situated between the head of the second extractive distillation column and the point of introduction of the vapor stream containing butadiene.Description:The present invention relates to the separation of butadiene (1,3- butadiene) of high purity, from mixtures which contain it together with other hydrocarbons.The butadiene constitutes a much valued product which finds many applications, particularly in the preparation of synthetic rubber, such as the copolymers of butadiene and styrene or acrylonitrile, and more recently polybutadiene.The source for butadiene normally used in industry is a hydrocarbon mixture obtained by pyrolysis of petroleum cuts. In fact, it is known that in the production of ethylene and/or propylene by pyrolysis of liquefied petroleum gas or of naphtha, one obtains, among the secondary products, a fraction (C 4 fraction) rich in butadiene and also containing butenes (butene-1, trans-butene-2 and cis-butene-2) and acetylenes (methylacetylene, ethylacetylene and vinylacetylene).This C 4 fraction cannot be fractionated into its individual constituents by means of the normal distillation treatments and, therefore, one resorts to extractive distillation in the presence of special solvents, in order to separate a butadiene having the requisite degree of purity.In fact, the impurities, especially the acetylenes, have a deleterious effect on the polymerization of butadiene.The solvents suitable for extractive distillation possess polar characteristics and are normally selected among: acetonitrile, acetone, furfural, dimethylformamide, dioxan, phenol, N-methyl-pyrrolidone and dimethylacetamide.Operating in accordance with the prior art, it is not easy to obtain high yields of butadiene, especially because of the difficulty in satisfactorily separating this compound from the acetylene hydrocarbons. There are also risks of polymerization of the butadiene, and such a phenomenon, apart from a decrease in the yield, can give rise to deposits and obstructions in the apparatus.Amongst the various causes for this, the temperature is of special importance because it favours the formation of polymers and therefore it is essential, although then very difficult, to keep the temperature levels in the column at sufficiently low values, inasmuch as the simple use of butadiene polymerisation inhibitors does not produce satisfactory results.The crude butadiene which is recovered after the extractive distillation treatment is, as known, subjected to rectification for the purpose of removing the residual impurities.When one operates by means of the conventional methods, the quantity and the nature of these impurities is generally such as to make the rectification treatment very expensive.In conclusion, in order to obtain sufficiently pure butadiene, with the known methods, one operates with expensive processes which require a high energy consumption and complex equipments of considerable bulk.According to the present invention one eliminates the disadvantages of the previously known methods, or at least one greatly reduces them, recovering the butadiene from the C 4 fractions, by the technique of extractive distillation with aqueous acetonitrile as a solvent and operating within a rigorous set of conditions.The present invention provides a process for the separation and recovery of butadiene (1,3- butadiene) from a hydrocarbon mixture containing it, which comprises:introducing into an extractive distillation column having at least 150 plates, operating at a pressure of 3.5-5.5 atmospheres and at a bottom temperature of 110-140° C. and head temperature of 30-50° C., a stream of vaporized hydrocarbon fraction containing butadiene together with butenes and acetylene hydrocarbons at a point intermediate between the head and the bottom and feeding aqueous acetonitrile at one or more points of the column between the head and the point ofintroduction of the hydrocarbon fraction; recovering at the head of the column a stream consisting essentially of butenes, recovering at the bottom aqueous acetonitrile and extracting at an intermediate point, situated lower than that of the introduction of the hydrocarbon stream, a vapor stream containing the butadiene;feeding into a second extractive distillation column, having at least 80 plates and operated at temperatures and pressures in the range of those of the first column, the vapor stream containing butadiene coming from the said first column at a point intermediate between the head and the bottom, feeding aqueous acetonitrile at one or more points situated between the head of the column and the point of introduction of the vapor stream containing butadiene; recovering at the head of the column a stream consisting essentially of butadiene, at the bottom aqueous acetonitrile, while extracting a vapor stream consisting essentially of acetylenes at a point of the column located between the bottom and the feed point of the vapor stream containing butadiene;subjecting the head product of the second extractive distillation column to rectification to separate the lasttraces of products with a lower boiling point than butadiene and of those with a higher boiling point.According to a preferred embodiment of the present invention one draws from the first extractive distillation column a flow of liquid from a point situated below the tapping point of the vapor flow containing the butadiene. The said liquid flow is heated at a temperature of up to 90-100° C. and re-introduced into the column at a point corresponding to the plate immediately below the one where the liquid was drawn. Operating according to the process of the invention, one recovers butadiene with a yield of the order of 96-98% relative to that contained in the hydrocarbon fraction subjected to the treatment. This butadiene is typically of a purity in excess of 99.5%.Summaryprofound understanding of the whole rectification works, but also for its better understanding of the production process, and the current domestic and international applications in this area have also been a more profound understanding, I believe it will be in my future study and work a great help.丁二烯通过萃取精馏的工艺分离摘要:丁二烯是从含有丁烯和乙炔碳氢化合物的油气部分回收而来,开头部分为第一萃取精馏柱,乙腈水溶液到上述精馏塔用分数表示,提取部分汽流混合物都含有一定百分数的丁二烯,乙腈水溶液蒸气流进入第二萃取精馏塔,上述乙腈蒸气流和恢复汽流组成精馏塔塔顶蒸气流,最后经第二精馏塔后,蒸气流恢复纯丁二烯。
丁二烯抽提工艺方法的比较与选择
丁二烯抽提工艺方法的比较与选择摘要丁二烯的加工利用水平和化工利用技术的发展对国家合成橡胶工业生产的发展有着重要影响。
丁二烯的生产可分为乙腈法、二甲基甲酰胺法和N甲基吡咯烷酮法三种。
不论是哪种溶剂,抽提工艺一般都采用两段萃取精馏,即先用溶剂萃取丁二烯及炔烃,把它们与丁烷,丁烯馏分分开,再用同一溶剂在炔烃萃取精馏塔中萃取掉炔烃,得到丁二烯馏分,丁二烯馏分脱除轻重组分后,便得到丁二烯。
三种方法都有各自的特点,在选择生产丁二烯的方法时,要详细比较各自的优缺点,选择出最适合的工艺方法。
关键词:丁二烯工艺;溶剂;抽提1丁二烯的简介丁二烯,通常是指1,3-丁二烯,又称乙烯基乙烯,分子式C4H6,无色气体。
熔点108.9℃,沸点4.41℃,微溶于水和醇,易溶于苯、甲苯、氯仿、等有机溶剂。
丁二烯在常温常压下为无色而略带大蒜味的气体,易液化,易燃,聚合。
丁二烯具有麻醉和刺激作用,可能引起遗传缺陷,可致癌。
丁二烯是碳四馏分中最重要的组分,是石油化工的基本原料之一,在石油化工烯烃原料中的地位仅次于乙烯和丙烯, 世界丁二烯主要用于合成橡胶以及ABS树脂等。
2丁二烯的生产方法我国丁二烯的生产经历了酒精接触分解、丁烯或丁烷氧化脱氢和蒸气裂解制乙烯联产C4抽提分离三个发展阶段。
C4抽提分离这种方法价格低廉,经济上占优势,是目前世界上丁二烯的主要来源。
只有少数一些丁烷、丁烯资源丰富的国家采用脱氢法。
目前我国正在运行的丁二烯生产装置,绝大多数都是随着乙烯工业的发展而逐步配套建设起来的[1]。
2.1乙腈法乙腈法(ACN法)乙腈法以含水10%左右的乙腈为溶剂,由两段萃取精馏、两段普通精馏、和溶剂回收等工艺单元组成。
原料裂解碳四第一萃取精馏塔,与塔顶来的乙腈接触。
丁烷、丁烯、反丁烯-2等从塔顶馏出,塔底含丁二烯和重组分的乙腈溶液由釜液泵送至汽提塔将烃类组分从乙腈溶液中汽提出来。
汽提塔中部炔烃浓度最高,侧线采出送入炔烃闪蒸塔汽提塔釜液由汽提塔釜液泵打出,作为循环溶剂。
毕业设计与论文(年产11.5万吨丁二烯的精馏工艺设计)
丁二烯生产流程
编号:No.13d jj课题:碳4抽提工艺流程授课内容:●典型碳4抽提工艺流程●碳4抽提过程操作方法知识目标:●掌握典型碳4抽提工艺原则流程●了解碳4抽提过程操作方法能力目标:●分析和判断影响萃取精馏过程主要因素●分析和判断精馏萃取过程操作异常现象及处理方法思考与练习:●碳4乙睛抽提工艺构成●溶剂对抽提过程有何影响?●碳4乙睛抽提过程操作有何异常现象?授课班级:授课时间:年月日三、工艺流程1、乙腈法(ACN法)乙腈法是以含水5%~10%的乙腈为溶剂,以萃取精馏的方法分离丁二烯。
我国于1971年5月由兰化公司合成橡胶厂自行开发的乙腈法C4抽提丁二烯装置试车成功。
该装置采用两级萃取精馏的方法,一级是将丁烷、丁烯与丁二烯进行分离,二级是将丁二烯与炔烃进行分离。
其工艺流程见图3—1。
由裂解气分离工序送来的C4馏分首先送进碳三塔(1)碳五塔(2),分别脱除C3馏分和C5馏分,得到精制的C4馏分。
精制后的C4馏分,经预热汽化后进入丁二烯萃取精馏塔(3)。
丁二烯萃取精馏塔分为两段,共l20块塔板,塔顶压力为0.45Mpa,塔顶温度为46℃,塔釜温度114℃.C4馏分由塔中部进入,乙腈由塔顶加入,经萃取精馏分离后,塔顶蒸出的丁烷、丁烯馏分进入丁烷、丁烯水洗塔(7)水洗,塔釜排出的含丁二烯及少量炔烃的乙腈溶液,进入丁二烯蒸出塔(4)。
在塔(4)中塔釜排出的乙腈经冷却后供丁二烯萃取精馏塔循环使用,丁二烯、炔烃从乙腈中蒸出去塔顶,并送进炔烃萃取精馏塔(5)。
经萃取精馏后,塔顶丁二烯送丁二烯水洗塔(8),塔釜排出的乙腈与炔烃一起送入炔烃蒸出塔(6)。
为防止乙烯基乙炔爆炸,炔烃蒸出塔(6)顶的炔烃馏分必须间断地或连续地用丁烷、丁烯馏分进行稀释,使乙烯基乙炔的含量低于30%(摩尔),炔烃蒸出塔釜排出的乙腈返回炔烃蒸出塔循环使用,塔顶排放的炔烃送出用作燃料。
在塔(8)中经水洗脱除丁二烯中微量的乙腈后,塔顶的丁二烯送脱轻组分塔(10)。
丁二烯萃取精馏工艺设计
丁二烯萃取精馏工艺设计毕业设计(论文)题目名称丁二烯萃取精馏工艺设计系部专业班级学生姓名指导教师辅导教师时间目录任务书 (Ⅰ)开题报告 (Ⅱ)指导教师审查意见 (Ⅲ)评阅教师评语 (Ⅳ)答辩会议记录 (Ⅴ)中文摘要 (Ⅵ)外文摘要 (Ⅶ)1.前言 (1)1.1性质及用途 (1)1.2国内/外生产概况 (1)1.3生产方法 (4)2.生产工艺 (11)2.1生产原理 (11)2.2工艺流程 (11)2.3工艺流程图 (15)3.基础计算 (17)3.1物料衡算 (17)3.2热量衡算 (31)4.设备计算 (36)4.1基础数据计算 (36)4.2汽液负荷量 (37)4.3脱重塔计算 (38)4.4脱轻塔计算 (46)5.结论 (55)参考文献 (56)致谢 (59)附录一:设备图 (61)附录二:毕业设计查重报告 (62)文档仅供参考**********程技术学院毕业设计(论文)任务书分院专业化学工程与工艺班级化工61201 学生姓名指导教师/职称1.毕业设计(论文)题目:丁二烯萃取精馏工艺设计2.毕业设计(论文)起止时间: 10月15日~年6月1日3.毕业设计(论文)所需资料及原始数据(指导教师选定部分)[1]黄春超.年产7万吨丁二烯工艺设计[D].大连理工大学,.5.7.[2]袁霞光.丁二烯生产技术进展[J].当代石油化工,,4:25~29.[3]王嵩智.乙腈萃取精馏分离丁二烯的工艺流程模拟[J].弹性体,1998,1:30~35.[4]王程琳,包宗宏.三种萃取精馏法生产1,3-丁二烯的经济评价[J].当代化工,,43(7),1252~1256.[5]朱淑军.C4馏分丁二烯萃取精馏塔的模拟和分析[J].科技进展,,4:23~28.[6]马沛生,李永红.化工热力学(通用型)第二版[M].化学工业出版社,,1:109~147;159~173.[7]贾绍义,柴诚敬.化工单元操作课程设计[M].天津:天津大文档仅供参考学出版社,.1:108~171.[8]谭天恩,窦梅.化工原理,第四版.北京:化学工业出版社,.1:上下册.4.毕业设计(论文)应完成的主要任务(1)阅读文献和教科书,撰写开题报告;(2)学会物料衡算,能量衡算;(3)掌握设备计算要点以及利用CAD绘制设备图;(4)学会工艺流程图的绘制和工艺流程的描述;(5)撰写毕业论文,准备论文答辩。
丁二烯精馏化工综合设计
摘要本设计为年产4.5万吨丁二烯精制工段的工艺设计,参照了吉化股份公司104厂丁二烯车间的丁二烯精制工艺流程和工艺参数。
本设计对丁二烯精制过程做了详细的阐述。
绘制了工艺流程图、设备平面布置图和主要设备管道布置图。
关键词:丁二烯精馏工艺设计目录摘要 (I)目录 (I)第一篇设计说明书.............................................................................................................. - 1 - 第1章绪论................................................................................................................................ - 1 -1.1 丁二烯的供需现状..................................................................................................... - 1 -1.2 丁二烯的用途............................................................................................................... - 2 - 第2章丁二烯生产技术及其进展.......................................................................................... - 3 -2.1日本JSR工艺............................................................................................................... - 3 -2.2 日本瑞翁公司的DMF法............................................................................................ - 4 -2.3 BASF公司的NMP工艺 .......................................................................................... - 5 -2.4 UOP公司的KLP工艺............................................................................................. - 6 -2.5 丁烯生产丁二烯新技术............................................................................................. - 6 - 第3章工艺路线的确定.......................................................................................................... - 8 -3.1 生产路线..................................................................................................................... - 8 -3.2原料概况........................................................................................................................ - 8 -3.3 原料、辅助物料、成品的主要技术特性................................................................. - 8 -3.3.1原料规格............................................................................................................. - 8 -3.4工艺条件..................................................................................................................... - 9 -3.5 产品质量..................................................................................................................... - 9 -3.5.1产品主要控制指标及执行标准、分析方法..................................................... - 9 -3.6 生产工艺..................................................................................................................... - 9 -3.6.1 萃取精馏系统.................................................................................................. - 9 -3.6.3 三废处理........................................................................................................ - 11 - 结论...................................................................................................................................... - 12 - 参考文献.............................................................................................................................. - 13 - 致谢 ........................................................................................................................................... - 14 -第一篇设计说明书第1章绪论1.1 丁二烯的供需现状近几年,随着中国多套乙烯新建装置的建成投产,为丁二烯的发展提供了大量的裂解C4原料,使得中国丁二烯的生产能力大幅度增加。
年产5万吨丁二烯工艺设计
---------------------------------------------------------------范文最新推荐------------------------------------------------------ 年产5万吨丁二烯工艺设计摘要:本设计内容为年产5万吨丁二烯的工艺设计,本工艺采用萃取精馏的方法,由乙烯装臵从副产的混合C4馏分中分离丁二烯,并由混合C4馏分精馏得到纯度大于99.0%的丁二烯产品。
丁二烯是从含有丁烯和乙炔碳氢化合物的油气部分回收而来,开头部分为第一萃取精馏柱,乙腈水溶液到上述精馏塔用分数表示,提取部分汽流混合物都含有一定百分数的丁二烯,乙腈水溶液蒸气流进入第二萃取精馏塔,上述乙腈蒸气流和恢复汽流组成精馏塔塔顶蒸气流,最后经第二精馏塔后,蒸气流恢复纯丁二烯。
本设计完成了整个工序的物料衡算,同时也对脱重组分塔进行了设备计算,包括热量衡算,露泡点,回流比以及理论板的计算等等,确定了塔高和塔径,并对塔顶冷凝器进行了详细的计算及选型。
绘制了工艺流程图,设备布臵图以及车间布臵图。
9124关键词:丁二烯;萃取;精馏;工艺1 / 26Annual output of 50,000 tons of pyrrolylene butadiene process designAbstract: This design is an annual output of 50,000 tons of butadiene distillation process design, the process method of extractive distillation using ethylene plant by-product isolated C4 butadiene C4 distillate distillates distillation into butadiene purity greater than 99.0% products. Butadiene is from containing maleic and acetylene hydrocarbon oil and gas recovery, beginning as the first extractive distillation column, acetonitrile water solution to the distillation column is expressed as a fraction, butadiene extraction steam mixture contains a certain percentage, aqueous acetonitrile vapor flow into the second extractive distillation column, the steam flow and acetonitrile recovery of steam flow form the top of the distillation column of steam flow, finally after second distillation tower, steam recovery of pure butadiene. The design is completed the entire process of material balance, and from the reorganization of sub-tower to carry out a rigorous calculation of the equipment, including the heat---------------------------------------------------------------范文最新推荐------------------------------------------------------balance, the bubble point, reflux ratio and theoretical plate calculations to determine the tower, the tower diameter. On top of the tower carried out a detailed calculation of condenser selection. Drawn with the process control point plan, equipment layout, and plant layout.4.3.1 求泡点温度234.3.2 计算回流比R最小回流比理论板数245 热量衡算295.1 操作条件295.1.1 塔顶塔釜温度295.1.2 实际板数、实际进料板位臵、板效率305.2 热量衡算313 / 266 塔设备计算346.1 计算气液负荷346.2 下面选脱重组分塔进行计算36 6.2.1 初估塔径D376.2.2 溢流装臵计算396.2.3 浮阀数的计算406.2.4 塔板布臵416.2.5 阻力计算426.2.6 淹塔校核436.2.7 雾沫夹带校正446.2.8 塔板负荷性能图44---------------------------------------------------------------范文最新推荐------------------------------------------------------ 7 附属设备的选型与计算497.1 脱重组分塔塔顶冷凝器497.1.1 计算传热量和对数平均温度差497.1.2 初步选定换热器型号507.2 传热器校核517.3 换热器内动流体的流阻力537.3.1 管程阻力537.3.2 壳程阻力537.4 选泵548 工艺流程图565 / 269 设备布臵图5710 车间布臵图58致谢59附录60参考文献621 产品概述1.1 题目背景和意义1863年,法国化学家从裂解戊酒精中分离出一种以前未知的碳氢化合物,这种碳氢化合物被确定为丁二烯。
丁二烯工艺设计doc资料
丁二烯工艺设计河北工业大学成人高等教育毕业设计说明书(论文)姓名:张天星学号:教学管理单位:河北工业大学继续教育学院大港教学站专业:化学工程与工艺题目:丁二烯工艺设计指导者:沈坚评阅者:2015年 9 月 20 日毕业设计(论文)摘要目录1 引言 (1)2 工艺路线 (1)2.1 生产的基本原理 (1)2. 2 工艺路线的对比与选择 (2)2. 3 DMF法碳四抽提丁二烯装置的特点 (3)2. 4 物料衡算 (4)2. 5 装置工艺流程图 (5)2. 6 工艺流程说明 (5)2.6.1 第一萃取精馏部分 (5)2.6.2 第二萃取精馏部分 (8)2.6.3 丁二烯净化部分 (9)2.6.4 溶剂净化部分 (10)2. 7 工艺控制 (11)2.7.1 原料质量变化对产品的影响及调节方法 (12)2.7.2 主要工艺条件的变化对产品质量的影响 (13)结论 (16)参考文献 (17)致谢 (18)1 引言丁二烯来源:从油田气、炼厂气和烃类裂解制乙烯的副产品中都可获得碳四馏分。
碳四系列的基本有机化工产品主要有丁二烯、顺丁烯二酸酐、聚丁烯、二异丁烯、仲丁醇、甲乙酮等,它们是有机化学工业的重要原料。
无论是裂解气深冷分离得到的碳四馏分,还是经丁烯氧化脱氢得到的粗丁二烯,均是以碳四各组分为主的烃类混合物,主要含有丁烷、正丁烯、异丁烯、丁二烯,它们都是重要的有机化工原料[1,2]。
C4的分离与C2、C3馏分相比,其最大的特点是各组分之间的相对挥发度很小,使分离变得更加困难,采用普通精馏方法在通常条件下将其分离是不可能的。
为此工业生产中常用在碳四馏分中加入一种溶剂进行萃取的特殊精馏来实现对C4馏分的分离[3-5]。
2 工艺路线2.1 生产的基本原理由于碳四原料中大部分组分与丁二烯-1,3之间的沸点较为接近,而且相互之间有共沸物产生,这样采用一般的精馏方法很难进行分离开,所以为了得到目标产品(丁二烯)就必须采用特殊分离方法——萃取精馏。
分壁式精馏塔精制丁二烯流程模拟
的节能原 因。结果表 明, 当主塔 理论板数 1 0 5 ,预分 离塔 理论 板数 5 6 ,进入预分 离塔 气相 流量 1 0 2 0 k mo l / h ,液 相 流量 8 9 0 k mo 1 / h ,回流 比 7 8 0 0时,DWC分 离效 果最好 ,丁二烯质量分数可 达 9 9 . 7 %,这 为 D WC精 制丁二 烯 工艺的工业化提供 了理论依据 。由于 DWC有效减 少了精馏 过程 中的返混效应 ,提 高了能量 利用率,使 其冷凝 器 可节能 2 9 . 3 6 %,再 沸器可节能 2 9 . 1 9 %,存在 明显 的节能优势 。 关键词 :模拟 ;分壁 式精馏塔 ;丁二烯 ;蒸馏 ;优化
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化工与材料工程学院毕业设计年产1.6万吨丁二烯的精馏工艺设计学生学号学生姓名专业班级指导教师金朝晖副教授联合指导教师高华晶副教授完成日期2011-8-29化工学院Chemical Technology摘要丁二烯是一种重要的石油化工基础有机原料和合成橡胶单体,是C4馏分中最重要的组分之一,在石油化工烯烃原料中的地位仅次于乙烯和丙烯。
由于其分子中含有共轭二烯,可以发生取代、加成、环化和聚合等反应,使得其在合成橡胶和有机合成等方面具有广泛的用途,可以合成顺丁橡胶(BR)、丁苯橡胶(SBR)、丁腈橡胶、苯乙烯-丁二烯-苯乙烯弹性体(SBS)、丙烯腈-丁二烯-苯乙烯(ABS)树脂等多种橡胶产品,此外还可用于生产己二腈、己二胺、尼龙66、1,4-丁二醇等有机化工产品以及用作粘接剂、汽油添加剂等,用途十分广泛。
目前,世界丁二烯的来源主要有两种,一种是从炼油厂C4馏分脱氢得到,该方法目前只在一些丁烷、丁烯资源丰富的少数几个国家采用。
另外一种是从乙烯裂解装置副产的混合C4馏分中抽提得到,这种方法价格低廉,经济上占优势,是目前世界上丁二烯的主要来源。
根据所用溶剂的不同,该生产方法又可分为乙睛法(ACN法)、二甲基甲酰胺法(DMF法)和N-甲基吡咯烷酮法(NMP法)3种。
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(ACN)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。
目前,该方法以意大利SIR工艺和日本JSR工艺为代表。
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N-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7.5万吨/年生产装置。
公司于1965年实现工业化生产,并建成一套4.5万吨/年生产装置。
N-甲基吡咯烷酮法,N-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7.5万吨/年生产装置。
也是目前国内主要生产方法。
本次毕业设计结合吉林化工有机合成厂采用乙腈法(CAN法)年产14万吨丁二烯工艺,通过已给出的数据进行物料衡算,热量横算,设备计算和换热器等计算完成年产12000吨丁二烯的精馏工艺设计,并进行工艺流程图,设备布置图,设备配管图等设计与绘制,将所学系统知识与实际相联系。
关键词:丁二烯,乙腈法,C4馏分,物料衡算AbstractButadiene is an important organic raw materials based on petrochemicals and synthetic rubber monomer is a C4 fraction of one of the most important component in the oldfins petrochemical raw materials position second only to ethylene and propylene,Because of its molecular conjugated diene contains.you can replace the occurrence of ,addition,cyclization and polymerization reactions,etc.making synthetic rubber and in the area of organic synthesis with a wide range of uses,synthetic butadiene rubber(BR),styrene elastomer(SBR),acrylonitrile-butadiene rubber,styrene-butadiene-styrene elastomer(SBS),acrylonitrile-butadiene-sevrene(ABS)resin and other products,Coated with a very wide range.Nowadays,the main source of butadiene,there are two,one is from a by-product of ethylene cracker mixed C4 fraction has been extracted,this method inexpensive anf economically dominant,is the world’s butadiene the main source.Another fraction from the refinery C4 dehyogenation,that the mothed only in the number of tbutane,butene few resorce-rich countries,The world ftom the pyrolysis of butadiene C4 fraction to extractive distillation extraction method mainly used in accordance with different production methods of solvent acetomitrile method main (ACN),the DMF method DMF)and N-Law methy1 pyrrolidone(NMP Law)3,is the major production methods.Acetonitrile Act, which was first developed by the U.S. Shell, and industrial production in 1956. 10% of it water acetonitrile (ACN) as solvent, by extraction, flash, compression, high-pressure desorption, low-pressure processes such as desorption and solvent recovery unit. Currently, the method to the Italian SIR process and represented Japan JSR process. Dimethylformamide method, dimethylformamide method (DMF method), also known as GPB law, by the Japanese Zeon method of N-methyl pyrrolidone (NMP Method) developed by the German company BASF, and industrial production in 1968 to build a 75,000 tons / year production plant. Company in 1965 industrial production, and the completion of a 45,000 tons / year production plant. N-methyl pyrrolidone method. Method of N-methyl pyrrolidone (NMP method) developed by the German company BASF, and industrial production in 1968 to build a 75,000 tons / year production plant. Is currently the main production methods.The combination of Jilin Chemical graduation organic synthesis plant using acetonitrile (CAN method) produce 140,000 tons of butadiene process, the data has been given by the material balance, heat horizontal count, equipment, heat exchangers and other computing and computing complete an annual output of 12,000 tons of butadiene distillation process design, and conduct process flow diagram, equipment layout, equipment, piping design and drawing maps, etc., will have learned the system of knowledge and practice.Keywords: butadiene, acetonitrile, C4 fractions, material balance, extractive distillation第一篇设计说明书第一章总说明1.1工业生产状况1.2丁二烯的性质及其用途1.3本设计的指导思想1.4设计依据第二章工艺说明书2.1吉林市的自然环境条件2.2生产原料状况2.3原料,辅助物料,成品的主要特性2.3.1原料规格2.3.2工艺条件2.3.3成品丁二烯2.3.3.1产品规格2.3.3.2副产品规格2.3.3.3性质2.4工艺条件2.4.1萃取精馏系统2.5三废处理及防火防爆2.5.1三废处理2.5.2防火防爆2.6车间定员2.7分析项目2.8测量,控制仪表与控制要求2.8.1过程监控与控制要求第二篇设计计算书第一章精馏塔物料衡算1.1脱重塔各组分的饱和蒸汽压1.2想平衡常数与相对挥发度1.3最少理论板数1.4非关键组分的馏出液与釜液的摩尔流率1.5托轻塔和蒸汽压计算1.6相衡常数与相对挥发度1.7脱轻论板数1.8非关键组分塔顶镏岀液及塔釜液的摩尔流率第二章热量横算2.1重塔的最小回流比Rm,实际回流比R2.2塔的理论版N及进料板位置N进2.3脱轻最小回流比Rm,实际回流比R2.4塔的理论板数N及进料板位置N进2.5脱重塔塔顶,塔釜温度2.6脱轻塔的塔顶,塔釜热量横算2.7脱重塔的塔顶,塔釜热量横算2.8脱轻塔的塔顶,塔釜热量横算第三章塔设备工艺尺寸计算3.1平均摩尔质量3.2平均密度3.3液体平均粘度3.4液体平均表面张力3.5塔径计算3.6脱重塔精馏段的塔板工艺结构设计3.6.1堰及降液管设计3.6.2塔板布置3.6.3浮阀布置3.7流体力学计算3.8塔板负荷性能图3.9脱重塔提馏段的塔板工艺结构设计3.9.1堰及降液管的踏板工艺结构设计3.9.2塔板布置3.9.3浮阀布置3.10流体力学计算3.11塔板负荷性能图3.12平均摩尔质量3.13平均密度3.14液体平均粘度3.15液体平均表面张力3.16塔径计算3.16.1精馏塔塔径3.16.2提馏段塔径3.17脱轻塔精馏段的塔板工艺结构设计3.17.1堰及降液管设计3.17.2塔板布置3.17.3浮阀布置3.18流体力学计算3.19塔板负荷性能图3.20脱轻塔提馏段的塔板工艺结构设计3.20.1堰及降液管设计3.20.2塔板布置3.20.3浮阀布置3.21流体力学计算3.22塔板负荷性能图3.23塔高3.23.1塔效率3.23.2塔的实际板数及进料位置3.23.3塔高第四章换热器工艺尺寸计算4.1确定设计方案4.1.1选择换热器的类型4.1.2流动空间及流速的确定4.2确定物性数据4.3计算传热面积4.3.1传热量4.3.2盐水用量4.3.3平均传热量Δtm4.3.4换热器的选取4.3.5校核传热系数1管内盐水的对流传热系数ai 2管外有机蒸汽的对流传热系数ao4.3.6计算传热面积4.3.7换热器内流体的流动阻力1管程流动阻力2壳程阻力第五章选泵5.1泵的选型5.2泵的必需汽蚀余量NPSHr核算第六章选管6.1脱重塔6.2脱轻塔结论参考文献附录A主要符号说明69致谢第一篇设计说明书第一章总说明1.1工业生产状况目前, 世界丁二烯的来源主要有两种, 一种是从乙烯裂解装置副产的混合C4馏分中抽提得到, 这种方法价格低廉, 经济上占优势, 是目前丁二烯的主要来源。