渣油掺炼煤焦油的减压蒸馏过程

为提高资源利用率,考察了掺炼煤焦油对渣油减压蒸馏的影响。结果表明,在渣油中掺炼一定比例的煤焦油可以提高其减压蒸馏的拔出率,为后续加工提供更多的原料。相比较于纯渣油,在550℃对渣油掺炼20%的煤焦油进行蒸馏,可多获得近15个百分点的催化裂化加工原料。扣除煤焦油馏分油后,渣油的拔出率也提高5个百分点。同时,蒸馏残渣的软化点有一定的提高,更适合用做沥青原料。最后探讨了煤焦油对渣油蒸馏过程的强化机理。     

Isolation of prime value products from crude xylenol fraction of noncaking coal-derived tar acids

An efficient method for the separation of prime value products from crude xylenol fraction of noncaking coal-derived tar acids involving suitable distillation technique is described. The feed as well as the products was analysed by gas chromatography (G.C.). The crude xylenol comprising a number of close-boiling phenolic compounds was fractionated under reduced pressure to yield three cuts, viz. cresols (30.7%), xylenols (31.2%) and dihydric phenols (23.3%). The dihydric phenols fraction termed as high boiling tar acids (HBTA) was found to contain significant amounts of catechol (6.4%), methyl catechols (32.3%), resorcinol (12.7%) and methyl resorcinols (8.6%). Catechol together with its homologues and resorcinol with its homologues were isolated from the HBTA. These products, not available from the HBTA of metallurgical coke plants, have been shown to offer distinct marketing advantages. A conceptual scheme for the treatment of crude xylenol as well as application pattern of various products obtainable from the crude mixture is presented.     

Production methods for the manufacture of crude tall oil and its subsequent processing

Summary The source of crude tall oil and methods to produce the oil have been described. These include acidulation of sulfate pulp, black liquor skimmings, and gravity settling as well as centrifugal means of separation to reduce the lignin content of the product. Subsequent processing of the crude tall oil into fractionated fatty acids and rosin has been outlined with suggestions for consideration in all stages of the distillation section of the plant.     

提高酚产品收率的几点措施

酚产品收率低的主要原因是：焦油加工车间酚油和素油的酚集中度低、馏分碱洗脱酚和废水萃取脱酚过程中乳化物多；酚盐分解时一些挥发酚进入大气；粗酚精制后酚渣中遗留的二甲酚和高级酚大多。要提高焦化企业的酚收率，除改进工艺制度及认真操作外，还要严格控制入萃取塔的废水质量及焦炉循环氨水质量。同时，应尽量完善设施，诸如设立酚盐分解酸汽吸收塔、酚渣蒸馏等装置。     

中低温煤焦油加氢工艺技术概述

针对煤炭在干馏、气化或热解过程中的副产物——煤焦油的高效清洁利用问题,分析了煤焦油的来源以及煤焦油加氢的目的、作用和原理;以煤热解过程产生的中低温煤焦油的加氢改质处理工艺为例,论述了加氢精制工艺、加氢精制-加氢裂化工艺、液相裂解加氢工艺、非均相悬浮床加氢工艺的优缺点及其在国内加氢改质装置的生产应用效果;结果表明,煤焦油...     

高温煤焦油过滤分离的研究

煤焦油是煤在干馏和气化过程中获得的液体产品。由于煤焦油中的煤粉、焦粉和热解碳等物质的存在,对煤焦油催化加氢制取汽油、柴油存在不利影响,所以在煤焦油加工之前,必须控制其含固质量分数。本实验室以陕西某化工厂的煤焦油为原料,在小型过滤分离装置上采用固液过滤分离法对煤焦油进行了过滤分离实验,目的是降低煤焦油中的含固质量分数。通过过滤分离实验,煤焦油中的含固质量分数大大降低,过滤效果达到90%以上,过滤后的煤焦油可以达到催化加氢制取汽油、柴油的要求。     

焦化脱酚后剩余氨水中溶剂油的回收

焦化剩余氨水经预处理去除大量酚类、煤焦油等,预处理后剩余氨水仍含有少量的油类物质,在蒸氨时不断积累,如不分离这部分油类,则影响蒸氨运行,且造成苯系物损失。本文主要介绍了焦化剩余氨水预处理脱酚后溶剂油的回收工艺。实验表明,此工艺简单有效。     

原料焦油泵机械密封失效分析及技术改进

分析了原料焦油泵机械密封失效的原因,提出了机械密封结构改进方案.通过对机械密封进行改造,提高了密封效果和泵的使用寿命,大大节省了生产成本.     

煤焦油加工工艺研究

伴随大规模油田的开采,生产煤焦油的低温干馏工艺过程逐步淘汰。但国内仍有大量回收的煤焦油,所以要深入分析煤焦油的特点,作为进一步加工的依据,来系统的分析以及指导煤焦油工艺加工的方向以及过程。     

Fractional vacuum distillation of herring oil methyl esters

Methyl esters of a Canadian Atlantic herring oil containing 62% monoethylenic fatty acids were subjected to batch fractional distillation under vacuum on a pilot plant scale, to study the feasibility of fractionating fatty acid esters of marine oils of low iodine value into monounsaturated fractions with increased commercial value for industrial chemical uses. A total of 64 methyl ester fractions were collected and analyzed by gas liquid chromatography. Recoveries of the major saturated and monounsaturated acids were close to 100%, and some fractions contained over 90% of the desired 22:1 long chain monounsaturated acids. The short chain polyunsaturated acids were recovered in good yields, but the long chain highly unsaturated acids were recovered in yields of 60% or less due to oxidative and thermal decomposition in the particular apparatus employed. If small amounts of unsaturated acids are acceptable, fractional distillation of low iodine value marine oils could inexpensively supply fractions with high concentrations of methyl esters of longer chain (C₂₀ and C₂₂) monounsaturated and shorter chain (C₁₄) saturated acid or (C₁₆) saturated-monounsaturated acid mixture.     

Extraction of tar acids from tar oils by aqueous acetamide

Aqueous acetamide has been found to be a good solvent for the extraction of tar acids from low temperature carbonisation tar oils. Saturated acetamide solution at 15–30° in the molar ratio acetamide/tar acids of 3 : 1 effects a recovery of about 90% of tar acids originally present in the oil in two extraction stages. The tar acids are obtained in 77% purity, the impurities consisting of neutral oils and tar bases. Re-extraction with light petroleum can raise the purity of tar acids to 94%. Tar acids can be separated from the purified acetamide extract by suitable dilution with water. The system tar acids—(bases + neutral oils)—saturated aqueous acetamide has been studied. It has been shown that three theoretical counter-current extraction stages are required to effect a recovery of 95% of tar acids from a feed oil containing 45% tar acids. 98% recovery of the tar acids could be achieved in four stages.     

Tall oil fatty acids

About 1949, with the advent of effective fractional distillation, the tall oil industry came of age, and tall oil fatty acids (TOFA), generally any product containing 90% or more fatty acids and 10% or less of rosin, have grown in annual volume ever since, until they amount to 398.8 million pounds annual production in the U.S. in 1978. Crude tall oil is a byproduct of the Kraft process for producing wood pulp from pine wood. Crude tall oil is about 50% fatty acids and 40% rosin acids, the remainder unsaps and residues; actually, a national average recovery of about 1–2% of tall oil is obtained from wood. On a pulp basis, each ton of pulp affords 140–220 pounds black liquor soaps, which yields 70–110 pounds crude tall oil, yielding 30–50 pounds of TOFA. Separative and upgrading technology involves: (a) recovery of the tall oil; (b) acid refining; (c) fractionation of tall oil; and occasionally (d) conversion to derivatives. TOFA of good quality and color of Gardner 2 corresponds to above 97% fatty acids with the composition of 1.6% palmitic & stearic acid, 49.3% oleic acid, 45.1% linoleic acid, 1.1% miscellaneous acids, 1.2% rosin acids, and 1.7% unsaponifiables.     

焦油蒸馏引进工艺的技术特点

介绍了国内首套引进的30万t/a煤焦油蒸馏装置的工艺情况及主要中间馏分质量情况,指出了该装置在产品质量、能量平衡和环境保护等方面的优势,提出了我国煤焦油加工应该改进的方面。     

Corrosion of alloys in tall oil distillation service

Plant corrosion tests of various metals and alloys in tall oil distillation streams present the effect of alloy composition on corrosion rate. Stream temperature, alloy composition and stream composition are correlated so as to provide a useful guide to material selection for tall oil distillation plants. Alloys exposed to corrosion test were iron or nickel base with chromium plus varying amounts of molybdenum. Molybdenum is the most important alloy addition in reducing the rate of corrosion attack, with corrosion attack at a very low rate, <.1 mil per year, at the 6% molybdenum level in the most aggressive stream tested, i.e., 85% fatty acids at 518F. The presence of chromium does not appear to be essential to obtaining good corrosion resistance to the more corrosive conditions. Corrosion rates increase with increasing temperature. The streams classed as high in fatty acids are much more corrosive than those which are classed as high in rosin acids. Vapor phase streams are more corrosive than liquid phase streams. Corrosion attack is normally from pitting. Most of the more corrosive conditions can be handled with an alloy containing 3% to 4% molybdenum (AISI Type 317), but some process conditions require higher molybdenum contents in order to obtain acceptable corrosion rates. Less corrosive streams can be handled with an alloy containing less than 3% molybdenum (AISI Type 316).     

洗油加工和焦油萘蒸馏系统的结渣问题分析

介绍了洗油加工系统和焦油萘蒸馏系统的结渣情况,根据生产实际情况,通过对实际数据的研究分析,提出了结渣问题的解决方法,就是将萘油改送到焦油萘蒸馏装置,与焦油混合后一起蒸馏,使渣残留在重质馏分中,从而避免了渣对洗油加工系统和焦油萘蒸馏系统产生的不利影响。同时,对改变萘油处理途径的优劣进行了分析,为解决该系统的结渣问题提供了参考。     

Recovery of Phenol through the Decomposition of Tar under Hydrothermal Alkaline Conditions

Decomposition of the tar residue from oil distillation was carried out under hydrothermal conditions using a batch reactor at 623–673 K and 25–40 MPa, with and without K₂CO₃ as a catalyst. The reaction scheme for tar decomposition was determined as follows: the liquefaction and dissolution process of tar occur first and then intermediate chemical compounds are transformed into lighter molecular weight species. The presence of K₂CO₃ activates the dissociation of molecular hydrogen to facilitate hydrogenation reactions. The main products from the decomposition of tar were phenol, biphenyl, diphenylether (DPE), and diphenylmethane (DPM). These results indicate that hydrolysis was important in the cleavage of the macromolecular structure of tar under both catalytic and non‐catalytic hydrothermal conditions. This method can be developed for efficient tar liquefaction to generate high yields of valuable chemicals in an environmentally friendly way.     

藻类与煤低温共炭化对低温煤焦油的影响

将不同配比的藻类与煤以低温干馏的方法进行低温共炭化,研究煤焦油的变化.结果表明,煤焦油中轻质油含量增加29.55％,萘类化合物含量增加9.15％,酚类化合物含量增加23.93％,实现一定程度的轻质化.     

低温煤焦油中特定芳烃组分的选择性分离

以研究低温煤焦油中特定芳烃组分的选择性分离为目标, 通过预处理分离酚类化合物和富集特定芳烃组分, 采用多元溶剂萃取方法选择性分离芳烃和非芳烃组分, 采用Hansen溶度参数理论进行多元溶剂的设计和萃取条件的优化。结果表明, 溶剂对原料焦油的选择性随Hansen溶度参数“距离”(R_a)增加而增大, 萃取能力则相反。研究得到的多元萃取剂是含水量为体积分数6%的N,N-二甲基甲酰胺溶液, 优化萃取条件是温度25℃、剂/油比6:1。萃余物经多次萃取进一步分离芳烃组分, 萃出物经甲酰胺多次萃取以分离出杂环化合物和极性组分。芳烃组分在最终分离产物中的质量分数为94%, 其总萃取收率为95%。另外非芳烃化合物、杂环化合物和其他极性组分也在本过程中得到了有效富集。     

煤焦油加氢转化技术

分析了国内已经研究开发的煤焦油加氢转化技术,按照各技术的特点和轻油产品收率将现有煤焦油加氢转化技术划分为轻馏分油固定床加氢精制、减压馏分油固定床加氢裂化、全馏分油固定床加氢裂化、延迟焦化-固定床加氢裂化联合加工、悬浮床和沸腾床加氢裂化5类技术,分别介绍了每种技术的工艺流程特点和发展状况,分析了各自的优缺点、局限性、技术难点和实用性。建议今后应关注煤焦油生产芳烃产品、酚类产品技术的开发,以及开发煤焦油脱水脱盐技术,进一步完善、配套煤焦油加氢转化技术。     

高效破乳剂在焦油氨水分离中的研究与应用

分析了焦化厂焦油氨水分离系统的运行状况,筛选了高效破乳剂对焦油氨水进行分离试验。分离后焦油的含水量低于2.0%,焦油中的萘含量由8.9%升高到11.0%,提高了萘的回收率。