加氫工藝的改進(jìn)
Improvement of hydrogenation process
加氫反應(yīng)器出口硫含量分布,分子結(jié)構(gòu)較為簡(jiǎn)單且副反應(yīng)較少的COS與CS2含量共計(jì)約67mg/m3;加氫**較差、且易發(fā)生副反應(yīng)的硫醇、噻吩含量約為35mg/m3,因此需要分別設(shè)計(jì)具有針對(duì)性的脫除方案。
The distribution of sulfur content at the outlet of hydrogenation reactor, the content of COS and CS2 with simple molecular structure and less side reactions is about 67mg / m3; The content of mercaptan and thiophene with poor hydrogenation * * and prone to side reactions is about 35mg / m3, so targeted removal schemes need to be designed respectively.
2.1COS與CS2的脫除方案
2.1cos and CS2 removal scheme
一般情況下含硫化合物的加氫**與其結(jié)構(gòu)有很大關(guān)系,結(jié)構(gòu)復(fù)雜的含硫化合物往往加氫**較差,由于COS與CS2本身結(jié)構(gòu)較為簡(jiǎn)單,加氫反應(yīng)速度也很快,因此COS與CS2的加氫反應(yīng)比較容易發(fā)生且受到的干擾較少。由此看來(lái),只需增加一*加氫催化劑的裝填量即可滿足工藝指標(biāo)。但由于加氫反應(yīng)器無(wú)法繼續(xù)加裝催化劑,因此在一*加氫反應(yīng)器前增加預(yù)加氫反應(yīng)器。電動(dòng)液壓煙氣擋板門采用金屬硬密封和石墨軟密封的密封方式,保證閥門的氣密性,無(wú)內(nèi)泄外漏。
In general, the hydrogenation * * of sulfur-containing compounds is closely related to their structure. The hydrogenation * * of sulfur-containing compounds with complex structure is often poor. Because the structure of COS and CS2 is relatively simple and the hydrogenation reaction speed is very fast, the hydrogenation reaction between COS and CS2 is relatively easy to occur and less disturbed. Therefore, it is only necessary to increase the loading amount of hydrogenation catalyst to meet the process index. However, since the hydrogenation reactor cannot continue to be equipped with catalyst, a pre hydrogenation reactor is added before the first hydrogenation reactor. The electro-hydraulic flue gas baffle door adopts the sealing mode of metal hard seal and graphite soft seal to ensure the air tightness of the valve without internal leakage and external leakage.
2.2硫醇與噻吩的脫除方案
2.2 removal scheme of mercaptan and thiophene
綜上所述,脫除效率的高低主要取決于加氫環(huán)節(jié),由于結(jié)構(gòu)復(fù)雜、加氫**相對(duì)較差等特性,硫醇、噻吩等硫化物才是加氫反應(yīng)的關(guān)鍵步驟。H2S的存在主要有兩方面影響:(1)與烯烴反應(yīng)生成了新的硫醇和噻吩;(2)抑*了噻吩的氫解反應(yīng)。因此可以推斷H2S含量越低,硫醇與噻吩的加氫轉(zhuǎn)化率越高。因此,將氧化鐵脫硫槽A中的催化劑更換為兼具加氫與脫硫**的鐵錳催化劑,同時(shí)在氧化鐵脫硫槽B的上半部裝填一部分鐵鉬催化劑,使煤氣經(jīng)過(guò)一*加氫后入鐵錳脫硫槽,將轉(zhuǎn)化來(lái)的H2S盡可能脫除后再進(jìn)行加氫反應(yīng),以除去H2S對(duì)硫醇、噻吩加氫反應(yīng)的影響。電動(dòng)液壓煙氣擋板門采用三層防腐設(shè)計(jì),保證閥體不輕易腐蝕。
To sum up, the removal efficiency mainly depends on the hydrogenation link. Due to the complex structure and relatively poor hydrogenation * *, mercaptan, thiophene and other sulfides are the key steps of hydrogenation reaction. The existence of H2S has two main effects: (1) it reacts with olefins to produce new mercaptans and thiophenes; (2) The hydrogenolysis of thiophene was inhibited. Therefore, it can be inferred that the lower the H2S content, the higher the hydrogenation conversion of mercaptan and thiophene. Therefore, replace the catalyst in iron oxide desulfurization tank a with iron manganese catalyst with both hydrogenation and desulfurization * *, and fill part of iron molybdenum catalyst in the upper half of iron oxide desulfurization tank B to make the gas enter the iron manganese desulfurization tank after one * hydrogenation, remove the converted H2S as much as possible, and then conduct hydrogenation reaction, so as to remove the influence of H2S on mercaptan and thiophene hydrogenation reaction. The electro-hydraulic flue gas baffle door adopts three-layer anti-corrosion design to ensure that the valve body is not easily corroded.
2.3原料煤氣凈化方案
2.3 feed gas purification scheme
為了防止原料煤氣夾帶的焦油、洗油雜質(zhì)進(jìn)入加氫反應(yīng)器,引起催化劑床層結(jié)焦、阻力上升,決定在加氫前增加2個(gè)**炭過(guò)濾器,進(jìn)一步除去煤氣中含有的油類雜質(zhì)。
In order to prevent the tar and wash oil impurities carried by the feed gas from entering the hydrogenation reactor, causing coking and rising resistance of the catalyst bed, it is decided to add two * * carbon filters before hydrogenation to further remove the oil impurities contained in the gas.
通過(guò)對(duì)煤氣精脫硫生產(chǎn)裝置的運(yùn)行數(shù)據(jù)進(jìn)行研究,得到以下結(jié)論。
Through the research on the operation data of gas fine desulfurization production unit, the following conclusions are obtained.
(1)加氫反應(yīng)器阻力大是由于原料煤氣夾帶的焦油、洗油、汽輪機(jī)油等物質(zhì)在高溫環(huán)境下發(fā)生聚合、結(jié)焦等現(xiàn)象所致。
(1) The high resistance of hydrogenation reactor is due to the polymerization and coking of tar, wash oil, turbine oil and other substances entrained by feed gas in high temperature environment.
(2)影響精脫硫裝置脫硫效率的關(guān)鍵環(huán)節(jié)是加氫過(guò)程,而控制加氫總效率的關(guān)鍵環(huán)節(jié)是硫醇、噻吩的加氫反應(yīng)。
(2) The key link affecting the desulfurization efficiency of the fine desulfurization unit is the hydrogenation process, and the key link controlling the total hydrogenation efficiency is the hydrogenation reaction of mercaptan and thiophene.
(3)烯烴和H2S的反應(yīng)影響了硫醇、噻吩的脫除效率。
(3) The reaction between olefins and H2S affects the removal efficiency of mercaptan and thiophene.
(4)H2S的存在抑*了噻吩的加氫反應(yīng)。
(4) The presence of H2S inhibited the hydrogenation of thiophene.
(5)H2S含量越低,硫醇、噻吩的加氫轉(zhuǎn)化率越高。
(5) The lower the H2S content, the higher the hydrogenation conversion of mercaptan and thiophene.
The above is a detailed introduction of dry desulfurization. I hope it will help you If you have any questions, please contact us We will provide service for you with professional attitude http://www.mimi5.cn