After the start-up of the 3.8 MMTPY large-scale continuous reforming unit of Zhejiang Petro-leum&Chemical Co.,Ltd.,the pressure difference of the regenerated catalyst dust collector continued to rise,resulting in multiple fluctuations in processing load.The regeneration system was forced to shut down due to collector cleaning,seriously affecting the full load operation of the unit and the company's economic bene-fits.To address the above issues,technical transformation was carried out.After the renovation,the fluctua-tion range of pressure difference in the riser has been reduced by about 6 kPa,greatly alleviating the wear of catalyst particles,reducing the dust amount by 1.93 kg/d,and stabilizing the pressure difference of the dust collector at 6.2 kPa,extending the operating time.
The disproportionation unit is an important component of aromatics complex.Comparing the calibration results of the ex-situ regenerated disproportionation catalyst with the technical agreement values of the new catalyst,it is found that the performance of the ex-situ regenerated catalyst can basically reach the lev-el of the new catalyst.The operational data of the first four months after the operation of the in-situ and ex-situ regenerated catalysts are compared.At similar weight hourly space velocity,the total conversion rate of the ex-situ regenerated catalyst is slightly lower than that of the in-situ regenerated catalyst,while the total selectivity is slightly higher and the hydrogen consumption is slightly lower.As the operating time prolongs,the in-situ regenerated catalyst maintains operation at a high weight hourly space velocity,and the reaction temperature slightly increases;when the operating load of the in-situ regenerated catalyst is 105.4%,the total conversion rate decreases by 2.2 percentage points,and the total selectivity slightly decreases by 0.5 percentage points;the weight hourly space velocity and reaction temperature of the ex-situ regenerated catalyst are relatively low,which may be related to the slightly lower processing capacity of the selected unit;when the operating load of the ex-situ regenerated catalyst is 92.3%,the total conversion rate decreases by 2.45 percentage points,the total selectivity increases by 1.21 percentage points,and the chemical hydrogen consumption decreases by 0.1 percentage points.In addition,if conditions permit,the total conversion rate of the reaction should be con-trolled between 42%and 44%to balance catalyst deactivation rate,selectivity and energy consumption.
Sulfur is a special chemical raw material,which is consumed in large quantities and highly de-pendent on imports in China.With the development and production of high sulfur gas fields in China,acid gas has become the main source of sulfur for domestic production.Faced with the challenges of small scale and high cost of traditional dry molding,Puguang Gas Field has innovatively developed a series of technologies such as efficient wet molding,precise dust prevention and control,and safe and green storage,establishing the largest sulfur production base in Asia.By revealing the large-scale solidification law of liquid sulfur,the first wet molding equipment in China has been developed,with a monomer capacity of 90 t/h and a product quality rate of 100%.Revealed the law of sulfur dust explosion,built the first full process dust prevention and control system,with a gas phase dust concentration less than 3 mg/m3.The 50 dam3 liquid sulfur storage sys-tem and 114 kt solid sulfur storage system have been built,and the scattered waste gas has been comprehen-sively utilized as a resource.The successful application of the complete set of technologies for sulfur wet mold-ing and safe and green storage has reduced China's dependence on sulfur imports by 26 percentage points.
A new generation of low-pressure hydrogenation technology was adopted for hydrofining to ex-pand the distillation range and increase the production of No.3 jet fuel.The jet fuel product was subjected to a one-year storage test.A comparative analysis was conducted on the feedstocks before and after the adoption of the new technology.The results showed that the properties of the expanded feedstocks decreased compared to the original process,with little change in hydrocarbon composition.The density,sulfur content and nitrogen content increased significantly while its smoke point went down and its naphthalene-hydrocarbon content increased twice,and its freezing point rising from-59.9℃to-51.0℃,but the product was still qualified No.3 jet fu-el.The properties of the new product and the product after storage for 1 a were fully analyzed and compared ac-cording to the No.3 jet fuel product standard.At the same time,the key items such as dynamic thermal oxida-tion stability breaking point and static thermal oxidation stability precipitation were compared and analyzed.The results showed that the results of full analysis items changed slightly during the storage of jet fuel with extended distillation range,but they were still qualified.The breaking point of dynamic thermal oxidation stability was greater than 300℃,the static oxidation precipitation was not greater than 0.5 mg/100 mL,and the mass frac-tion of basic nitrogen was less than 1 μg/g.The key indicators were better than the requirements of the No.3 jet fuel standard,and the product yield increased by 47.7%compared to before expanding the distillation range.
照片为中石化广州工程有限公司作为专利商和承包商承担的天津渤化化工发展有限公司 180 万吨/年甲醇制烯烃装置,是在总结陕西蒲城首套DMTO-Ⅱ大型化工业装置成功经验基础上进行工艺与工程技术再创新建设的一个甲醇制烯烃项目.
