Sulfur removal from hydrotreated petroleum fractions using ultrasound-assisted oxidative desulfurization process

Ultrasound-assisted oxidative desulfurization (UAOD) process was applied to diesel oil and petroleum product feedstock containing model sulfur compounds (benzothiophene, dibenzothiophene and dimethyldibenzothiophene). The influence of oxidant amount, volume of solvent for the extraction step and time and temperature of ultrasound treatment (20 kHz, 750 W, operating at 40%) was investigated. Using the optimized conditions for UAOD, sulfur removal up to 99% was achieved for model compounds in petroleum product feedstock using a molar proportion for H₂O₂:acetic acid:sulfur of 64:300:1, after 9 min of ultrasound treatment at 90 °C, followed by extraction with methanol (optimized solvent and oil ratio of 0.36). Using the same reagent amount and 9 min of ultrasound the removal of sulfur was higher than 75% for diesel oil samples. Sulfur removal without ultrasound using the same conditions was lower than 82% for model compounds and 55% for diesel oil samples showing that ultrasound improved the efficiency of oxidative desulfurization. In comparison to conventional hydrodesulfurization, the proposed UAOD process can be performed under relatively mild conditions (atmospheric pressure and 90 °C, without using metallic catalysts).     

Feasibility of using ultrasound-assisted process for sulfur and ash removal from coal

The present work investigates utilization of ultrasound in reagent-based coal de-ashing and de-sulfurization. The coal under study was received from Girald mine, Rajasthan, India. Three different ultrasonic frequencies (25 kHz, Dual (58/192 kHz) and 430 kHz) and three reagents (HCl, HNO₃ and H₂O₂) were used. The study employed a Taguchi fractional-factorial L₂₇ DOE. Experimental data were used to derive an empirical model for the prediction of total sulfur removal. The model incorporates cavitational intensity, reagent concentration, sonication time, coal particle size and coal concentration as key parameters. Effects of above factors on reagent-based ultrasonic coal-desulfurization are presented here. An optimum set of process parameters are identified and validated. Larger-scale trial with high-ash and high-sulfur coals is strongly recommended.     

干法乙炔脱硫

论述了干法乙炔生产中去除乙炔气体中H2S杂质的工艺计算和工艺指标的控制,解决了干法乙炔清净不合格的问题。     

Extraction conditions for removal of oxidized sulfur compounds in gas oil

An experimental study was conducted to investigate the extraction of oxidized sulfur compounds from gas oil. Solvents used for this purpose included acetone, acetonitrile, methanol and propanol. The effect of solvent concentration, solvent to gas oil ratio, temperature, time and number of stages was studied. To select the best solvent and conditions for extraction, two criteria were considered: high desulfurization and more hydrocarbon recovery. Results showed that extraction time and temperature have no significant effect. Methanol for low ability of extraction of oxidized sulfur compounds and propanol for low hydrocarbon recovery were excluded from further experiments. After the tests, the optimum conditions for extraction were determined to be 85% acetone, solvent/feed ratio of 1, two stages extraction in ambient temperature and enough time for mixing. In this condition 85% of sulfur compounds of gas oil containing 1,670 ppmw S were separated and 95% of gas oil was recovered.     

Sulfur oxidative coupling of methane process development and its modeling via machine learning

Sulfur oxidative coupling of methane (SOCM) has seen a significant improvement in catalyst design and performances, but there is still a lack of development at process level. We propose an optimized SOCM process flow diagram, with integrated waste heat recovery system and an efficient separation technique. The outcomes of the simulated process were used to design a data-driven modeling approach, based on machine learning methods, and to evaluate its interpolation accuracy. The simultaneous multi-input/multioutput relationship between the different parameters of the SOCM system were determined, revealing the optimum reaction conditions for the maximum benzene, toluene and xylene yield, at the minimum CH₄ and H₂S recycling rate.     

Sensitivity analysis of a light gas oil deep hydrodesulfurization process via catalytic distillation

In this work, a sensitivity analysis of a light gas oil deep hydrodesulfurization catalytic distillation column is presented. The aim is to evaluate the effects of various parameters and operating conditions on the organic sulfur compound elimination by using a realistic light gas oil fraction. The hydrocarbons are modeled using pseudocompounds, while the organic sulfur compounds are modeled using model compounds, i.e., dibenzothiophene (DBT) and 4,6-dimethyl dibenzothiophene (4,6-DMDBT). These are among the most refractive sulfur compounds present in the oil fractions. A sensitivity analysis is discussed for the reflux ratio, bottom flow rate, condenser temperature, hydrogen and gas oil feed stages, catalyst loading, the reactive, stripping, and rectifying stages, feed disturbances, and multiple feeds. The results give insight into the qualitative effect of some of the operating variables and disturbances on organic sulfur elimination. In addition, they show that special attention must be given to the bottom flow rate and LGO feed rate control.     

Hydrogen sulfide removal by catalytic oxidative absorption method using rotating packed bed reactor

Using catalytic oxidative absorption for H_2S removal is of great interest due to its distinct advantages. However,traditional scrubbing process faces a great limitation in the confined space. Therefore, there is an urgent demand to develop high-efficiency process intensification technology for such a system. In this article, H_2S absorption experimental research was conducted in a rotating packed bed(RPB) reactor with ferric chelate absorbent and a mixture of N_2 and H_2S, which was used to simulate natural gas. The effects of absorbent p H value, gas–liquid ratio, gravity level of RPB, absorption temperature and character of the packing on the desulfurization efficiency were investigated. The results showed that H_2S removal efficiency could reach above 99.6% under the most of the experimental condition and above 99.9% under the optimal condition. A long-time continuous experiment was conducted to investigate the stability of the whole process combining absorption and regeneration. The result showed that the process could well realize simultaneous desulfurization and absorbent regeneration, and the H_2S removal efficiency kept relatively stable in the whole duration of 72 h. It can be clearly seen that high gravity technology desulfurization process, which is simple, high-efficiency, and space intensive, has a good prospect for industrial application of H_2S removal in confined space.     

磷钨酸烷基甜菜碱催化氧化燃料油脱硫的性能

以磷钨酸烷基甜菜碱为相转移催化剂,双氧水为氧化剂,在乳液体系下,催化氧化脱除燃料油中的硫化物,研究了磷钨酸十四烷基二甲基甜菜碱、磷钨酸十六烷基二甲基甜菜碱以及磷钨酸十八烷基二甲基甜菜碱的催化性能,考察了催化剂用量、制乳时间、制乳转速以及氧硫比对脱硫效果的影响。结果表明,烷基甜菜碱的烷基链越长,催化效果越好;在催化剂的用量为0.003（剂油比）、制乳时间8min、制乳转速2500r/min、氧硫比为11的条件下,脱硫率可达到91.23%。     

Effect of process conditions on the removal of phospholipids from Jatropha curcas oil during the degumming process

This work aims to study the removal of phospholipids from Jatropha oil through a conventional degumming process combined with ultrafiltration membrane separation in a small-scale batch system. The effect of temperature, amount of acid solution added, and speed of centrifugation during the conventional degumming process were analyzed using response surface methodology (RSM). The optimum operating condition was determined to be at 65 °C, with 4 wt% acid solution added and a centrifugation speed of 1600 rpm. After the degumming process, the phospholipid content of Jatropha oil was reduced from 1200 ppm to 60 ppm. This was further reduced to less than 20 ppm by subjecting the oil to ultrafiltration membrane separation. It was found that the entire process not only decreased the phospholipid content of the oil but also improved its fuel properties, especially its kinematic viscosity and carbon residue. The kinematic viscosity was decreased from 30.02 cSt (mm²/s) to 27.20 cSt, while the carbon residue was decreased from 7.8% to 4.0%. Aside from the phospholipid content, the other two properties mentioned above were also considered to be important in the use of pure plant oil as a fuel in diesel engines. Future research could investigate the integration and optimization of the conventional degumming process combined with a membrane separation process.     

碱渣脱除锌冶炼烟气中SO2的工艺

利用水合肼生产过程中副产的碱渣(含Na2CO3.10 H2O)吸收锌冶炼烟气,得到结晶亚硫酸钠。重点考察了尾气中SO3含量、碱液比重、中和液pH值对脱SO2工艺、效率和产品的影响。     

离子液体中钨酸盐催化氧化模拟汽油脱硫研究

随着燃料油中硫化物含量的标准限值越来越严格,对燃料油中硫化物的脱除工艺技术也提出了更高的要求。合成了十聚钨酸十六烷基三甲基铵[C_(16)H_(33)N(CH_3)_3]_4W_(10)O_(32)和离子液体[Omim]PF_6,分别作为催化剂和萃取剂,构建了[C_(16)H_(33)N(CH_3)_3]_4W_(10)O_(32)/[Omim]PF_6/H_2O_2催化氧化萃取耦合脱硫体系,用于模拟汽油中硫化物二苯并噻吩(DBT)的脱除研究。考察了H_2O_2用量、反应温度、反应时间和催化剂[C_(16)H_(33)N(CH_3)_3]_4W_(10)O_(32)用量对DBT脱除率的影响,结果表明:在H_2O_2与S的摩尔比为4、反应温度50℃、反应时间60 min、催化剂与S的摩尔比为0.02、离子液体与模拟汽油体积比为0.2的条件下,DBT脱除率最高,可达98.6%。     

锅炉烟气脱硫除尘与渣浆水的综合利用

介绍了锅炉烟气脱硫、除尘工艺的主要特点以及废渣浆水的综合利用，治理后的效果以及存在的主要问题。     

Effect of process conditions on the composition of products in the conventional and deep catalytic cracking of oil fractions

With the purpose of increasing the yield of light C₂-C₄ olefins in comparison with that in conventional catalytic cracking, we experimentally study the effect of temperature and catalyst-to-oil ratio on the distribution of the basic products of oil catalytic cracking on the bizeolite and industrial LUX catalysts. The bizeolite catalyst contains ZSM-5 and ultrastable Y zeolites in equivalent amounts, while the LUX catalyst contains 18 wt % of Y zeolite in the HRE form. As shown by the results of our tests, the yield of C₂-C₄ olefins and gasoline in the deep catalytic cracking of hydrotreated vacuum gasoil on the bizeolite catalyst within a range of catalyst-to-oil ratios of 5–7 and temperatures of 540–560°C reaches 32–36 and nearly 30 wt %, respectively. In cracking on the LUX catalyst under similar conditions, the yield of light olefins and gasoline is 12–16 and 37–45 wt %, respectively. The distribution of target products in the deep catalytic cracking of different hydrocarbon fractions (vacuum gasoil, gas condensate, its fraction distilled from the cut boiling below 216°C, and the hydrocracking heavy residue) on the bizeolite catalyst is studied. It is shown that the fractions of gas condensate and hydroc-racking residue can serve as an additional source of hydrocarbon raw materials in the production of olefins.     

天然气脱酸气工艺方案优选研究

借鉴塔设备4因素模糊工业评价法,提出5因素模糊工业评价法,并将其用于一示范气田。结合示范气田脱酸气工艺参数推荐范围,列出所有参数组合方案,选取5个能综合反映工艺性能的指标作为评价因素,给出评价方法涉及的所有集合,确定各方案的单因素评价矩阵及综合评价集,最终给出各方案的综合评价分值,以此推选出最优工艺方案。     

Computer-aided process engineering in oil and gas production

As oil and gas production moves to ever more challenging areas, increased use of technology becomes increasingly important. One technology that can contribute towards achieving safe and economic production from such areas is computer-aided process engineering. The use of such technology is outlined for two (of many) instances: Managed pressure drilling (MPD) for deep-offshore applications and natural gas production from shales. A broader picture of the importance of computer-aided process engineering for energy is briefly touched upon.     

电站煤流化床混合气催化气化工艺条件的研究

在一小型流化床中,对阳泉电站无烟粉煤Ⅰ、Ⅱ在工业固碱与黏胶废碱液2种催化剂作用下进行混合气催化气化,指出适宜的催化气化温度均为900℃,2种催化剂对无烟粉煤Ⅰ、Ⅱ的适宜添加质量分数分别为8%与6%.无烟煤Ⅱ比无烟煤Ⅰ有更好的反应活性,工业黏胶纤维废碱液比工业固碱的催化效果更好,使产气率与煤转气热值明显增高,并降低了催化剂成本,防止了环境排放污染.     

杂多酸的共价负载及其对四氢噻吩氧化性能研究

首先采用改进的Hummers法制备氧化石墨烯（GO）,用3-氨丙基三甲氧基硅氧烷（KH540）对GO进行表面改性,制得氨基改性氧化石墨烯NH₂-GO。然后,通过γ-(2,3-环氧丙基) 三甲氧基硅烷对单缺位的Dawson型磷钨酸盐K₁₀[α-P₂W₁₇O₆₁]·20H₂O（P₂W₁₇）进行环氧基改性,制得环氧基改性的EPO-P₂W₁₇。最后,借助NH₂-GO与EPO-P₂W₁₇之间的席夫碱反应实现P₂W₁₇在GO上的共价固载,制得复合催化剂P₂W₁₇/GO。采用FT-IR、UV-Vis、TG、XPS、TEM等对复合材料的结构和组成进行了表征。以四氢噻吩（THT）作为催化评价的对象,初步考察了P₂W₁₇/GO的催化氧化活性。实验结果表明,共价负载在GO上的P₂W₁₇分散性良好,且复合催化剂P₂W₁₇/GO对THT表现出良好的催化活性和高的选择性。较小的P₂W₁₇/GO用量（0.02 g）下,以H₂O₂为氧化剂,反应75 min,THT转化率达100%;相对于EPO-P₂W₁₇,其催化活性提高了1.7倍;其催化H₂O₂氧化THT的过程符合准一级动力学模型。此外,该催化剂具有良好的重复使用性。     

Multi-model based process condition monitoring of offshore oil and gas production process

Offshore oil and gas production platforms are uniquely hazardous in which the operating personnel have to work in a perilous environment surrounded by extremely flammable hydrocarbons. A failure in an equipment could quickly propagate to others resulting in leaks, fires and explosions, causing loss of life, capital invested and production downtime. A method for preventing such accidents is to deploy intelligent monitoring tools which continuously supervise the process and the health of equipments to provide context-specific decision support to operators during safety-critical situations. Such an intelligent system, which is condition driven is developed and described in this paper. Since relevant process data is unavailable in the literature, a dynamic model of an offshore oil and gas production platform was developed using gPROMS and data to reflect operating conditions under normal, fault conditions and maintenance activities were simulated. The different maintenance activities and normal conditions are explicitly considered as separate states of the process. The simulated data are then used to train principal component analysis monitoring models for each of these states. Online fault detection and identification are performed by identifying the operating state in real-time and triggering the respective model. In this paper, the dynamic model and the condition monitoring system are described.     

混合废塑料与焦化蜡油共催化裂解制取燃料油

以混合废塑料和焦化蜡油为原料,共催化裂解制备燃料油,克服了废塑料裂解中塑料粘稠度大且传热效率低、裂解炉中温度极不均匀、反应时间长、气体和固体收率高、液体收率低和易结焦等难题。详细考察焦化蜡油与混合废塑料质量比和催化剂用量对产物组成的影响以及FCC催化剂的重复使用性能。结果表明,在焦化蜡油与混合废塑料质量比为2、FCC催化剂用量为混合废塑料质量的10%、终温460 ℃并保持4 h条件下,燃料油收率达到96.67%,气体收率和釜残率分别仅有0.27%和1.53%。焦化蜡油的添加使液相产物中重组分增多,轻组分减少。FCC催化剂的重复使用性能好,催化剂重复使用5次,液体收率大于85%。采用混合废塑料与焦化蜡油共催化裂解的工艺不仅为“白色污染”的处理开辟了一条新途径,而且扩大了焦化蜡油的应用范围。