Advantages of Mild Hydrocracking FCC Feed—A Pilot Plant Study

Abstract

In view of increasingly stringent environmental regulations with respect to SOx and particulate emissions, the allowable sulphur and nitrogen levels in diesel and gasoline are reducing all over the world. Fluid catalytic cracking (FCC) unit is a major source of fuels produced from a refinery. Any attempt to reduce sulphur and nitrogen content of distillates produced from FCC unit will greatly improve the quality of fuels. In the present work, pilot plant studies were conducted to evaluate the options of hydrotreating and mild hydrocracking (MHC) of FCC feedstock. Experiments were conducted on commercially available catalyst samples using high nitrogenous vacuum gas oil (VGO) as feedstock. MAT experiments were also conducted to compare the conversions and yields of untreated, hydrotreated, and MHC VGO at constant operating conditions. Pilot plant data showed that MHC of VGO would produce additional fuels to the extent of 15% under moderate operating conditions besides improving the quality of FCC feedstock. The mild hydrocracked VGO as feed was found to increase FCC conversion by 2 wt%, increase fuels by 2.5 wt%, reduce residue by 2.8 wt% compared to untreated vacuum gas oil.     

Application of Zeolite Y-Based Ni–W Supported and In Situ Prepared Catalysts in the Process of Vacuum Gas Oil Hydrocracking

The activity of supported and in situ synthesized sulfide Ni–W catalysts based on a low-silicon zeolite Y (SiO₂/Al₂O₃ = 5.2) in the hydrocracking of vacuum gas oil is studied. It is shown that the temperature and time of reaction affect the fractional composition and the sulfur content in conversion products. It is found that the phase of tungsten sulfide as well as the mixed Ni?W?S phase active in hydrogenation are formed on the catalyst surface. It is proposed that an increase in activity for the in situ formed catalyst may be explained by a high content of sulfide phases on the catalyst surface and accessibility of the zeolite pore system.     

In-depth Profile Control Technologies in China—A Review of the State of the Art

Abstract

In the process of waterflooding and polymer flooding, the oil displacement efficiency is poor because of the heterogeneity of reservoirs, the conventional profile control and water shutoff technology can no longer satisfy constantly production demand. So, in-depth profile control technology has been developed in recent years, and an obvious effect is obtained in improving development effects of waterflooding and polymer flooding in high water-cut stage. In this article, in-depth profile control technology is widely analyzed, and a development tendency of this technology is proposed; that is, a complete study of in-depth profile control and polymer flooding should be developed based on the sufficient understanding of reservoir status, advantage channels should be controlled and fluids diverted, and the oil displacement efficiency of waterflooding and polymer flooding for high water-cut stage could be improved.     

A Review of: “Environmental Analysis and Technology for the Refining Industry”

Abstract

The methods of hydrochloric acid extraction, liquid–solid adsorption, and complexation were used to remove basic nitrogen compounds from gasoline, and the efficiencies of three removal methods were studied. The experimental results show that the optimum range of the concentration of hydrochloric acid is 0.05 ～ 1.0 mol L^?1, and the optimum extraction time is 20 min for hydrochloric acid extraction method. The efficiency of removal of basic nitrogen compounds reaches its top when the ratio of liquid to solid is controlled at 5:1, and that the optimum range of concentration of complexing agent is 15 ～ 20 wt% for complexation. Under the conditions mentioned above, all the removal yields of basic nitrogen of these three present methods can exceed 90%.     

Accelerating the Development of Hydrogenation Process and Technology in China

The crude oils processed at refineries worldwide are becom ing heavier with the contents of sulfur and heavy metals increasing since the 1990s. The environmental regulations promulgated by the governments of many countries are tight ening and there is an urgent need which calls the refiners'attention to adopt clean production processes and make clean fuels.     

Preparation of VPO Catalysts and Effect of Zirconium Promoter on the Selective Oxidation of Pentane

1. Introduction The C5 cut, a relatively low-cost hydrocarbon stream in oil refining, has not found adequate use in petrochemical industry (Weissermel and Arpe, 1978). If it is used as liquid-petroleum-gas (LPG) component, the C5 cut is too heavy; while if it is used as gasoline component, the C5 cut is relatively too light. On the contrary, the demand for phthalic and maleic anhydrides is expected to grow at a rate of about 5% per year (Gleaves and Centi, 1993) due to their increasing app…     

Distribution and State of Ni Contaminants on Resid Fluid Catalytic Cracking Catalysts—Characterization by AEM, EPMA, UV-Vis and TPR

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Where is the future of China’s biogas? Review, forecast, and policy implications

This paper discusses the history and present status of different categories of biogas production in China, most of which are classified into rural household production, agriculture-based engineering production, and industry- based engineering production. To evaluate the future biogas production of China, five models including the Hubbert model, the Weibull model, the generalized Weng model, the H–C–Z model, and the Grey model are applied to analyze and forecast the biogas production of each province and the entire country. It is proved that those models which originated from oil research can also be applied to other energy sources. The simulation results reveal that China’s total biogas production is unlikely to keep on a fast-growing trend in the next few years, mainly due to a recent decrease in rural household production, and this greatly differs from the previous goal set by the official department. In addition, China’s biogas production will present a more uneven pattern among regions in the future. This paper will give preliminary explanation for the regional difference of the three biogas sectors and propose some recommendations for instituting corresponding policies and strategies to promote the development of the biogas industry in China.     

Commercial Application of the RAR Sulfur Recovery and Tail Gas Treating Process

The 40kt/a sulfur recovery unit for tail gas treating applying the reduction-absorption-recycling (RAR) technology is aimed at regeneration of the rich amine solution and recovery of sulfur to operate in tandem with the 1.2Mt/a diesel hydrofining unit. The process unit calibration data have revealed that the recovery of total sulfur reaches 99.86%, which is 6.65 percentage points higher than that before application of the RAR technology. The SO2 content in vented tail gas is 0.27 t/d, which is much less than the latest emission standard prescribed by the State. The factors that can affect the unit operation have been analyzed and corresponding measures have been suggested including the necessity to improve the control over the reaction temperature in the tail gas hydrogenation unit.     

Role of Structure and Acidic Nature on Catalytic Behavior of Nickel Supported H-mordenite,H-ZSM-5, and γ–alumina Catalysts

Abstract

Nickel metal was loaded in different percentages (7, 10, and 13% w/w) on different supports (H-mordenite, H-ZSM-5, and γ–alumina). The prepared catalyst samples were tested in cyclohexane conversion using microreactor pulse technique. Structure was followed up by XRD analysis. Chemisorption of tert-butylamine (TBA) was adopted for estimating the number of surface acid sites. It was found that all prepared samples displayed cracking activity, being mostly related to the fraction of acid sites remaining on the surface after coverage with supported Ni atoms. H-mordenite-supported samples exhibited mainly isomerization functionality by showing a larger portion of surface acid sites. H-ZSM-5-supported samples showed higher dehydrogenation activity. Agglomeration seemed to be responsible for lower activity of the sample of higher Ni content. The formed NiOOH phase was suggested to be responsible for increased dehydrogenation activity on H-ZSM-5 samples and increased cracking activity on γ–alumina-supported samples of higher Ni content.