Advanced Materials Research Vols. 1008-1009

Abstract: According to analysis of the gas hydrate cage and structure of the inhibitor and simulation of molecular dynamics, the interaction between GHI1 and hydrates was discussed. The structure analysis indicated the side group of PVP can insert into the open hydrate cage, and force the hydrate growing along the polymer chain, which results in a large space resistance and inhibits gas hydrate agglomerating. The results of MD simulation show GHI1 can damage the surface cage in hydrate lattice; the hydrogen and oxygen in GHI1 can form hydrogen bonds respectively with oxygen and hydrogen in hydrates, which makes the surface molecules of the cages unstable and distorts the cages; Synergist diethylene glycol ether increases strength and range of length of hydrogen bond.

Abstract: Co-pyrolysis characteristics of low rank coal (LRC) and enteromorpha (EN) in different proportins were studied in a dry distillation equipment. The results show that he maximum tar yiled of blends was 11.39% with a EN ration of 30%, which increased by 28.61% compared to LRC pyrolysis alone. In the co-pyrolysis tar ,the alkanes’ content was 48.66% and the phenolic was 9.12%, which was significantly higher than the content of the corresponding components of the original tar. The H/C ratio was increased by 9.87%. It indicated the pyrolysis tar became lighter on some degree. While the contents of CH₄ and H₂ in the pyrolysis gas were increased. SEM analysis showed the surface of co-pyrolysis semi-coke became rough and formed obvious center cracks. The heat value of co-pyrolysis semi-coke was higher than that of semi-coke from LRC.

Abstract: Thermal recovery technology are widely used to enhance heavy oil recovery, the four most important of which are thermal modification, sub-critical water modification, catalytic modification and catalytic modification with hydrogen donor. These four kinds of technologies previously were studied separately, which were not systematically integrated together. This paper used high-temperature and high-pressure reactor to simulate heavy oil’s thermal recovery in static condition. By studying basic properties and structural parameters changed of four kinds of thermal recovery technologies, we have drawn the conclusion that The quality of crude oil dropped only by the use of TM, and The degrees of improvement were as follows: CMH> CM> SWM . H/C (Atomic ratio), f_A, f_N, f_P and CI were important parameters, which could explain the extent of condensation and condensation direction. Long chain sulfur compound break down into small molecules, damaging the colloidal structure of heavy oil, improving the quality of heavy irreversible.

Abstract: The Mg-Al mixed oxides were deposited on the MCM-41 via the coprecipitation followed by thermal decomposition and characterized by many techniques. In the transesterification of glycerol (GL) with dimethyl carbonate (DMC), the resulting supported catalysts exhibited much higher catalytic performance than the pure Mg-Al mixed oxides, which was ascribed to the increased basicity. Under the optimal reaction conditions, the obtained data showed that at DMC/glycerol molar ratio of 3:1, catalyst loading of 0.3 g and reaction temperature of 373 K, the glycerol conversion and glycerol carbonate yield from the process was 98.7 % and 92.5%, respectively.

Abstract: Two ashless triazine derivatives, 2,4-bi-amido-6-(O,O′-di-i-octhyl dithiophosphate)- 1,3,5 - triazine were synthesized. Their tribological properties as lubricating oil additives compared with ZDDP in hydrogenated oil were evaluated using a four-ball tester. The results show that these triazine derivatives possess extreme pressure capacity, and they can improve antiwear and friction-reducing performance of base stock than that of ZDDP. Their tribological performance is corresponding to the amide. The elements chemical states of the worn surface were estimated through X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM). The results show that a protective film containing sulphide, phosphate and some organic nitrogen compounds was formed on the worn surface during the lubrication process, and the film possesses extreme pressure and antiwear properties.

Abstract: The inorganic species are highly volatile, released during thermal conversion process and especially at high pressure combustion leads to several problems of fouling, slagging and corrosion when they reach the colder part of plant. The comprehensive knowledge of release alkali species Na-,K-,Cl and S-species is required prior to carry out experiment. Therefore thermodynamic equilibrium calculations were performed by Fact Sage 5.2 and simulated the combustion environment at elevated pressure. Three soft Pakistani coal such as Lakhra (Vad < 41.44%), Thar (Vad < 42.02%) and Sor-range ((Vad < 21.11%) belong to Lignite and sub-bituminous coal were selected and releasing order was calculated by plotting mole fraction of each species VS pressure (5 to 15bar ) at 1000°C. On the basis of predicted releasing order the SO₂ can be predicted most stable species under combustion at elevated pressure. The high released amount of SO2, H2S, NaCl, KCl and HCl was predicted for LKH, THC and SRC at 5 and 15 bar pressure and 1000°C temperature.Comparing with high pressure the predicted released of SO₂ was found higher than H₂S, NaCl, KCl and HCl at 5 bar pressure while the released of H₂S was observed lower than SO₂, NaCl, KCl and HCl at 15 bar pressure during combustion process. The above available predicted information is valuable for hot gas cleaning technology.

Abstract: Supersonic swirling separator has been developed for natural gas dehydration in recent years. Referred to quantities of literature, the working principle and advantages of supersonic swriling separator are discussed. The paper also reviews the research progress of supersonic swirling separator both in developed countries and China in detail. Firstly, the separation technology process from Twister-I to improved Twister-II, and 3s technology in Russia, which comes from aviation technology are reviewed. Secondly, the design of nozzle and cyclone device which are important components for a separator, the simulation of characteristics of gas-fluid two phase flow, and the acquisition of various types of separators and indoor experiments since the project set up in 2003 in China have been introduced. Although there is a considerably long way to go before the industrial application, great achievements such as patents have been made and abundant experimental data and valuable conclusions have been accumulated for further research. Through comparisons and analyses of all these separators, the paper points out both their advantages and disadvantages and the focus of research in the future.

Abstract: CuO/γ-Al₂O₃ catalyst was used to deal with the waste leachate in CWAO technology of, and the SEM and TEM characterization showed: active component in the surface of the carrier distribution is uniform; In CWAO process, six factors, based on the COD_Cr removal rate and turbidity removal rate, the biggest impact factor is reaction temperature, and the influence factors of the top three were reaction temperature, catalyst dosage and reaction time. The influence factors of those in the bottom three are influent water pH, oxygen partial pressure, stirring intensity, and three factors of influence on the strength is close. Optimizing operation process, in order: reaction temperature of 200 °C, catalyst dosage of 1.5 g, oxygen partial pressure of 2.0 MPa, stirring intensity 800 rpm, influent water pH of 7.0, the reaction time of 70 min.

Abstract: The electronic properties of Mn-doped Fe₂O₃ and the adsorption of CO on Mn-doped Fe₂O₃ were investigated using density functional theory (DFT) calculations. Mn doping Fe₂O₃ is endothermic process, and high-folded doping is easier than lower-folded doping. Mn-doping changes the conduction and valence band of Fe₂O₃ (104) more obviously than Co-doping. Energy separation between CO molecule and oxygen carrier suggests that electron transfering between CO and high-folded doping surface is easier than between CO and any other low-folded doping surfaces. Then, CO adsorptions on different sites of Mn-doped Fe₂O₃ were further investigated, which shows that Mn decreases the interaction between CO and the surface except for Mn_7f-doped Fe₂O₃ (104). Results promote the fundamental understanding of such metal-doped oxide surface for further application.

Abstract: Natural gas storages in salt caverns are receiving an increasingly important role in energy storage system of many countries. This study focuses on analyzing the consequence of jet fire associated with natural gas storages in salt caverns. A widely used software, ALOHA, was adopted as simulation tool. The reliability of ALOHA was validated by comparing the simulated results with the field data observed in real accidents and the values calculated by a simple model presented in a previous study. The China's first natural gas storage in salt cavern, Jintan natural gas storage, was selected for case study. The case study reveals that the hazard distance of jet fire decreased with the increase of pipeline length, as well as the decrease of pipeline diameter and operating pressure.