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Hydrocarbon fuel synthesis with renewable energy and captured CO2is a promising option for CCU and an important approach to sustainable energy. Like photosynthesis of plants, the technology of CO2direct captured from atmosphere with CO2utilization would close the carbon cycle thoroughly. Because of the dilute CO2in the atmosphere, the air capture process faces the challenge of high energy penalty. However, integrated with fuel synthesis process, the air capture process can take advantage of the waste heat produced by syngas production process and the transportation of CO2can also be avoided. In this study, a thermodynamic model of the fuel synthesis system is built through energy and exergy analysis. The thermodynamic contribution of three typical CO2capture technologies, moisture swing air capture, high-temperature swing air capture and traditional amine-based flue gas capture, is studied using the model built. Furthermore, by the sensitivity analysis of the critical parameters of the capture, electrolysis and heat exchange process, the influence of each process on the performance of fuel synthesis system is examined and the approach to improve the efficiency of the total system is proposed.

This paper reported the fragmentation behavior of lignite coal particles during coal pyrolysis in fluidized bed reactor at temperature of 300°C,350°C,600°C,650°C. The particles with size of 2-4mm,4-6mm and 7-10mm pyrolyzed under N2atmosphere. The fragments were recovered by hopper, cooled to the ambient temperature and sieved in different ranks. Experimental results show that with the increasing of temperature and initial coal size due to internal overpressure induced by volatiles releasing and thermal stress caused by thermal gradient of coal intra-particles the intensity of fragmentation was enhanced monotonously, the number of fragments increased sharply and the average size of fragments declined.

Since Menggulin reservoir fully been developed in1990, profile control technique is widely used for improving water swept volume. After multiple rounds and large-scales of polymer flooding by materials mixed with sol-gel and Yellow River clay, the formation damage such as depth blockage and stemming become more and more serious.According to statistics, in 2012 there are respectively 10 and 11 water injection wells happened with back flow of profile control agent and wells pressure higher than fracture pressure that without injection. The original reservoir permeability is good, and individual well production has the capacity of 40 to 50m3/d. Yet recently several oil wells almost have fewer even no liquid output due to the blockage and stemming. Estimated by a typical well group,the speed of sol-gel drive increased from 10 m/year to 50~60 m/year, and average water injection pressure were up to 16MPa which almost double original pressure while the only 2MPa pressure corresponding to oil wells. Hence, it show that the severe depth blockage of the formation exactly exit in Menggulin reservoir.

In view of rapid water cut increasing and poor oil recovery with banded distribution with high permeability belt in sandstone reservoir of Huabei Oilfield,the electrical bridge technique for water shut-off is proposed. Based on years practice of vertical wells and similarity in Ohms and Darcys laws,the electrical model involved variable resistors series/parallel instead of reservoir distribution,the arm-bridge circuit combined with signal detection. Then response of the circuit by variable water shut-off could be simulated. The results indicated that,the driving pressure and seepage quantity at mid-low permeability channel could be greatly improved by the strong in-depth water-plugging at high permeability channel (L=20~40m),and the low permeability flowrate increased to a maximum of 55.3%. Then the gel dam in-depth fluid diversion technique was verified by water plugging and circuit simulation. The conclusions provided a valuable guidance for horizontal wells development enhanced.

MCM-41 supported nickel phosphide (Ni2P/MCM-41) was prepared by temperature-programmed reduction of the corresponding phosphate. The catalyst activity for hydrodeoxygenation (HDO), hydrodearomatization (HDA), hydrodenitrogenation (HDN) and hydrodesulfurization (HDS) was investigated in a fixed bed reactor. O-cresol HDO, 1-methylnaphthalene HDA, quinoline HDN, dibenzothiophene HDS and simultaneous HDO, HDA, HDN, HDS were respectively tested at different temperatures with constant pressure (6.0 MPa), liquid hourly space velocity (3.0 h-1), hydrogen-to-oil volume ratio (600:1). The results indicate that Ni2P /MCM-41 catalyst has great performance on HDO, HDA, HDN, HDS in single model compound reactions. O-cresol and DBT are almost completely transformed at 375°C, while 1-methylnaphthalene and quinoline reach the highest conversion at 300°C. In the simultaneous reactions, quinoline shows higher conversion by competitive adsorption on the catalyst hydrogenation sites, leading to conversion decrease of o-cresol, 1-methylnaphthalene and DBT.

pH value is one of the most important factors which affect the nitrogen and phosphorus removal in the wastewater treatment process. The influences of potential of hydrogen on nitrogen and phosphorus removal of wastewater were studied in this study. The results revealed that: (1) faintly acidic environment was conducive to biological phosphorus removal in biochemical reactors with FeCl3, PFS and PAS but not with Al2(SO4)3.On the other hand, synergistic effect between the microorganism and coagulants ( FeCl3, PFS, Al2(SO4)3 and PAS) was confirmed in this study. (2) faintly acidic environment was favorable to the nitrogen removal in biochemical reactors with PFS and PAS while the faintly alkaline environment was conducive to the nitrogen removal with FeCl3 and Al2(SO4)3. And there was no synergistic effect between the microorganism and coagulants.

In this paper, the subcarrier and power allocation problem for the orthogonal frequency division multiplexing (OFDM) cognitive radio network which coexists with the primary network is studied. A cognitive waterfilling (CWF) power allocation algorithm which based upon the classical waterfilling mechanism is proposed for the single SU scenario. As for multi-SU case, we present an efficient joint subcarrier and power allocation algorithm called MS-CWF algorithm. Simulation results show the effectiveness of the proposed CWF and MS-CWF algorithms.

In this paper, the working process mathematical models of in-cylinder of the diesel engine, exhaust turbocharger and intercooler are established, as well as the simulating model using simulation Software GT-POWER. Through parameters modification, we built the Map of efficiency characteristic curve of compressor and turbocharger. Targeted at the turbocharged intercooled diesel engine of YC4F92 type, simulating calculation and experimental verification are conducted. It turned out that the simulating value and experimental value matches well and the maximum error value is not more than 5%, which demonstrated the accuracy and reliability of the established model. The established model can works as a tool for the design and optimization of diesel engine.

By using some types of means such as Optical Microscope (OM), Scanning Electron Microscopy(SEM), the testing of tensile mechanical properties and the testing of friction and wear, the impacts of the Al-5Ti-1B and Al-20Sr modification on the Al-16Si-4Cu-0.5Mg-0.2Mn alloy microstructure, mechanical properties and friction properties are researched. The results turn out that the modification can significantly refine the primary silicon and the eutectic silicon in the alloy, the Al-5Ti-1B mainly refined the primary silicon in the alloy, the Al-20Sr refined the eutectic silicon; the alloy’s effect of refinement after compound modification is better than that in separate metamorphism. Modification can improve the tensile strength and elongation of the alloy: the tensile strength of the alloy has been increased by 65MPa after its compound modification; also the elongation by 0.4%. Modification can improve wear-resisting property of the alloy and also its effect of compound modification is better than that of separate metamorphism. The modification mechanism of Al-5Ti-1B is that Al3Ti and TiB2 belongs to heterogeneous nucleation; while the modification mechanism of Al-20Sr is that the strontium changes the growth pattern of Si phase.

As the first step in coal combustion and gasification, coal devolatilization has significant effect on reaction process. Previous coal devolatilization models have some disadvantages, such as poor flexibility, model complexity, and requirement of characterization parameters. Recently, Sommariva et al. have proposed a multi-step kinetic model of coal devolatilization. This model avoids the disadvantages mentioned above and can predict elemental composition of tar and char. In this paper, the mechanism of this model has been revised for simple application to Chemkin. Revision method is that some reactions are split into more reactions by using one pseudo-intermediate-product to replace several final products. Simulation results show that calculation results from revised mechanism compare quite well with that from original mechanism and have good agreement with experimental data. The revised mechanism is accurate and can be applied to Chemkin very easily, which gives it wide application to simulation of coal pyrolysis, gasification and combustion.

In response to the deposition problem in biomass-fired boiler, inert addictive was tested to inhibit the possibility of coking. The deposition samples collected from final and primary superheater of biomass-fired CFB (circulating fluidized bed) boiler were grinded into fine powder. The inhibitive ability of additive was tested by mixing the deposition sample with different proportions of inhibitor under high temperature. By means of scanning electron microscope (SEM), X-ray diffraction (XRD) and other analytical procedures, the properties of the samples with inhibitor such as microstructure, composition were studied. The inhibitor was also introduced to the industrial biomass CFB boiler to verify its inhibition effect on superheater deposition. Unfortunately, the effect of adding inhibitor in industrial boiler is not certain, though the inhibitor added to the samples is obviously effective in weakening coking in the laboratory scope.

Absorption of carbon dioxide (CO2) by blended diethanolamine (DEA) + 2-amino-2- methyl-1-propanol (AMP) and single DEA solvents were compared using hollow fiber membrane contactor (HFMC). Experimental results showed AMP additive has positive influence to improve CO2 absorption flux and the optimum AMP/DEA mass concentration ratio is between 0.2 and 0.4. Decreasing gas liquid ratio could greatly promote CO2 absorption, and operating temperature has weak effect on CO2 flux. Besides, large CO2 flux can be achieved with high concentration of DEA+0.2AMP solution due to the decrease of liquid phase resistance to mass transfer, but the optimal DEA concentration was recommended to be about 15% for DEA+0.2AMP solution considering the costs of amines in HFMC.

In this study, a commercial activated carbon was assessed as adsorbent for post-combustion CO2 capture. The breakthrough adsorption experiments were conducted in a fixed-bed column with simulated flue gas of 12% CO2. The effects of feed flow rate and adsorption pressure on breakthrough time and CO2 adsorption capacity were evaluated. The column efficiency was introduced to estimate the percentage of the utilization of the bed adsorbent capacity. At a higher flow rate, the breakthrough time, breakthrough capacity and column efficiency decreased. Conversely, increasing adsorption pressure was favorable to CO2 adsorption by the increase in breakthrough time, CO2 adsorption capacity and the column efficiency. During the experiments, temperature changes were detected at three positions inside the column to track the movement of breakthrough front.

Isolation of phenols from the middle oil fraction(170-230°C) of tar produced in the multi-cogeneration system has been investigated for the purpose of recovering valuable pure phenols, such as phenol, cresols, xylenol and ethyl-phenol. Phenolic compounds were separated from the middle oil by liquid-liquid extraction using alkali and sulfuric acid. The yield of phenolic fraction from the middle oil (170-230°C) is up to 37%, which is much higher compared with those of metallurgical coke plants. Chromatography-mass spectrometry was used to analyse phenolic compounds. The result shows that the phenol content is less than 2%, and main compounds are cresol(14%), xylenol(20%) . Phenols of the middle oil fraction(230-280°C) was also analysed, which main contain methyl naphthol(20%).

Modification of polypropylene (PP) by the addition of polyolefin elastomer (POE) and attapulgite (AT) has been investigated. The result have shown that the addition of POE and AT gave PP excellent mechanical properties of improved impact strength and comparable stiffness. The bonding between AT and the matrix was enhanced with the addition of dispersant EBS. AT was an effective nucleating agent for PP crystallization, and finer and more homogeneous spherulites of PP was obtained. In this study, the toughening mechanism of the composites was also discussed.