Advanced Materials Research Vols. 518-523

Abstract: The third-party is responsible to recycle the regenerated resources is the main channel in China. By comparing the operating modes of the third-party recycle, this paper supposes that recycling enterprises should promote the development of regenerated industry based on the platform function of the online system, improve the recovery of the regenerated resources depends on the advantages of the dispersive recycle; and increase the recycle efficiency of the regenerated resources according to flexible management.

Abstract: With government-depth recognition of scientific development and improvement of people’s living environment, treatments of MSW has become one of the key points of environmental protection. Herein, the formation paths of dioxins and heavy metals during the thermal treatment of MSW were presented detailed, the countermeasures including source control, thermal treatment technology and gas and ash terminal-treat for the emissions control were proposed either.

Abstract: Production of alternative diesel fuel has been increasing drastically in many Asian countries. Since the reduction of petroleum production by Organization of Petroleum Exporting Countries (OPEC), the research on alternative fuel for diesel engine has gain interest. The target of this project is to substitute some percentage usage of conventional diesel fuel with waste substance without compromising on engine performance and exhaust emissions. This study has produced two type of alternative fuels. A test fuel consisting 30% of water into diesel fuel with the existence of additive or emulsifier (span 80) is called as DW Emul. Another test fuel which is named as DHW Emul produced by blending 30% of water into a mixture consisting of 20% of waste hydraulic oil and 80% of diesel fuel with the existence of span 80. The engine performance and exhaust emissions of DW Emul and DHW Emul are measured and has been compared with the conventional diesel fuel. A 600cc single cylinder direct injection diesel engine was used. The experiment was conducted at 1500 rpm with variable engine loads. Results show that DHW Emul and DW Emul has higher brake specific fuel consumption (BSFC). However, by considering the total use of diesel fuel contained in DW Emul, the quantity was lower at all loads. The same goes for DHW Emul at low load but deteriorate at high load which show slightly higher compared with of using 100% conventional diesel fuel. DHW Emul has suppressed CO emission that is usually high of using emulsion fuel to the level similar to conventional diesel fuel. NOx and Smoke emissions for DHW Emul are lower than conventional diesel. The use of DHW Emul can give significant reduction of NOx and Smoke emissions without deterioration of CO emission.

Abstract: According to production technology and the analysis of walnut shell filtering media during filtering processing in DaQing oilfield, the main pollution ingredients are crude oil, sulfide, etc. Combined with capacity and characteristics of preventing dirt of walnut shell, compound use different detergents to obtain the better detergent, including 2.10 g NaOH, 3.03 gNa2SiO4• (9 H2O), 0.93 g Na5P3O10, 1.63 g Na2CO3, 3.03 ml OP-10, 11.67 ml HO(CH2CH20)nH, 55 ml water, 3 g LAS at 60°C. Removal rate of pollutants is 98.78%. The agent solves the recycling of walnut shell filtering media, in order to apply for replacement of filter media more economically and reduce ground environment pollution.

Abstract: The co-combustibility of coal and sludge was investigated with thermogravimetric analysis. The results show that the burning process of sludge can be divided into three phases: water evaporation, volatile matter volatilization and combustion, fixed carbon combustion and burning out. The ignition temperature of sludge is only 260 degree centigrade at the beginning of volatile matter combustion. The addition of wet sludge or dried sludge will reduce the burning velocity of coal, and also decrease the ignition temperature. However the blend of coal and sludge has not an obvious stage of the volatile matter volatilization and combustion. The activation energy of the sludge is lower than that of the coal. The addition of wet sludge or dried sludge will decrease the activation energy of the blend fuel, and improve the fire behavior. On the whole, the sludge addition has little influence on the combustion of the coal when the addition ratio is lower than 10%.

Abstract: Housing feeding is scattering in most part of China. The dislocation between the date of getting livestock wastes out and the fertilization date and also a shortage of supervision have been making a serious loss of livestock wastes and be a reason of agricultural non-point source pollution. The collection mode which befits the northern valley of Erhai Lake is proposed by considering the characteristics of rural non-point source pollution and the status of wastes collection and treatment facilities. The conclusion that the decentralized collection should be taken the place of centralized collection is also come to at last.

Abstract: As the increase rate of municipal sewage treatment, the reuse, disposal, and management of sewage sludge generated by wastewater treatment have become an issue of public concern due to the substantial quantity of sludge generated in China. On the basis of summarizing technologies of sludge disposal at home and abroad, the paper sampled and analyzed pH, moisture content, nutrition contents and heavy metal contents in sludge from Tianjin Qingninghou landfill, to assess the possible utilization technologies. The testing results showed that the concentrations of Cu, approximately 1790.97mg•kg^-1, was so high that sludge can not be reused from Dongli wastewater treatment plant, while dredged sediment from Dagu River could be used in co-landfilling, land improvement of neutral and alkaline soil, the production of cement clinker, as well as further dewatered and dried sludge from Jizhuangzi, Xianyang Road and Beichen wastewater treatment plant. In addition, sludge could be used for acid soil improvement and making brick from Jizhuangzi and Beichen, to extend life of the landfill and achieve the goal of sustainable development.

Abstract: This paper is a case of studying the potential benefits for the city of Beijing in China, such as land resources, environment, disposal cost of municipal solid waste (MSW) and so on and assessing and presenting the results of assessing their contributions on resources, environment and economy for Beijing city in 2007.

Abstract: Biogas was generated from cow manure in a experimental 20 m³ reactor with a jet mixing system at a temperature of 35°C. The initial concentration of TS was 5%. Several parameters was investigated to elucidate the variation law of some critical indicators in the experimental biogas systems in batch fermentation process, such as biogas production rate, biogas composition, pH, COD and VFAs concentration. It was found that the biogas production was above 0.3 m³/ kg TS under mesophilic temperature conditions, and the total biogas produced was 108 m³. The methane content in biogas was around 60% after 6 days of fermentation.COD decreased from 26,800mg/L to less than 10,000mg/L, of which 72% was converted to biogas. The concentration of VFAs decreased from 2.27g/L to around 0.8g/L, and value of the pH was stabilized between 7.36 and 7.53 after the 9th day. This anaerobic digestion system had many advantages over other conventional systems,such as stability operation, energy-saving and high substrate utilization rate, which means its application in biogas production is feasible.

Abstract: Based on the thermogravimetric analysis, co-pyrolysis of expandable polystyrene foam plastics (EPS) and three kinds of biomass (bagasse, peanut shell, corncob) were investigated. The result shows that synergistic effects of the co-pyrolysis of EPS/bagasse and EPS/corncob are obvious, but there is no remarkable synergistic effect for the EPS and peanut shell blends. The kinetic analysis indicates that the pyrolysis processes can be described as first order reactions model, a pretty good fitting of experimental data was obtained for all samples. In the EPS and the biomass pyrolysis, respectively， the former can be described as the one first-order reaction model, and the latter can be described as the three consecutive models, while the co-pyrolysis of EPS and biomass needs to be described as the four consecutive models.