Advanced Materials Research Vols. 518-523

Abstract: Re-processing of aged refuse with particle size of 100mm, heating value above 3000kcal/kg above, chlorine content of about 0.13% was added into cement kiln as alternative fuels using screw conveyor. The results show that: except for NOx, emission rate and concentrations of TSPs, HCl, HF, SO2, CO from cement kiln flue gas were increased and volatized significantly after adding alternative fuels. Dosage of 2t/h of alternative fuels affected little on kiln system, so, main process parameters were normal and no more substantial fluctuations, but, the amount of feeding coal at calciner were adjusted more frequently. Element of S in hot raw material into the kiln seemed no significant changes while K and Cl content was significantly increased within the manageable range. Compressive strength, flexural strength, water demand for normal consistency, surface area of clinker all reduced when using alternative fuels, initial setting time and final setting time were increased compared with clinker saturation. Adding alternative fuels saving of coal, but the actual effect of alternative fuel was less than theoretical results, indicating that intermittent feeding mode was not desirable.

Abstract: Biodiesel was made from waste cooking oil via acid catalyst in order to eliminate the waste cooking oil pollution and realize the health of waste oil use. The optimum conditions of biodiesel made from waste cooking oil, effect of reaction time, alcohol-oil ratio and catalyst dosage to the biodiesel conversion were explored by using orthogonal experiment design. The results showed that the conversion of biodiesel is 95.2% under the conditions of the reaction time is 2h, the alcohol-oil ratio is 6:1, the catalyst dosage is 1.5%, and the influence factors can be arranged as follows: reaction time > catalyst dosage > alcohol-oil ratio.

Abstract: Calcium carbide waste paste is highly concentrated and viscous, rich in calcium, and has a great comprehensive utilization potential. Comprehensive utilization process based on high-pressure pipeline transportation is the best choice for use of calcium carbide waste. But the theory of pipeline transportation of the paste has rarely been reported. Industrial-scale transportation experiments with diameter of 75mm, 100mm, and 125mm were conducted, respectively. The results show that the pipe pressure is linearly distributed along the pipeline, but it is piecewise linear. The pipe pressure in the front end drops faster than that in the back end of the pipeline. The pipe pressure is proportional to the flow rate of calcium carbide paste. The delivery resistance increases greatly as the pipe diameter decreases at the same flow rate.

Abstract: The article is based on the survey of rare earth enterprises in Baotou region, Inner Mongolia, analyzes the sorts of rare earth-containing waste produced in rare earth production and their environmental impact. The main sorts of rare earth-containing waste include: low-grade ore generated in the mining sector, tailings from mineral concentrating; water-soaked residue generated in smelting and separating sectors, and solid waste from functional material producing sectors. The low-grade ore has a certain degree of radioactivity, if the economic and technological conditions allowed it also can be used to produce rare-earth. Tailings from mineral concentrating, in addition to radioactivity, it also produces environment pollution to atmosphere, soil and water. However, these tailings are not waste, but the second rare earth mine. Water-soaked residue is radioactive hazardous waste, now stored in line with disposal regulations. Solid wastes from functional materials producing have been recycled and have less impact on the environment.

Abstract: The purpose of this paper is to review the current status of the recycling technologies of spent LIBs (LIBs) based on LiCoO2 system, including the structure and components of the LIBs, the recycling processes from spent LIBs, the problems and prospect of the studies of the recycling technologies have been put forward. Furthermore, the necessity of developing new recycling technologies and processes for lithium-ion power batteries, our research and technical approach are also demonstrated.

Abstract: An integrated and three-dimensional anoxic-aerobic (A/O) process is put forward. The novel A/O process is used to treat printing and dyeing wastewater with concentrated sludge of sludge concentration tank as inoculated sludge. The experiment studies the sludge properties during startup of the A/O process. The results show that the inoculated sludge has completely adapted the quality of the wastewater after operation of 54 d. The average MLSS of A tank and O tank reach 7.26 g/L and 3.69 g/L at the end of the last stage, respectively. The ratios of MLVSS to MLSS in A/O reactor are stable at 0.63 - 0.75. And the sedimentation velocity of sludge has a large-scale promotion and reaches 34.2 m/h in A tank and 25 m/h in O tank, respectively. Simultaneously, the novel A/O reactor has high biodegradability for pollutants with COD_cr removal efficiency of about 70%. The results indicate that the integrated A/O process will be a better method to treat printing and dyeing wastewater.

Abstract: With rapid increasing of the vehicle population of China, The treatment of End-of-life Vehicle (ELV) becomes a serious social problem. Because the situation of ELV, labor cost and the condition of facilities of China are different from the developed countries, the technologies and the recycling process used by the developed countries can not be simply imported to China without any change. In this paper, the recycling processes of the developed counties are analyzed firstly. And then, the shortage and the advantage of the Chinese recycling factories are discussed. According to it, a scheme of ELV recycling process is presented. And three value analyzing models are illustrated which include: (1) model of ELV to raw materials; (2) model of intermediate scrap to product; (3) model of remanufacturing. In the end, the facilities used for EVL recycling factories based on this process are discussed too.

Abstract: An experimental system of rotating spray drying for cleaning the waste incineration flue gas has been set up on account of the particular fact, that the flue gas quantity is small and contains relatively little SO₂,but relatively much HCl. The influence, of the main parameters which could be control during design and operation, on the efficiency of desulphurization and dechlorination has been tested determined. It was showed that this method resulted in higher dechlorination efficiency and lower desulphurization efficiency. Nevertheless, considering the particularities of the waste incineration flue gas, the discharged flue gas which had been cleaned by this method can meet the restrictive demands of discharging standard of SO₂, and at the same time can warrant a higher efficiency of dechlorination. The efficiency of flue gas cleaning can be enhanced by increasing stoichiometric ratio, by injecting more water, by increasing the rotating speed of atomizer and by decreasing flue gas velocity. The efficiency of desulphurization and dechlorination could reach 78％ and 90％ at stoichiometric ratio 1.8, the amount of injection water 15L/h, rotating speed of atomizer 13500r/min and flue gas velocity 0.7m/s.

Abstract: The injury medical waste is the most serious infectious, which serious impact on human health and environmental issues. There are many hidden dangers in the injury medical waste processing, particularly in small and medium-sized hospitals. The current situation, classify and hazard are analysed, as well as problems and difficulties in injury medical waste disposal. The disposal mechods and countermeasures are put forward to dispose the injury medical waste for small and medium-sized hospitals. The research has certain practical significance for injury medical waste disposal.

Abstract: Incineration is an effective way for amega-city to dispose of its substantial Municipal Solid Waste(MSW) in China. But more than 20% of the waste (by weight) will retain in combustor ash, producing a great amount of ash. How to deal with the incineration ash has become a critical problem to the city developing. By the simple analysis of the physical and chemical properties of the ash, and to basis of the beneficial use of municipal waste combustion ash in some countries, the ways of the resource utilization of the bottom ash mainly are discussed in the paper. In addition, engineering and environmental requirements for ash utilization are also analyzed.