Applied Mechanics and Materials Vols. 448-453

Abstract: Because of the large-scale emission of nitrous oxides (NO_x) in recent years, acid rain is still one of the major air pollution problems in China, although SO₂ has been well controlled. And then, the goals for the total emission control of NO_x begin to move forward in the 12th five-year plan, which requires a 10% cut in national NO_x emissions by 2015, relative to the 2010 level, and NO_x emission reduction of coal-fired power plants are still put in a strategic position. Accordingly, it’s of great significance to carry out flue gas denitrification work around the power industry with purposes and plans. In this study, a mixed 0-1 integer nonlinear flue gas denitrification programming model for power system is developed for the first time, which can be used for planning the initial time put into operation of SCR facilities in a region and optimize the allocation of NO_x emission reduction balance, which is significant for generation expansion planning. The model is applied to the power system in Heilongjiang province and the results indicate that the proposed model not only can meet the requirement of flue gas denitrification management, but also can help the coal-fired power plants clear the economic impact of NO_x emission reduction on self-development. This study can provide reference for the decision support of NO_x emission reduction and generation expansion in power industry.

Abstract: The characterization and use in sludge dewatering of a novel bioflocculant M-C11 produced by Klebsiella pneumoniae was investigated. The purified M-C11 was composed of 91.20% sugar, 4.61% protein and 3.91% nucleic acids (w/w). Fourier transform infrared (FT-IR) spectroscopy of purified M-C11 confirmed the presence of carboxyl, hydroxyl, methoxyl and amino groups. The sludge resistance to filtration (SRF) decreased remarkably from 11.64×10¹² m/kg to 4.66×10¹² m/kg under the optimum conditions (pH=6, 3 mL bioflocculant and 4 mL CaCl₂ dosage), after being conditioned with bioflocculant M-C11, which was more efficient than inorganic flocculants. Results showed that M-C11 could serve as a substitute for chemical conditioners and a promising alternative to the sludge treatment industries.

Abstract: In this paper, the ageing degree of recovered asphalt collected from old asphalt mixture is firstly estimated by comparing with virgin asphalt. Then, two kinds of different recycling agents are selected to mix with recovered asphalt. The influence of recycling agent type and content on regenerated asphalt performance is then studied. The results show serious condition of ageing and high viscosity of waste asphalt. As the recycling agent content increasing, the asphaltene and resin content of regenerated asphalt reduced, the aromatics content increased, while the saturate content showed a small increasing. Within this experiment, the penetration and the ductility of regenerated asphalt increased, while the softening point reduced as the recycling agent content increasing.

Abstract: Activated carbons were prepared with Baijiu vinasse in this study. The response surface method was used to optimize the process parameters of NaOH solution boiling treatment to extract the protein in Baijiu vinasse. Ascertaining the optimum conditions that NaOH solution concentration is 2.5mol/L, treating time is 2hours and solid-liquid ratio is 1:4. So the protein retention rate is 1.116%.The methods of ZnCl₂ chemical activation and high temperature calcination activation were used to prepare activated carbons. Under the optimum conditions of ZnCl₂ concentration 50%, solid-liquid ratio 1:2, calcination time 120min, calcination temperature 600°C, the methylene blue adsorption reaches to 208mg/g.

Abstract: The study investigated the amount of mulching plastic film residue in corn¡¢potato and vegetable fields in Inner Mongolia Autonomous Region. The result shows that there has been a very serious pollution, and the average amount of residue of mulching plastic film remained in the farmland of Inner Mongolia is 36.3kg/hm². The average amount of residue of mulching plastic film remained in the corn field soils is 56.25 kg/hm², the potato fields were38.7kg/hm², the vegetable fields were 25.05kg/hm². The results also showed that more than 73% residual film remains in the 0 ~ 10cm plow layer, and the amount of plastic film residue depends on duration of utilization of mulching plastic film, and the longer the duration of utilization, the more plastic film residue is left in the field.

Abstract: With the growing amount of the chemical fertilizer consumption and agricultural wastes, non-point pollution of agriculture has been one of the problems threatening world crop production, especially considering the urgency of climate change. In this paper, a review of the research of biochar, pyroligneous acid and organic fertilizer mixture is given. And agronomic and environmental benefits that can potentially be derived from the application of this soil amendment in soils are discussed.

Abstract: Baijiu vinasse was used as the protein source to produce protein foaming agent. The hydrolysis conditions were optimized. The results show that the optimal conditions are: for every 20 g of baijiu vinasse, 1 g CaO and 80 mL water are add, the reaction temperature is 80°C and reaction time is 2 h. Hydrolyzed twice under the optimal conditions, the protein extraction rate can reach 30.5%. After the hydrolyzation, supernatant was collected, neutralized and condensed to 3% protein content as protein foaming agent. Foam properties were determined by Ross-Miles meter. The foamability is 172 mm, and foam stability is 160 mm, which shows huge potential for application.

Abstract: Wastewater treatment plants produced large amounts of municipal dewatered sewage sludge with about 80wt% moisture content. High moisture content is the bottleneck of sludge treatment and disposal. Hydrothermal treatment could economically disrupt sludge cells, release bound water and finally improve sludge dewaterability instead of thermal drying technology with high energy consumption. In this paper, hydrothermal treatment experiments were carried out and the combustion performance of the original sewage sludge and the hydrothermal treatment sewage sludge was analyzed to verify the possibility of burning after sludge hydrothermal treatment. The results show that the optimal reaction temperature, initial moisture content, pressure and time are 170°C, 87wt%, 0.9MPa and 40min, respectively, obtaining a final moisture content lower than 50wt% by centrifugation. Total Organic Carbon (TOC) results show that higher temperature and pressure, as well as longer reaction time are of benefit to the hydrothermal treatment of the municipal sewage sludge. Furthermore, Thermal Gravimetric Analysis (TGA) of the original sewage sludge and the hydrothermal treatment sewage sludge shows that a hydrothermal treatment can improve the combustion performance of the sludge, which is beneficial to the subsequent incineration process.

Abstract: The main focus of this paper is concerned with the production and properties of refuse derived fuel 5 (RDF-5) for use in energy from waste technologies. The analysis was performed using feedstocks made up of residues from a range of mechanical biological treatment (MBT) plants and crude oil sludge. The RDF-5 was composed of crude oil sludge and mechanical biological waste treatment (MBWT). The ratios of MBWT to crude oil sludge were 5:95, 10:90, 15:85 and 20:80 respectively. The physical and thermal characteristics of RDF-5 were examined. This was further investigated in the context of the parameters required during production and the properties of RDF-5. RDF-5 was produced using a screw compactor. Analysis of the optimal mixing ratios between the crude oil sludge and MBWT were undertaken by testing the thermal value based on ASTM D 240 moisture contents was based on ASTM D 3173, ash was based on ASTM D 3174, and density was based on ASTM E 75 respectively. The results showed that the optimal ratios of MBWT to crude oil sludge were 15:85 and 20:80 have feasibility to produce the RDF-5. Because of the ratios of 15:85 and 20:80 have a high value 10,831 kcal/kg and 11,260 kcal/kg, the percentages of moisture were 2.73% and 5.93% and the density values were 750 kg/m³ and 806 kg/m³ respectively (RDF-5 has a high heating value (HHV > 5,000 kcal/kg), with the percentage of moisture content not exceeding 10 percent and the density value (D 600 kg/m³) according to production of solid fuels standards). The ash values were 5.10% and 4.74% respectively. Comparing the energy production costs between RDF-5 and other fuels used in Thailand we found that the production costs of RDF-5 were 0.014 /MJ and 0.013 /MJ which are comparable to that of paddy husk and much cheaper than those of fuel lignite and bituminous. This preliminary evaluation reveals that the recovery of energy through RDF-5 production from MBWT with crude oil sludge is cost attractive and it should be considered as a feasible option for utilizing energy from MBWT with crude oil sludge.

Abstract: With the problem of shortage of resources and environmental degradation increasingly, to establish a recyclingoriented sustainable development of society or a reasonable treatment of waste household appliances is necessary. It has become a worldwide consensus and issues of mutual interests. This paper,based on the status of home appliance recycling , focuses on the Qingdao Municipal waste home appliances recycling system. This paper combines the theoretical knowledge about waste home appliances recycling in the domestic and abroad studies to study recycling enterprises in Qingdao in recent years. The implementation of waste electrical and electronic products reverse logistics exploration, based on the reality of Qingdao , waste home appliances recycling, foreign experience, comprehensive analysis and research, to study Qingdao's home appliance recycling management system, and put forward recommendations for the rationalization to improve the efficiency of home appliances recycling management system.