Advanced Materials Research Vols. 807-809

Abstract: A new predictable model of the generation of municipal solid waste (MSW) is established by combining GM(1,1) model and GM(1,N) model. By using GM (1, N) model to do the quantitative analysis on the main factors of the generation of MSW, and using GM (1, 1) model to analyse and predict each factor,the relationship between the various factors and the generation of MSW and the new predictable model of the generation of MSW are obtained. We took the data of Shanghai as the example to establish the combinatorial model. It is analysed that the model's fitting precision and predictable precision are higher. The method has good feasibility and practicability, and provides a quantitative basis for analysing, forecasting and planning management of MSW.

Abstract: For coal-fired power plant boiler flue gas desulfurization wastewater’s actual spraying proposed combination bag house dust while mercury removal process. Experimental study of the coal-fired boiler flue gas spraying chlorine ions and other halogens desulfurization wastewater modified fly ash flue gas mercury performance. Studies showed that desulfurization wastewater fly ash on chloride ion enhanced oxidation of elemental mercury, with the increase in the amount sprayed desulfurization wastewater, flue gas mercury capacity increased. Desulfurization wastewater add another halogen element can promote flue gas mercury performance, the effect of iodine was the most significant, followed by bromine. The desulfurization wastewater as a modified liquid sprayed into the flue modified fly ash, fly ash can improve mercury removal performance, eliminate the need for desulfurization wastewater treatment, cost savings, achieve desulfurization wastewater recycling.

Abstract: Higher nitrogen and phosphorus in the water cause water eutrophication. Nitrogen and phosphorus removal are the primary methods of solving water eutrophication. This paper analyzed the development and key technology from Triple oxidation ditch, UNITANK process to MSBR process for the object of nitrogen and phosphorus removal.

Abstract: There are more advantage for Sulfonated coal such as lower price, materials widely, and stronger ion exchange performance. Sulfonated coal were prepared by huolinhe brown coal and shanxi anthracite as raw material, and the effect of coal quality, ratio of acid to coal on the ion exchange properties of sulfonated coal were studied. Results show that the brown coal is more advantageous to sulfonation reaction, the temperature is 120, sulfonated time is 9 h, and ratio of acid to coal is 5:1. Under the conditions, the ion exchange property of sulfonated coal is best.

Abstract: The ethanol wastewater from one certain chemical plant in Hebei province was treated by the combined process, up-flow anaerobic sludge blanket (UASB) + anoxic/oxic (AN/O) + membrane bioreactor (MBR) + reverse osmosis (RO). The results showed that COD removal rate was 70% when the UASB residence time (HRT) was 48h; and COD removal rate reach 85%, the removal rate of NH3-N was 70%. the removal rate of total phosphorus was 95% when the AN/O residence time (HRT) was 72h; the following COD removal rate was up to 90% when the MBR residence time (HRT) was 12h. The COD of the output water after treatment was lower than 30mg/L, and met the requirement of reused water.

Abstract: To increase the solidifying rate of the existing agent and strength of the solidified layer, the practical effects of the new polymer emulsion (NPE) to solidify the coal powder have been studied in this paper. The practical results show that the solidifying rate of NPE and the solidified layers strength both increase as the NPE concentration increase, and the minimum solidifying time is 10 minutes. The NPE would be widely used in solidifying the coal powder surface and suppressing the dust.

Abstract: The optimum temperature within the reagent injection zone is between 900 and 1150°C for the NO_X reduction by SNCR (selective non-catalytic reduction) in coal-fired utility boiler furnaces. As the load and the fuel property changes, the temperature within the reagent injection zone will bias from the optimum range, which will reduces significantly the de-NO_X efficiency, and consequently the applicability of SNCR technology. An idea to improve the NO_X reduction efficiency of SNCR by regulating the 3-D temperature field in a furnace is proposed in this paper. In order to study the new method, Computational fluid dynamics (CFD) model of a 200 MW multi-fuel tangentially fired boiler have been developed using Fluent 6.3.26 to investigate the three-fuel combustion system of coal, blast furnace gas (BFG), and coke oven gas (COG) with an eddy-dissipation model for simulating the gas-phase combustion, and to examine the NO_X reduction by SNCR using urea-water solution. The current CFD models have been validated by the experimental data obtained from the boiler for case study. The results show that, with the improved coal and air feed method, average residence time of coal particles increases 0.3s, burnout degree of pulverized coal increases 2%, the average temperature at the furnace nose decreases 61K from 1496K to 1435K, the NO emission at the exit (without SNCR) decreases 58 ppm from 528 to 470 ppm, the SNCR NO removal efficiency increases 10% from 36.1 to 46.1%. The numerical simulation results show that this combustion adjustment method based on 3-D temperature field reconstruction measuring system in a 200 MW multi-fuel tangentially fired utility boiler co-firing pulverized coal with BFG and COG is timely and effective to maintain the temperature of reagent injection zone at optimum temperature range and high NO_X removal efficiency of SNCR.

Abstract: The rapid increase in the concentration of CO₂ raises global concern. The latest research indicates that the concentration has reached a new peak of 400^[1] ppm. Effective CO₂ abatement strategies, such as Carbon Capture and Storage (CCS), are of great interest. One common method of CCS is MEA absorption. This paper aims to illustrate post-combustion capture with MEA solvent. The principles, procedures, influencing factors, advantages and drawbacks are discussed to better understand what hinders existing power plants from retrofitting with this technology.

Abstract: The highly ordered mesoporous MCM-41 was synthesized and modified with various content of aluminum (0-15%) using an incipient wetness impregnation technique. The prepared Al modified MCM-41 materials were characterized by XRD, and explored as adsorbents for arsenic(V) removal. Al loading and calcination temperature played significant roles in the absorbents structures and adsorption capacities. The maximal arsenic(V) adsorption capacity of 16.3 mgAs/gAl was obtained when Al loading of 10 wt% and calcination temperature of 400 °C were used.

Abstract: Separation is one of the most important unit operations in biological wastewater treatment. Two commonly employed methods are gravity sedimentation (e.g. secondary clarifier) and membrane filtration (e.g. membrane bioreactor, MBR). Their efficiency at sludge concentrations higher than 10g/L as mixed liquor suspended solids (MLSS) would not meet actual engineering needs any longer. It is of interest to develop a cost-effective process which might pave ways for controlled redistribution of sludge concentration and eventually for reduced excess sludge. This work is to introduce a sub-mili filter as separation media to obtain a target effluent of suspended solids (SS) less than 500mg/L at flux higher than 100L/m²·h and sludge concentration about 20g/L as MLSS. Results show desired effluent SS can be achieved as low as 5mg/L, indicating sub-mili filtration could be an effective supplement to membrane separation and gravity sedimentation for specific applications.