Advanced Materials Research Vols. 1010-1012

Abstract: MBBR processes improve reliability, simplify operation and require less space than traditional wastewater treatment systems. The performance of biological membrane carriers is very important to MBBR operating efficiency. Modified HDPE material is more hydrophilic and electropositive. The experiment indicates that: The grafting percent is 3.67% at 40 min exposing time in Acetone-AA-BP system. The outflow COD_Cr and NH₃-N removal efficiency is 87.57~93.12% and 68.82~76.33% respectively in modified HDPE system. The outflow COD_Cr and NH₃-N concentration is content to II series in Discharge standard of water pollutants (DB 11/307-2005).

Abstract: Bio-drying process, degrading part of the easily biodegradable organic fraction contained in waste, produces heat that combined with an adequate airflow-rate, allows the fast evaporation of waste moisture content. Three ventilation methods were used to investigate the effect of bio-drying pretreatment on municipal solid waste (MSW) characteristics (including water content, mass, heating value and the gross energy capacity). The results show that the water content of MSW decreased from 61.5% to minimum 23.7% after 18 days bio-drying, whereas its lower heating value (LHV) increased an average of 168% from 5413 kJ/kg. In the three trials, the highest LHV amounted to 15.8 MJ/kg, which achieved the LHV demand of solid recovery fuel (SRF). In bio-drying process, the average water removal rate was 80.6%. Smaller organic matter degradation led to a great decline of the water content; therefore, the decrease of gross energy capacity of MSW is not significant.

Abstract: An experimental study on the desulfurization system by atomized ammonia injection was conducted in the tail flue of a 300MW CFB boiler. The tests was going under the unit load ranges from 229.5MW to 267MW with ammonia concentration of 5.2~9% and flow at 3.7~9.0 t/h, the gas temperature at 145~149°C, the maximum final desulfurization efficiency is 55.6%, the average removal efficiency at 21% ~ 26%. The ammonia also has an activation function to the CaO in fly ash, which counts 15.7% to 29.8% of the total amount CaO in fly ash.

Abstract: Tubificidae is often used in the wastewater treatment systems to minimize the sludge production. A two-compartment kinetic model was applied to simulate the uptake and release of C, N and P-bearing pollutants by Tubificidae in a sludge reduction system. The nonlinear fitting method was used to calculate the uptake rate constant K₁ and the release rate constant K₂ for TOC, TN and TP, which were 4.983, 25.764, 10.154 and 3.671, 23.683, 9.023, respectively. The model fitted quite well with the collected data, suggesting that the model was applicable. The results showed that Tubificidae activity would increase the C, N and P concentrations in the system, and the specific release rates of C, N and P-bearing pollutants were 4.31 mg COD/g L. hoffmeisteri· d, 0.722 mg TN/g L. hoffmeisteri· d, and 0.14 mg TP/g L. hoffmeisteri· d, respectively. Ammonia nitrogen contributed up to 70.42% of the released nitrogen.

Abstract: Using phytoremediation technique to remove contaminants from soil had become a topic in current research. This article expounded the domestic and oversea research progress of plants on polyploid techniques and was systematically elaborated from many aspects, including the formation of polyploid, induction methods, and application, etc. The direction of phytoremediation is put forward that the biomass and heavy metal accumulation quantity of hyperaccumulators would be raised through polyploid induction.

Abstract: An earthworm-assisted phytoremediation of Cr contaminated soil was conducted to study the performance of different earthworm species in Cr accumulation of Vetiver Grass (vetiveria Zizanioides VG). Two species of earthworm (Eisenia Foelide and Pheretima guillemi Michaelsen) were added in trial. The result showed Vetiveria Zizanioides can absorb great amounts of chromium in soil. The decline rate of Cr was up to 87% and 78% respectively in the tiral of Eisenia Foelide (EF) and Pheretima guillemi Michaelsen(PGM) at 60^th day. As the concentration of Cr gradually increased within 3.3-120mg/kg, the accumulation activity of two groups presented first increase and then decrease and reached maximum 976.7mg/kg and 943.1 mg/kg in root. It began to decrease when the Cr concentration was above 120mg/kg.Vetiveria Zizanioides's accumulation ability differs in root and shoot. It presented root>shoot. With a comparative analysis, PGM has higher accumulation and resistance to Cr at any designed treatments. In the analysis of relation between plants and soils, it was found that there was significant correlation in Cr contents between plants and soils (P<0.05). There was a high retention rate of Vetiveria Zizanioides root to Cr. Retention rate of any treatments adding earthworm were all greater than 87.91%. The biggest value was up to 96.23%. There was no obvious difference between EG and PGM in retention rate.

Abstract: For making timely and correct decisions for emergent pollution emergency of the water environment, combined with fuzzy integrated evaluation method, the model for the evaluation of emergency is established. Qinghe river basin is estimated in 3-level fuzzy integrated evaluation from 6 aspects. The results show that the score of emergent pollution emergency of the water environment of Qinghe river assessment is 3.9273,which close to a good level. The capacity of emergency support and emergency response is superior, and the abilities of emergency prevention, emergency decision-making and emergency recovery are relatively general, which should be completed.Emergent pollution emergency of the water environment is affected by many factors, a multi-target integrated evaluation system should be established. At present, the emergent pollution emergency system of water environment in our country still needs to be improved, the construction of which started relatively late, and the evaluation of which is at the exploration stage. To find the existing problems and shortcomings in emergency system of emergent pollution in water environment, the emergency evaluation index system is established, which improve the water environmental pollution emergency system. However, most of the indicators building the index system are qualitative, which has certain fuzziness when being estimated. Meanwhile it exists certain fuzziness when expressing characterizing attributes of the degree of realization and level of most evaluation indicators, and it is difficult to use specific, accurate data for quantitative description, generally it is expressed by fuzzy degree concepts like ‘Excellent, good, medium, qualified, bad’ and so on. Therefore, the emergent pollution of water environment is estimated by fuzzy integrated evaluation method in this paper.

Abstract: Abstract. In order to reveal the regulating capacity of organic fertilizers on washed soil, pots experiments were carried out. The growth of tomatoes planted on washed soil amended by organic fertilizers were measured. Organic fertilizers can be helpful to improve the plant height, stem diameter, the aerial parts fresh weight, root fresh weight, leaf photosynthetic rates and photosynthesis, and lay a good foundation for the growth of tomatoes. The effect of organic fertilizers is the most significant. Among all the treatments of adding 2.5%, 5%, 10% organic fertilizers, adding 10% organic fertilizers is the best. It can significantly enhance the growth and photosynthesis of tomatoes, and is among the best of these three soil treatments for washed soil.

Abstract: The marine oil and gas transmission pipelines should be washed by phosphoric acid solution before they were used. The washing wastewater, containing high level of phosphorus, was treated by calcium chloride. The response surface method (RSM) based on Box-Behnken was adopted to consider the impact of n (Ca):n (P), pH and reaction temperature on total phosphorus (TP) removal rate. In this work, the Design-Expert 8.0.6 was employed to design and analyze the results. Then, a quadratic polynomial model was built with TP removal rate as the response value. It was shown that the n (Ca):n (P) and pH have a significant effect on TP removal rate. The interaction of pH and temperature is significant. The optimum conditions were X₁=3.40, X₂=10.97, X₃=38.12. In this condition, the predicted value of TP removal rate is 99.9242% while the average removal rate of verification is 99.9365%, which was shown that the predicted value was identical with experiment value.

Abstract: A typical rice field ecosystem as the research object, using the indoor pot experiment to study the three kinds of water driven (shallow layer of continuous irrigation (C), alternating wet and dry (J), and water control mode (G)) on the effect of rice rhizosphere soil denitrification intensity. Effect of changes in soil moisture caused by the three different irrigation patterns on different growth stages of rice on rhizosphere denitrification was comparatively analyzed,referring to the rhizosphere denitrification capacity during different rice growth stage.The results showed that: soil denitrification intensity with different water managements changed significantly, showing C>J>G. And with the growth of plants, under three different water managements, denitrification intensity showed a downward trend. Mature reached to a minimum. All have to be higher than control groups.