Advanced Materials Research Vols. 610-613

Abstract: In this research, the raw water presenting turbidity was sampled to simulate the change of the water quality. A barrier board was used to extend the flowing route and the level change of the overflow; carry out the pre-treatment of high-turbidity raw water. Particle detention time and the average flowing speed analyzed as well for comparing the removal effect with that in the physical field. The particle detention time is as follows: At 4-141 min, the operating time can be shortened; when this is less than 90 min, the effluent still can maintain a 50-88% turbidity removal rate and the water quality of the effluent can even drop to 530 NTU. During the test, most of the average flowing speed was within the operating scope of the rectangular Sedimentation Basin for which the removal rate was 61%-93% and the effluent turbidity was below 1,000 NTU and even up to the optimal 380 NTU. A total of 3 items meet the operating requirements of the Inclinometer Sedimentation Basin, presenting a 54%-72% removal rate and 1,000-1,650 NTU of effluent turbidity; and one item exceeds the operating requirements of the Inclinometer Sedimentation Basin, presenting a lowered 1,900 NTU of effluent turbidity from 3,800 NTU and a 50% removal rate. Large-size particles exist in the high-turbidity raw water, which tends to settle under the gravity effect during after a long-route flowing journey. For example, the turbidity of the influent is 4,300-5,300 NTU which was reduced to 920-750 NTU after the pre-treatment experiment presenting a 79-86% or higher removal rate.

Abstract: Huadian oil shale and its spent char were selected to explore the adsorption properties of oil shale and oil shale char. A bench-scale adsorption system was established for capturing hydrogen sulfide in this test. What’s more, the nitrogen adsorption isotherms test was made in automatic and rapid specific surface-area-analyzer of American’s Gemini2380, which found the adsorption curve and desorption loop of the modified oil shale and oil shale char. Meanwhile, the experiment calculated and analyzed the specific surface area and pore size distribution of samples with BJH theory. The result shows that the adsorption capacity of oil shale char is greater than oil shale. The rougher the pore structure of the adsorbent samples the greater the pore volume, the larger the specific surface area, the better the adsorption effect of H2S.

Abstract: The preparation conditions of modified talcum powder were investigated by discuss the effects of nitric acid mass concentration, nitric acid soak temperature, roasting temperature and roasting time on adsorption properties of methylene blue by talcum powder. Methylene blue dye, as target pollutant, exhibits difficult biochemical degradable characters. The adsorption isotherm of adsorption process was discussed by using the Langmuir isotherm model and Freundlich isotherms model. The results show that the rate of adsorption of methylene blue decreased with the increasing of roasting temperatures and nitric acid soak temperature of modificated talcum powder. The adsorption value of methylene blue of the modified talcum powder increased gradually，then decreased with the increase of roasting time. Compare with the unmodified talcum powder，the adsorption value of methylene blue of the modified talcum powder decreased when roasting temperature and roasting time is too high. With the nitric acid mass concentration increasing, the adsorption of methylene blue on the modified talcum powder increased. It is found that the adsorptive ability of modified talcum powder by HNO3 is higher than original talcum powder. The best talcum powder modified preparation condition is that nitric acid mass concentration 50%, the nitric acid soaks temperature 40°C, calcined temperature 200°C for 120 mins. The removal rate of methylene blue is 84.6% under these preparation conditions. The experimental date fitted very well with the Langmuir isotherms model.

Abstract: The distribution regularity of organic concentration in treatment of wastewater by multi-flora bioreactor was investigated, and the correlation of the distribution regularity with sludge loading and specific oxygen uptake rate and microbial phase was analyzed. The experimental date show that, organic concentration in the reactor are uneven distribution trends, organic concentration are higher in the reactor bottom and bottom left, along the airflow direction, organic concentration are lower in the reactor left and upper part, and changes of organic concentration with sludge loading and specific oxygen uptake rate and microbial phase have some relevance.

Abstract: A2N is two-sludge system, by using the method that first bringing up the cultivation of denitrifying phosphorus removing bacteria (DPB) and nitrification biofilm separately then connecting them, which can start up A2N system successfully. Nitrification biofilm was cultivated in a sequencing batch reactor (SBR). After 30 days, NH4+-N effluent concentration steadily stayed below 0.5mg·L-1.In another SBR, the activated sludge for the enrichment of DPB is from the anaerobic tank, which was firstly operated under anaerobic/aerobic (A/O) condition. After 20 days, PAOs was successfully enriched. Then, the activated sludge was conducted under anaerobic/anoxic/aerobic (A/A/O) condition, maintaining the anaerobic time, gradually increased anoxic time and induced aerobic time. After 30 days DPB was successfully enriched, two phases totally take 50 days. The removal efficiency of total nitrogen and phosphorus are above 85 % and 95 %, so that A2N system was started up successfully.

Abstract: Complex microbial inoculants are highly effective compound bacteria which are widely used in the removal of pollutants, such as organic matter, nitrogen and phosphorus in the paper, printing and dyeing, petroleum and high-salt wastewater. The development of complex microbial inoculants was introduced in this paper, especially their application and influence factors in wastewater treatment. Finally we put forward current problems and development prospects of complex microbial inoculants.

Abstract: This paper analyzes the active coke FGD fundamental principles, structures and current applying situations, and calculates the initial investment active coke FGD and limestone-gypsum FGD. Moreover, it calculates the operating cost by raw material price and products price in China, and compares the initial investment cost and operating cost of the two FGD technologies in different usage period. This paper concludes that the high investment cost limits the wide application of active coke FGD, it can only be applied in some projects need sulfuric acid.

Abstract: To ensure the effectiveness of the pollution control policy and long-lasting, and provide the rationalization recommendations and quantification of the results for sewage and regulators, this paper gives regional sewage’s fuzzy comprehensive evaluation model and solution algorithm, then build the game model on sewage and treatment, and this problem is solved with Nash equilibrium theory. Finally, the example illustrates the model’s effectiveness and operability.

Abstract: Secondary atmospheric pollutions may result from wet flue gas desulfurization (WFGD) systems caused by the reduction of Hg²⁺ to Hg⁰ and lead to a damping of the co-benefit mercury removal efficiency by WFGD systems. The effects of the operating conditions, which included the pH, temperature, and oxygen concentrations, on Hg⁰ re-emission inhibition efficiency by DTCR from WFGD liquors was carried out. The established data reflected an outstanding performance on the Hg⁰ re-emission inhibition from the simulated WFGD liquors by adding DTCR. Our data suggested that a concentration of 0.0005% (v/v) was enough for Hg⁰ re-emission inhibition in the simulated WFGD liquors. The results also indicated that the Hg⁰ re-emission inhibition efficiency by adding DTCR decreased as the operational temperatures increased and the Hg⁰ re-emission inhibition efficiency increased as pH values and the oxygen concentration in the flue gas increased. The present findings could be valuable for industrial application of DTCR as a precipitant for stabilizing dissolved Hg²⁺ to prevent re-emission of Hg⁰ in WFGD solutions.

Abstract: Compared microwave-Fenton with Fenton in catalytic oxidation process of Chinese traditional medicine wastewater. The speed of chemical reactions could be improved for more than 10 times by microwave-assisted catalysis. Under microwave irradiation, most of the CODCr removal is concentrated in less than 30s. Radiation power of the microwave affect the removal rate of CODCr, and the best power is related with the water quality.