Papers by Author: Xing Bin Sun

Abstract: The effects of pulsed white light, input voltage, biological load, pH and turbidity on inactivation of Staphylococcus aureus in drinking water were studied. The results showed that the effect of pulsed white light on the inactivation of Staphylococcus aureus in drinking water was very significant. The concentration of S. aureus reduced to 1.0×101cfu/ml as the pulsed white light flashed for 8 times when the input voltage was 3000v. The inactivation increased with the plus of input voltage, and decreased with the added of biological load. The inactivation kept all most the same when pH is 5.0~9.0, and the effect of turbidity was not obvious when the turbidity was 5~25.

Abstract: In this paper, E. coli as experimental subjects ，by changing the input voltage, bacterial concentration, turbidity and pH to study the impact that the use intense white light on the inactivation of E. coli in medium surface. The results showed that: light pulses had a strong effect on lethal E. coli, with the input voltage increasing, the inactivation rate increased. The input voltage is 2500v as an appropriate experimental condition, that satisfy both conservation of energy and a better inactivation .The inactivation rate and the logarithm of livability of E. coli rising with the bacterial concentration increasing, when the light flashes six times, the medium surface almost be killed. Turbidity affect to the inactivation of E. coli, with the turbidity increasing, the effect of the inactivation gradually weakened. When ph was changed, the impact of pulsed light on E. coli inactivation was less .The effect of inactivation achieve the best level when pH was 6.

Abstract: In this paper, One-step pyrolysis process for the recovery of mercury and zinc from spent zinc–manganese batteries is proposed. Laboratory tests were performed to remove mercury and zinc from spent batteries and recover them. Correctitude test were used to analyze the effect of three factors: temperature, weight and time on the removing and recovery efficiency of zinc. In this research, temperature is dominant factor, weight and time are subordinate. After removing mercury, higher temperature could assure the removing efficiency of mercury above 99.9% at the same time of removing zinc. Under 0.02 MPa, efficiency of removing and recycling of zinc were investigated. The removing efficiency is 94.2% at 950 °C and 96.2% at 1000 °C. When the heated time is 1.5 h, the removing efficiency is 95.6%, which reach the aim 95.0%. With the increase of sample weight, the necessary heated time could be kept within 2.5 h without the loss of removing efficiency. The recycling efficiency of zinc could approach 75%. The content of zinc is above 99.0% in condensed zinc product. After being treated, the residue mass is about 40% of sample.

Abstract: In order to investigate low-temperature influence on the SBR process and sludge bulking, the SBR process pollutants removal effect was studied with normal and low temperature. The experimental results showed that the effluent water quality was better with temperature 22~24°C and DO 2mg/L. During this period, sludge bulking did not happen and the SVI was stable for 30d at the range of 60~80mL/g. The sludge settlement became worse when the temperature sharply dropped to 13~15°C and DO concentration was unchanged, the SVI was sharply increased to 240~270mL/g from 60~80mL/g in several cycles, and it was in the state of sludge bulking for 60d. The system denitrification effect was almost lost and the nitrification effect had been seriously affected. When the temperature returned to normal, the nitrification effect was gradually improved. The effluent water was clear and the SVI returned gradually, but the SVI eventually maintained at 150mL/g without retune to previous range.

Abstract: Because of the poor phosphorus removal of nature zeolite, the best modification method was prepared as follows : First, natural zeolite was soaked in 1mol/L NaOH solution on dynamic condition at 35°C for 1 hour. After washed with deionied water, it was soaked in 20% MgCl2 solution on dynamic condition at 35°C for 48h, then was roasted at 500°C in a muffle furnace for 3h and in the end cooled to normal temperature.Based on this, the capacity of the modified zeolites was studied under different conditions of contact time, dosage and temperature in order to examine dephophorization ability of modified zeolite. The results from batch experiment suggest that the modified zeolite has a more P sorption capacity possibly due to the hydrated magnesium on or in the modified zeolite.

Abstract: Zeolite is a kind of normal adsorber. Unfortunately the adsorption capacity of natural zeolite is low, it must be activated on behalf of reaching a higher adsorption capacity. On this condition, removal of phosphorus through modifying zeolite has been studied in lab scale through using a mechanically stirred batch system. The results showed that the adsorption isotherm of modified zeolite conformed to Freundlich model and the rate of adsorption conformed to Banerm equation.

Abstract: Chironomus kiiensis larvae which cannot be exterminated by conventional disinfection process propagates prolifically in eutrophic water body, and it therefore turns to be a potential problem encountered in drinking water quality. In order to tackle this problem, a pilot-scale study of removal effect on Chironomus kiiensis larvae with chlorine dioxide in a waterworks is performed. The experiment results showed that Chironomus kiiensis larvae can be effectively removed from water by 0.55 mg/L chlorine dioxide pre-oxidation combined with the conventional drinking water treatment process. Higher oxidizability and molecular state of chlorine dioxide in water is the key to the inactivation of Chironomus kiiensis larvae. The chlorite, disinfection by-products (DBPs) of chlorine dioxide, is stable at 0.217 mg/L, which is lower than that critical value of the WHO. Ames test revealed that the mutagenicity was reduced by chlorine dioxide with respect to prechlorine. The propagation of Chironomus kiiensis larvae can be inactivated effectively and safely by chlorine dioxide pre-oxidation.

Abstract: Chironomus kiiensis larvae which cannot be exterminated by conventional disinfection process propagates prolifically in eutrophic water body, and it therefore turns to be a potential problem encountered in drinking water quality. In this work, the quantitative experimental studies were carried out on removal of Chironomus kiiensis larvae in raw water by coagulation-sedimentation process. The coagulation jar test showed that the Chironomus kiiensis larvae could be partially removed from water by coagulation-sedimentation process. Based on it, removal effect of pre-oxidation combined with coagulation-sedimentation process on Chironomus kiiensis larvae was evaluated. The results showed that chlorine dioxide pre-oxidation possessed better removal performance than prechlorinion, and Chironomus kiiensis larvae in the raw water could be completely removed by chlorine dioxide pre-oxidation in combination with the coagulation-sedimentation process at chlorine dioxide dosage of 0.8mg/L. The pH in the range of 6-8 did not affect the inactivation efficiency of chlorine dioxide, whereas pH 10 resulted in around 10% decrease in removal rate. Meanwhile, the removal rate of Chironomus kiiensis larvae improved with the temperature increasing within the range investigated of 15-30°C. The removal rate was reduced by 6.7% when temperature reduced from 30°C to 15°C.

Abstract: Comparing with the phytoplankton, there are few researches on zooplanktons. Now, many waterworks don’t monitor the zooplanktons in source water. There isn’t effective detection method for several common macro zooplanktons such as chironomid larvae, cyclops and so on, and little has been done in the field of the macro zooplanktons automatic identification and monitor. This paper puts for forward a macrozooplankton edge detection method based on wavelet packet decomposition and reconstruction. We erase the high frequency parts by applying wavelet packet decomposition in the original images and then detect the edge of reconstruction images using the common edge detectors such as Prewitt, Sobel, Roberts, Laplacian of Gaussion, Canny and so on. The experimental results show that the edge detection methods in the reconstruction image work better than in the original image.