Papers by Author: Liang Fei Dong

Abstract: This article summarizes the research situation of wastewater treatment technology with MBR and modified technology of MBR, especially introduces the efficiency of TiO2-modified PVDF membrane. MBR technology has been widely applied for wastewater treatment and reuse, while its development was always restricted by membrane fouling, but modification can effectively enhance hydrophilic and fouling-resistant ability of the membrane. This paper compares several material modification methods for MBR, and analyses the research situations of PVDF modification with several inorganic nano-particle. The modified MBR with nano-TiO2 has attracted many interests of researchers, which will have a better application and development prospect.

Abstract: According to the fuzziness of water quality in water distribution system, based on the simulation data of water quality obtained by using EPANET software,and applying entropy weight theory in the fuzzy evaluation of water quality, fuzzy evaluation model of water quality based on entropy weight and EPANET is established. Water quality in water distribution system of Hengshanqiao town is evaluated by using this method.Evaluation results are relatively objective and credible, proving that the method is simple and practical, scientific and reliable.

Abstract: In this paper, we focus on the fate of nitrogen (N) and phosphorous (P) in source-separated urine. Fresh mixed urine of pH 6.7 was diluted with different factors and stored openly and closed respectively. With pH increasing concentration of total phosphate (TP), total nitrogen (TN), ammonia nitrogen(NH₃-N) and dissolved phosphate(PO₄^3-) were measured to understand the fate of N and P in urine. Because of volatilization and precipitation, concentration of NH₄⁺-N and PO₄^3- in the urine stored closed was higher than them of stored openly with the equal dilution. Under same storing conditions, the higher dilution factor, the higher concentration of NH₄⁺-N. When stored openly the pH of the samples increasing due to urea-hydrolysis resulted in precipitation which consumed N and P, and could be promoted by dilution with tap water containing hardness ions. Because of a few of hardness ions in the urine and tap water, the amount of precipitations containing calcium, magnesium, N and P in the urine sludge of every sample were not high enough to be detected by XRD. Although more flushing water would caused more precipitation, which is also helpful for nutrient recycling, using of large deal of tap water is not economic and environmentally friendly.

Abstract: The study focuses on the degradation humic acid (HA) by a hybrid system combining a flat-sheet submerged membrane module and a photocatalysis reactor (FSMPR). The influences of UV irradiation intensity, titanium dioxide (TiO₂) and initial humic acid concentration, pH, H₂O₂ dosage were investigated in batch kinetic tests. and the relevant dynamic analysis was carried out. The transmembrane pressure (TMP) with time under the range of constant flux operation (20-40L/m²h) does not increase obviously. It was also found that aeration backflush availably reduced TMP of the FSMPR. Therefore, the FSMPR can be potentially applied in drinking water treatment.