Applied Mechanics and Materials Vols. 295-298

Abstract: This paper makes the amoxicillin production wastewater as the research target and uses the microwave-activated carbon to treat this kind of wastewater. The results show that 6g of the 60 purpose granular activated carbon mixed with 50ml of the wastewater that diluted 10 times and the pH value is 9 under the condition that irradiated power up to 480W and the irradiation time for 7min, the COD removal rates is up to 96.38% and the effluent COD value is 48.28mg/L.

Abstract: Heavy metal pollution is one of the main obstacles of municipal sewage treatment plant sludge for agricultural use. This paper gives an overview of four kinds of commonly used techniques for heavy metals removal in sewage sludge: chemical extraction, bioleaching, electrokinetic technology and solidification - stabilization, also analyzed the future direction of development.

Abstract: Urease was successfully tethered onto coconut shell activated carbon (AC) granules. Degradation of urea was carried out in packed bed over the tethered urease. For 75% of retained activity, the tethered urease shows a broader temperature range of 42~80°C, compared to 45~75°C for the free enzyme. Similarly, the tethered urease has an increased resistance against the changes of pH. For a relative activity of 80%, the free urease had a pH range of 6.2-7.4, while it was 6.5–8.0 for the tethered urease. The Km values of the free and tethered ureases were 22.60 mg/mL and 7.43 mg/mL, respectively. And the Vm values were actually very close (~23.5 mg/min ) for both the tethered and free ureases. The catalytic performance of the tethered urease was tested in a packed bed reactor. The relative activity was maintained over 80% after 50 h of running in degradation of urea.

Abstract: The vast majority of PRB currently in use utilize zero valent iron (ZVI) as the reactive medium. In this paper, three laboratory columns were set up and operated under conditions simulating those anticipated in the groundwater to investigate the feasibility and efficiency of the enhanced Fe⁰ PRB for the remediation of the PCBs contaminated groundwater. Operating under 10°C and an effective porosity of 61% to 67% and infiltration velocity of groundwater of 0.7 to 0.8m•d-1, the average iron concentration of effluent was 0.241mg•L-1, 0.129mg•L-1 and 0.201mg•L-1, respectively, and the average dechlorination efficiency reached 49.6%, 72.6% and 58.6%, respectively, the Fe0/Zn0 based columns can accomplish 94% of PCBs removal and pH value raised from 6.87 to 10.2. Comprehensive consideration suggested that Fe0/Zn0 based PRB technology is feasible for the remediation of PCBs contaminated groundwater.

Abstract: In this paper, a new kind of nano-silica embedded cryogel was prepared by solution crosslinking isobutylene-isoprene rubber with silica in benzene at various temperatures. The characteristics of cryogels were manifested by SEM. Sorption tests showed that the cryogels were efficient at removing kinds of oil, aromatic compound and alkane. The results suggested that the maximum sorption capacity was 15.44 g.g^-1 for crude oil, 15.62 g.g^-1 for diesel and 13.16 g.g^-1 for lubricating oil, respectively. Moreover, the cryogels were reusable once they were centrifuged, leading to continuous sorption capacity for these oils. Therefore, the cryogel might be a promising removal material which can be used in large-scale oil or toxic organic liquids spills.

Abstract: The main formation condition and harmfulness of the acidic mining waste water's were analyzed in this paper. The treatment technology of the acid mine drainage's was briefly introduced. The research development of acid mine drainage was summarized in recent years. It was the fact that developing the efficient, cheap, safe and easy treatment technology of acid mine should be necessary and inevitably and some success management experiences of acidic waste water were applied in acidic mining wastewater.

Abstract: In this study, the alternating 3-stage biological aerated filter system with the brush as the filler was proposed for campus sewage treatment and the biofilm formation process was researched. Adopting the four-stage inoculated biofilm formation method, the treatment effects of the 3 filter columns respectively lasted 23d, 20d, 23d to reach stable. After the attached biofilm grew steadily, the effluent COD concentration was between 45 mg/L and 95 mg/L, and the removal efficiency was 77%~85%. The effluent NH₄⁺-N concentration of 1st and 3rd filter columns was 11~25 mg/L, and the removal efficiency was 47%~67%; while the effluent NH₄⁺-N concentration of 2nd filter column was 8 ~19 mg/L, the removal efficiency was 64%~ 78%.

Abstract: A pharmaceutical factory in Wuhan produces many pharmaceutical wastewaters every day. The wastewater raw water quality indexes are: the concentration of COD,BOD₅, NH₃-N,TP is 300,000mg/L, 200,000mg/L, 450mg/L,900 mg/L ; By the SBBR treatment, the effluent water quality indexes are:750mg/L,350mg/L,1.20mg/L,5mg/L,and the effluent water can accord with Wastewater quality standards for discharge to municipal sewers (CJ 343-2010) and be discharged after treatment in the sewage treatment plant by municipal sewers.

Abstract: Aim at experimenting the micro-polluted characteristic of Huaihe River water, a pilot-scale test by the combination process of ozone/ultraviolet (UV) /biological activated carbon (BAC) filter for advanced treatment of drinking water was applied. The removal efficiency of general pollution indexes by combined process with different ozone dosages (1.0~3.0 mg/L) was investigated. Along with the increase of ozone dosage, the removal efficiency of COD_Mn and UV₂₅₄ generally increased in ozone/UV oxidation process; The removal effect of NO₂^--N by ozone/UV oxidation was obvious; The removal of turbidity and NH₃-N was mainly in BAC filter phase; When the ozone dosage was 2.0~2.5 mg/L, the general pollution indexes had gotten satisfying results, thus it was not necessary to increase the ozone dosage.

Abstract: High ferric-based silicon coagulant is a kind of new self-made coagulant. The high ferric content was introduced in the preparation process of the coagulant, and the effect was good in dealing with simulated industrial wastewater with lead. The beaker test indicated that the lead removal rate reached the highest 96.48% when the rapid stirring speed was 300r/min and stirring time was 1min, low stirring speed was 80r/min and stirring time was 15min, the dosage of the coagulant was 3.5ml/L. And the fractal dimension of flocs was 1.67674 under that optimum conditions. The low stirring stage was divided into three different stages in the orthogonal experiment of energy consumption, and the result showed that the optimum combination of flocculation was: velocity gradient G1=67.7s-1, stirring time T1=4min; G2=57.8 s-1, T2=5min; G3=23.9s-1, T3=6min. The removal rate of lead ion improved and the energy consumption decreased when the flocculation was divided into different stages. The relations between fractal dimension and energy consumption distribution can be obtained by calculated the fractal dimension of different stages. The stirring speed can be controlled and the flocs can be prevented from being broken by observing the flocs.