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Zhang H.,Wuhan University | Zhang H.,Hubei Engineering University | Ye C.,Wuhan University | Yang H.,Wuhan University | And 4 more authors.
Chinese Journal of Environmental Engineering | Year: 2013

The effects of composite inorganic polymer flocculent (IPF), organic polymer flocculent (OPF) quantity and settling time on the removal of turbidity and total iron from oil field wastewater by means of coagulation were investigated. Optimized parameters on the coagulation sedimentation process by Box-Behnken centre-united experiment design and response surface methodology (RSM) to establish a predictive polynomial quadratic model were found to be IPF dosage of 152.15 mg/L and 143.84 mg/L, OPF of 4.14 mg/L and 4.32 mg/L, settling time of 11.77 min and 11.22 min. The experimental results of the removal rates of turbidity and total iron under the optimized condition presented better agreement with the predicted values and the deviation error was only 3%~5%. In order to compare the multivariate quadratic regression equations of turbidity and total iron, mean interpolation method was used and the two sets of optimized conditions proved to be suitable.

Zhang H.,Wuhan University | Zhang H.,China University of Technology | Ye C.,Wuhan University | Yang F.,Wuhan University | And 3 more authors.
Advanced Materials Research | Year: 2013

The objective of this study was aimed to investigate the COD removal from biologically treated coking wastewater with a multiple barrier process of coagulation-flocculation (CF)/Fenton oxidation (FO)/ powdered activated carbon (PAC) adsorption. Optimized parameters validated by a series of processes were found to be FeCl3 concentration of 320.0 mg/L, anionic polyacrylamide (APAM) of 0.8 mg/L, the mass ratio mH2O2/mFe2+ of 4.7 and 500.0 mg/L of PAC, respectively. The total COD removal of 88.1% was obtained. Furthermore, through GC/MS analyzing of treated coking wastewater by stages, which was consistent with the COD removal. The results showed that the effluent treated by the integrated processes could meet the national second-grade standard of sewage comprehensive discharge in China and the requirements of reverse osmosis (RO) feed water. This implied the multiple barrier method had promising in practical applications. © (2013) Trans Tech Publications, Switzerland.

Ye C.,Wuhan University | Zhou W.,Wuhan University | Zhang X.,Wuhan University | Zhang H.,China University of Technology | And 2 more authors.
Chongqing Daxue Xuebao/Journal of Chongqing University | Year: 2013

To moniter the operation condition of circulating water system and realize real-time prediction of the pH variation of circulating cooling water, a mathematic model of pH variation tendency is set up and the mass transfer coefficient of gaseous CO2 is calculated. Then the validity of the model is verified by quasi-dynamic simulation experiment. Results illustrate that circulating water can achieve the gas-liquid equilibrium state after it fully contacts with gaseous CO2 in atmosphere, and the maximum error limit between the theoretical and the measured pH value is only 0.04. The pH variation tendency of quasi-dynamic system is in line with the predicting mathematic model and the A·KG is a constant when temperature (T) and spray flow (Q) are fixed. 105·A·KG=0.0236Q-0.02 gives the relationship between A·KG and Q, when T is 40°C.

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