A combined zero valent iron (ZVI) and anaerobic-aerobic process was adopted for the treatment of 2,4-dinitrochlorobenzene (DNCB)-containing wastewater. The transformation pathway, reduction of acute toxicity and enhancement of biodegradability were investigated. After pretreatment by ZVI, DNCB in wastewater could be completely converted into 2,4-diaminochlorobenzene (DACB). The ratio of BOD5/CO...

Wastewater from chemical plants has remarkable antibiotic effects on the microorganisms in traditional biological treatment processes. An enhanced Fenton system catalyzed by natural pyrite was developed to degrade this kind of wastewater. Approximately 30% chemical oxygen demand (COD) was removed within 120 min when 50 mmol/L H₂O₂ and 10 g/L natural pyrite were used at initial pH from 1.8 to 7....

The chemical contamination of water from a wide range of toxic derivatives, in particular heavy metals, aromatic molecules and dyes, is a serious environmental problem owing to their potential human toxicity. Therefore, there is a need to develop technologies that can remove toxic pollutants found in wastewaters. Among all the treatments proposed, adsorption is one of the more popular methods f...

It has generally been accepted that the formation of granules in anaerobic wastewater treatment systems requires a hydraulic upflow pattern. To evaluate this hypothesis, we operated an anaerobic migrating blanket reactor (AMBR) without a hydraulic upflow pattern, using a synthetic wastewater containing acetate, propionate, butyrate and sucrose. We provided conditions amenable to the formation o...

The photo-Fenton reaction is a promising method to treat organic contaminants in water. In this paper, a Fenton reagent enhanced by microwave electrodeless ultraviolet (MWEUV/Fenton) method was proposed for advanced treatment of nonbiodegradable organic substance in pesticide-containing biotreated wastewater. MWEUV lamp was found to be more effective for chemical oxygen demand (COD) removal tha...

In this study, three different two-stage hybrid ecological wastewater treatment systems (HEWTS) with combinations of horizontal flow (HF) constructed wetlands (CWs), vertical flow (VF) CWs and stabilization ponds (SP) were evaluated for the removal of Organic-N, NH4 + , NO3 − , Total N, Total P, Total Coliforms (TCol) and Escherichia Coli, BOD, COD and TSS. The overall goal of the study was nov...

The treatment of the industrial wastewater can be particularly difficult in the presence of toxic compounds. Excessive concentration of Chromium in soluble form is toxic to a wide variety of living organisms. Biological removal of heavy metals using natural and genetically engineered microorganisms has aroused great interest because of its lower impact on the environment. Ralston metallidurans,...