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Understanding of mass transfer kinetics is important for biosorption of nitrogen compounds from palm oil mill effluent (POME) to gain a mechanistic insight into future biological processes for the treatment of high organic loading wastewater. In this study, the rates of global and sequential mass transfer were determined using the modified mass transfer factor equations for the experiments to remove nitrogen by aerobic granular sludge accumulation in a sequencing batch reactor (SBR). The maximum efficiencies as high as 97% for the experiment run at [kLa]g value of 1421.8 h−1 and 96% for the experiment run at [kLa]g value of 9.6 × 1037 h−1 were verified before and after the addition of Serratia marcescens SA30, respectively. The resistance of mass transfer could be dependent on external mass transfer that controls the transport of nitrogen molecule along the experimental period of 256 days. The increase in [kLa]g value leading to increased performance of the SBR was verified to contribute to the fu...

This study examined the degradation of pesticide aqueous solution containing chlorpyrifos, cypermethrin and chlorothalonil by the FeGAC/H2O2 process. Under the operating conditions (FeGAC 5 g/L, H2O2 concentration 100 mg/L and pH 3), chemical oxygen demand (COD) and total organic carbon removal were 96.2 and 79.2%, respectively, and biodegradability (BOD5/COD ratio) increased from 0 to 0.40 after 60 min reaction. Complete degradation of chlorpyrifos, cypermethrin and chlorothalonil pesticides active ingredients occurred in 1 min. Kinetic models such as pseudo-first-order, pseudo-second-order and intraparticle diffusion were evaluated. The Fourier transform infrared spectra (treated and untreated pesticide aqueous solutions) also indicated modification and/or degradation of the pesticide organic bonds. The study showed that FeGAC/H2O2 process can be used for the pretreatment of pesticide aqueous solution containing chlorpyrifos, cypermethrin and chlorothalonil before further treatment by biological...

In this study, four dye-degrading bacteria, Bacillus pumilus strain ZK1, Bacillus cereus strain ZK2, Brevibacillus panacihumi strain ZB1, and Lysinibacillus fusiformis strain ZB2 were used for the development of granule. Sterile sludge was used as seeding agent in a sequencing batch reactor under intermittent facultative anaerobic–aerobic system followed by subsequent textile wastewater treatment. Physical and morphological characteristics of the granules were determined after 112 d of development time. The average size of the mature granules reached 3.3 ± 1 mm, with integrity coefficient of 25 ± 2, settling velocity of 56 ± 5 m h−1, and sludge volume index of 35 ± 5.5 mL g−1. Mixed liquor suspended solids and mixed liquor volatile suspended solids were 12.9 ± 0.8 and 11 ± 0.6 g L−1, respectively. The developed granules showed 61% of decolorization and 46% of COD removal at HRT of 24 h. The population distribution of the bacteria consortium in mature granules developed into subsequent ratio of 1:4...

This review is intended to critically convey information on water magnetization and to discuss each application that employs magnetic field as an aid in wastewater treatment. The magnetically assisted wastewater treatments are presented and compared in terms of performances with those of conventional treatment systems. The advantages and limitations of magnetic field application are discussed in order to evaluate their environmental benefits. The main conclusion from the literature review is that magnetic field application has the potential to improve the physical performance in terms of solid-liquid separation mainly through aggregation of colloidal particles. The application is also significant in influencing the biological properties through the improvement of bacterial activity. Both of these enhancements lead towards increase in efficiency of the water and wastewater treatment performances.

Factorial design and response surface methodology were employed to investigate the effects of substrate (500–3,000 mg/L) and riboflavin (1–150 μM) concentrations on the chemical oxygen demand (COD) and color removal with biogranules in the treatment of textile effluent using sequential anaerobic–aerobic batch experiment. Both variables, except for the concentration of riboflavin under anaerobic conditions, and the interaction between both variables show significant effects on COD removal. The substrate and riboflavin concentrations also significantly affect on the decolorization of Synozol Red K-4B and Sumifix Navy Blue EXF. In addition, the effect of substrate on color removal was found to be time dependent. The highest COD removal was 85.5%, which corresponds to substrate and riboflavin concentrations of 2,634 mg/L and 23 μM, respectively. The highest color removal for Synozol Red K-4B and Sumifix Navy Blue EXF was achieved after 12 h of treatment, with more than 80% color removal at substrate a...