Comprehensive treatment of latex wastewater and resource utilization of concentrated liquid

Latex wastewater is a kind of refractory organic wastewater containing high concentrations of organics and ammonia nitrogen.In this work,the combined process of forward osmosis(FO)and reverse osmosis(RO)was designed to treat the latex wastewater in the whole process,achieving the water recovery rate of 99%and basically no waste discharge after the catalytic oxidation process.The turbidity of the latex wastewater was decreased to below 1 NTU by microfiltration pretreatment,and then using MgCl_2 worked as the draw solution for FO process to treat the latex wastewater.Different operation conditions including adding acid or scale inhibitor as the pretreatment methods were conducted to improve the treatment performance of the combined process.After the treatment of the whole process,the concentration of COD was less than 20 mg·L^(-1),the concentration of NH_3-N was less than 10 mg·L^(-1),and the concentration of TP was less than 0.5 mg·L^(-1)for the treated latex wastewater.The water quality met standards of industrial water reuse after the complete analysis of the treated latex wastewater,meanwhile,useful substances of L-Quebrachitol(L-Q)were successfully extracted from the concentrated solution.Therefore,the combined process of FO and RO could realize the efficient treatment and reuse of latex wastewater,which provided with some important guidance on the industrial application.

Preparation of sodium alginate gel microspheres catalysts and its high catalytic performance for treatment of ciprofloxacin wastewater

The discharge of the antibiotic wastewater has increased dramatically in our country with the development of medical science and wide application of antibiotic,resulting in serious harm to human body and ecological environment.In this work,ciprofloxacin(CIP)was selected as one of typical antibiotics and heterogeneous Fenton-like catalysts were prepared for the treatment of ciprofloxacin wastewater.The sodium alginate(SA)gel microspheres catalysts were prepared by polymerization method using double metal ions of Fe^(3+)and Mn^(2+)as cross-linking agents.Preparation conditions such as metal ions concentration,mass fraction of SA,polymerization temperature and dual-metal ions as crosslinking agent were optimized.Moreover,the effects of operating conditions such as initial concentration of CIP,pH value and catalyst dosage on CIP removal were studied.The kinetic equation showed that the effect of the initial concentration of CIP on the degradation rate was in line with second-order kinetics,and the effects of catalyst dosage and pH value on the degradation rate of CIP were in line with first-order kinetics.The SA gel microspheres catalysts prepared by dual-metal ions exhibited a high CIP removal and showed a good reusability after six recycles.The SA gel microspheres catalysts with an easy recovery performance provided an economical and efficient method for the removal of antibiotics in the future.