Study On Treatment Of Butyl Acrylate Wastewater By A Combined Process Of Micro-aerobic,Anaerobic, Aerobic Bed

The influence of acrylate and p-toluenesulfonate on methane-producing acitivitywas investigated. A novel combined process of microaerobic-anaerobic-aerobic wasdeveloped for butyl-acrylate wastewater treatment. The influences of organicconcentration, hydraulic retention time (HRT) and salinity on pollutant removalefficiency of the conbined process was studied. The conclusions are as follows.Both acylate p-toluenesulfonate could inhibit methane-producing acitivity andacrylate was more toxic. The semi-effective concentrations(EC50) of acrylate forinhibition of methane-producing activity with acetic acid and propionic acid assubstrates were717mg/L and235mg/L, respectively.Microaerobic bioreactor could remove98.5%of acrylic acid (AA) frombutyl-acrylate wastewater containing acrylic acid of4000-8000mg/L at a HRT of12h.Acetic acid of200-2000mg/L and propionic acid of2000-4000mg/L were produced.The effluent acrylic acid was below126mg/L and its inbibition effect on methaneproduction was significantly decreased.Expanded granular sludge bed (EGSB) reactor was used for treatment of themicroaerobic effluent. HRT of the reactorwas12h and loading rate was18kgCOD/（m3·d）.The chemical oxygen demand (COD) removal efficiency of the reactormaintained at89%-91%with an effluent COD of695-850mg/LThe combined process was used for treatment of butyl-acrylate wastewater.Influent COD was maintained at10000mg/L and HRT of the combined process was37.5h with a overall loading rate of6.4kg/(m3·d). Organics in the wastewater wereremoved steadily.COD removal efficiency was above98%and the effluent COD wasbelow310mg/L.When the influent wastewater had a COD of20000mg/L and total dissolved solid(TDS) of24g/L, the combined process was operated with a effluent recyling of100%.The loading rate of the whole process, microarobic bioreactor, EGSB reactor was6.4kgCOD/(m3·d),14.2kgAA/(m3·d) and18.6kgCOD/(m3·d), respectively. COD removalefficiency was above97.8%and the effluent COD was below450mg/L.