Advanced treatment of effluents from an agrochemical formulation plant

Industrial waste water treatment has developed tremendously over the last two decades. Especially biological treatment methods, originally almost solely used for readily biodegradable effluents of the food and beverage industry, have gained territory in the more difficult areas of oil refining, petrochemical and chemical industry. However with certain exceptions biological methods are not very reliable with very refractory effluents, certainly not in cases of high concentrations of toxic or inhibitory compounds. In the underlying presentation an example is given of the application of integrated biological and chemical oxidation of effluents from the use and production of insecticides and herbicides. The chemical oxidation utilises a catalysed parallel activity of ozone and hydrogen peroxide. The method is particularly suited for concentrated effluents and consumes little chemicals as compared to other chemical oxidation processes. In order to improve its efficiency the unit can be extended with a membrane filtration configuration. The commercially proven application on agrochemicals rinse waters is discussed as well as the screening test on effluent from a facility for the formulation of crop protection products. For the latter a comparison with earlier Biorotor tests is given. This paper focuses on the efficiency of the combined action of chemical and biological oxidation.