Biological wastewater treatment for fried corn producer

Scenario

In the facilities of Tostaderos Sol de Alba S.A. where the production of fried corn is carried out, there is a pre-treatment of the wastewater that is insufficient to meet the discharge requirements. An FBR type biological treatment is designed and installed, fed by the effluent of this pre-treatment. 

SIGMA designs and installs a process FBR ('flotation bio-reactor') consisting of an aeration reactor where the biological treatment is carried out (this biological process consists of the transformation of the organic matter contained in the wastewater to be treated into microbial flocs by adsorption and agglomeration) and a separation of the biomass by flocculation and secondary clarification by DAF flotation (in this process biomass flocs are formed and separated by flotation with micro-bubbles of air in a DAF FPAC-PWL-35 equipment. With this special equipment, sludge with a dry solids content 3 or 4 times higher than any conventional system is obtained). 

The SIGMA DAF FPAC-PWL flotation unit is a cross-flow separator designed to treat wastewater with a high solids load. 

In the SIGMA DAF flotation equipment, a perfectly clarified water is obtained that can be discharged in compliance with the discharge requirements and a sludge that is partly recirculated to the biological reactor to maintain a stable biomass concentration and partly extracted as a purge. The addition of polyelectrolyte to the clarification system allows the generation of easily separable biomass flocs and provides a high biomass concentration inside the reactor and therefore a higher yield than in other suspended biomass biological systems. 

The SIGMA DAF FPAC-PWL flotation system is a modular system that is easy to expand and highly adaptable to different biomass concentrations. 

Pretreatment effluent characteristics

FBR biological treatment performance 

Process diagram