Drivers and economic aspects for the implementation of advanced wastewater treatment and water reuse in a PVC plant

Abstract

This paper shows the economic feasibility of water reuse within a polyvinyl chloride (PVC) plant. A two-step treatment of the current primary effluent consisting of an aerobic membrane bioreactor followed by a double pass reverse osmosis process, validated at pilot scale, was used to estimate the costs of the industrial water treatment plant. The economic feasibility of the treatment and reuse concept remained unclear because the required investment of 2.5 M€ was high and the discounted payback time of 5 years was long. The proposed solution is profitable for sites where fresh demineralized water production costs are currently higher than 1.5 €/m3 and the required flow of the recycled water exceeds 50 m3/h. The water reuse concept allows decoupling the production from fresh water use. In this case, anticipating that a drought would lead to a 3% reduction of the production, the amortization period would be lowered to one year.

Keywords

• Water reuse
• Polyvinyl alcohol
• PVC effluent
• Membrane bioreactor
• Reverse osmosis
• Economic evaluation