How upgrading aerobic treatment allowed membrane water reuse technology
AQUALITY® membrane technology
Increasing water efficiency
A major potato processing plant wanted to increase operations efficiency. To cut tap-water dependency, an extra wastewater treatment step was integrated, making it possible to reuse the bio-effluent from aerobic treatment into process water.
The new process allows for a considerable reduction of the water consumption per ton of finished potato product, a standard KPI for measuring efficiency in the potato processing industry.
Upgrade of the pre-treatment
Water reuse feasibility is largely dependent on the bio-effluent quality after aerobic treatment. In the Leuze-en-Hainaut treatment plant, aerobic treatment capacity reached it limits and needed substantial upgrade before water reuse was even an option. Waterleau designed and built the aerobic treatment extension by integrating additional parallel plate settlers and converting the two existing aerobic treatment plants into a single aerobic treatment system with additional aeration capacity and extra clarification.
State-of-the-art membrane technology
The water reuse process design is based on Waterleau's state-of-the-art AQUALITY® membrane technology combining ultrafiltration and Reverse Osmosis. AQUALITY® Ultrafiltration separates particulates, colloids and macro-molecules from the water using a porous semi-permeable membrane. Only small molecules such as water, monosaccharaides and ion molecules are able to pass through the ultrafiltration membrane.
Permeate quality is characterized by a low turbidity and SDI value, making it perfectly adapted for further treatment in a secondary reverse osmosis step. The AQUALITY® Reverse Osmosis technology makes use of cross-flow filtration. Only water can pass through the membrane by means of diffusion. The final permeate water has drinking water quality, to which free chlorine is added making the water perfectly suited for diverse applications within the production site.
A 40% reduction in water consumption per ton finished product
- At full capacity, each hour, up to 70 tons of potato finished product and 250 m³/h of wastewater are produced
- The new water reuse plant is designed to produce 110 m³/h of potable water, out of 165 m³/h of aerobic treatment effluent.
- AQUALITY® water reuse technology: 40% reduction of water usage per ton finished potato product
Biogas recovery from potato wastewater
The Leuze-en-Hainaut wastewater treatment design includes a pre-treatment, a BIOTIM® UASB anaerobic reactor and an aerobic post-treatment step.
At full capacity the BIOTIM® UASB treats up to 50 tons of COD/d with a biogas production of 850 Nm³/h, the equivalent of 6 MWt green energy or up to 2,5 ton of steam per hour.
The biogas production allows a reduction of approx. 10% of the potato processing thermal energy needs.
Other relevant cases
Find your local contact
Our expertise is always within reach. Digital communication has cut long distances short, but we advocate the traditional way of sharing insights.
Contact us today. We are looking forward to help you reach your sustainable development goals.