Closing the water chain by purifying waste water After purification, waste water is normally only supposed to be discharged. Now that sustainability is playing an increasingly important role in society and we are facing a shortage of fresh water, there is a growing interest in the re-use of (waste) water and closure of the water chain.
Improve your sustainable image and lower your costs with Evides Industrial Water’s RE-USE programme.
Water re-use is becoming more and more important for industry – the re-use of sub-flows and collected waste water. Both can be re-deployed after in-depth purification at various stages in the production process. The main reasons for recycling water are to reinforce a sustainable image and achieve lower costs – for example, by reducing purchase and discharge costs. The recovery of a product is another good reason. Or re-use in order to unburden an existing waste water purification plant (AWZI) so that it does not need to be expanded. Water re-use makes it possible to increase production capacity without using or extracting even more (ground) water.
The advantages of recycling waste water are obvious: a smaller water footprint and cost savings thanks to the reduced collection of drinking water; moreover, the recycling of freshwater effluent is much cheaper than the desalination of seawater, and it also produces environmental benefits and reduces the use of fresh water. That ensures that the water chain can actually be closed.
Are you interested in Evides Industrial Water’s RE-USE programme? To arrange a meeting free of obligation, email or call us for an appointment: firstname.lastname@example.org or + 31 (0) 10 – 293 51 72.
Effluent as process water
The effluent produced by waste water purification plants is actually process water. The quality of this water can indeed vary, but in most cases it is good enough to be used as industrial or agricultural water. It can also be used as source material for an upgrade to high-quality demiwater.
Over the past few decades, Evides Industrial Water has gained a wealth of experience with the use of membrane technology (MF, UF and RO). With this knowledge, we are now able to design, build and run effective purification plants that purify effluent effectively and make it suitable for re-use. This results in reliable and good-quality process water.
The advantages of recycling waste water
The advantages of the re-use of waste water are obvious: recycling of freshwater effluent is much cheaper than desalinating seawater, it produces environmental benefits and it makes an important contribution to the reduction in the use of fresh water. In this way, the water chain can actually be closed.
Applications of waste water re-use
Dow Benelux (Terneuzen) has the largest effluent-recycling plant in the Netherlands, with a capacity of 600 m3 per hour. We purify some of the industrial waste water from Dow Benelux and turn it into cooling-tower water. For Cargill, we produce demiwater from purified waste water for the production of steam, and in Delft a project has been set up to use household waste water after purification as irrigation water for the greenhouse complexes in Westland.
Water re-use Delft Blue Water: sustainable pure water for the spatial environment
At the Harnasch polder waste water purification plant (municipality of Midden-Delfland), numerous organisations are working together on a sustainable alternative for the supply of fresh water in Delfland. Under the name Delft Blue Water, research is being conducted into the possibilities of producing pure water sustainably for the surroundings (basin water and groundwater) and the horticulture sector (irrigation water).
Demonstration hall At the Harnasch polder waste water purification plant, a demonstration hall has been built in which a maximum of 50 m3 effluent per hour can be collected. The demonstration hall has two research lines: a surface water line and an irrigation water line.
Surface and irrigation water line The aim of the surface water line is to remove as much nitrogen, phosphate and suspended particles as possible. Research is also being conducted into the removal of priority substances. The irrigation water line is aimed at the cost-effective and reliable production of irrigation water in compliance with the quality requirements specified for Class 1 Irrigation water.
Delft Blue Water includes the following activities:
Technology research in DBW demonstration hall.
Study of nitrogen and phosphate recovery.
Flanking scientific research by Delft University of Technology.
Comparative tomato cultivation test with DBW irrigation water.
Regional study into the possibilities of deploying DBW surface water.
Development business case.
Water re-use Sloewarmte B.V.: a sustainable Zeeland seaport
In the port of Vlissingen, five companies are working together to recycle residual heat. The residual heat link is making a major contribution to a sustainable Zeeland seaport thanks to savings on energy use and lower CO2 emissions. Sloewarmte BV is an initiative of Evides Industrial Water, Zeeland Seaports and Martens Cleaning aimed at re-using residual heat generated at Zeeland Refinery. Customer Martens Cleaning is using the energy to process spent oil into clean fuel oil. The nearby COVRA is using the residual heat for climate control..
Heat flow The heat is captured at 130 degrees at Zeeland Refinery, after which it is transported by pipeline to COVRA and to Martens Cleaning, which uses the energy to process the collected spent oil (sludge) into clean usable fuel oil. COVRA uses the heat flow for climate control in the processing buildings and the office. Then the water is cooled to 70 degrees.
Lower CO2 emissions With Sloewarmte BV, CO2 emissions are expected to decrease annually by 4,300 tons. In addition, the residual heat link produces energy savings of around 2.4 million Nm³/j. With this saving, Martens and COVRA can considerably reduce their fossil fuel purchases.
Pipeline Evides is responsible for the construction and management of the residual heat link between COVRA, Martens Cleaning and Zeeland Refinery. Hot water transported through a 2.5-kilometre pipeline that is partly under the ground and partly above the ground. Evides also manages the pipelines and the requisite plants, and supplies the heat flow at the right end temperature to the end customers.
Green Deal Sloewarmte is part of the Green Deal that the province of Zeeland and Zeeland Seaports entered into in 2011 with the Ministry of Economic Affairs. The project involves a total investment of 3 million euros. The Central Government is contributing 1.5 billion euros, and the province 0.2 billion euros. Other investments are being made by Sloewarmte BV, Zeeland Refinery, Martens and COVRA.