Chemical companies can evaporate and fully recycle wastewater – sustainably
19 Sep 2018
Evaporating wastewater can be expensive and energy-intensive, but it doesn’t have to be. Some companies choose to evaporate wastewater because it is the only feasible option – but solving the wastewater issue is only one aspect. Manufacturers can actually recoup their investment within 3 to 5 years if they re-use the condensate as process water.
“Considering your options is the first step,” explains Bernard De Jonghe, GEA expert in separation techniques for the chemical industry.
If a company has to treat wastewater, they must first systematically evaluate the feasibility of all available approaches. Each has its pros and cons, but also comes with a price tag in terms of investment. Evaporation technology is usually the most expensive option – but one that can easily be recouped given impressive wastewater recycling rates,” states De Jonghe.
Is water evaporation the right route for my company?
Evaporation is a separation technique that demands a substantial investment while at the same time seemingly wastes a lot of energy. The investment is considerable, but the equipment is very robust, and is built to last a generation or more. The energy consumption of evaporation can be substantially reduced with thermal or mechanical vapor recompression (MVR).
A major consideration is the composition of the wastewater – which is often variable – meaning no two batches are alike. It must be thoroughly tested to ensure the right physical parameters are taken into account and the corresponding solution can be properly dimensioned. GEA has its own test center, equipped with state-of-the-art laboratory equipment and numerous pilot plants. The tests usually begin in the laboratory and later verified via pilot plants. If necessary, a pilot plant can also be set up at the customer site so that a long-term test can be run over several weeks. Only then can GEA provide customers with realistic and reliable information about the solution, including energy consumption and purchase price.
Most companies make a financial analysis and evaluate the total costs of ownership, posing these questions:
- How much in operational costs could be saved?
- How much money could be saved if much less or no waste had to be disposed of?
- What are the tax benefits?
These savings are then weighed against the investment and energy costs.
Reusing process water and recouping ROI
The evaporation process separates water vapor from the waste stream and condenses it. Many companies are eager to recycle the condensed water in their plant as process water. However, to do this, the water has to meet specific quality requirements, which necessitates techniques such as membrane treatment, stripping and distillation. GEA has extensive experience with separation techniques in the food, pharma and chemical industries – which have to meet rigorous standards – and is well placed to advise companies in diverse sectors. Belgian medium-density fiberboard (MDF) manufacturers, Spanolux and Unilin, are both completely recycling their condensed wastewater using GEA water evaporation technology.
Future-proofing business in the face of increasing water scarcity
Water has become a precious resource – all over the world – and how we deal with it is a growing concern for society. Many companies drill wells, pumping large quantities of groundwater to cover the demand of process water. However, governments are increasingly prioritizing the use of groundwater for drinking water and levying high taxes or outright denying companies access to the water table. This is not only a concern for chemical manufacturers, but is also affecting other sectors such as the waste processing, metallurgical and textile industries.
GEA: your partner for wastewater evaporation equipment
To ensure a long lifecycle, GEA evaporation plants are constructed using the highest quality materials and according to wastewater specifications: from carbon, stainless- and duplex steel and high nickel alloys, to nickel and titanium. “GEA is second to none when it comes to product experience,” explains De Jonghe. “Our technical center in Karlsruhe, Germany, specializes in evaporation technologies and in the last 60 years, thousands of products have been tested and our technologies constantly developed. Based on this knowledge and expertise we can ensure that we’re offering customers the best technology available on the market. We also bring substantial project management support to bear for our customers and are able to draw on global resources in the areas of process technology, automation, equipment manufacturing and structural steelwork,” he concludes.
