Green Synergy Engineering
Reusing industry water to combat water stress
While the world's population increases rapidly, climate change continues to have a significant impact on our environment, putting our finite global water supply under pressure. Although many manufacturers operate as if recycling water supply is a matter of choice, it will soon be clear that it is in fact a necessity.
Around the world, drought and growing populations are forcing many cities to use recycled water and it is becoming essential for future sustainability. In 2018, Cape Town, South Africa, narrowly avoided ‘Day Zero’ where residents’ taps were due to be turned off following a three-year drought.
Locally, water scarcity is also forcing some industries to rethink their water recycling and treatment process to become more efficient.
So how can industries transform wastewater so that it can be reused in their processes?
Filtration and separation can be used in many areas, from flushing toilets to agricultural irrigation, to industrial uses such as in cooling towers or boilers. Dangerous particles, contaminants, and biological materials are removed in wastewater treatment plants so that the water can be returned in a safe and usable state into the environment. It normally takes several steps which require different filtration solutions. The chemical industry, for example, has a long list of chemicals they utilize when manufacturing; some of the most common chemicals are sulfuric acid for fertilizer, nitrogen for quickly freezing food, ethylene for synthetic rubber, and chlorine to eliminate pathogens. The technology to filter all these chemicals, additives, and contaminants exist - automatic self-cleaning filters would allow for no interruption due to the automatic backwash cycle; high-grade stainless materials and fiberglass-reinforced plastic are ideal for corrosive liquids or environments… For many industries it is only a matter of cost.
Long term savings
While industries have to spend on the initial setup of a wastewater treatment center, the long-term benefits can outweigh its initial cost.
For example, Dow Benelux, one of the largest chemical plant in Netherlands has made major advancements for the use and reuse of wastewater with the help of a local water treatment facility. The site reuses 30,000 cubic meters of municipal wastewater every day. By recycling water, 1L of water is used 3 times as opposed to only once.
Because of this, the plant’s energy use associated with water treatment has been reduced by 95%. This process has also cut the plant’s CO2 emissions by 60,000 tons each year.
Dow has stated it saves 1.5 million dollars annually by reusing the city’s wastewater instead of desalinating seawater.
Recycling water in all its forms will play a profound role in relieving the burden of water stress. By implementing new industrial filtration technologies and setting up wastewater treatment plants, industries can also save on electricity and water costs.