Why waste water? That’s the question we’re all being asked this World Water Day. Wastewater may not be something we spend much time thinking about, but it should be. Reducing wastewater and reusing it wherever possible can help preserve this vital natural resource.
There are plenty of tips on how to reduce wastewater at home. Turn off the tap while brushing your teeth. Put a block in your toilet cistern. Take a shorter shower. Those things certainly help, but World Water Day is about thinking big as well as thinking small. So how about this: one factory in Mexico decided to take more drastic action. It turned off the taps completely and its water consumption has gone from 1.6 million litres a day to zero. How’s that for an answer to the ‘why waste water?’ question?
Milking the benefits
The Nestlé dairy factory has become the company’s first ‘zero water’ manufacturing site in the world. Located in the central, water-stressed state of Jalisco, it now uses only recycled water from its dairy operations. Put simply, instead of drawing water from the ground or mains, the factory gets all the water it needs from the milk it processes. The facility takes fresh cow’s milk, normally around 88% water, and heats it at low pressure to remove some of its water content.
The resulting steam is then condensed and treated and used to clean the evaporating machines themselves Once the machines have been flushed out, the water is then collected once more, purified and recycled a second time. No outside water is used at all. Water supplies have come under severe strain in Mexico due to population growth. So, saving groundwater is vitally important for the wellbeing of local populations.
"In Mexico, and around the world, water is a vital and fragile resource,” says Nestlé’s Paul Bulcke. “Due to the relevance of water in the production of food and its role in the preservation of life, Nestlé worldwide will continue to pursue initiatives that contribute to the maintenance and access to natural resources."
Three ways to save
The world’s biggest food company uses a 3-phase approach to reduce water in its factories.
First, engineers look for ways to optimise the existing manufacturing processes. Second, they look for opportunities to reuse the water already being used. In the third phase, they come up with new ways of extracting water from raw materials and recycling it. The dairy factory in Mexico is a great example of this ‘third-phase’ innovation.The triple-pronged approach has been used in more than 80 factories worldwide, enabling reductions in water usage of 10%-30%.The Mexican factory has been such a success that work is already underway to transform Nestlé’s milk factory in the Californian city of Modesto to ‘zero water’. The CHF 7 million project should save nearly 286 million litres per year when it is completed in 2018.
A precious resource
The global research organisation World Resources Institute is helping Nestlé save water by ensuring water management is environmentally, socially, and economically beneficial.
Innovation and careful management has helped Nestlé cut water consumption by a third over the past 10 years. But the job is never done. The company is committed to staying at the forefront of efforts to increase efficiency and reduce all types of waste wherever possible.
The United Nation’s sixth Sustainable Development Goal is to halve the proportion of untreated wastewater and increase water recycling and safe reuse. Industry is essential to meeting that target. Projects like the ‘zero water’ factory show what is possible and highlight the value of constantly asking ‘why waste water?’