Keeping it clean!
Water – a precious resource
Water is precious. Due to climate change and increasing demand, natural supplies of clean freshwater are dwindling. Every year, World Water Day reminds us to protect and value this resource. This year the Day’s slogan is Valuing Water because, ultimately, everyone needs to be aware of the vital importance, ecological, social, and cultural value of water.
“The value of water is about much more than its price – water has enormous and complex value for our households, food, culture, health, education, economics and the integrity of our natural environment”, says the UN about World Water Day. If we overlook any of these values, we risk mismanaging this finite, irreplaceable resource. Adding, that “if we overlook any of these values, we risk mismanaging this finite, irreplaceable resource” and that “without a comprehensive understanding of water’s true, multidimensional value, we will be unable to safeguard this critical resource for the benefit of everyone”.
Solutions for sustainable water use
LANXESS supports the guiding principle of World Water Day and
- supplies solutions that enable businesses across a wide range of industries to efficiently treat this precious resource.
- promotes the careful use of water at its own sites via its Water Stewardship Program, for example.
"Even in industries that use a lot of water and produce heavily polluted wastewater, wastewater can be radically minimized, treated and recycled."
Manager Technical Marketing
Our textile industry example illustrates how water treatment can be improved.
50 bathtubs of water for a pair of jeans
The textile industry requires enormous amounts of water for the cultivation of textile fibers, production, pretreatment, finishing, dyeing and printing. Cotton clothing in particular exhibits a poor ecological balance in terms of water consumption. For example, an 800-gram pair of jeans consumes around 8,000 liters of water, or 50 bathtubs full. By way of comparison, the average German uses an average of 122 liters of water a day each and, for roughly two months, could get by with 8,000 liters.
Wastewater treatment made easy
Thanks to LANXESS products, such as Lewatit® ion exchange resins, we can:
- remove pollutants from wastewater,
- reduce water pollution and environmental degradation,
- reduce the use of fresh water,
- counter the shortage of water.
The Indian garment industry provides a case in point.
Tiruppur – the t-shirt city
With its 450,000 inhabitants, the southern Indian industrial city of Tiruppur lives from processing cotton for export around the world. The problem:
- The textile industry consumes large quantities of water from the Noyyal River.
- It pollutes the river and groundwater with dyeing and bleaching agents.
- The chemicals used kill river life and have a detrimental effect on agriculture.
This results in water shortages and, sometimes, a dry river. The growing population lacks clean fresh water.
Low-wastewater textile production has been feasible for some time already!
If the wastewater cannot be treated effectively, Indian courts have already ruled that the dye works will have to close. However, since the textile industry is an important employer, the national government is supporting industrial water treatment efforts in order to:
- reduce water consumption,
- recycle salts used for dyeing and
- to produce significantly less wastewater.
Using contaminated wastewater in the production process
The magic needed is low-water production (minimal liquid discharge or MLD). LANXESS supplies the key technologies that, when combined properly, make highly polluted water reusable.
The solution: very fine filtration
Each type of industrial wastewater is different. Wastewater from dyeing operations is heavily organically polluted and has a very high salt content. Cleaning it involves carrying out a variety of treatment steps in succession:
- Biological treatment lowers the amount of organic matter.
- Then the water passes through a quartz sand filter that can remove particles as small as 80 micrometers, or roughly to the thickness of a human hair.
- An ion exchange resin ensures decolorization of the water by removing specific organic pollutants.
- Then the water is chemically “softened” with a special Lewatit ion exchane resin.
- The process is concluded using reverse osmosis to remove salts.
The result: clean water, reusable lye and salts
These water purification steps result in:
- clean water in which textiles can be dyed again,
- brine and salts for use in textile manufacturing,
- sewage sludge as the only waste product remaining, which can be incinerated,
- the protection and preservation of river and ground water,
- the increased availability of fresh drinking water,
- more water on hand for agriculture.