What is Zero Liquid Discharge (ZLD) Technology of Wastewater Treatment and its working?
Zero liquid discharge(ZLD) technology is used to treat waste water, in this process every drop of water is treated and purified with ready to use. During this process only containment from the polluted water is removed as solid waste. ZLD is a very advance and high level of wastewater treatment method that includes ultra filtration, reverse osmosis, evaporation/crystallization, and fractional electrode ionization.
ZLD is the most demanding technology to maximize the fresh or we can say reusable water and minimize the waste.
Benefits of Zero Liquid Discharge (ZLD) At a Glance for an industrial process or facility
1- With the help of ZLD, we can lower the waste volumes & decrease the cost associated with waste management.
2- Approved and followed all the industrial as well as government policies and regulation of wastewater treatment for reusability or discharging it into nature.
3- Off-site wastewater disposal is reduced to its lower level, and also greenhouse gas impact and community road incident risks getting lower with ZLD.
4- Improved performance and regulatory risk for environmental profile for future permitting with environmental agencies.
5- Some resources like ammonium sulfate fertilizer or sodium chloride salt for ice melting can be recover during the Industrial effluent treatment.
Why Zero Liquid Discharge is so much important?
On earth when the fresh and ground water is going precious day by day just because of drying underground water and wastage of water. For that it’s important to use this precious resource with a minimum wastage. Water for industries is threatened until it’s not treated. Many industries required water on low or at a large scale, some of them just use it and discharge it as waste which can affect the availability of water & can damage the environment by their polluted water.
Wastewater discharge into the nature is monitored by the Indian Government’s Clean Water Act of 1974. India, USA and China have been leading for zero liquid discharge regulations for their industry and business where water and waste is more than the normal in the last decade.
As many of the rivers and lakes are polluted by the industrial wastewater, more strict regulation and rule are came into the role with Zero Liquid Discharge plants for the industry who discharge effluent before making it into the nature.
Another very much important use of ZLD is to recovering the useful resources form the wastewater. Some organizations used the solid waste of ZLD, to make them reuse as per their need. For example, gypsum can be found from mine water and flue gas desalinization (FGD) wastewater after treatment, which can then be sold to use in drywall manufacturing.
An organization can set a target for zero liquid discharge not only for the regulations and government restriction but also can demonstrate its corporate responsibility and its goodwill towards the Mother Nature. By installing and operating an in-house ZLD plants (Sewage Treatment Plant / Effluent Treatment Plants) can reduce the cost of disposal wastewater and make water reusable. By this the impact on local ecosystem and climate can also be lower as offsite disposal truck is not used which can lead to produce fewer greenhouse gases.