The ZLD process
Application of Zero Liquid Discharge in India
Water scarcity and government regulations have led to Zero Liquid Discharge (ZLD) becoming a necessity for all types of industries in India. Zero Liquid Discharge is an innovative technological solution for treating wastewater, where nearly 100% of wastewater is recycled and utilised, thus avoiding any discharge of liquid into the environment.
In this blog, we will explore the process of ZLD, the treatment process for this technology, and why this technology is increasingly essential for the dairy and pharmaceutical industries of India.
What Is Zero Liquid Discharge (ZLD)?
A Zero Liquid Discharge is a wastewater treatment technique that seeks to fully eliminate the liquid discharge. Rather than disposing of the treated water in rivers and drains, a zero liquid discharge process is capable of extracting useful water and taking the remaining wastes to be converted to solid matter.
However, with the rise in the level of enforcement from the pollution control boards in India, ZLD has become an imperative process in water-intensive industries.
How ZLD Works in Wastewater Treatment?
The ZLD process also uses several processes of treatment within its system. These are intended for the recovery of water.
1. Primary Treatment
This is the first step where large solids, oils, and other suspended materials are removed. In this stage, various machinery ranging from screens, grit chambers, and Dual Clarifiers DAF is commonly used to remove oils, greases, and other suspended materials.
2. Secondary (Biological)
The organic matter present in the wastewater decomposes due to biological activity during this phase. Aeration tanks, MBBR systems, or activated sludge systems are used to reduce the BOD and COD levels.
3. Tertiary Treatment
Technologies such as sand filters, carbon filters, or membrane processes (UF & RO) are employed for the treatment of the water in the subsequent stage to ensure that the treated water meets the standards required for its reuse in industries.
4. Evaporation and Cryst
The water rejected from the RO is treated with the application of evaporators and crystallizers. Water is obtained through condensation, while salts are changed to solids. The latter can be disposed of or reused, depending on the situation.
Importance of ZLD in Indian Industries
There are several reasons.
The Zero Liquid Discharge process is widely used in several industries in India. This is mainly because the ZLD process has the capacity to treat wastewater effectively, and several industries in India require the same process for effective water treatment. Among some of the sectors in India using the ZLD process are textile industries, chemical industries, and pharmaceutical companies. An example is the textile industries, which require the ZLD process to treat water used in its production.
Textile Industry
The textile industry in India adopts the ZLD process for the treatment of water used in the textile industry. This is because the textile industry generates large amounts of wastewater that must be properly treated for reuse. The ZLD process is critical in the textile industry because it provides an opportunity for the recycling of water for use in various activities. Hence, the textile industry in India adopts the ZLD process for the recycling of water used in textile production.
Chemical Industry
The ZLD process is also significant in the chemical industry found in India. Notably, the chemical industry employs the use of different chemicals that demand the treatment of water utilising the ZLD process. In India, the chemical industry employs the ZLD process to treat the water used in the process of producing chemicals. Consequently, the chemical industry in India is reliant on the ZLD process to recycle the water used in the process of manufacturing chemicals.
Pharmaceutical Industry
The ZLD process is also significant in the pharmaceutical sector in India. This is because the pharmaceutical sector needs the treatment of water by the ZLD process to manufacture pharmaceuticals. The pharmaceutical sector in India recycles the water used in the manufacture of medicines through the ZLD process.
Conclusion
In conclusion, the Zero Liquid Discharge process is an important one in the various industries found in India. This is because the ZLD process can treat water effectively. Various industries in India rely on this process for their water treatment.
For industries such as processed foods, dairy, and chemical processing, wastewater generation is high. ZLD technology assumes importance in reducing high organics efficiently in accordance with environmental regulations for dairy equipment manufacturing industries.
At this juncture, it is important for professional solution providers such as Ishaan Paryavaran Pvt. Ltd. to play a critical role in rendering industry-specific solutions for ZLD treatment, based on the nature of the generated effluent.
Advantages of Zero Liquid Discharge
Zero liquid
Near 100% water recovery
There shall be no discharge of wastewater into the environment.
Reduction in dependence on water resources
Implementation of CPCB and SPCB norms
Cost savings with recycled water
Why ZLD Is the Future of Wastewater Treatment in India
Due to increased levels of water stress and stringent laws concerning environmental pollution, ZLD is no longer an option but a necessity. The implementation of ZLD by industries not only ensures that the environment is green and healthy but also ensures that sustainability goals are met.
Nevertheless, modern techniques such as Dual Clarifier DAF systems, membranes, and evaporation techniques are breaking new ground in wastewater treatment, particularly in the dairy, textile, and chemical sectors.
Conclusion
Zero Liquid Discharge is an eco-friendly and sustainable process for efficient wastewater management, resulting in no adverse impact on the environment and optimal reuse of water. With stricter environmental standards emerging in India, ZLD is set to be one of the major drivers in sustainable development in industries. Collaboration with seasoned technologists in wastewater treatment helps in the efficient functioning of this technology.
