What leads us to Zero Liquid Discharge Systems?
The Zero Liquid Discharge (ZLD) treatment method aims to completely eliminate, all liquid waste from a system. The goal of ZLD is to produce clean water that is suitable for re-use, while also reducing wastewater costs.
Traditional ZLD methods include brine concentrators and crystallizers, which use thermal evaporation to transform the brine into very pure water, and solid dry product appropriate for landfill disposal, or for salt recovery. Although evaporator/crystallizer systems are the most frequently used in ZLD processes, other promising technologies with high recoveries have also gained traction, and are used in various combinations to reduce the cost, and increase the efficiency of ZLD processes, leading us to more effective Zero liquid discharge systems.
Factors leading to Zero Liquid Discharge Systems
1: ZLD is required when there is a lack of water, or when the local water bodies are governed by laws prohibiting the discharge of brine, due to the environmental effects. So many industrial sites and brine effluent producers, who up until now either discharged brine to surrounding surface water, or the sea, or to wastewater treatment facilities, are looking for innovative approaches to deal with this problem.
2: Strict rules that make ZLD vital to protect the future of the rivers and lakes, have been implemented in India, over the past ten years, as a result of the substantial industrial effluent contamination of local waters. Government fines and the cost of disposal technologies, cause these costs to rise dramatically.
3: ZLD can be used to extract valuable resources from wastewater, which can be used in industrial processes or sold. Here are a few examples:
· Using a salt mine to produce important potassium sulphate fertilizer,
· Producing 50 - 99% pure caustic soda (NaOH) concentration,
· Pure sodium sulphate (NaSO4) can be recovered from a battery production site,
· Lowering the cost of treating wastewater from coal mines, by obtaining pure sodium chloride (NaCl), which can be used to make road salt,
· Mine water and flue gas desalinization (FGD) wastewater, can both be used to recover gypsum (CaSO4.2H2O), which can then be sold and used to make drywall.
4: It can be used for recycling priceless materials from waste streams.
5: It can lower waste volumes and costs of management.
6: It can lower the price of trucks used for off-site disposal.
The following are additional benefits of using ZLD:
1: The price of waste management is reduced when the volume of wastewater is reduced.
2: Reusing water on site reduces the need for water intake, while still meeting treatment requirements.
3: It reduces the environmental concerns associated with off-site disposal.
ZLD might be a good option if your facility wants to stop releasing these pollutants into deep wells, streams, sewers to publicly owned treatment works (POTWs), and other waterways. Just keep in mind that, in reality, ZLD frequently only makes fiscal and environmental sense, when specific conditions are met. For instance, ZLD might be useful if the facility is in an area without sewers, and is prohibited by law from discharging its waste to the environment.
Finding a system for your company that is both economical and environmentally friendly can be difficult, particularly in light of the increasingly stringent effluent rules that are limiting your alternatives for discharge. That is why; you must consult experts, like Netsol Water, to manufacture your ZLD Systems.