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Planet ZLD – Why Zero Liquid Discharge is Essential to Our Planet

Planet Zero Liquid DischargeIn recent years, Zero Liquid Discharge (ZLD) has evolved from a costly process to a viable solution for environmental protection. What was once thought of as a “nice to have” method, ZLD filtration systems are becoming an essential solution for manufacturing facilities to adhere to new wastewater discharge regulations, lack of (or limited) municipal water treatment infrastructure, and fresh water supply shortages. As industries adapt to increasingly strict regulations and improve the quality of our global water supply, we can truly become Planet ZLD and thereby significantly address the global water crisis.

The Current State of Water

The World Economic Forum announced in 2015 that the water crisis is the #1 global risk based on impact to society. Approximately 1 in 9 people on the planet lack access to safe water, and that number is growing with increasing pollution and its impact on the water supply.

Even the United States is beginning to feel the impact of the global water crisis. There is news of regional droughts, global warming concerns, and territorial fights over watersheds.  As water scarcity becomes a growing global issue, safety concerns of existing water supplies become more immediate as well. Less than a year ago, residents in Toledo, Ohio were placed under a state of emergency due to the presence of unsafe pollutants in the water supply. Outside of Toledo, a study done by the Environmental Working Group found that excess levels of Chromium-6 existed in 31 of the 35 tested cities, with some cities exceeding the recommended limit by more than 100%.

In the United States and globally, runoff from industrial manufacturing plants is a primary culprit in water contamination. The impact of water contamination can go undetected for many years.  With water scarcity an increasing concern, it is vital that drinking water remains clean and safe for everyday consumption.

A Move to Accountability

In order to address the increases in water pollution, governments are holding corporations accountable for their water consumption and wastewater discharge practices.  In the United States, a major law governing water pollutions is the Clean Water Act passed in 1972. The regulations require any entity that is discharging pollutants into the water of the United States to obtain a National Pollution Discharge Elimination System (NPDES) permit. The permit does place stringent requirements on pollutant levels, but fails to effectively eliminate the transmission of pollutants into drinking water.

Older regulations are being revised as new standards for water quality are being established by global organizations who are putting updated guidelines in place.  Federal and local governments across the globe are adopting these new guidelines and moving quickly to enact stricter discharge regulations.  Production plants will be expected to comply or face heavy penalties.

Zero Liquid Discharge

Presently in the US, production plants are required to renew their NPDES permit every five years. The time it takes to renew a permit can range anywhere from a few months to over a year, leaving the plant susceptible to incur compliance costs or even close down due to failure in meeting regulations.

The key to removing pollutants from being discharged, and to ensure complete compliance with government regulations, is to implement a Zero Liquid Discharge filtration system. ZLD systems utilize the most advanced wastewater treatment technology to clean and reuse essentially all wastewater produced by a facility. Put simply, a ZLD system means that no liquid waste leaves a facility, and is essential to ensure our water remains safe for generations to come.

How Does Zero Liquid Discharge Work?

A ZLD system contains several processes that together separate unwanted substances from the waste water to produce high quality water for reuse.  ZLD processes virtually eliminate all waste water discharge. 

Many industrial processes introduce a mixture of organic and inorganic substances to processing water that essentially turn it into waste. Many of these substances can be broken down by biological and chemical processes and turned into insoluble, suspended particles. A membrane microfiltration system incorporating POREX® TMF™ filters can efficiently remove the suspended particles to produce high quality water.  This water can then be fed into a reverse osmosis (RO) membrane system, which produces even higher quality water that can be reused. 

The net result is that the whole ZLD system produces only high quality fresh water and solid waste. The solid waste is further processed as “cake material” and easily removed from the site and not discharged into the environment.  High quality water produced from the TMF system, and subsequently fed into the RO system, is the key ingredient in engineering an efficient ZLD system operation.

Becoming Planet Zero Liquid Discharge

By implementing a Zero Liquid Discharge strategy, industrial production plants can reduce costs, reduce environmental impact, and align with evolving global guidelines and regulations. Protecting the water on our planet is a concern for everyone, and provided nations continue to hold corporations accountable for their impact on the water supply, we can move to become a ZLD planet with safe, clean drinking water globally.

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