Aiming for a circular economy, Da Nang will reuse treated wastewater

(TN&MT) – Currently, Da Nang is researching and transferring technology to reuse treated wastewater and water circulation at factories, production, business and service establishments to approach a circular economy.

Many benefits

Within the framework of the project “Joining hands to protect water resources” funded by the United States Agency for International Development (USAID), Center for Environmental and Community Research (CECR), Vietnam Water Conservation Network Nam (VIWACON), Hanoi University of Science and Technology and University of Science and Technology – University of Da Nang are coordinating to implement a component to promote water reuse initiatives in businesses.

The units have installed a demonstration system to reuse treated wastewater with a water usage capacity of 10 m3/day at a resort in Ngu Hanh Son district to water trees and vegetation in the resort. . At the same time, install a similar system with a capacity of 15m3/day at the seafood processing factory of Thien Ma Company Limited in Tho Quang Fisheries Service Industrial Park (Son Tra district) for irrigation, washing, Helps cool and clean the factory.

After installation, testing and technical adjustment, the quality of reused water meets the set requirements and saves money, reduces wastewater treatment costs, reduces natural resource use taxes, and reduces water exploitation fees. underground and reduce water usage fees payable by businesses.

Director of Thien Ma Co., Ltd. Le Van Vuong shared that after going through the adsorption and filtration system, the treated wastewater ensures quality for reuse. With a reuse capacity of 15 m3/day of treated wastewater, it helps the company reduce the cost of connecting and treating wastewater by 130,000 VND/day (8,600 VND/m3), and reduce the water bill it must pay (15,000 VND/day). VND/m3) and there are also grounds to reduce natural resource use tax. Currently, the company is reusing treated wastewater for cleaning, floor irrigation, factory cooling… and is researching the use of cooling water for freezing and air conditioning systems.

“Reusing water brings many benefits, so we also hope to research to increase the capacity of reusing all daily treated wastewater of the plant,” Mr. Vuong said.

According to Ms. Dang Nguyen Thuc Anh, Deputy Head of Minerals and Water Resources Department (Department of Natural Resources and Environment of Da Nang City), in resorts, using local water to water plants is inappropriate and the cost is 10 times higher. Compared to exploiting groundwater, most businesses choose the solution of exploiting groundwater to irrigate plants. In recent years, the city has encouraged and mobilized businesses to invest and upgrade wastewater treatment systems to ensure that the quality of treated water can meet regulations for watering plants. There are many coastal resort investors who support this policy and implement it very well, including 7 businesses that have upgraded their wastewater treatment systems.

“In the coming time, when tourism is restored, businesses will have the conditions to invest and upgrade wastewater treatment systems at resorts to reuse for watering purposes, gradually replacing mining. underground waterfall,” said Ms. Dang Nguyen Thuc Anh.

Promote reuse of wastewater

Dr. Nguyen Dinh Huan, Dean of the Faculty of Environment, Polytechnic University – University of Da Nang said that in order to successfully implement the project “Building Da Nang – Environmental City”, during the process of reviewing and approving the assessment report, Dr. environmental impact assessment, authorities need to require businesses to have solutions to save and reuse water. This will certainly make businesses find ways to incorporate water saving and reuse into projects.

This will help businesses gain economic benefits such as: reducing monthly water bills, reducing wastewater treatment fees… The system of reusing treated wastewater when mass produced will have costs. Appropriate fees, meeting the water reuse needs of businesses, can take advantage of businesses’ existing tanks, tanks and equipment for installation. This system is feasible and environmentally meaningful when replicated, so reuse of treated wastewater at businesses should be promoted.

Da Nang has invested a lot in building an extensive wastewater collection and treatment system with a total wastewater treatment capacity of nearly 350,000 m3/day. Treated water is an extremely valuable resource and has great potential for water reuse. In the dry season, the water level of lakes, canals, etc. drops, causing environmental incidents, especially fish deaths, spreading bad odors into the environment, etc. Therefore, the city needs to pump reserves of treated wastewater. has met standards with a total capacity of nearly 350,000m3/day to the upstream of canals and lakes to create circulating water flow, ensuring the environment and regulating the climate.

To promote the reuse of treated wastewater, Ms. Nguyen Thi Kim Ha – Deputy Director of the Environmental Protection Branch (Department of Natural Resources and Environment of Da Nang City) said that currently the Department of Natural Resources and Environment is coordinating with organizations , a domestic and foreign unit specializing in research and transfer of wastewater reuse technology from domestic and industrial wastewater treatment stations as well as solutions for reusing wastewater after treatment and circulating water at wastewater treatment plants. factories, production, business and service establishments.

Source: Lan Anh – Tài Nguyên Môi Trường newspapers