With an increase in water shortages all over the world, water scarcity has become one of the biggest threats to our society today. Water recycling and Wastewater treatment presents a sustainable solution to this water scarcity. Wastewater is the water used by residences and commercial/industrial establishments that has become too polluted for further use. Filtering this through the water treatment process does not only produce clean reusable water, but also has the potential to produce energy.
In its efforts of promoting clean sustainable solutions to water scarcity, on Wednesday, 2nd Oct 2019 Hisaar Foundation team visited the wastewater treatment plant facility of Yunus Textile Mills at Landhi, Karachi. Facilitated by Ms. Amber Imran, CFO, ATC Holdings, Hisaar Foundation Think Tank members Mr. Zohair Ashir, Mr. Mahmood Nawaz Shah and Research Associate Ms. Daniya Khalid were briefed about the different stages of the water treatment processes at the plant.
In its primary stage, wastewater from the textile mill is pumped to the offsite treatment plant and passed through a primary sedimentation tank where solid particles are removed by gravity settling at the bottom of the tank. The wastewater then undergoes a biological process known as activated sludge process, which uses natural occurring micro-organisms to break down dissolved and suspended organic solids. The settled wastewater then enters aeration tanks where air is blown into the water to provide oxygen promoting the growth of microorganisms. These microorganisms then consume the organic pollutants in the wastewater. From the aeration tanks the mixture of wastewater and microorganisms is then passed into Membrane Bioreactor (MBR) for ultrafiltration and finally goes through the Reverse Osmosis plant before being pumped back to the plant. The treated grey water has a TDS measuring 80 and pH value of 6.5 optimized for its utility at the textile mills.
The effluent produced is treated further and is ensured of high quality enough to be eventually discharged into the sea as per the regulation of the Sindh Environment Protection Agency. The Wastewater Plant owner Mr. Ali explained that the Textile mills overall water requirements have reduced by 60% after using recycled water from the plant for their process of chemical dying and printing etc. The group further conducted discussions on energy optimization for such plants and the role of government regulations and tariffs for promoting the adoption of wastewater treatment in industrial areas. Towards the end, the team of Hisaar Foundation thanked the operations team at the plant and Ms. Amber for this session and the learning opportunity it provided.