Wastewater Treatment Process at WU
The wastewater produced by WU from all sources, including showering, cleaning equipment, washing, toilets, or others, will be sent to the wastewater treatment plant with consideration of environmental impacts and the livelihood of local residents around the campus. WU has a specific organization that is responsible for treating wastewater. The organization is the Division of Landscape Architecture and Environment, which was established in 2001 and has been active to the present.
Currently, WU has aerated lagoons with a capacity of 4,000 cubic meters per day. The lagoons are wastewater treatment processes using aerators to add oxygen to the water. Microorganisms can decompose organic matter in wastewater, which is faster than natural decomposition. This allows the aerated wastewater treatment system to effectively treat the wastewater.
The microorganisms also remove dirt in the process of biochemical oxygen demand (BOD) by 80–95%. The treatment uses the microorganisms in oxygen-rich conditions, with the lagoons aerating the wastewater. The process of decomposing organic substances is implemented efficiently. The lagoons for the wastewater treatment system at WU are designed to be biological treatment lagoons consisting of an aerated lagoon, two facultative ponds, and a wetland lagoon. WU also uses the ultraviolet sterilization system for the treatment.
The treated wastewater will undergo a water quality assessment by using the treated wastewater for rearing Nile tilapia before releasing the water to natural water sources. The water quality of the wastewater at WU must be in line with the effluent standards of the Pollution Control Department of Thailand.
- The wastewater treatment at WU has been active to the present. In 2022, WU improved the quality of treatment to be standardized and efficient. The university’s wastewater treatment can be divided based on the mechanism for removing impurities from wastewater as follows:
- Using garbage traps powered by electric motors. The waste in wastewater from all sources will be removed and then released to the pumping station equipped with submersible pumps.
- The wastewater released from the garbage traps will be released to the pumping station to be pumped to aerated lagoons. The pumping station is equipped with wastewater pumps with a capacity of 340 cubic meters. The pumps will automatically take turns in each round with four float switches.
- The wastewater pumped from the pumping station will be released into the aerated lagoons, which are 68 meters wide, 73 meters long, and 3.2 meters deep, with a capacity of 18,903 cubic meters. The aerated lagoons are equipped with 15kW low-speed floating and fixed-type surface aerators that decompose organic matter using aerobic bacteria. The aerated lagoons can reduce the biological oxygen demand values by 70%.
- The Facultative Pond 1, with a capacity of 18,217 cubic meters, can store water for 4 days using the microorganisms in oxygen conditions, reducing the biological oxygen demand values by 60%.
- The Facultative Pond 2, with a capacity of 37,752 cubic meters, can store water for 7 days using the microorganisms in oxygen conditions, reducing the biological oxygen demand values by 50%.
- The treated wastewater from the Facultative Pond 2 will be contaminated with some bacteria. Thus, the wastewater must be sterilized by the UV Disinfection System, which can reduce the number of coliform bacteria and fecal coliform bacteria to less than 1,000 MPN/100 ML and 200 MPN/100 ML, respectively.
- The wetland pond, with a capacity of 4,900 cubic meters, can store the wastewater for one and a half days. The pond is used for collecting the wastewater before releasing it to the next pond.
- The treated wastewater will undergo a quality assessment by farming Nile tilapia before being released to natural sources.
Goal 6: Clean Water and Sanitation
Goal 11: Sustainable Cities and Communities
Goal 14: Life Below Water