By Kefa Senoga
Waste from water to flush toilets, take a shower and do laundry is not a waste at the main campus of Uganda Christian University (UCU). It hasn’t been wasted in 17 years. It’s recycled and used to educate students, primarily those studying engineering.
UCU constructed a $300,000 wastewater treatment plant in 2006. Two-thirds of the cost of the plant, the first of its kind for any institution in Uganda, was funded by the Diocese of Sidney’s Overseas Relief and Aid Fund of Australia.
Wastewater that is generated from various daily activities is toxic to both humans and the environment, hence the need to purify it, before it’s released into the environment. Wastewater is treated in 3 phases: primary (solid removal), secondary (bacterial decomposition), and tertiary (extra filtration).
According to Arnold Mugisha, a demonstrator at UCU’s department of Engineering and Environment under the Faculty of Engineering, Design and Technology, the wastewater treatment plant that was developed by Prof. Steven Riley, uses a biological process to treat the sewage and clean the water so that it is safe enough for disposal into the environment.
Mugisha says that the plant uses an activated biological sludge water treatment process, where microorganisms are used to break down the organic matter, which would otherwise be hazardous to the environment.
The plant has several sections, with the first having screens, where paper, pads and other similar waste are removed. The screened waste water then drops into the equalization chamber, from where the microorganisms break down the fecal matter. The water is then pumped into the aeration chamber, where more oxygen is supplied to the microorganisms, to enable them break down the waste completely.
“The waste is broken down by absorption, where the microorganisms eat the waste, and adsorption, where the organic waste sticks onto the body of the microorganisms,” Mugisha explains.
According to Mugisha, this is the most important step of the plant because that’s where most of the biological oxygen demand is reduced.
At the clarifier stage, solid particulates or suspended solids are removed from the liquid. At this point, the deposited sludge settles at the bottom and the clear water remains up, says Mugisha. The sludge is used for both manure and decomposition by anaerobic bacteria to produce biogas. At the time of installation, the plant was able to treat about 350 cubic meters of water per day.
At the chlorination chamber, chlorinated water is used to kill extra organisms that are still in the water. Mugisha says that if waste water is not treated properly, it can pollute water sources, cause illnesses and damage natural habitats. The treated wastewater is used for irrigating flowers, grass and plants in the university compound. People who would want to use the sludge for manure in their gardens are always granted permission to pick it from the facility.
Okot Innocent, a fresh UCU engineering graduate, says the facility provides a platform for engineering students to put their classroom knowledge into practice, learning in practical terms how the processes work.
“Some of the students who want to become water engineers have the opportunity to familiarize themselves with the equipment and the systems used in the treatment process,” Okot noted.
In Kampala, the Bugolobi wastewater treatment plant is the largest in the country and serves about four million people per day. The plant is capable of processing 45 million liters of waste daily.
