At 9.15 a.m., we had a meeting with the operators. Before the end of the meeting, as today is the last working day of 2016, Tee thanked the operators for their cooperation and contributions to the team throughout this year.
At 10.00 a.m., I conducted pipeline tracing in the DPRS site to be fully familiar with the flow and location of each equipment.
At 11.30 a.m., Tee asked me to do the calculation of the amount of chemicals required for the flocculation and coagulation using a jar tester. I am planning to understand the information of the jar tester in advance.
At 11.45 a.m., I went to WWTP to observe the existing DAF unit. Jaclyn and the operator Desa were monitoring the water condition in the flocculator. They managed to obtain a clear solution with floating flocs when adding the flocculants (polymers) into a bottle of water sample taken from DAF influent, but the same result was not shown for a water sample taken from the flocculator after the chemical dosing. Eventually, they managed to get the same outcome after several trials and errors.
At 3.00 p.m., I met Tee and Jaclyn in the WWTP control room. Tee conducted a simple experiment with a water sample taken from a sludge recirculation pit to observe various types of microorganisms using a microscope. He showed us the bacteria and metazoan such as rotifer. I had an opportunity to observe the rotifer swimming freely, using a microscope.
The rotifers are often found in extended aeration-activated sludge (EAAS) systems with older sludge. Their principal role in wastewater is to develop floc stabilization. Their presence indicates a good, stable sludge with plenty of oxygen. Rotifers are good indicators of wastewater toxicity as they are sensitive to toxic loads, however, they should never be dominant in the system.
At 4.00 p.m., Jaclyn and I went to the DPRS site. At the same time, the construction of a new above-ground pipeline is carried on to replace the old, broken underground pipeline.
Reference:
Rotifers. [online] Available at: http://www.environmentalleverage.com/Rotifer.htm
[Last Accessed: 2 January 2017].