\[#Cuatro Comunidades\] \[#Tamara\] \[#Ojojona\] |
Thursday 5.14 we spent nearly the entire day at the plant. Dan was testing out his turbidity and data-logging equipment, John and Wil were trying out wooden covers to seal off ports in the canal that lead to the sed tanks, and Antonio took advantage of the day to clean the plant with the plant operators.
The idea of sealing the square ports with wooden covers did not work well. Even with a gasket made from an old rolled-up inner tube, the wood covers did not seal well at all. The concrete sockets appear to be too rough and uneven to make a good seal. We weren't even able to accumulate 2 inches of water in the channel before water started quickly leaking through into the sed tank we were trying to seal off. Because we see very little possibility of the covers working, we are exploring other possibilities. We are thinking of returning to PVC pipe fittings. Rather than making the entire chimney from PVC pipe, we could just set a short PVC socket into the top of the chimney and seal off that socket with a short nipple of PVC pipe. We plant to attempt these changes during the dry season when the plant can be bypassed for a week or so. In the meantime, when the operators clean the sed tanks they will clean both at once.
Antonio emptied and cleaned the entire plant with the operators. In this process, we realized that quite a bit of thick mud is accumulating in the bottom of the sed tank inlet manifolds (sorry did not have the camera and do not have photos). We assume this is due to flocs settling in the manifolds. When the tanks were emptied, the slope at the bottom of the manifold toward the center of the tank was not enough to push the mud out of the manifolds. Once the tanks were empty, opening up a manifold revealed a cap of mud about 4" deep. What we don't know is whether this mud is obstructing the ports where the water comes out the bottom of the manifolds. Such obstruction could account for the high upflow velocities we were observing in the near end of the tank. We were hoping that the flow of water would keep the ports clear. It is hard to tell where the mud is when the tanks are full by looking at them when they are empty.
Because the pressurized hose had still not been hooked up to the plant entrance and we were in a hurry to get the plant online because the community was without water, we did not attempt to clean the mud from the inlet manifolds. However, we will need to do this cleaning within the next couple weeks before the mud begins to solidify even more.
Monday 5.18 we will meet with the water board to make final plans for the June 6 inauguration. We are in the process of inviting many important figures, including the mayor of Tegucigalpa and the director of SANAA, and are hoping for AguaClara's biggest inauguration yet.
The chemical barrels in Tamara continue to leak. One chlorine barrel and one alum barrel leak so much that they are no longer used. We need to find a solution to this problem. We are considering building brick chemical tanks like in the Cuatro Comunidades trying to repair the existing barrels. The brick tanks are tempting but we still have not found a reasonably-priced product to protect cement from the acidic aluminum sulfate.