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Two parallel sedimentation tanks are connected in series with the flocculator at the pilot plant. The sedimentation tanks allow us to further examine the efficiency of the process in the AguaClara design. Sedimentation tank design needs to be optimized to acheive our overriding goal of consistent production of water, under 1 NTU. Testing will include not only the traditional lamella design of sedimentation tanks but also the alternative floc blanket based sedimentation tank designs. These two processes are being tested side by side in parallel sedimentation tanks. One tank combines of lamella and sludge blanket technology and is compared to the other which only uses a sludge blanket to treat water.
There are several concerns with the implementation of floc blankets into the AguaClara treatment plants. Some of these include: the length of time it takes to develop a fully functional floc blanket, the reliability of the floc blanket, and when and how excess sludge in the floc blanket is drained. To read more about these concerns, click here. One of the huge benefits to the pilot plant as opposed to a regular research lab is that water source is natural! The incoming water is taken from Fall Creek and therefore contains natural organic particles. This enables influent conditions to be more representative to those in Honduras.
One concern when implementating a floc blanket into the AguaClara treatment plants is the length of time it takes to develop a fully functional floc blanket. The water that goes through this sedimentation tank probably has a high turbidity during the formation period. It needs to be determined how long this could take, and explore the option of using a combined floc blanket and lamella design to continue sedimentation when the floc blanket is not fully functional. Another issue is the reliability of the floc blanket. If there is a period of time when either the influent water is clean, or for some reason alum is not being added, it is important to know if the floc blanket will be able to sustain itself, or what might happen. If the floc blanket does not sustain itself, and a new floc blanket has to be created, then this could make a substantial period of time when the sedimentation tank is not producing clean water. This is also a reason that a combined floc blanket and lamella tank may be superior.
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