Laserfiche WebLink
<br />e <br /> <br />e <br /> <br />....-::: - <br /> <br />.' <br /> <br />TurnerCollie0Braderi Inc. <br /> <br />July 29, 1983 <br />Mr. Jerry L. Hodge <br />City of La Porte <br /> <br />Page Four <br /> <br />.,. <br /> <br />In the long run, the most practical solution is waste <br />sludge pumps, and we recommend they be installed as soon <br />as possible. On an interim basis, a single pump.in a <br />temporary installation would be an improvement over the <br />existing condition. <br /> <br />3. GRIT HANDLING EQUIPMENT - check hydraulics and mechanical <br />equipment design for the grit pumP. cyclone. and classifier <br />system <br /> <br />-- <br /> <br />There have been problems at the plant with overflow of the <br />grit classifier hopper after periods of grit pumping. From <br />. the grit chamber, there is a single 6-inch suction pipe <br />which splits to two 4-inch suction lines feeding the two <br />grit pumps. The grit pump discharge lines connect into a <br />common pipe which feeds the grit cyclone. The cyclone <br />overflow is piped to a drain line and into the plant sewers. <br />The underflow feeds directly to the grit classifier. The <br />classifier overflow is also piped to the drain line and <br />'into the plant sewer. <br /> <br />Wechave evaluated the hydraulic and mechanical design of <br />this system and have found it to be satisfactory. There <br />is-no apparent design problem which would cause overflow <br />of the classifier hopper. The pump suction, pump discharge <br />and drain piping are all adequately sized. The grit pump, <br />grit cyclone and the grit classifier are properly sized <br />and matched in capacity. We have considered a range of <br />possible operating conditions and have not identified any <br />design problems at any point in the possible range of <br />operation. . <br /> <br />There are several possible explanations of the cause of <br />the problem. The drain piping may be clogged or obstructed. <br />The equipment furnished may not be in accordance with the <br />specifications and approved shop drawings; i.e. wrong pump <br />size, wrong pump speed, wrong impeller, undersized cyclone, <br />undersized classifier, etc., or the equipment may be mal- <br />functioning, i.e. cyclone is clogged, classifier overflow <br />is clogged or obstructed, etc. <br /> <br />c: /- <br /> <br />.t <br />