Wednesday 2:30 PM

Room: Sapphire

An Operational Analysis of a New Lime Storage and Feed System

Selecting the method for slaking and slurry delivery have long lasting impacts on the water quality, operability and maintenance of the plant for its lifetime. This paper will describe the designed lime storage, slaking and feed facilities, operation of the system and enhancements incorporated, both physically and operationally, after four years of continuous use. The Platte West Water Treatment Plant (PWWTP) is the Metropolitan Utilities District of Omaha's newest water treatment facility. The PWWTP has a maximum day capacity of approximately 100 mgd and was completed in 2008 as the third plant in the District's "Triangle of Reliability." The designed lime storage system consists of an enclosed truck unloading bay, four unloading bins and a pneumatic lime conveyance system to transport the lime to one of three storage bins with 640 tons of total storage.The slaking system, manufactured by RDP, includes screw feeders, slaking tank, grit removal and slurry aging tanks. The feed system consists of redundant mining duty centrifugal pumps, pressure controlled valves to maintain system pressure, and control valves and flow meters to dose lime at each solids contact basin. Overall the system has functioned well for the first four years of operation, thanks to several operational enhancements and excellent maintenance. These enhancements and continued maintenance will make this essential and complicated system operational for many years to come.

Moderator:  Ben Finnegan


Eric Berggren - HDR Engineering, Inc.

Mr. Berggren is HDR’s Illinois Water Program Manager with fifteen years of engineering experience in the areas of municipal water facility design, wastewater treatment facility design, industrial wastewater and stormwater pumping and management. He has served as project manager and engineer on a variety of water treatment plant projects ranging from 1 to 160 mgd in capacity.  Mr. Berggren is a graduate of the University of Nebraska-Lincoln.