AWWA MTC69670

Increases in the population of the City of Ormond Beach, Florida (the City) placed increased demands onthe City's existing 8.0 mgd conventional lime softening WTP. Coupled with the anticipated deteriorationof raw water quality due to the intrusion and upconing of salt water, the City requested CDM to conduct apilot study and complete the preliminary and final design for a 4.0 mgd low pressure reverse osmosis (LPRO) expansion. Final designwas completed in 2006, construction activities for the LPRO expansion commenced in 2006, the systemwas placed online in 2007, and all construction activities concluded in early 2008. A collaborative effort by the City, the FDEP, and CDM resulted in the successful permitting of aninnovative and sustainable method of disposing of up to 1.0 mgd of concentrate produced by the City'sLPRO expansion. This unique method of concentrate disposal provided for the blending of the LPROconcentrate with reclaimed water at the City's WWTP. The most significant benefit associated with theimplementation of this disposal method includes the ability to reuse this previously unutilized resourceand augment the City's reclaimed water supplies. Furthermore, no portion of the City's WWTP capacitywas consumed, as concentrate blending occurs in the equalization basin downstream of all treatmentprocesses.The past seven months of operation demonstrate the success of this innovative and sustainablemethod of concentrate disposal. Blending the LPRO concentrate with the City's reclaimed water hasincreased the City's supply of this resource by approximately 0.5 mgd. While the use of reclaimed wateris heavily affected by the amount of precipitation, approximately 80 to 90% of the LPRO concentrate isreclaimed, and during periods of high reclaimed water demand, 100% of the LPRO concentrate isreclaimed. While the TDS and chloride values of the blended reclaimed water have increased as a resultof concentrate blending, no adverse effects to the vegetation or soil structure have been observed.This paper discusses the permitting efforts and challenges associated with the implementation of thisinnovative method of concentrate disposal. Includes tables.

Product Details

Edition:

Vol. - No.

Published:

11/01/2009

Number of Pages:

11

File Size:

1 file , 1.2 MB