A New Approach to Evaluating the Performance of a High-Rate IFAS Treatment System

Council Bluffs Water Pollution Control Plant
Council Bluffs, Iowa

The Council Bluffs Water Pollution Control Plant (WPCP) added a high-rate, integrated, fixedfilm,
activated sludge (IFAS) process in 2007 to increase the organic removal capacity of their
conventional trickling filter plant. Plant staff uses an innovative approach to estimate the fixed
biomass on the IFAS media through strategically placed miniature textile-media coupons. These
coupons were used to evaluate the performance of the high-rate IFAS system at design
conditions during cold-weather operation in 2009. Results showed that the system could operate
within permit limits at design conditions; however, the effluent quality was less than predicted
target values. Results also showed that the average IFAS media biomass loading was only 40%
of the manufacturer’s design value. Additional testing is needed to evaluate options for
improving effluent quality at design conditions such as increased mixed liquor, increased solids
retention time (SRT) or even increased hydraulic retention time (HRT).
KEYWORDS: Trickling Filter; Integrated, Fixed-Film, Activated Sludge; IFAS

Metric Used:
Posted: May 20th, 2011 | Filed under: 50k-100k, Waste Water Treatment | Tags: Achieve Permit Limits, Improved CBOD Removal, Increased Plant Capacity | No Comments »

---