Application of aerated biofilters for production of high quality water forindustrial reuse in West Basin

The results of 5 years operation of 8 full-scale up-flow aerated Biofor(R) biofilters, installed at the West Basin Recycling Plant treatment plant (Ca lifornia), demonstrated the efficiency and reliability of this technology i n the production of high quality ammonia free water for industrial reuse as cooling water in ail refineries. High nitrification rates up to 0.75 kg d( -1) m(-3) (0.047 lb d(-1) ft(-3)) were obtained at water velocities of 6.7 m h(-1) (867.5 gpm). The hydraulic retention time in the biofilters was sho rt without any negative consequences on the process. During all five years of operation, all Biofar(R) units demonstrated very reliable performances w ith 100% ammonia removal efficiency and very low residual suspended solids concentration of about 4.0 mg TSS L-1.