(56d) Granular Ceramic Media Comparison to Traditional Sand/Anthracite Filtration and Granular Activated Carbon Filtration in a Drinking Water Treatment Plant

The Birmingham Water Works Board conducted a three-phased evaluation of granular ceramic filter media in its pilot plant. The pilot plant contains two full treatment skids and has a SCADA system that logs all of the online instruments every 10 minutes. The online instruments are feed pumps, flow meters, particle counters, pH probes, turbidimeters, SCM, and TOC analyzers. The first phase looked at the performance of ceramic filter media against GAC filters, and Sand/Anthracite filters. There were four different mesh sizes available for analysis 14/30, 20/40, 40/60, and 70/80. Eight different conditions were tested before moving on to the next phase of analysis. Filter performance was based on effluent turbidity, run time before reaching six feet of head loss or effluent turbidity ?d0.1ntu, uv254, particle counts, and organics removal. Once the first phase was completed, the second phase took the ceramic media condition with the best performance in the first phase, and installs that condition in one filter per skid in order to compare its performance against GAC and Sand/Anthracite filters during the testing of new treatment conditions. The new treatment conditions were tested with changing coagulant pH, different coagulant chemicals, various coagulant polymer aids, different flocculant aids, different filter pH's, and filter aids. Organics removal will be based on the results of TOC, and uv254. DBP formation potential tests will be performed as well. Phase three operated the two ceramic filters as a pre-filter for the raw water tanks in order to determine organics removal, filter performance as a pre-filter, and the effects it will have on turbidity, coagulation, flocculation, sedimentation, and filtration processes. This pre-filtered water was fed through one skid and treated, while normal plant matching conditions were on the other skid. This provided a direct comparison allowing for determining if there was any benefit in operating the pre-filter process. The literature search for this media yielded two studies, but the scope of the analyzed performance was limited. Two studies, using gravity filter applications, have been performed in Waco, Texas and Frankfort, Kentucky. The Kentucky study could not accurately determine filter run performance because the studies began and ended when workers were present to operate the test. The Waco, Texas studies allowed the filters to run until a certain effluent turbidity was achieved, a maximum level head loss, or a specified run time, but nothing was analyzed as far as the media's ability to perform under varying treatment processes while being compared to traditional Sand/Anthracite filters and GAC filters undergoing the same varying treatment conditions.