Produced water treatment filters

An overall removal/inactivation of 3-logs for Giardia and 4-logs for viruses is sufficient for this water treatment system. The Primacy Agency credits the slow sand filter, which produces water with turbidity ranging from 0.6 to 0.8 NTU, with a 2-log Giardia and virus removal. Disinfection must achieve an additional 1-log Giardia and 2-log virus removal/inactivation to meet overall treatment objectives. 

The Standard Plant. The results presented in Figure 9 for the standard treatment plant indicate that effective removal (85% ) of suspended solids is produced by the flocculation-sedimentation process. Filter run length, as indicated by the time it takes to reach a head loss of 250 cm, is 28 hr. Filter ripening is rapid, and essentially complete removal of suspended solids is accomplished by the Alter throughout the run. The settling eflBciency, head loss development, and filtrate quality predicted by the model are consistent with typical water treatment plant performance. 

A comparison of Figures 9, 11, and 12 reveals that the performance of the water treatment plant is affected by the solids concentration in the raw water in complicated and unexpected ways. Influent water with the poorest water quality produces long filter runs and the best filter effluent quality. The standard influent produces good filtered water quality but the shortest filter runs. Influent water with the best quality... 

In some instances, water produced by EDI with 10-18 megohm-cm resistivity can be used directly. Commonly, an EDI system is followed by a mixed-bed polishing filter in order to assure high purity. For customers EDI demineralization means lower water-treatment cost and less risk to downstream equipment and products [8,9]. 

A similar behavior of PFCs was well documented in a drinking water treatment plant in Oakdale, USA. The tap water produced in this plant, the influent water of which is contaminated with PFCs (see Chap. 3 and Fig. 10), has been monitored extensively over the past few years. From Fig. 10 it can be concluded that the short chained PFBA, PFPeA, and PFHxA are not well retained by the treatment plant. This can be seen at early 2007 and early 2009 when the PFCs break through the GAC filter. By the end of 2008, the GAC was regenerated and fresh GAC retained PFCs well for a short period of time. Other PFCs (PFBS, PFHxS and PFOS) were not detected in the treatment plant effluent drinking water. 

ABSTRACT Ultrafiltration membrane was used to treat Spent Filter Backwash Water (SFBW) of carbon filter and sand filter in a certain Water Treatment Plant (WTP). The results showed that the removal rate of turbidity by ultrafiltration was above 98%, the total bacteria count was less than 3 CFU/mL and the CODMn was about 1 mg/L. Ultrafiltration membrane ran stably when inflow flux was 60 L/(m h) and the cumulative water yield was about 1135 m after continuously running of 26 d, the reclamation rate was higher than 95% and the water producing cost was about 0.15 CNY/m. ... 

The sodium sulfate solution resulting from past desulfurisation can be filtered, evaporated and crystallised to produce sodium sulfate for sale. It is used in water treatment and for detergent manufacture as the quality from this source is sufficiently free of metals for this purpose. In the case where sodium carbonate is used the residual solution is usually neutralised with waste acid to remove any residual carbonate before evaporation and crystallisation. 

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