In the late 1990s, one western Pennsylvania sewage treatment plant (STP) sought to process Class B biosolids on-site, eliminating the expense of hauling liquid off-site and significantly decreasing associated labor costs. At the same time, the plant needed to achieve higher cake solids and provide strict odor control. In addition, the selected equipment also had to be able to greatly enhance process efficiencies at not just the one plant, but its sister facility as well. Fortunately, USFilter offered a fairly simple solution to meet the STP's seemingly complex needs.
Robert W. Mau and Dean Clemons
Ann Arbor, a densely populated university town of 180,000, has been seeing an increase in urban redevelopment pressure in recent years as developable land has become scarce and land values have risen. The city of Ann Arbor has worked closely with the County Drain Commissioner’s office to use this redevelopment as an opportunity to improve the quality of stormwater flowing into the county drains.
Since the passing of the Clean Water Act, the industry has made great strides in improving the quality of point source discharges to the environment. As treatment technologies continue to improve, non-point source pollution becomes a more significant contributor to environmental degradation.
Based on the City of Hollywood’s experience, the use of 316L stainless steel should be evaluated carefully due to the potential for problems in the erection and construction of water treatment facilities that will be in contact with high chloride water and/or other corrosive chemistries. As with many membrane facilities, much of the stainless steel is exposed (not buried), which subjected it to atmospheric as well as water quality problems. Therefore, unless the quality control of the raw and reject water (chemical, physical and microbial) can be assured, 316L stainless steel may not be the appropriate material for engineers to specify.
Drinking water treatment professionals have long held fast to the belief that granular activated carbon (GAC) based on bituminous coal provides the best performance for their demanding application. That’s why, when an article in 1999 cited evidence that a lignite-based GAC outperformed a bituminous-based carbon, industry experts were surprised and more than a bit skeptical.
Fresno Discovers Big Difference Between Reagglomerated Carbon and Direct Activated Carbons
At the Procter & Gamble manufacturing plant in Greensboro, N.C., an Aquionics ultraviolet (UV) dechlorination unit was installed before two banks of reverse osmosis (RO) membranes. Trials that ran soon after the UV system’s installation showed a dramatic reduction in the RO membrane wash frequency—down from an average of eight cleanings per month to only two per month.
Reverse Osmosis Membranes Maintenance Costs Reduced
challenges are emerging in the industry that require new methods and product
developments. This article discusses additional test methods for the AC
ASTM, AWWA and EPA Standard Methods and New Test Methods for AC
Since the 1960s, municipalities and industries have used packaged water treatment plants to successfully and economically treat small water supplies. These packaged plants have offered a smaller footprint, lower capital cost and easy operation.
The future of safe drinking water lies squarely in the hands of the point-of-use (POU) water purification industry. Growing awareness among decision-makers and consumers is the force behind the increasing importance of the POU industry.
Membrane technology offers the possibility of managing total water resources. The spiral wound membrane element configuration is the most widely used due to its high packing density and relatively low price. This article will describe some technological advances in the area of innovative new membranes and application concepts for spiral wound membrane elements.