The Chief Operator for a surface water treatment plant (SWTP) reports that replacement of a troublesome vacuum liquid feeder for poly aluminum chloride (PACl), with a more advanced vacuum liquid feeder, ended the threat of a process upset for operations staff that was caused by the previous unit not being able to hold a constant feed rate. The ability to provide a consistent feed is needed as a key element in the plant pre-treatment process, which features turbidity reduction and clarification.
The textile industry is a water consumption intensive industry. Water is utilized for cleaning the raw material, and for the different steps in the textile dyeing process. Due to the effects of water scarcity and stricter environmental regulations, the cost of fresh water utilization has increased worldwide.
In the past several years, Aquarion Water Company had been monitoring their system’s THM formation and attempting to lower them through treatment and distribution system changes. Aquarion engineers decided that reducing THM formation in the Laurel High Service Clearwell at the Stamford Water Treatment Plant (WTP) would eliminate concerns of elevated THM formation in the distribution system served by the WTP.
In late 2005, the City of Newberg, Oregon, decided to upgrade their water treatment plant disinfection process from gas chlorine to on-site hypochlorite generation (OSHG) in an effort to simplify operations and increase operator safety. The plant produced an average of 2.5 million gallons per day (MGD), with a peak capacity of 5 MGD.
Nutrient pollution is getting worse in many estuaries throughout the United States, especially those on the heavily populated East Coast.
The Baia Mare Aurul gold mine in North Western Romania suffered a historic catastrophe in January 2000, when its dam burst, streaming out 100,000 cubic meters of waste water, largely contaminated with cyanide, commonly used in the process of mining gold, into tributaries of the Tisza River, a major waterway in Hungary.
The cities of Littleton and Englewood, CO, just south of Denver, share a wastewater plant — the Littleton/Englewood advanced wastewater treatment (AWT) plant located in Englewood. The 7886 m3/hr (50-mgd) Littleton/Englewood AWT plant serves more than 300,000 residents in the Denver metropolitan area. The facility also receives sewage from 21 districts within a 75 square mile service area. Plant effluent is discharged to the Denver metro area’s major watershed, the South Platte River.
Arlington County’s Water Pollution Control Plant (WPCP) in South Arlington, VA, is located on 35 acres of land squeezed into a commercial/residential neighborhood less than a mile west of Ronald Reagan Washington National Airport. The facility treats flows from nearly all of Arlington. In addition, nearly 20 percent of the plant’s flow comes from neighboring localities such as Alexandria, Fairfax County, and Falls Church. Effluent from the plant is discharged into Four Mile Run to the south, which feeds into the Potomac River and, ultimately, the Chesapeake Bay.
In 2007, Greenville, SC-based Western Carolina Regional Sewer Authority (WCRSA) conducted a rigorous performance test on a new tertiary treatment technology to assess its ability to effectively remove nitrate-nitrogen (NO3-N) without using excess amounts of methanol at its Lower Reedy Wastewater Treatment Plant (WWTP).
As a result of China’s rapid economic development in recent years, the country has implemented more stringent environmental standards. Local environmental protection departments now require most urban wastewater treatment plants (WWTP) to apply strict enforcement measures to meet Class IA effluent discharge standards according to the Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant (GB18918-2002).
In an effort to lower operational costs and extend the life of the dewatering centrifuge, operators in Springboro, OH, began to look at the polymer activation equipment in use at the plant. The Polyblend® M-Series emulsion polymer activation systems had been in steady operation for over 10 years. The equipment still performed reliably, but operators were interested in ways to achieve greater efficiency. They were aware of the new Polyblend® Magnum mix chamber, with its enhanced two-zone mixing energy.
The Hagerstown Wastewater Treatment Plant in Maryland incorporated several plant modifications, one of which was the conversion of their disinfection process from the use of ozone to UV.