A precision analyzer has reduced the time and complexity of measuring trihalomethane (THM) levels in drinking water at U.K. water utility Anglian Water. Capable of analyzing samples in less than 30 minutes with no reagents or sample preparation, the instrument has been supplied by the Instrumentation Products Div. of Parker Hannifin.
Anglian Water is the first water company in the U.K. to install the technology. During the last five years, the company has invested more than £100 million in drinking water improvements, surpassing some of the most stringent quality targets in the world. In July 2015, Anglian Water made the decision to install an in-house THM sample monitoring and analysis system.
In England and Wales, water supply regulations enforced by the Drinking Water Inspectorate (DWI) set a maximum limit of 100 µg per liter for total THM concentration. Water supply companies therefore closely monitor THM levels to ensure compliance with this regulatory limit and maintain water quality and safety.
Until now, like many water supply companies, Anglian Water has relied on a laboratory for THM analysis. This involved sending samples to the laboratory and waiting for the results. Anglian Water therefore decided to look for an alternative onsite method, which would take pressure off its laboratory and deliver a same-day result.
The THM analyzer that Parker supplied is an integrated purge-and-trap system connected to a compact gas chromatograph column and a sensitive surface acoustic wave (SAW) detector. It provides a completely self-contained solution for real-time measurement and analysis of THM concentration levels, down to as low as 1 ppb for each individual species of THMs. The analyzer can measure chloroform, dichlorobromomethane, dibromochloromethane and bromoform—the four species that make up total THMs—to within 10% accuracy.
“Using the Parker THM analyzer we are now able to measure THM concentrations in-house, and in less than 30 minutes,” said Mark Berry, innovation project manager for Anglian Water. “We are currently analyzing over 20 samples a week and have found the system to be very easy to use. Aside from the potential cost-saving benefits, the much faster analysis capabilities provide scope for further improvements in operational efficiency.”
Parker supplies the THM analyzer as a complete turnkey package. The company’s Veriflo Div. manufactures the high-purity pressure regulators and precision control valves for its helium carrier gas system.