Many industrial companies rely on accurate metering of the liquid they process through their plants. When the metering fails, so does the process. A paper mill in West Monroe, Louisiana, Riverwood International, discovered this a few years ago when operators found that existing flowmeters were unreliable.
The Riverwood paper mill uses thousands of gallons of water a day from the Ouachita River, public utilities and their own deep well to not only process the pulp to paper but to create steam to run the turbines that generate much of the electricity.
After being treated, water travels to a general usage reservoir where it either is pumped out to the mill for direct use in the paper-making process or to the regeneration units that, through further filtration and cationic regeneration make boiler water for the production of steam.
With the high water usage at the mill, it is important that the flow rate be regular and continuous. If one of the pipes is clogged in some way, then the balance in the regeneration units is upset.
"We had a particular problem in measuring the water from our deep well," said Larry Brakefield, Riverwood's electrical instrumentation supervisor for the power and recovery areas. "The water was filled with particulates and fine-matter sand. We had a batcher flowmeter in that application that worked by magnetic coupling and could not function correctly. We were continuously having to pull it and clean it because the iron particles would collect on it and we couldn't get an accurate reading."
Brakefield felt Water Specialties' flowmeters would help the mill because they were easy to install and repair and competitively priced.
"We didn't jump in head first, though. We bought one, put it in and tried it," Brakefield said. "It did so well we made a decision to go with these flow meters, and we've continued to buy and replace from that point."
These flowmeters are designed to operate with a minimum of moving parts, require no lubrication and offer corrosion resistance. The propeller meter is accurate at ±2 percent and has an operation range of up to 28:1.
"I decided to use one of these propeller meters on the deep water well application because it didn't seem to be bothered by the sand," said Brakefield. "Now we can tell instantly what's going through our units."