A recycle water system was shipped by Vooner to a new mill location in fall 2008. This eco-friendly system will assist the new facility in improving vacuum dewatering. The new mill will be able to use recycled water for cooler seal water to vacuum pumps. The system includes a Cooling Tower and an Osprey™ Gravity Strainer to allow the mill to recycle water with ease. According to mill managers, the thing that stood out about the new system was that it was “Easy and Inexpensive to Install.”
Going into spring and summer the temperature of vacuum pump seal water starts rising if it is recirculated. The water temp can reach 140°F but with the cooling tower the temperature is reduced to 80°F. A major benefit for the paper machine dewatering is that the lower seal water temperature improves the vacuum pump capacity by about 10-15 percent. Also, the new cooling tower can reduce water costs and sewer taxes by as much as 97%, with these savings the system can be paid for in less than 6 months.
To keep the customer’s water temperature from rising during recirculation, the mill purchased a cooling tower designed to cool 600 GPM of seal water from 140°F to 80°F. The tower contains (6) high efficiency 10hp fan motors and propellers. The Tower also includes an aluminum ladder assembly; safety cage; upper safety handrails; internal grating/walkway; vibration cut off switches for motors; and PVC internal piping.
Also, the mill had concerns about maintenance problems from fiber buildup on the fill within the tower. In order to meet their needs CVN Vooner was able to provide the solution of a “fill-less” cooling tower. This design was a new concept for Vooner and will be offered for future customers to take care of maintenance worry.
In determining the needs for the recirculation of water, the mill also ordered the Osprey™ Gravity Strainer. The Osprey™ Strainer allows the fiber contaminated vacuum pump seal water to be cleaned and recycled for continuous use.
The Osprey™ Gravity Strainer located ahead of the cooling tower removes fibers and other debris separated with a fine mesh wire screen. The Osprey™ gravity strainer is constructed completely of 316L stainless steel.
The major benefit of the Osprey™ is its patented automatic self-cleaning design allowing continuous cleaning without labor intensive periodic hand spray back wash cleaning. The internal spray arms’ water flow is 66 GPM, has many self-cleaning fan nozzles, and has an adjustable rotating speed range of 5-16 RPM. The mill’s Osprey™ was designed for a water flow rate of 2,000 GPM (600 GPM for seal water) with a solids density of 250 PPM. This Osprey™ was approximately 6,500 lbs and is one of the largest that Vooner has designed and manufactured.