CV WATER FILTRATION
Water is a valuable resource and every year it is becoming a greater challenge to bring down the cost of maintaining process water. In the not too distant past, the process water was sent to the drain with little concern of the cost of replacement.
Finding the best way to extend the useful life of any process water is an important endeavor that relates directly to reducing or eliminating discharge fees for compliance, maintaining high production and quality, staying competitive and being environmentally aware.
Today, the stringent regulations for ppm of any number of metals and other contaminants in the process water adds greatly to the production cost and in relation to this article, the process water is used for cable insulating by continuous vulcanization, CV water.
Filtertech is continuously improving all liquid solids separation applications in the wire industry worldwide.
The CV water application is one that the sub-micron material in the water cannot be removed by conventional mechanical filtration methods alone such as Ultra Filtration, Plate and Frame Filters, sand filters or similar devices. However, CV water maintenance is particularly suited to a new, continuous filtration process developed by Filtertech using a dry separation chemistry.
After extensive testing with CV water samples and dry separation chemistry, a formulation was developed and successfully proven in our lab.
As seen in Figure 2, a side stream system is designed to continuously remove the contaminants from the CV water in a controlled manner. A typical system includes supply and clean return pumps, a volumetric “dry separation chemistry” feeder, two reaction tanks with one high speed mixer, one low speed mixer, and a Filtertech GSF Gravity Filter. System control devices such as flow meter, feeder speed control and variable speed mixers allow adjustment for production increases and slow down cycles.
The CV water is delivered to the first tank where the dry clay chemistry is introduced by the volumetric feeder. The higher variable speed mixer disperses the chemistry and the retention time of the tank assures good saturation as the separation begins. Positive displacement transfers the water to the second tank with a low variable speed mixer and the predetermined retention time allows the flocculent to be fully established. The “floc” produced is a combination of the different contaminants in the water. The mixers and continuous flow transfer the floc and water to the Filtertech GSF gravity filter for final separation and disposal.
The result is dry floc solids captured on the filter media and very clean water returned from the GSF Gravity Filter to the CV water process at desired clarity levels. The clean CV water can either be retained for reuse or sent to drain, if necessary
Preliminary Lab and Pilot Testing
Filtertech offers free preliminary lab testing of the CV water with a test report showing actual contaminant removal percentages. A pilot testing program has been developed for North America to confirm application feasibility. Based on pilot system availability, actual on site operation will qualify lab results to real time observation.
Other Similar Applications
Using the same dry separation chemistry technology, a different process water application that has been proven worldwide is caster water filtration.
In the process of continuous casting copper rod with a wheel type caster, acetylene soot is applied to the caster wheel and band as a release agent and insulator while optimizing heat transfer. Figure 4. The amount of soot that remains in the water is critical to the process and relates directly to line speed, component life and product quality.
The Filtertech Caster Water Filtration System maintains precise levels of soot in the water and collects the excess soot flocculent on the filter media for disposal.
With 16 active systems worldwide, significant and continuous cost savings have been realized with full amortization of several projects in less than 12 months. The multiple benefits include:
Increase in rod production
Improved rod quality
Reduced hollow bar breaks
Fewer down-stream wire breaks
Longer caster wheel life
Longer band life
Less heat exchange or cooling tower cleaning
Fewer high pressure pump rebuilds
“0” blow-down water discharge
Caster Water Systems have also been supplied for Contirod Installations or copper rod production using a Hazelett Twin Belt Caster. Water is used to transfer heat from the twin belts and dam blocks. Graphite is used to lubricate the caster dam blocks and it migrates into the water and must be controlled to reasonable levels. The same significant results found with the wheel caster application can be realized in twin belt rod casting as well. The continuous removal of graphite and associated process contaminants using the caster water filter system will improve water heat transfer from the belts, increase production rates and improve rod quality while keeping dissolved copper levels in the water lower.
The CV or caster water filter systems are compact and modular designed for economical container shipping and ease of final installation anywhere in the world.
Filtertech is committed to providing the most innovative solutions to real process issues. We will work hard to provide what the industry is looking for, high returns on equipment investment for our customers through lower initial costs, years of trouble free service and continuing savings in improved processes.