Polyprod-logo.jpg (6934 bytes) Evaporative Tank™ Series

Atmospheric Evaporators

 For Dragout Recovery & Wastewater Reduction

pp-1.jpg (17125 bytes)


pp-2.jpg (12584 bytes)

1.Ball Valve 2.Evaporative Panels (ET II & ET III only) 3.Drain 4.Deflector Panel 5.Mist Eliminator

Evaporative Tank™ Series

The EVAPORATIVE TANK™, free of complicated machinery and chemistry, was developed as a cost-saving means of recovering valuable dragout. Our plating customers have doubled their benefits by using the EVAPORATIVE TANK™ for E.P.A. compliance and discovering dramatic savings in their waste treatment costs. The EVAPORATIVE TANK™ has also found new uses in the anodizing, painting, photographic, machining, chemical and other fields. This proven, simple and inexpensive system of recovery and reduction can pay for itself in as little as 30 days.


The EVAPORATIVE TANK ™ is available in four models; the ET-II and the ET-III are designed to recover chemicals (dragout) from rinse water.

The ET-II-W and ET-III-W are ideally suited for dewatering spent solutions or wastewaters that may have a high solids content.

 Pumped solution is circulated at a high rate from your process tank or reservoir up to the ET-II-W or ET-III-W and is drained back by gravity to your tank. In the evaporator, the solution is sprayed onto 700 or 1,000 square feet of evaporative panels to humidify the blower air that is forced through these panels. The humid air is then ducted to the outdoors. Heat for evaporation is taken from the solution pumped through the evaporator(about 9,000 BTU per gallon of evaporation.) The "triple-effect", proprietary mist eliminator reduces any droplet emissions to a very low level. An optional AirScrubber™ can be installed inside the EVAPORATIVE TANK™ at any time to further reduce emissions to meet most stringent regulations.

The ET-III-W or the ET-II-W depends on a high flow rate and large solution drops suspended in the air stream for its extensive evaporative surface. The 1/2" passages in the spray nozzles make the ET-III-W ideal for waste minimization. The ET-II-W is a smaller version of the ET-III-W and uses a flow rate of 20 to 25gpm.

The chart at right is based on evaporating pure water at 0% relative humidity.  As the impurities in the water increase, there is less water available to evaporate; your evaporation rate will decrease. As relative humidity increases, the evaporation rate of the solution at ambient temperature decreases. As solution temperature increases, the effect of relative humidity on the evaporation rate decreases. Temperature does not dictate evaporation rate ... BTU input does (9,000 BTU's or 2.6 KWH per gallon is needed to maintain solution temp.). This graph shows the maximum evaporation rates you can expect. Every application is unique, and solutions are not pure water at 0% relative humidity.

Pat. # 4790904 

See below for heated tanks system with higher rates.

pp-3.jpg (15800 bytes)

Benefits of the EVAPORATIVE TANK™


Natural evaporation uses no resins, membranes or electrolytic plate-out cells that require high maintenance and replacement costs. Since no chemistry is added or removed, your process remains unchanged.

Low Maintenance

The EVAPORATIVE TANK ™ uses only two moving parts - a pump and low cost blower. All molded polyethylene components for solution security, the tank thickness is approximately 1/4" to 3/8". Other materials used are high-temp CPCV, polypropylene, PVC and stainless fasteners. The EVAPORATIVE TANK™ is the ONLY atmospheric evaporator with a lifetime no-leak warranty.

Low Cost

Totaling all costs: initial purchase, energy, maintenance - the EVAPORATIVE TANK ™ is the most cost effective in recovering 100% of the chemicals (dragout) from your rinse water, or in reducing the volume of spent solution and wastewater. Energy costs to evaporate solutions (water) are calculated as 9000 BTU or 2.6 Kw  / per gallon / per hour.  Example- if Kw is $ 0.05, then the cost to evaporate one gallon of water is (1 gallon) x (2.6 Kw/$ 0.05) = $ 0.13 per gallon 

More Details - Applications   - Installation methods

pp-9.jpg (16154 bytes)pp-5.jpg (12626 bytes)

ET-Companion Condenser ™
pp-6.jpg (12998 bytes)
When installed with an EVAPORATIVE TANK™, the ET-Companion Condenser ™ removes water from the evaporator's air exhaust. The dry air is returned to the EVAPORATIVE TANK™ to work again. 

No more holes in your roof for exhaust ducting. No need for permits from air quality people; this is a completely closed-loop air system.

Recovers all water that is evaporated. Today's regulations require recovery of resources wherever possible. It makes economic sense, and removes the need for permits. Reuse your rinse water.

Eliminates the air make-up problem. The same air is used over and over again. No need to heat or air condition replacement air - saving thousands of dollars.


Heated Tank System 
pp-10.jpg (12277 bytes)
Heated Tank Evaporator System ™ shown with the ET-Companion ™ Condenser - Provides rates up to 160 GPH

The Poly Products Evaporator System evaporates water from process solutions and waste waters under atmospheric conditions. The highest evaporation rate can be achieved by heating the solution prior to pumping it into the evaporator.

This is accomplished by using our heated tank with either a gas-fired burner, steam coil or electric heater. The patented (#4790904) ET Evaporative Tank ™ is molded out of polyethylene, with no weld seams, for leak-free operation. With over 2,000 products in the field, the Poly Products evaporator has proven to be the leader in atmospheric evaporation of water.

 Systems Includes: •Evaporative Tank ™ •Stainless steel heated tank and fire tube (carbon steel and polyethylene are also available) •Gas fired burner, steam coil, or electric heater •Control panel with temperature control, over temperature protection and level controls for automatic operation •CPVC or stainless steel centrifugal pump to feed evaporator •Skid mounting with piping and wiring installed at the factory

** MINI series does not include platform and stand.

 Optional Accessories: •ET-Companion ™ Condenser for recovery of the evaporated water for reuse •Insulating the heated tank •Filter press for continual solids removal •Storage tanks •Pump stations •Cooling tower for ET-Companion ™ Condenser cooling water •Above dimensions can be altered to fit special installation requirements

Control panel for heated tank system ET-Companion ™ Condenser for closed loop recovery of water and plant air

Filter press with polypro plates for solids removal ranging from .5-100 Skid.ft. capacity

Heated tank with gas fire tube: How the Evaporator Tank Works


This equipment is warranted by Poly Products Inc., to the original user for one year following the date of purchase against defects in materials or workmanship when installed and operated according to our instructions and limitations , and when used with approved solutions. We will, at our option, repair or replace any part or assembly proven to be defective when it is returned prepaid to our plant. fans and metal parts (i.e. motors, etc.) are not warranted against corrosion. This warranty is in lieu of any others. We assume no responsibility for consequential damages.

Return to KTH Home Page