For freeze protection, the required concentration of inhibited glycol fluid in a system depends on the operating conditions of the system and the lowest expected ambient temperature. Dry Coolers has ability to look up the winter extreme low condition for your geographic location. Contact us to help you determine the cold temperature design point. For corrosion protection, it’s also important to consider the materials of construction, the age of the system and other variables. Your local glycol supplier representative can help you analyze the specific requirements for your system.

We strongly recommend you purchase the glycol pre-mixed and avoid the chance of adding improper diluted glycol solution to your system. 

DO NOT USE AUTOMOTIVE ANTI-FREEZE. Coolants for automobiles have inhibitors based on aluminum. Their inhibitor package is wrong for our industrial cooling systems.

The table below shows the protection from freeze damage provided by various concentrations of DOWFROST propylene glycol inhibited fluids. To determine the concentration required, select the lowest expected ambient temperature and decide whether the cooling system requires freeze protection to keep it pumpable, or burst protection to simply prevent damage from fluid expansion.

As a further measure of protection against dilution error, or unexpected cold temperatures, select a temperature that is at least 5°F colder than the lowest expected ambient temperature. If, for example, the lowest expected temperature is -15°F, select the line in the table below for -20°F. The table shows that at this temperature, a solution of 45% DOWFROST is required for freeze protection. A concentration of 30% is needed to provide burst protection at this temperature.

PERCENT VOLUME GLYCOL CONCENTRATION REQUIRED 

Source: Dry Coolers

We recommend the use of a full stream CyClean centrifugal separator to filter 100% of the cooling tower water flow.

The fan on a cooling tower draws in thousands of cubic feet per minute of outside air that contains sand, dust, insects, and fibers from vegetation. These airborne contaminants mix with the process cooling water and eventually these suspended particles find their way into heat transfer surfaces. After a period of time, these surfaces become fouled and insulated causing equipment to run hotter and replacement or repair is necessary.

By removing 98% of these suspended solids mechanically, fouling is greatly reduced and chemical water treatment and bleed from the system can be reduced significantly.

Full stream filtration protects the system from dirt deposits such as winds blowing over newly plowed fields, chunks of scale eroding from steel pipe or foreign deposits encountered by adding new piping to an existing system.

By utilizing a purge receptacle, expensive treated process water is not wasted in the purge cycle. A small continuous flow of dirt-laden process water removed by the separator is filtered and contained in the receptacle while the clean water is returned to the cooling system. The receptacle can then be isolated for easy contaminant removal without interrupting the process water flow and zero discharge to the sewer.

The key to good filtration is to provide a system where the dirt-laden water can enter the suction of the pump that discharges into the CyClean separator for maximum filtration of the system. If the solids can be kept in suspension, they will eventually enter the suction of the pump and then be filtered by the separator before they foul your equipment.

Source: Dry Coolers