How To Clean Scale From a Heat Exchanger
ScaleBreak chemcial descaler quickly removes deposits like lime, scale, and rust that otherwise drastically reduce efficiency, increase expenses and damage to vital components.
For the fifth installment of Cleaning With ScaleBreak®, we are outlining the steps for cleaning shell & tube heat exchangers with ScaleBreak.
When cleaning a shell & tube heat exchanger you will first need to visit our calculation tool at www.goodway.com/resources/calculators#!/shell-tube-menu so you know the proper amount of ScaleBreak needed and how long to perform the circulation. The information in the calculation tool allows you to adjust the amount based on the thickness of scale in your exchanger.
- Isolate the heat exchanger from the system by closing the supply and return water valves.
- Position a ball valve on the low point of the heat exchanger. This valve will function as your entry point for your ScaleBreak cleaning and can be closed to prevent backflow.
- Attach your circulation hoses so you are pumping into the bottom of the heat exchanger and returning the fluid out the top.
- Your exit point on top needs to be at the highest point of the exchanger. If tubes are above your exit point, position the hose at a higher point. This action will bring up the liquid volume and ensure the higher tubes are flooded and do not become air bound with CO2 or foaming resulting from the cleaning.
- Fill your exchanger with water and perform a hydrostatic test by turning on your pump and circulating water. This action assures the exchanger is isolated and none of the ScaleBreak will be needlessly lost.
- You will need to bleed off enough water equal to the volume of ScaleBreak required for the cleaning. If you relieve too much water, you can add some back in to complete your recirculation loop.
- Water formed deposits will occupy volume, as a result, additional water may need to be added during the cleaning duration as deposits are dissolved.
- Periodically check your isolation valves as they may have initially seated against scale. As ScaleBreak dissolves the scale, this action will help you avoid losing product.
- Circulate the ScaleBreak solution for the recommended timeframe as indicated by our calculation tool.
- During your ScaleBreak cleaning, you will want to make sure your solution remains active. For this step, please follow our “Testing ScaleBreak’s Effectiveness” procedure.
- Once you have reached the recommended circulation time and your ScaleBreak solution has completed the job, you can begin your flushing process.
- Though ScaleBreak is a biodegradable solution, most facilities need to conform to pH discharge limits. ScaleBreak Neutralizer can be utilized to safely elevate your pH to meet your discharge limit so it can be flushed to the drain. Please follow the instructions for this process in the ScaleBreak Neutralizer information sheet.
- To flush your heat exchanger, turn off your circulation pump, remove the return hose from your recirculation system and put it in a drain.
- Add a freshwater hose to your recirculation bucket on your pump system and turn the pump back on.
- Continue running clean water through the heat exchanger for 10-15 minutes or until the return water is running clear. This action will also flush your pump system.
- Disconnect your hoses, close the valves you performed your circulation through and open the valves for the exchanger supply water.
- Your heat exchanger can now be returned to service.
This procedure is for off-line cleanings only, please contact Goodway Technologies for instructions to perform an on-line cleaning.
- Follow all local regulations for discharge.
- Follow all plant personal protective equipment guidelines as determined by your health & safety team.
- ScaleBreak formulas have very minimal corrosion rates, however, the application of ScaleBreak may reveal pre-existing under-deposit corrosion (UD). This type of corrosion can present itself in the form of pitting, pinholes or similar types of damage.
Contact us with any questions.