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We are adding six new Wartsila’s to our system (two 34SGs and four 50SGs) and we are planning to use glycol in our cooling water systems. We’re in North Florida, so temperatures don’t get that cold in the winter (engines are designed for 10.8F).
I’ve got a few questions about the use of glycol / freeze protection for piping:
– How many people use glycol in their cooling water?
– Has anyone installed recirculation systems instead of using glycol?
– What drove the decision to use glycol or a recirc system?
– What concentration of glycol do you use in your system?
– Have you had to de-rate your units because glycol concentration was too high?
– Have you experienced any freezing of the high point vents on the radiators? (these are exposed 3’ tall ½” copper tubes for our system and we are concerned they may freeze even with glycol)-
This topic was modified 5 years, 5 months ago by
Our plant is in Northern BC, Canada. During the winter our temps get down to -45 C. We use a 60/40 mix in the LT system and a 80/20 mix in the HT system. Our engines were de-rated because of the use of glycol. After 6 years of operation we have never had a freeze up. The cooling system has an electric pre-heater and circulation pumps for when the engines are shutdown
We are in the central valley in California. We typically do not see any prolonged freezing periods in the winter, but have very warm and dry summers. We have the combined HT and LT circuits as a result and do not use glycol at all. We only add a corrosion inhibitor to our radiator water.
In our logic the LT pump/heater turns on automatically when temps outside dip below the 35F point. To date, we have been fortunate that this is all we have concerned ourselves with. We do have a combined cycle plant on the same property that is our base load plant, so I am sure there is some residual heat in the local vicinity that adds to our freeze buffer.
All of the points above are good and valid. I’d like to bring up one more point considering the use of glycol. In Eureka, we don’t need to worry much about freezing.
However, our water treatment consultant told us that it’s also important to maintain glycol levels to stunt the growth of biological contaminants in the water. And, we’ve definitely seen a difference when our levels get too low.
You may want to consult with your water treatment specialist before getting rid of the glycol completely.
We are close to the Twin Cities in Minnesota, have 34SG, 50% glycol in the combined LT and HT circuits. We are derated due to the cooling water circuit having the glycol. When it gets much above 90F we have to derate due to the fact that the radiator’s cant get rid of the heat in the cooling water circuit. Lube oil temps increase into the alarm point. We also add corrosion inhibitor.
We have (5) 34SG engines and run a 50/50 glycol mix. We can have ambient temps as low as -30°F. We are using polypropylene glycol with an organic corrosion inhibitor (non-toxic). We did experience 95°F temps this summer and all of our engines derated, but it was not as dramatic as we anticipated. We only ended up derating to roughly to 8.0-8.7 mW from our normal output of 9.6mW. We found that manually running the radiator fans to 100% helped stave off derating. We are also in the process of installing a soft water spray mist system on our radiators, in an effort to increase their cooling efficiency. We have found that a cooling mist system can lower radiator output cooling water by as much as 10°F. When our cooling mist system is running our engines do not derate.
I should also add that our facility is located in Rochester, MN. During construction I asked our design engineer several times about a cooling system recirc pump. Each time they addressed the topic with, “you won’t need it”. I would have to think, though, that if you had a recirc pump in your cooling water system, that you would be able to reduce the glycol % due to the constant motion of the fluid. We have talked about moving this direction in the future, if we run into high levels of engine derate due to high ambient temps.
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This topic was modified 5 years, 5 months ago by
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