Posted in India forum
Let’s look at what happens to the water after it has performed its function of removing the heat from the oil and is itself now warm. In the olden days it was simply flushed and fresh water was used. With growing environmental concerns coupled with the scarcity and cost of fresh water it needs to be recirculated. In order for it to be effectively re-used as a cooling media, the water needs to lose the heat that it has picked up and be cool enough to be able to remove heat from the oil.
For this the warm water is then pumped to a cooling tower where an air draft is used to cool it. There are two processes involved here. The cooling of oil using water, which in turn gets heated & the cooling of hot water with ambient air. We know that no process is 100% efficient. Assuming we have a well-designed processes, each would have an overall efficiency of say 80%, in which case we have 20% loss of efficiency in each process.
