Questions about circulating water

It should be determined based on the process requirements and energy balance. The process requirements determine what water you use, while the balance determines the amount. It seems to have little to do with the amount of other water.

Is there a clear relationship between the amount of circulating water and the amount of cooling water, demineralized water, and well water? Circulating water is generally used for cooling. Naturally, the amount must be calculated through energy balance. It shouldn't have much to do with other things, right? Unless you use other water instead? The host didn’t seem to explain it.

Sorry, I can't explain it clearly. Because I was doing research on a melamine project, one designer said that the circulating water volume was 3000t/h and the supplementary water was 80t/h, but the cooling water volume was not mentioned. ； Another designer only mentioned that the cooling water volume is 532t/h, but not the circulating water volume (as mentioned above). Because it is difficult to compare, I would like to ask everyone for advice.

What is the annual output? 6,000 or 12,000?

I don’t know much about the melamine project. However, the data discrepancy between the two design institutes is large enough, and one of them must have problems. The poster can compare the processes of both parties and look at the water balance diagram and energy balance diagram. Generally, demineralized water has nothing to do with cooling circulating water. Well water can be used as supplementary water for cooling circulating water. The specific relationship between the two should comprehensively consider the environment (temperature/humidity) of the project construction location. Generally, during the feasibility study, it can be roughly estimated that the supplementary water volume is 5% of the circulating volume (in fact, it is generally less than 3%).

Brother, if there is consumption of desalted water, cooling water, etc., I can calculate the consumption of fresh water or primary water. However, the amount of circulating water is not directly related to the data you provided. If the cooling water includes circulating water, desalted water, and well water, it can be calculated. Just make a subtraction. Please introduce the usage of these types of water. It will be helpful to help you calculate.

Your circulating water should refer to cooling water in the ordinary sense, that is, water circulated through the cooling water tower. Obviously, your process also uses well water and brine as cooling media. There is no necessary connection between the three. It is just that the application occasions are different and should be calculated independently. According to what you said, the circulation volume is 3000t/h, then the volume out of the cooling water tower should be 3000t/h. Since the cooling water tower is generally open now, some water will be lost, plus other possible losses, so a certain amount of water needs to be added to ensure a constant amount of cooling water in the system. This is what you call 80t/h of supplementary water. Many types of water are used in production, so do not mix them together. As a process engineer, you should not mix them together when calculating them. You should calculate them separately according to their different characteristics, so that you can get correct results.

Prepare to do a 30,000t/a triamine project. Brother Blue Point, the data they provided is as mentioned above: Cooling water volume - 532t/h, well water volume - 90t/h, desalted water volume - 10t/h. Can you help me calculate the amount of fresh water?

The calculation of cooling water supplementary water is related to these factors: Supplementary water quality, temperature difference, meteorological conditions, and circulating water concentration ratio. Under normal circumstances, new chemical projects require a concentration ratio of more than 2. In the south, the supplementary water volume is about 2.5% of the circulating water (i.e., cooling water). In the northwest, the supplementary water volume must be about 3%, for reference.