What should the concentration multiplier be set at?
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For a single water treatment: alkalinity of 360 mg/l, hardness of 30 mg/l, and chlorides of 41 mg/l – what is an appropriate concentration multiplier for such water?
This should be soft water; keeping it around 2.5 should work
It’s not just about looking at the parameters of the raw water; you also need to consider your evaporation rate.
Low hardness and high alkalinity; no problem occurs even if it is concentrated 3.5–4 times without acid adjustment. If acid adjustment is used, it’s fine to increase it to 6-7 times as much.
It is possible to keep it between 4.5 and 5, or even above 6.
What determines the control concentration ratio? Is the role of adding acid or base to adjust the pH value? Why can the acid concentration multiplication factor be higher
Keeping it at **5 times the standard is no problem.
Reply to 6# smilezcx: In the current recirculating water system, the control of calcium carbonate is based on the total alkalinity associated with calcium hardness; it is required that the sum of calcium and total alkalinity be less than 1100. Of course, if the alkalinity or calcium hardness is very low (such as in the water quality mentioned on the first floor), the limits can be relaxed somewhat. If we reduce the alkalinity or calcium hardness of the make-up water, we can increase the concentration ratio of the circulating water. For this reason, we can use certain methods to indirectly increase the concentration factor. For example, 1: By adding acid, carbonate or bicarbonate is converted into water and carbon dioxide, thereby reducing alkalinity. 2. Reduce calcium ions in the make-up water by adding lime.
The purpose of increasing the concentration ratio is to save water resources and enable its reuse. However, a higher concentration ratio is not necessarily better. Apart from the quality of the water used for replenishment, it also depends on scale and corrosion inhibitors, as well as whether other auxiliary facilities are in use. If the cost associated with increasing the concentration ratio exceeds the cost of adding more water, then it holds little significance. While there are environmental benefits, if there are no economic advantages, then measures to increase the concentration ratio will not be pursued. Therefore, the concentration factor should be determined in consideration of actual operating conditions, so as to achieve both water savings and reduced operating costs.