Regarding circulating water treatment issues
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Dear friends from HaiChuan, our company is located in Lianyungang, northern Jiangsu. The water used for circulation is groundwater, which has a high salt content as well as high levels of calcium and magnesium ions. This poses many problems for boilers and the circulation systems. At present, the equipment and pipes used for water circulation are severely scaled up. If there are professionals experienced in water treatment, please feel free to contact me at zhangjialei75828@163.com. You are welcome to visit our company for an on-site inspection. Thank you!
For water with high salt content, first, the concentration factor should not be set too high; secondly, attention must be paid to the selection of slow-release scale inhibitors. Another thing is to control the system’s pH level; generally, acid needs to be added to prevent the pH from becoming too high. I don’t know the specific details, nor do I know where the problem lies.
Should the circulating water be treated first?
The hardness is too high; it’s necessary to carry out pre-treatment first to reduce the hardness of the raw water! Last edited by li*ch1968 on 2009-4-6 at 10:08.]
First, add lime, soda ash, etc. to remove hardness; second, add a slow-release scale inhibitor to the circulating water and maintain a low concentration ratio!
Regarding this issue, I believe it is necessary to address both the symptoms and the root causes; groundwater must be pre-treated before it can be used, otherwise the addition of scale and corrosion inhibitors will not have a significant effect! Using soda lime to reduce hardness, ion exchange resins to lower salt content, and membrane treatment processes to purify the feed water – these measures will definitely lead to improved results!
Your situation is very similar to that in Shandong – both areas use groundwater with extremely high hardness. There are usually only a few solutions for such situations; either install a water softening device, which is typically a sodium ion exchange bed ； Either increase the drainage volume to reduce the concentration ratio ； Also, use the excess demineralized water supplied to the boiler as make-up water for the circulating water. This post was last edited by li*ch1968 on 2009-4-6 15:30]
I think if possible, we should add a water treatment plant to treat the water first, then apply a pre-coating to the equipment and pipelines, add scale inhibitors, and install bypass filters to see how it works
High calcium hardness in groundwater is relatively common, especially in the north. There are several options for controlling the use of such water: 1. Soften the raw water first – this is the best approach, as it is optimal for equipment and circulation systems; however, it comes with the highest treatment costs and is not the most suitable option； 2. Control the alkalinity of the circulating water by installing an acid addition system; as long as the alkalinity is maintained around 200, even if the total hardness is between 1200 and 1500, there is no major issue using scale inhibitors. This approach is the most feasible ； 3. Use scale inhibitors; relying solely on scale inhibitors to prevent scaling is not practical – firstly, the cost is high, and secondly, it is difficult to control scaling, so this approach is not suitable.
Water used in boilers must be softened; as for circulating water, it doesn’t need to be softened, but there is a limit to the concentration ratio
Pre-treatment is recommended; softened water is sufficient for circulating water, while demineralized water should be used for boiler water
In addition to treating the circulating water, it is advisable not to use all of this circulating water; some fresh water can be added. Otherwise, no matter how advanced the treatment processes are, some accumulation will inevitably occur, and problems will eventually arise.
Add a reverse osmosis treatment to the water used for replenishing the circulating water; otherwise, the quality of the circulating water will continue to deteriorate. If desalinated water is available, it can be used to replenish the circulating water, and considering reducing the frequency of water replenishment
Sealing treatment is carried out by adding chemicals; there are many companies and research institutions in China that offer water treatment technologies.
For 4# yplhq water with high salt content, first, the concentration factor should not be set too high; secondly, attention must be paid to the selection of slow-release scale inhibitors. Another thing is to control the system’s pH level; generally, acid needs to be added to prevent the pH from becoming too high.