Why do the saltwater pipes in the post-reaction tank get clogged?
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This post was last edited by sunjl1981 on 2013-1-6 at 23:03. The saltwater system has two rear reaction tanks; Tank A is equipped with a stirrer and NaCO3 solution is added to it. The saltwater flows from Tank A to Tank B via overflow, with Tank B being used to extend the reaction time. The intermediate overflow pipe is made of CS-lined PO material, with a DN350 size. Currently, brine from tank A often overflows, indicating that the overflow pipe between the two tanks is blocked; no action has been taken yet. Let’s discuss how pipes of such a large diameter can get clogged # hcbbs
There’s too much calcium carbonate at the bottom of channel A; it needs to be dealt with. Or maybe the flow rate is too high – that’s what it seems to be
Possible reasons include: 1. There are crystals at the top of slot A; they have not settled properly, so stirring is used to remove them first. 2. The surface of the overflow tube is not smooth and becomes wetted by saltwater, which facilitates the adhesion of crystals; trying covering the surface with plastic sheeting could be an option. 3. Is the temperature in the overflow tank too low?
Do you think it’s possible that the issue is caused by the prolonged accumulation of impurities such as saltwater and calcium carbonate when the flow rate is unstable or low? Once calcium carbonate forms deposits on the pipe walls, it’s difficult to remove them, and with the help of a small amount of magnesium hydroxide, more and more deposits accumulate We will start disassembling it tomorrow; I will keep you updated on the specifics!
There may be several reasons: 1. Large fluctuations in flow rate or an upward angle of the overflow pipe; 2. Excessively high calcium carbonate content, high saltwater concentration, or low saltwater temperature; 3. The size of the rear reaction tank A is too small – it is best for the saltwater to stay in the front reaction tank for 40 minutes – as well as excessive stirring intensity
This overflow pipe gets clogged easily; it is recommended to install a compressed air pipe on it, with several flushes per shift
After processing, it was found that there was a small amount of sediment on the overflow tube, and the area around the connection between tank B and the overflow tube was covered with sediment. The sediment was slightly yellow and white in color, and not very hard. In my opinion, the poor quality of the raw salt – with excessive magnesium levels, many solid impurities, and a high amount of organic matter – results in inadequate performance of the pretreatment unit. The brine exiting this unit is cloudy; over time, large amounts of flocculent substances fail to be removed from the pretreatment unit and end up in the subsequent reaction tanks, where they accumulate at the pipe openings. Due to the low pressure in the overflow pipes, these deposits can cause blockages over time, thereby affecting production! Let’s discuss it together!
This post was last edited by pzhhuagong on 2009-8-21 at 11:41. I don’t think the issues mentioned above are the main problems; a high level of impurities is actually a characteristic of this subsequent reaction stage. The following points need to be confirmed: 1) If tank A is equipped with agitation, does tank B also have agitation? It’s better if both tanks have agitation, so as to prevent calcium carbonate from depositing there! If the agitation in tanks A and B is proper, there won’t be overflow in tank A. 2) Where exactly is sodium carbonate added to tank A? If brine enters tank A from its bottom, then the sodium carbonate addition pipe should be inserted near the brine inlet at the bottom of tank A, so that the reaction can take place promptly and the reactants won’t aggregate due to agitation. 3) Is the pipe from the outlet of tank B to the intermediate tank unobstructed? Some pipes leading to the top of the intermediate tank have large U-shaped bends, which may cause overflow in either tank A or tank B. 4) What about the sludge removal operation in the preprocessor? This issue is easily overlooked; when sludge is removed, the brine outlet of the preprocessor is closed, causing the brine level to rise. After sludge removal is complete, the outlet should be opened slowly to prevent a large amount of brine from flowing from the preprocessor into intermediate tank A, which could result in temporary overflow in tank A.
I analyzed that the main reason is the too small difference in liquid level between the rear reaction tank and the front reaction tank, which results in the pipe between them being constantly filled with saline. The particles resulting from the reaction accumulate there. The solution is to lower the liquid level in the rear reaction tank, thereby increasing the liquid level difference between the pipe and the rear reaction tank
This brine purification process should use the Kai membrane technology. I believe that the flow rate of the brine is too high, resulting in a short residence time of the brine in tank A; this leads to incomplete reactions. The particles resulting from these reactions settle within the connecting pipes between tanks A and B, and over time these pipes get blocked. We have already cleared them out.
I agree with the opinion from the 8th floor. In my view, the high level of impurities in the raw salt also plays a significant role; as a result, these impurities tend to accumulate in the pipe that carries the substance from tank A to tank B (provided that the reaction in tank A is incomplete and the reaction time is too short). Also, the location where NaCO3 is added is very important!