Alkali storage tank
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Is it better to use rectangular or cylindrical tanks for storing alkaline solutions? What material is good? Do 40% of the alkali solution storage tanks need insulation? Do 15% alkali solution storage tanks need insulation? Is 40% concentrated caustic soda in the factory usually prepared in-house or purchased externally? Please ask those who are aware to help answer. Thank you! This post was last edited by nanjingdaxue on 2009-3-3 15:21]
Is it better to use rectangular or cylindrical tanks for storing alkaline solutions? Answer: What material is good for a cylindrical shape? Answer: Do storage tanks lined with PTFE or PFA containing 40% alkaline solution need insulation? Do 15% alkali solution storage tanks need insulation? Answer: Insulation is applied in all cases; if conditions permit, heat tracing is the best option. Is 40% concentrated caustic soda in the factory usually prepared in-house or purchased externally? Answer: Under normal circumstances, one needs to purchase the alkali tablets by themselves and then prepare them. If there is anything you don’t understand, feel free to ask further questions. This post was last edited by www557 on 2009-2-28 21:36]
In our factory, the alkali storage tanks are all cylindrical in shape; carbon steel is usually sufficient as the material. Insulation is required for all of them, and it’s advisable to install heating elements when winter temperatures drop below -15 degrees Celsius. 40% concentrated caustic soda used in the factory is generally purchased externally
15% alkaline solution is also used as a cooling medium, at a temperature of around 25-35 degrees. Is it acceptable not to use any insulation in this case? If it’s insulated, won’t cooling render it ineffective?
Is it better to use rectangular or cylindrical tanks for storing alkaline solutions? Answer: We use cylindrical ones for singing; what material is good? Answer: Do storage tanks lined with PTFE or PFA containing 40% alkaline solution need insulation? Do 15% alkali solution storage tanks need insulation? Answer: Insulation is applied in all cases; if conditions permit, heat tracing is the best option. We use cement to cover most of it, leaving only the tank opening exposed; in winter, steam tracing pipes are needed, and we have installed steam traps at those pipes – the result has been good. This is for reference only: is the 40% concentrated alkali used in the factory prepared locally or purchased externally? Answer: Under normal circumstances, one needs to purchase the alkali tablets by themselves and then prepare them. Our factory purchases these from outside; if you have any questions, feel free to ask. Some of the content is quoted from the moderator; please don’t be upset.
Is it better to use rectangular or cylindrical tanks for storing alkaline solutions? Rectangles and circles are both acceptable; circles are more common. What material is good? If the temperature is below 45 degrees, carbon steel is sufficient. Do 40% of the alkali solution storage tanks need insulation? Do 15% alkali solution storage tanks need insulation? Insulation is necessary, as the alkali tends to crystallize; therefore, heat tracing pipes (with hot water) should also be installed. It is best to maintain the temperature of the alkaline solution between 20 and 40 degrees. High temperatures cause corrosion in carbon steel. Is 40% concentrated caustic soda in the factory usually prepared in-house or purchased externally? Alkali solutions with a concentration of 30% are easily available for purchase, while those with a 40% concentration are less common; it is recommended to have the solid alkali purchased by the factory for preparation.
In the end, Q235A was chosen as the base material for the equipment. Could someone please advise whether heat treatment is required during processing? What are the specific requirements?
Alkali storage tanks in factories are generally circular in shape; square tanks have less structural strength than circular ones. However, if the tank’s volume is small, a square shape can also be used, which helps to reduce costs. 15% alkali solution does not require insulation; its freezing point is not high, so insulation is not needed. 40% alkaline solution can possibly be purchased externally, but this is a high-concentration alkali; the usual concentration of alkaline solutions is only 30-32%. If no high-concentration alkali is available in the vicinity, it will naturally have to be prepared locally. One can purchase solid alkali at a higher price and dilute it with water to obtain a 40% alkaline solution, or combine 30% alkaline solution with solid alkali in the right proportions to create a 40% alkaline solution.
Generally, the condensation temperature of 14% liquid caustic is minus 17 degrees, while that of 18% liquid caustic is minus 25 degrees; therefore, it is determined based on the local climate whether 15% liquid caustic requires insulation. Furthermore, liquid alkalis generally cannot be heated. If heating is applied, it can easily lead to the precipitation of solid alkalis, which over time may cause pipe blockages. Our company’s lye line is not equipped with heating. 25% liquid caustic can be transported in winter without condensation.
It was only after reading the replies that I understood why the alkali tank of the device I saw last time was made of carbon steel and didn’t have any heating system – it turns out temperature needs to be taken into consideration