Potassium hydroxide is a kind of strong alkali, which is often used as chemical raw materials. However, if the main content of the main product fails to meet the requirements when it is used, the subsequent use effect will also be affected. How to solve the problem when the main content of the product is low? Let's take a look.
The main content refers to the mass fraction of KOH in the finished product, which is one of the main parameters to determine the product quality. Generally, the content is required to be greater than 90%. In this process, the key is to control the temperature of lye. 1.148% alkali liquor concentration shall reach or be greater than 48% when it is evaporated through the primary and secondary effect evaporators, so as to prepare for the qualification of the following processes. This process mainly uses the heat generated by steam condensation to evaporate the water in the lye so as to increase the concentration. Therefore, it is necessary to ensure that the steam pressure and temperature meet the corresponding requirements:
The boiling point of alkali liquor can be reduced under vacuum, so in order to save energy and improve efficiency, the vacuum degree in the evaporator should be kept as high as possible. The vacuum degree of alkali liquor in the two effect evaporator is 0.085~0.094MPa, and the temperature is 75~85 ℃. The effect is good.
1. Increase the pressure and temperature of high-pressure steam
The rising film evaporator uses high pressure steam as the heating medium, which can continue to increase the concentration of alkali liquor. The temperature of potassium hydroxide alkali liquor is generally between 190~210 ℃.
2. Hydrogen combustion furnace and molten salt system
Molten salt HTS is used as the heating medium in the process of concentration and production, while hydrogen combustion furnace is used to provide heat source for BTS heating. The heat provided by the combustion furnace must be stable, so as to ensure the stability of the molten salt temperature and flow, generate enough stable heat to heat the alkali liquor, and make the alkali liquor temperature after passing the concentrator meet the standard requirements, generally between 380-400 ℃.
3. Keep the system closed
In order to avoid the temperature reduction and deliquescence of the alkali liquor and reduce the K0H content in it, the alkali liquor shall be kept as closed as possible during the flow from the concentrator to the flaker to avoid contact with the air.
The four solutions described above are to solve the problem of low main content of potassium hydroxide, which can effectively improve the purity of the product. More relevant content will come to our website http://www.jinhao360.com Ask and understand!