In a falling film evaporator, it is important to control the product extraction degree, which usually depends on the following methods to achieve:
1. Adjusting the total feed flow rate: manipulating the feed liquid platform flow rate can indirectly control the product extraction degree. By monitoring the total flow rate of the feed and adjusting accordingly, a certain concentration value of the product can be achieved.
2. Adjusting the heating temperature and operating temperature of the air conditioning evaporator: By adjusting the heating temperature and pressure in the air conditioning evaporator, the evaporation rate can be controlled, which in turn affects the extraction degree of the product. Generally speaking, increasing the heating temperature or reducing the operating temperature can increase the evaporation rate, thereby increasing the extraction degree of the product.
3. Detect the concentration value of the product and provide feedback adjustment: Use online concentration sensors or other measuring instruments to monitor the content of the product, and adjust the main parameters such as air conditioning evaporator heating temperature, feed flow rate, etc. through feedback control system to maintain the required concentration value of the product.
4. Selecting multi-level evaporation: For products that require very high concentrations, multi-level evaporation devices can be used to gradually increase the concentration value of the product through repeated evaporation. The actual operating parameters of each evaporator can be controlled according to the actual situation.
5. Selection of recycling equipment: For specific uses, recycling equipment can be designed to recycle by-products or organic solvents to achieve the desired product concentration value.
This method can be used alone or in combination to achieve concentration control of the product. In the actual control process, it is necessary to continuously detect the concentration value of the product, adjust the main operating parameters according to production needs, and maintain the concentration value of the product within the expected range.