Polyvinyl alcohol (PVA) is an important chemical raw material, which is widely used in fibers, coatings, adhesives and other fields. Drying is a key link in its production process. However, there are some problems with the current drying status of polyvinyl alcohol, which affects the production efficiency and product quality.
First of all, the traditional polyvinyl alcohol drying process mainly uses a rake dryer. This type of dryer is bulky and has low heat transfer efficiency. Its large volume not only takes up a lot of production space, but also its heat transfer efficiency is low, resulting in a long drying process that affects production efficiency. In addition, the dryer has a thicker inner wall, which further reduces the heat transfer coefficient, resulting in a worse heat transfer effect. Especially after the inner wall is sticky, the heat transfer efficiency will be further reduced, resulting in unsatisfactory drying results.
Secondly, the rake dryer has the problem of dry dead corners and serious sticking walls. Inside the dryer, the rake cannot be scraped at the temperature measurement point, bearing seat and end plate, forming a drying dead angle. The materials in these dead spots cannot be effectively dried, resulting in a decrease in product quality. In addition, due to the long barrel of the equipment, the concentricity of the cylinder is difficult to guarantee, so that the gap between the rake and the cylinder wall is uneven. This will cause some materials to be unable to be scraped up, and will scar and bond on the wall after long-term operation, affecting the heat transfer effect and product quality. Usually after a period of operation, it is necessary to clean the internal leather, which not only increases the difficulty and workload of the operation, but also affects the continuity of production.
Finally, rake dryers are difficult to clean and have a high failure rate. Structures such as rakes and bearing housings inside the dryer make it difficult to clean up inside. Each clean-up requires a long shutdown, which not only affects the continuity of production, but also increases the material consumption and the generation of non-conforming products during the shutdown. In addition, parts such as the dryer's rake connections and bearings are prone to damage, resulting in frequent start-ups, shutdowns, and repairs. This not only increases production costs and maintenance costs, but also brings difficulty and trouble to process operations.
In view of the above problems, some improvement measures can be taken to improve the drying effect and production efficiency of polyvinyl alcohol. For example, optimize the structural design of the dryer to reduce the volume and improve the heat transfer efficiency; Improve the design and arrangement of the rake to reduce the dry dead angle and sticking to the wall; Advanced automatic control system and intelligent monitoring technology are used to realize precise control and fault warning of the drying process. These measures will help to improve the technical level and competitiveness of the polyvinyl alcohol drying process.