Drying of pesticides mainly includes two parts. One part is the drying of pesticide processing aids and fillers, and the other is drying in the preparation process to get the final product. Because the moisture content of pesticide products is more stringent, the moisture contained in the filler directly affects the quality of the product, so the drying of the filler is also an important part of pesticide powder processing. Due to the large amount of pesticides, considering the product prices, the fillers of pesticide powders are mainly clay, clay, kaolin, white carbon and other minerals. For this reason, the drying equipment for pesticides basically uses convection drying, and is mainly based on drum dryers, box dryers, air dryers, and shaft kiln. With the improvement of formulation technology, spray dryers and other equipment have also begun to be equipped with pesticides. Rotary flash dryers and paddle dryers are also used in succession. 3 Drying Equipment for Pesticide Production 3.1 Box Dryer Box Dryer is one of the most used drying equipments in pesticide plants. The box dryer has the advantages of simple equipment manufacturing, low investment, easy operation, convenient replacement of varieties, and low exhaust gas treatment. Applicable to small batches, frequently changing varieties, batch production occasions. However, it is static intermittent drying. The traditional equipment has poor working conditions, labor intensity is also large, and the production cycle is long. Although the operating temperature is not high, because the material is subjected to the same temperature for a long time, it is easy to cause the dried material to overheat and deteriorate. After the general product is dried, it must be crushed and it is not suitable for the production of large-tonnage products. Box dryers also have two types of co-current and flow-through. The former is mainly used for the drying of paste-like materials, and the flow-type box dryer is mainly dried by hot air through the surface of the wet material. When the hot air passes through the surface of the wet material, the surface material is heated and the moisture vaporizes first. Due to the difference in humidity generated inside and outside the material, the internal moisture migrates outward and vaporizes, and the above process is continuously repeated so that the material is finally dried. Through-flow box dryers are hot air that passes vertically through the material and are used primarily for the drying of bulk and granular materials. Compared with co-flow box dryers, the drying time is shorter and the production efficiency is higher. Most pesticide plants use trays placed on steam tubes to manually turn animal feeds and dry them under static conditions. This method is inevitably labor-intensive, and more importantly, the unevenness of the material drying is unavoidable, the product quality cannot be guaranteed, and the energy loss is also very large. The thermal efficiency of the box-type dryer is not more than 20%. In recent years, drying equipment companies have made technological improvements to box dryers and have made improvements in the following areas. First, the trays of the box dryers are cart-type, placing multi-layer trays on carts, improving work efficiency and reducing labor intensity. Secondly, some forced hot air circulation methods are used to make the temperature in each corner of the dryer basically the same, which not only ensures the uniformity of product moisture and quality, but also greatly improves work efficiency and thermal efficiency. Although the box dryer is the most primitive and oldest drying equipment, it is also the most practical and non-removable. It has the advantages that other drying equipment cannot match. Therefore, although many new types of drying equipment have been developed, there are still no signs of withdrawal. The automatic temperature control system and ventilation system of the box dryer should be further developed. A gas relative humidity measuring instrument is installed at the gas outlet and some hot air circulation is adopted to correct its shortcomings as far as possible, so that this ancient equipment can play a new role. Pvc Compounding Line,Four Flights Co-Kneader,Pvc Co-Kneader Line,Compounding Extruder JIANGSU XINDA TECH LIMITED , https://www.xindaextruder.com
In recent years, China’s pesticide production ranks second in the world. In 1999, the pesticide production (based on 100% active ingredient) was 423,500 tons. According to incomplete statistics, the annual cost of pesticides consumed in China is as high as 20 billion yuan. At present, there are more than 1600 pesticide manufacturers, including more than 500 original pharmaceutical factories, more than 1,000 pesticide processing and packaging plants, and China has become a large producer of pesticides. Pesticides are a class of products with strong international competitiveness in China. In recent years, the international trade index has been around 0.27, and the sales of pesticides have also ranked among the top ten in the world. Sales revenue accounts for 8% of the total sales of the world's pesticide market, and is a net exporter. Currently, the export volume accounts for more than 25% of the total.
Application of drying equipment in agriculture
The processing of many pesticides is inseparable from the drying equipment. The high demand for pesticide formulations has also brought new development space for drying equipment. In the past, the drying equipment in the pesticide industry was dominated by static drying in ovens, drying rooms, etc., and was powdered after drying. Not only the production conditions are very harsh, but the use of medicines and the exertion of their efficacy are all subject to certain restrictions. The use of new drying methods and new drying techniques will play a very important role in the development of new pesticide formulations. 2 Characteristics of Pesticide Drying There are many differences between the drying of pesticide drying equipment and other chemical products. First, there are many formulations of pesticides. In addition to liquid formulations, solid dosage forms have powder, granules, lumps, strips, and flakes. For pesticides, drying does not merely evaporate water, but forms different solid forms during the drying process, but also ensures the action of the drug, so the drying process is also the manufacturing process of the dosage form. Therefore, the drying equipment used is more complicated. Second, toxic and odorous are the basic characteristics of pesticide products, and the protection of dry site workers is very important. Third, gas emissions during drying operations must also be strictly controlled. Such as the drying of highly efficient herbicides, the safety of crops should be ensured if there are farmland around the production site. Finally, as far as possible, economical heat sources are used for drying. In particular, pesticides with low added value are required to control production costs.