The overall requirements of pelletizers used in calcium carbonate industry are high thermal efficiency, low energy consumption, simple configuration, convenient control, small floor area, and safe and sanitary operating environment. At present, the efficient mixing granulators commonly used in the inorganic salt industry are: rotary tubular dryer, rotary indirect heating dryer, disc continuous dryer, airflow dryer (also divided into pulse airflow, airflow rotation, positive and negative pressure two-stage airflow drying), rotary flash dryer, rotary drum dryer, spray dryer (also divided into granulation, powder, centrifugal, pressure type), vibrating fluidized bed dryer, static vacuum dryer Hot air circulation oven, rake type, paddle type vacuum dryer, boiling dryer (horizontal, vertical), etc.

　　These high-efficiency mixing granulators provide guarantee for product quality, but there are problems of tail gas "dust" collection. Due to the continuous increase of nanoscale products, the original particle size is becoming finer and finer, and the potential water content of paste materials is increased. In addition, the enterprise is constantly developing towards large-scale and large-scale, and the enterprise is eager to combine efficient mixing granulator. Especially for some large-tonnage products, such as precipitated calcium carbonate, the current national production capacity is more than 3 million tons, the annual production capacity of small production lines is 10000 tons, and the scale of 100000 tons requires five sets of high-efficiency mixing granulators. An enterprise in Guangxi plans to obtain 500000 tons. According to the current level of high-efficiency mixing granulators, the floor area of the equipment or the amount of "dust" collected from the dried tail gas of the products are large.

　　According to the pulse bag-type dust remover commonly used in the industry at present, the operating environment is very bad, and effective measures must be taken to solve it. Therefore, we hope that the equipment development unit will focus on solving two problems, one is the drying of paste-like fine objects with high water content, and the other is the industrial hygiene problem of "dust" collection after the objects are dried. Taking the calcium carbonate industry as an example, more than 200 enterprises in the country basically adopt rotary indirect heating dryer, disc continuous dryer, rotary tube dryer, etc. in the selection of high-efficiency mixing granulator. Although the production efficiency is met, the energy consumption and tail gas "dust" collection are not ideal. Once entering the calcium carbonate enterprises, from the ground to the roof, there is a layer of white calcium carbonate powder, even on the desks and chairs in the office, In this respect, there are management problems, and more importantly, the "dust" collection of tail gas after drying is not qualified. Later, the industry introduced dust removal equipment produced by American companies, which basically solved the problem.

　　Therefore, the combined high-efficiency mixing granulator should include: providing heat source equipment, primary and secondary high-efficiency mixing granulator, tail gas "dust" collection equipment, etc. I hope that the equipment manufacturing and research units will make contributions in terms of high thermal efficiency, low energy consumption, simple configuration, convenient control, etc., and in terms of combining high-efficiency mixing granulator, serving others and developing themselves. If the drying problem of calcium carbonate industry is solved, and the equipment is efficient and environmentally friendly, the drying problem of other varieties will be solved.