Development status and characteristics of high-efficiency mixing granulator for calcium carbonate industry

  The general requirements of the granulator used in the calcium carbonate industry are high thermal efficiency, low energy consumption, simple configuration, convenient control, small footprint, and safe and hygienic operating environment. At present, the most commonly used high-efficiency mixing granulators in the inorganic salt industry include: rotary tube dryer, rotary indirect heating dryer, disc continuous dryer, air dryer (subdivided into pulsed air flow, air rotation, positive and negative pressure two -Level airflow drying), rotary flash dryer, rotary drum dryer, spray dryer (also divided into granulation, powder, centrifugal, pressure), 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 a guarantee for product quality, but they all have the problem of exhaust gas collection "dust". Due to the continuous increase of nano-level products, the original particle size is getting smaller and smaller, the potential water content of the paste material is increasing, and the company is constantly developing in the direction of large-scale and large-scale. Especially for some large-tonnage products, such as precipitated calcium carbonate, the current national production volume is more than 3 million tons. The annual output of the production line is 10,000 tons. The scale of 100,000 tons requires five sets of high-efficiency mixing granulators. A company in Guangxi plans to get 500,000. Tons, according to the current high-efficiency mixing granulator level, no matter the area of the equipment or the amount of "dust" collected from the exhaust after the product is dried, it is very large.

  According to the pulse bag filter commonly used in the industry, the operating environment is very harsh, 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 collecting "dust" in exhaust gas after the objects are dried. Taking the calcium carbonate industry as an example, more than 200 enterprises across the country basically use rotary indirect heating dryers, disc continuous dryers, rotary tube dryers, etc. in the selection of high-efficiency mixing granulators. Although the production efficiency is satisfied , Energy consumption and exhaust "dust" are not ideal. When entering a calcium carbonate enterprise, a layer of white calcium carbonate powder is covered from the ground to the roof, and even the desks and chairs in the office are covered with white. There are management problems, and more importantly, the exhaust gas does not collect "dust" after drying. Recently, the industry introduced dust removal equipment produced by DuPont, which basically solved the problem.
Therefore, the combined high-efficiency mixing granulator should include: providing heat source equipment, primary and secondary high-efficiency mixing granulators, exhaust gas collection "dust" equipment, etc. It is hoped that equipment manufacturers and research units will have high thermal efficiency, low energy consumption, simple configuration, Make a fuss about the convenience of control, make fuss about the combination of high-efficiency mixing granulators, serve others, and develop yourself. If the drying problem of the calcium carbonate industry is solved, and the equipment is highly efficient and environmentally friendly, the drying problems of other varieties will be solved.