Limestone Raymond mill plays an important role in preparing desulfurized limestone powder. The quality of Raymond limestone mill directly affects the quality, fineness and particle size distribution of limestone powder. The following will describe the technical characteristics and specific application of Raymond limestone grinding mill in desulfurization limestone pulverization.
I.Application significance of Raymond limestone mill in desulfurized limestone pulverization
At present, more than 90% of thermal power plants in China adopt limestone gypsum desulfurization technology, which has mature technology and low cost. Both processes need limestone powder to absorb sulfur dioxide, and the smaller the particle size of limestone powder is, the more conducive to the absorption of SO2.
II.Main factors affecting desulfurization efficiency of limestone
（1）Quality of limestone
Generally, the content of CaSO4 in limestone shall be higher than 85%. If the content is too low, it will bring some problems to the operation due to more impurities. The quality of limestone is determined by the content of Cao. The higher the purity of limestone, the better the desulfurization efficiency. But limestone is not necessarily CaO content, the higher the better. For example, limestone with Cao > 54% is Dali Petrochemical due to its high purity, not easy to grind and strong chemical stability, so it is not suitable to be used as desulfurizer.
（2）Limestone particle size (fineness)
The particle size of limestone directly affects the reaction rate. When the specific surface area is larger, the reaction speed is faster and the reaction is more sufficient. Therefore, it is usually required that the passing rate of limestone powder through 250 mesh sieve or 325 mesh sieve can reach 90%.
（3）Effect of limestone reactivity on desulfurization system performance
The limestone with higher activity can achieve higher sulfur dioxide removal efficiency under the condition of maintaining the same limestone utilization rate. Limestone has high reaction activity, high limestone utilization rate and low content of excess CaCO in gypsum, that is, gypsum has high purity.
III.Working principle of limestone Raymond mill
Raymond limestone mill is composed of grinding host, grading screening, product collection and other components. The main engine adopts the integral casting base structure, and the damping foundation can be adopted. The classification system adopts the structure of mandatory turbine classifier, and the collection system adopts pulse collection.
（1）Working principle of Raymond limestone mill
The materials are crushed into qualified particle size by jaw crusher, lifted to the storage hopper by dustpan elevator, and then quantitatively sent to the main machine cavity by feeder for grinding. The main engine cavity is supported on the plum blossom frame, and the grinding roller device rotates around the central axis. The grinding roller swings horizontally outward under the action of centrifugal force, so that the grinding roller presses the grinding ring, and the grinding roller rotates around the grinding roller shaft at the same time. The material lifted by the rotating blade is thrown between the grinding roller and the grinding ring to achieve the function of crushing and grinding due to the roller grinding of the grinding roller.
（2）Working process of Raymond limestone mill and separator
The ground powder is blown by the air flow of the blower to the classifier above the main machine for screening, and the fine and coarse powder still falls into the main machine for regrinding. If the fineness meets the specification, it flows into the cyclone collector with the wind and is discharged through the powder outlet pipe after collection, which is the finished product (the particle size of the finished product can be as high as 0.008mm). The purified air flow flows into the blower through the pipe at the upper end of the cyclone, and the air path is circulating. Except for the positive pressure from the blower to the grinding chamber, the air flow in other pipelines flows under negative pressure, and the indoor sanitary conditions are good.
IV.Technical characteristics of Raymond limestone mill
Limestone Raymond mill produced by HCMilling (Guilin Hongcheng) is a technical update based on R-type grinding mill. The technical indexes of the product have been greatly improved compared with the R-type machine. It is a new type of grinding mill with high efficiency and energy saving. The fineness of finished products can be 22-180 μ M (80-600 mesh).
（1）(New Technology) plum blossom frame and vertical swing grinding roller device, with advanced and reasonable structure. The machine has very low vibration, low noise, stable operation and reliable performance.
（2）The processing capacity of materials in unit grinding time is larger and the efficiency is higher. The output increased by more than 40% year-on-year, and the unit power consumption cost was saved by more than 30%.
（3）The residual air outlet of the pulverizer is equipped with a pulse dust collector, and its dust collection efficiency reaches 99.9%.
（4）It adopts a new sealing structure design, and the roller grinding device can fill grease once every 300-500 hours.
（5）It adopts the unique wear-resistant high chromium alloy material technology, which is more suitable for the collision and rolling conditions with high frequency and large load, and its service life is nearly three times that of the industry standard.
Compared with the traditional Raymond mill, suspension roller mill, ball mill and other processes, the limestone Raymond mill can reduce energy consumption by 20% ~ 30%, and can improve the preparation of environmentally friendly desulfurization limestone powder.
Post time: Nov-25-2021
