Powder granulation technology, as a main branch of powder and granular processing, has become increasingly important with the increase in environmental protection requirements and the automation of the production process. The significance of granular strength processing for powdered products is mainly reflected in three aspects:
1. Reduce dust pollution and improve working conditions.
Second, to meet the requirements of the production process, such as increasing the porosity and specific surface area, improving heat transfer, etc.
3. Improve the physical properties of the product (such as fluidity, air permeability, bulk density) to avoid segregation, pulsation, agglomeration, bridging, etc. in the subsequent operation process (drying, screening, metering) and use process (metering, batching, etc.) Adverse effects, reducing pollution, improving appearance, improving fluidity, facilitating storage and transportation, controlling solubility, controlling porosity and specific surface area, etc., create conditions for improving the automation of production and use processes and sealing operations.
DH series dry rolling granulator adopts dry rolling process technology to compress powdery materials with moisture content ≤5% into flakes or blocks, and then crush the granules and sieving process to make the flakes into blocks. The material becomes a granular material that meets the requirements of use. Dry rolling granulation mainly relies on external pressure to force the material to pass through the gap between two oppositely rotating rollers and forcibly compress into pieces. During the rolling process, the actual density of the material can be increased by 1.5 to 3 times. So as to achieve the specified particle strength requirements.
The raw materials are evenly fed into the feeding hopper through a quantitative feeder. The compactor uses a pair of rollers with holes, leaving a certain gap between them, and the two rotate in opposite directions at the same speed. One set of roll chocks does not move in the rack, while the other set of roll chocks moves upstream on the rack guide rail, and presses against each other by hydraulic cylinders. Many holes of the same shape and size are regularly arranged on the surface of the roll, and the troughs are aligned with the troughs. At this time, the dry powder material enters between the two rollers continuously and uniformly from the top of the two rollers by its own weight and forced feeding. The material first flows freely, and after entering the biting area, the rollers gradually bite into the trough. With the continuous rotation of the roll, the space occupied by the material is gradually reduced and gradually compressed, and the maximum molding pressure is reached. Then the pressure is gradually reduced, and the pressed blocks fall off the holes due to elastic recovery and their own weight, and enter the crushing and sieving device. The finished product is a granular qualified product and is weighed and packaged. The fine powder and unqualified super-large particles from the powder inlet will be re-entered into the feed inlet of the hoist by the return auger and mixed with fresh materials into the pre-feeding hopper to enter the next round of the process flow.
◆Without any additives, the dry powder can be directly granulated;
◆The particle strength can be adjusted, and the strength of the finished product can be controlled by adjusting the pressure of the roll;
◆Circular operation, continuous production, high output of finished products;
◆The material is forced to be compressed and molded by mechanical pressure, without any additives, and the purity of the product is guaranteed.
◆Dry powder is directly granulated without subsequent drying process, which is more conducive to the connection and transformation of the existing production process.
◆The granule has high strength, and the increase of the bulk density is more significant than other granulation methods. It is especially suitable for the occasions where the bulk density of the product is increased.
◆It is suitable for a wide range of raw materials, and the particle strength can be adjusted freely according to different materials.
◆Compact structure, convenient maintenance, simple operation, short process flow, low energy consumption, high efficiency and low failure rate.
◆Environmental pollution can be controlled, powder waste and packaging cost can be reduced, and product transportation capacity can be improved.
◆The feeding and feeding device adopts variable frequency stepless adjustment and control, which has a high degree of automation, which can realize multi-machine control by one person, and has the characteristics of low labor intensity and long-term continuous operation.
◆The main transmission parts are made of high-quality alloy materials. The production of stainless steel, titanium, chromium and other surface alloys greatly improves the wear resistance, corrosion resistance, high temperature resistance and pressure resistance, so that the machine has a longer service life.
Dry powder enters the raw material silo of the elevator through screw conveyor, belt conveyor or manual transportation. The bucket elevator sends the raw material powder to the vibrating transition silo, and the material is evenly fed into the frequency conversion forced feeder through the quantitative feeding device. The material is degassed and pre-compressed. The pre-compressed material is pressed between two opposing pressure rollers for compaction. The compacted strip material is automatically de-troughed and then crushed, and is powdered into particles of uneven size. Then it enters the double-knife granulator for trimming. The trimmed particles pass through the sieving. The product particles are packed or transported into the finished product silo. The sieved powdery materials are fed into the raw material hoist through the return device for the second time. Processing.