Drying calcinatory especially suitable for synthetic gypsum

Abstract

The invention discloses a drying calcinatory especially suitable for synthetic gypsum, which comprises a horizontally arranged cylindrical casing, wherein the casing is arranged between an air exhaust barrel and a discharging barrel in rotary mode, is connected with a motor by aid of a transmission mechanism and can be driven by the motor to rotate. A raising plate is slantingly arranged on the inner wall of the casing. A feeding mechanism is further arranged at the feeding end of the casing. The drying calcinatory especially suitable for synthetic gypsum further comprises a heating air pipe forwards arranged inside the casing, wherein a plurality of air exhaust holes are arranged on the heating air pipe and divided into a first row of air exhaust holes, a second row of air exhaust holes and a third row of air exhaust holes with distribution density reducing sequentially in the advancing direction of materials. The drying calcinatory especially suitable for the synthetic gypsum is designed specially aiming at technology requiring conditions of drying and calcining synthetic gypsum to be semi-hydrated gypsum, can well translate synthetic gypsum into semi-hydrated gypsum, and has the advantages of good translation effect, high work efficiency, high heat use ratio and good energy conservation performance.

Description

technical field [0001] The invention relates to a calciner, in particular to a drying calciner especially suitable for desulfurized gypsum. Background technique [0002] Gypsum, whose main component is calcium sulfate, includes natural gypsum and industrial by-product gypsum. Industrial by-product gypsum is a by-product of some industrial production processes. At present, the cumulative stock of industrial by-product gypsum has exceeded 300 million tons, of which desulfurization gypsum can reach more than 50 million tons. In this way, a large amount of desulfurization gypsum is piled up, which not only occupies land, but also wastes resources. The acid and other harmful substances contained in it are likely to pollute the surrounding environment, which has become an important factor restricting the sustainable development of my country's coal-fired unit flue gas desulfurization enterprises. According to statistics, in 2009, my country's industrial by-product gypsum produced...

AI Technical Summary

Problems solved by technology

[0005] 1. Most of them adopt airflow drying method: that is, drying and calcination are carried out in one shell at the same time. The advantage is that the gypsum powder is heated in a short period of time, and the powder can be heated in all directions under the action of hot airflow to achieve drying. The purpose; its disadvantages are large energy consumption, high equipment cost, and low output; especially in the same shell, the material is first exposed to high-temperature dry air, and after drying the surface moisture of the material, it is then exposed to low-temperature wet air. The advanced process equipment is not conducive to the calcination of gypsum crystal water, and the temperature at the exhaust gas discharge point is often about 140-160 degrees, and the energy consumption is quite high; that is, 150 kg of standard coal is required to produce one and a half tons of water gypsum; The dryer relies on the blower to send the hot air and gypsum powder to the drying pipeline. The height of the pipeline usually needs to be 13-20 meters high and the diameter is 1 meter; it must be realized with a larger blower; the power consumption is quite large; The installed capacity of this blower is as high as 180-240 kilowatts

Therefore, the cost of producing industrial by-product gypsum hemihydrate gypsum with airflow dryer is too high

[0006] 2. Using a rotary drum dryer: the drying of the rotary drum dryer is to lift the gypsum powder through the lifting plate in the drum when the drum is rotating, and under the action of the exchange of hot air, the gypsum material is carried out. Drying and calcining; drying and calcining with hot air flowing opposite to the direction of movement of gypsum powder is called downstream drying and calcining; the other is drying and calcining with hot air flowing opposite to the direction of movement of gypsum powder, which is reverse drying Calcination method; the advantage of the rotary drum dryer is that the power consumption is small, but the coal consumption is also relatively large; the rotary drum dryer can make the dihydrate gypsum powder contact with the hot air in all directions under the action of the lifting plate , can be fully dried and calcined, but its air flow direction is a single direction, which determines that the contact between the dihydrate gypsum and the hot air flow in the drum is the process of contacting the dry air before contacting the wet air, which is different from the two The drying process of water gypsum is inconsistent and unscientific

[0008] Therefore, the current air dryers and drum dryers are difficult to meet the requirements of the drying and calcination process of industrial by-product desulfurized gypsum in their hot air flow mode.

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