Phosphogypsum calciner

Abstract

A phosphogypsum calciner belongs to the field of phosphogypsum calcinations. The phosphogypsum calciner includes a fire spitting furnace, an inner cylinder, a material inlet, an outer cylinder, an outer cylinder material pushing plate, an inner and outer cylinder connecting piece, an outer cylinder tail end, a conical body, an inner cylinder material pushing plate, a pressure equalizing device anda material outlet; the fire spitting furnace is a coal spraying furnace or a gas-fired fire spraying furnace, and is mounted at the material outlet of the inner cylinder, and the fire spraying direction of the fire spitting furnace is locate at the material discharging end of the inner cylinder; the inner cylinder is arranged in the outer cylinder and is coaxial with the outer cylinder, and the outer wall of the inner cylinder is fixedly connected with the outer cylinder through the inner and outer cylinder connecting piece; and the material inlet is arranged in the outer cylinder, is locatedat one end of the fire spitting furnace, and penetrates through the wall thickness of the outer cylinder. The phosphogypsum calciner has the characteristics of keeping of the balance of airflow in the inner cylinder, uniformity in heating of the calcined material, realization of movement of the calcined material tending to be smooth, and improvement of the production efficiency and the calcination quality.

Description

technical field [0001] The invention belongs to the field of phosphogypsum calcining, and in particular relates to a phosphogypsum calcining furnace which adopts a coal-injected furnace or a gas-fired flame-injected furnace as a heating heat source and adopts double-tube rotary drums. Background technique [0002] Phosphogypsum is a by-product produced by phosphorus chemical enterprises. Due to its high water content, harmful substances and acid ions, and the main component is dihydrate gypsum, it cannot be directly applied to building construction and other occasions where gypsum is used, resulting in a large amount of accumulation , so as to cause new environmental pollution; for this reason, the inventor first invented phosphogypsum to remove harmful substances and acid ions through calcination, so that it can be converted into a complex phase hemihydrate gypsum mixture that can be used for building construction, and solve the problem of phosphorus A large amount of gypsu...

AI Technical Summary

Problems solved by technology

[0002] Phosphogypsum is a by-product produced by phosphorus chemical enterprises. Due to its high water content, harmful substances and acid ions, and the main component is dihydrate gypsum, it cannot be directly applied to building construction and other occasions where gypsum is used, resulting in a large amount of accumulation , so as to cause new environmental pollution; for this reason, the inventor first invented phosphogypsum to remove harmful substances and acid ions through calcination, so that it can be converted into a complex phase hemihydrate gypsum mixture that can be used for building construction, and solve the problem of phosphorus A large amount of gypsum accumulation causes environmental pollution, and at the same time, it provides high-strength and water-resistant gypsum building materials for construction; at present, the calciner used is a rotary kiln-type double-barrel calciner, and the backfire calciner is used. The method is to feed the material at the end of the outer cylinder of the calciner located at the flame-injection furnace. With the rotation of the drum, under the action of the pusher plate, the gypsum powder moves from one end of the flame-injection furnace to the other end, and then moves to the end of the outer cylinder. After entering the inner cylinder through the cone, the gypsum powder moves from the far end of the inner cylinder to the near end of the flame-throwing furnace, and the flame-throwing furnace needs strong wind assistance when spraying fire, so that the heat of the flame can be sprayed to the deep part of the inner cylinder. To achieve the purpose of calcining gypsum; due to the requirements for the length of the flame-throwing furnace, the nozzle diameter of the flame-throwing furnace is limited, that is to say, the diameter of the flame-throwing furnace cannot be infinitely enlarged, and the difference between the diameter of the inner cylinder and the diameter of the flame-throwing furnace is not the same When it is large, the fire sprayed by the flame-breathing furnace can take into account the overall wind of the inner cylinder section, and at the same time, there is no need to increase the wind pressure of the flame-breathing furnace; It cannot be expanded infinitely, because the flame-breathing effect cannot be formed if the diameter of the flame-breathing furnace exceeds the limit. In order to meet the large-diameter inner tube with large gypsum capacity and high output, it is necessary to increase the fire-breathing wind. Because the mouth of the flame-breathing furnace is small, The flame or hot air flow from the flame-injecting furnace is concentrated in the central area of ​​the inner cylinder section corresponding to the nozzle diameter of the flame-injecting furnace. Therefore, a hot air column will be formed in the central area of ​​the inner cylinder section. Particles, the hot air column can blow these fine particles to the far end of the inner cylinder and then return to the outer cylinder, which cannot ensure smooth entry into the calcination area near the flame-breathing furnace, or stop advancing after entering the calcination area, resulting in over-burning and scrapping, which is harmful to the control The calcination quality and output of phosphogypsum have a great impact, the result is no material or less material, or the material is burned to death

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