Waste heat boiler for recovering waste heat generated by incineration of wastes from polysilicon purification process

Abstract

The in'vention discloses a waste heat boiler for recovering waste heat generated by the incineration of wastes from a polysilicon purification process, which comprises a circulating pump, a drum, a boiler support and a boiler body arranged on the boiler support, wherein the boiler body comprises a boiler closed shell, a smoke inlet shutter, a smoke outlet shutter, a high temperature evaporator, afirst low temperature evaporator, a second low temperature evaporator, a dust removing device and a dust hopper, and the boiler closed shell has a symmetrically-distributed and mutually-independent double flue structure consisting of a left film-type water-cooled blast furnace wall, a right film-type water-cooled blast furnace wall and a 'horizontal H'-shaped frame sealed partition wall. With thedesign of symmetrically-arranged double flues, the boiler can operate through a spare flue when a flue on one side fails to work so as to ensure normal operation. The boiler is a waste heat boiler for recovering waste heat generated by the incineration of the wastes from the polysilicon purification process, which is in accordance with the properties of polysilicon smoke, meets technical requirements and is easy to repair and high in operational stability.

Description

A waste heat boiler for recovering waste heat from polysilicon purification process waste incineration technical field The invention belongs to the field of waste heat boilers of thermal engineering application technology, and relates to a waste heat boiler, in particular to a waste heat boiler used for recovering polysilicon purification process waste incineration waste heat. Background technique After the 1970s, with the deepening of people's understanding of the global energy crisis and environmental degradation, the utilization of solar energy, a renewable and clean energy, has received widespread attention, which has set off an upsurge in the development of solar cells, thus forming a series of The application and development of silicon materials is the main form, including the production of high-purity polysilicon raw materials, solar cell production, solar cell module production, and related production equipment manufacturing and other industrial chains - the photovo...

AI Technical Summary

Problems solved by technology

(3) Due to the high corrosiveness of the flue gas in the polysilicon purification process, the life of the heating surface is short, and frequent maintenance and replacement of the heating surface will often affect the normal operation of the waste heat boiler

(4) Since there is still some HCl gas in the flue gas of the polysilicon purification process, the influence of acid dew point is often not considered in the existing design of waste heat boilers, so the gas side corrosion of the heating surface is relatively serious

(5) The SiO2 dust in the polysilicon purification process is very abrasive, and the high temperature at the inlet causes the flow rate of the flue gas at the inlet to be much higher than that at the outlet. Therefore, the wear at the inlet is very serious

(6) Insufficient understanding of the bonding characteristics and coke residue characteristics of the ash in the flue gas of the polysilicon purification process, and the lack of effective ash removal devices

(7) The flue gas outlet of the waste heat boiler is connected to the filter device, but in the actual operation of the waste heat boiler, the exhaust gas temperature is often too low, which cannot meet the temperature requirements of the filter inlet

Due to the above reasons, the thermal efficiency of the existing forming waste heat boiler structure is low, the operation stability is poor, and the parameters of the outlet flue gas do not meet the requirements, which limits the development of waste recycling systems in the polysilicon preparation industry. It is necessary to invent a stable operation, The polysilicon waste heat recovery waste heat boiler with high thermal efficiency and reasonable exhaust gas temperature fills the gap in domestic polysilicon waste heat boiler technology and further improves the international competitiveness of my country's polysilicon preparation technology

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