An additive for improving high-speed railway Zhundong coal slagging characteristics and its application method

Abstract

The invention discloses an additive for improving the slagging characteristics of high-speed Zhundong coal and an application method thereof. The additive is composed of aluminum ash, dolomite and magnesium oxide, and the mass percentages are: aluminum ash 15%-65%, magnesium oxide 25%- 50%, the balance is dolomite. The application method of the additive in the present invention is to prepare mixed coal according to the mass ratio of the additive and the high-speed Zhundong coal (3-8): 100, and the mass percentage of each component in the high-speed Zhundong coal is: aluminum ash 1%-6% , magnesium oxide 1%-5%, dolomite 1%-5%. The implementation steps of the application method are: firstly determine the quality of each component of the additive according to the quality of the high-speed railway Zhundong, then crush and mix the additive and the high-speed railway Zhundong coal in a coal mill or flow and mix in a primary air duct, and finally send the additive. Burn into the furnace. The additive is composed of natural minerals and industrial wastes, and has simple components and low price. The proportion of high-speed railway Zhundong coal blending.

Description

Technical field[0001]The invention belongs to the technical field of improving the slagging characteristics of Zhundong coal, and particularly relates to an additive for improving the slagging characteristics of high-speed railway Zhundong coal and an application method thereof.Background technique[0002]With the gradual improvement of my country's economic situation, national electricity demand has continued to pick up since 2016, reaching 6791.24 billion kWh / year in 2018 (a year-on-year increase of 6.8%). China’s energy power structure is dominated by thermal power generation. In 2018, thermal power generation accounted for 73.32% of the country’s total power generation (a year-on-year increase of 6%), of which coal-fired power generation accounted for more than 90% of the total thermal power generation, indicating that coal is in China's power generation industry still dominates. In 2005, my country’s Xinjiang region discovered the largest monolithic coalfield so far, the Zhundong...

AI Technical Summary

Problems solved by technology

Therefore, there are the following problems when burning Zhundong coal: (1) The alkali metal salt sodium sulfate (melting point 884°C) is volatile, and condensation occurs when the flue gas flows to the heat exchange surface with a lower temperature, forming on the heated surface It has a viscous ash layer and continuously absorbs light components in the flue gas, which intensifies the pollution and ash accumulation; (2) The alkali metal / alkaline earth metal remaining in the Zhundong coal is easy to form a low melting point with the product of the coal combustion process Substances or low-temperature eutectics lead to a low melting point of Zhundong coal ash, and the ash particles tend to be in a molten state, which aggravates the problem of boiler slagging and reduces boiler output

In the existing technology, the silicon oxide particles and aluminum oxide particles are directly sent into the boiler furnace through the conveying device to react with flue gas to form a mixture with stable physical and chemical properties, and at the same time, the secondary air of silicon oxide and aluminum oxide particles is transported for flushing Heating surface, clean ash layer, but this method has difficulty in estimating the chemical reaction between additives and flue gas, excessive waste of silicon oxide and aluminum oxide, and difficulty in washing away the viscous ash layer on the heating surface by secondary air, etc. Potential problems; the existing technology provides an additive to improve the combustion and coking characteristics of Zhundong coal. The main components are 8 kinds of pure oxides and 1 waterproof binder. The problem with this formula is: compared with natural minerals, Pure substances are more difficult to obtain, the particle size requirements are smaller, and the price is more expensive. In actual use, it will increase the cost of burning Zhundong coal and reduce the economy of coal power

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