Entrained flow coal gasification method employing solid state slag-tap suitable for high ash content and high ash melting point coal

Abstract

The invention provides a coal gasification method employing solid state slag-tap suitable for high ash content and high ash melting point Huainan coal. According to the invention, the gasification reactor temperature is controlled higher than 1100 DEG C and lower than the softening temperature of the high ash melting point coal. Through adjusting the ratio of gasification reactor height and diameter, the included angle of gasification reactor cone part and gasification reactor vertical housing part, the ratio of gasification reactor interior diameter and slagoff port diameter, the ash slag is discharged as solid state without fluxing medium. The method greatly reduces the operation temperature of the gasification reactor, prolongs the service life of fittings in the gasification reactor with little heat dissipation and low demand of refractory materials grade in the gasification reactor, simultaneously reduces the specific oxygen consumption and specific coal consumption, thereby not only saving cost but also saving resource.

Description

【Technical field】 [0001] The invention relates to the field of coal gasification, and more specifically, the invention relates to an entrained-bed coal gasification method using solid-state slag removal for coal with high ash content and high ash melting point. 【Background technique】 [0002] my country's energy resource structure is dominated by coal, and coal with high ash content, high ash melting point or both high ash content and ash melting point occupies a considerable share in the existing coal. Among them, Huainan coal in Anhui Province is particularly prominent, which is rich in coal resources and has a prospective reserve of 444×10 8 tons, with proven reserves of 153×10 8 tons, accounting for about 19% of the national reserves, however, Huainan coal in Anhui Province is a coal with high ash content and high ash melting point. At present, there are relatively mature coal gasification methods, whether using dry feed or wet feed, all adopt liquid slag discharge tec...

AI Technical Summary

Problems solved by technology

Because the ash content of some coals with high ash melting point is also very high, for example, the general ash content is 8-35%, if the method of adding flux is used, it will inevitably increase the oxygen consumption, slag discharge and slag discharge heat loss to a certain extent ; If the method of increasing the gasification temperature (at this time, the gasification temperature is required to be above 1400°C), the oxygen consumption and the CO in the gas will be increased accordingly. 2 content and reduces the cold gas efficiency and the service life of the gasifier

In addition, the current coal gasification furnace is lined with refractory materials to prevent the furnace bricks from falling off due to brick laying defects, or part of the furnace bricks are thinned due to slag erosion and erosion, which will cause the local temperature of the furnace shell to be too high and cause serious accidents. Accidents, however, the refractory lining materials currently used for coal gasification furnaces cannot meet the requirements of continuous high-temperature operation above 1400 °C. Therefore, there are great limitations in specific operations to increase the coal gasification temperature; Coal blending with ash melting point coal for liquid slagging gasification operation requires mixing selective coal types with high ash melting point coal, which cannot fundamentally solve the gasification problem of high ash melting point coal

In summary, using the existing liquid slag discharge entrained bed coal gasification technology to process coal with high ash content and high ash melting point represented by Huainan coal in my country will face many problems such as large energy consumption, difficult slag discharge, and poor gasification index.

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