Fluidized bed gasifier and its application

Abstract

The invention discloses a gasifier of a fluidized bed and use thereof. The gasifier of the fluidized bed comprises a gasifier body, a synthesized gas outlet, a material input pipe, a gasifying agent nozzle, an auxiliary gasifying agent input pipe and a plasma torch which are positioned on the gasifier body, and the gasifier of the fluidized bed is used for gasifying ungasified material and residual carbon in ash for the second time. By virtue of the gasifier adopting the above technical scheme, the temperature inside the gasifier can be effectively raised, the coal type adaptation of the gasifier of the fluidized bed is widened, the content of effective ingredient in the synthesis gas is improved, the content of carbon dioxide and methane is reduced, the level of residual carbon in the ash is reduced, the carbon conversion rate and gasification efficiency are improved, the operation stability and reliability of the gasifier are improved. The gasifier of the fluidized bed provided in the invention has the advantages of wide coal type adaptation, high carbon conversion rate, high gasifying efficiency and reliable operation.

Description

technical field [0001] The invention relates to the technical field of coal gasification, in particular to a fluidized bed gasification furnace and its application. Background technique [0002] At present, the commonly used coal gasification technologies in the domestic coal gasification field can be classified into three types, namely, fixed bed (moving bed) gasification technology, fluidized bed gasification technology and entrained bed gasification technology, and each gasification technology includes Different types of gasifiers. Fixed bed gasification technologies mainly include pressurized Lurgi furnace, atmospheric pressure UGI furnace (coal gasifier named after United Gas Improvement Company), etc., which require the use of lump coal or briquette coal for gasification. Entrained gasification technology mainly includes dry coal powder and coal-water slurry pressurized gasification technology. Representative furnace types include Shell dry powder furnace and GE (Gene...

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Problems solved by technology

[0003] However, the current fluidized bed gasifiers all use solid-state slag discharge technology, and the ash in the gasifier is discharged through the furnace bottom ash discharger.

This method of slag removal requires that the ash should be loose and cannot be scarred into large pieces, otherwise it will affect the normal operation of the gasifier. The problems brought about are: first, it limits the selection of coal types for the gasifier, and requires a relatively high melting point of coal ash. High, weak adhesion, high activity, second, the gasification temperature in the gasifier is limited, and the operating temperature is required to be 100-200°C lower than the ash melting point, so the residual carbon content in the ash residue is relatively high, and the carbon dioxide and carbon dioxide in the syngas Higher methane content affects the yield and quality of synthesis gas, which also has an adverse effect on the subsequent ammonia synthesis section

The third is that in the operation of the gasifier, it is sensitive to changes in coal quality and operating parameters, which affects the operation or production efficiency of the gasifier

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