Stoker grates for circulating burning-up

Abstract

The invention relates to a stoker grates for circulating burning-up, wherein the existing reciprocal-type or chain-type grates are designed to be a long annular-shape with front and rear ends closed, resulting in burning-up of coal and thus overcoming the following defects of the existing coal-firing stokers: the coal remains on the grate shortly and can not be completely burn up, causing a waste of coal and low combustion efficiency.

Description

FIELD OF THE INVENTION [0001] The invention relates to a boiler stoker, specially, to the grate of horizontal circulating burning-up. DESCRIPTION OF THE PRIOR ART [0002] At present the grates for stoker-fired boiler can be classified in structure into two kinds, i.e. the reciprocating grate and the chain grate. The fuel is fed continuously to one end of the grate surface and travels horizontally across the grate as it burns. The residual ash is discharged from the opposite end. The above mentioned stoker grates have the following defects: 1) the coal is ignited mainly by means of the heat radiation from the furnace arch, the ignition begins from the upper layer towards the lower layer of the coal bed in a direction which is opposite to the direction of air flow, resulting in an unfavorable burning state and cause incomplete combustion; 2) the resident time of coal burning on the grate can not be long as the grate has a limited length, so the coal can not be fully burn up; and 3) the...

AI Technical Summary

Benefits of technology

"The present invention provides a boiler stoker for horizontal circulating burning, which overcomes the defects of existing stokers such as insufficient coal burning on the grate and high coal loss. The grate has a long annular shape structure, allowing for longer coal burning and better ignition. The invention has the benefits of improved combustion efficiency, reduced emissions, low temperature combustion, and reduced operation cost. The invention also includes a transmission unit for the grate, a chain and driven grate sheets, and a grate support with ash discharge exits."

Problems solved by technology

The above mentioned stoker grates have the following defects: 1) the coal is ignited mainly by means of the heat radiation from the furnace arch, the ignition begins from the upper layer towards the lower layer of the coal bed in a direction which is opposite to the direction of air flow, resulting in an unfavorable burning state and cause incomplete combustion; 2) the resident time of coal burning on the grate can not be long as the grate has a limited length, so the coal can not be fully burn up; and 3) the bottom layer of the coal is ignited at last, resulting in the fine coal particles to leak out from the vent slits of the grate and cause a big loss of coal.

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