Method for producing grey bricks by utilizing a tunnel kiln, bell jars and box-type lifting kilns

Abstract

The invention relates to a grey brick sintering method, in particular to a method for producing grey bricks by utilizing a tunnel kiln, bell jars and box-type lifting kilns. The method comprises: a raw material crushing process, a green body forming process and a green body drying process, and further comprises a product preheating process, an oxidizing roasting process, a reducing roasting process, a water-adding cooling process, a heat-extracting cooling process and a grey brick discharging process. A preheating region, a sintering region and a temperature-preserving region are sequentially arranged in the tunnel kiln. Green bodies are preheated and then are subjected to oxidizing roasting in the funnel kiln; brick products subjected to oxidizing roasting are covered with the bell jars and are transferred into the box type lifting kilns through a transfer car so as to be subjected to reducing roasting; the grey brick products which are cooled to 900-1000 DEG C are led out of the box type lifting kilns, and are quickly covered with the bell jars, and water is added into the bell jars to cool the grey bricks to 400-500 DEG C; and the green brick products with the temperature lower than 400-500 DEG C are cooled to a normal discharging temperature through the heat-extracting cooling kiln. The method is simple and convenient in operation, high in production rate, low in energy consumption, environmentally-friendly and pollution-free, and short in production period; and products are quick to transform, high in compactness, and resistant to compression and wear.

Description

technical field [0001] The invention relates to a method for firing blue bricks, in particular to a method for producing blue bricks by using a tunnel kiln + a bell jar + a box-type lifting kiln. Background technique [0002] The blue bricks are refined from natural clay, and the products after firing are blue-black, with the characteristics of high density, good frost resistance, no deformation, and no discoloration. [0003] The traditional green brick firing process mainly uses clay as the main raw material. After the clay is mixed with water, it is extruded and shaped, then fired in a brick kiln, and finally cooled with water to incompletely oxidize the iron in the clay, so that it has better durability. Weathering, water resistance and other characteristics. However, this firing process has high requirements on land occupation, and the qualified rate of finished products and production efficiency are low. Taking the production of 30,000 sintered green bricks as an exam...

AI Technical Summary

Problems solved by technology

However, this firing process has high requirements on land occupation, and the qualified rate of finished products and production efficiency are low. Taking the production of 30,000 sintered green bricks as an example, the length of the kiln body of a traditional tunnel kiln is at least about 80m, and the firing cycle Generally, it takes 10 days; while the traditional downdraft kiln is used to burn blue bricks, taking 12,000 standard bricks per kiln as an example, the firing cycle is about 15 days, covering an area of ​​about 40 mu

[0004] Application No. 201410587248.2 discloses a method for firing blue bricks using a split tunnel kiln. Although this method solves the problems of high land occupation requirements, low qualified rate of finished products and low production efficiency of the traditional green brick firing process to a certain extent, However, it still has disadvantages: (1) Positive pressure is generated in the kiln during reduction firing, and the kiln car canal is not tightly sealed, resulting in excessive heat loss and high energy consumption; (2) High-temperature reduction firing is harmful to the kiln car High temperature oxidative damage is caused, which reduces production costs; (3) The problem of wind and fineness occurs when the semi-finished product is transferred; (4) The heat loss is too large, which reduces the production yield; (5) The cooling is too slow, the product temperature is high, and the extension The time out of the kiln is shortened, and the production cycle is long

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