Checker fire bricks refers to the lattice masonry made of refractory bricks in the regenerator. The regenerator must have a large enough lattice volume and heating area to make full use of the waste heat and promote the preheated gas to reach a higher preheating temperature. There are many ways to build the lattice. In terms of technology, it has the following requirements: it can make full use of the volume of the regenerator, has large heating area and heat storage capacity, has high preheating gas temperature and small fluctuation, has uniform air distribution, high heat transfer efficiency, small air flow resistance, is resistant to high temperature erosion, has stable structure, and is convenient for cleaning and maintenance.
The checker fire bricks used for lattice masonry is also called checker fire bricks, which refers to the refractory brick used for building the regenerator lattice. The intermediate medium for heat exchange (heat storage and heat release) between high-temperature exhaust gas and preheated gas in the regenerator. The checker fire bricks is required to have certain corrosion resistance and thermal shock resistance stability. Common checker fire bricks materials include fireclay brick, high alumina brick, magnesia brick, magnesia peridotite brick, chrome magnesia brick and zirconia corundum brick. Different bricks can also be used according to the height of the lattice, so as to improve the service performance of the lattice. The brick type can be standard or special shaped bricks.
The working principle of the glass kiln regenerator is as follows: when the high-temperature waste gas in the kiln enters the regenerator from top to bottom through the small furnace mouth and the air and gas channels, the regenerator lattice will be heated, and the lattice temperature will gradually increase to accumulate heat: after the fire change, the combustion supporting air and gas will enter the regenerator from bottom to top through the bottom flue of the regenerator, and the heat stored in the lattice volume will preheat the air and gas, and the lattice temperature will gradually decrease to realize waste heat recovery, Ensure that the flame has sufficient temperature to meet the requirements of glass melting.
There are many structural forms of glass furnace regenerators, which can be divided into the following types according to whether the regenerators are connected or not.
(1) Connected structure
The air regenerator under the small furnace on one side of the furnace is a connected chamber, and the gas regenerator is also a connected chamber. Due to uneven air distribution, this form is easy to form local overheating, which will quickly burn out the checker fire bricks. At present, it is no longer used.
(2) Separated structure
The regenerator at one side of the furnace is divided into several independent chambers with each small furnace disconnected from each other. The gas distribution is adjusted by the ram on each branch flue and is connected with the gas and air branch flue respectively. The structure is characterized by convenient gas distribution and adjustment and good hot repair conditions, but the partition wall occupies more space and reduces the effective volume of the lattice. But it is one of the most commonly used methods.
(3) Semi separated structure
It means that the flue below the regenerator grate is separated by each small furnace, the regenerator itself is not divided, and the gas distribution regulating gate is still on the branch flue.
(4) Separated structure of two small furnaces
The structural form is that each two small furnaces share a regenerator or are separated into a regenerator, and the branch flue is separated according to each small furnace, so as to facilitate the adjustment of the gas distribution of each small furnace. This structure is between separated and semi separated. Because of its stable structure, convenient operation and high heat conversion efficiency, most manufacturers adopt this structure at present.
(5) Two section structure
The structure divides a single regenerator into two regenerators, which are separated by partition walls and connected by a vertical channel, that is, the regenerator is divided into high-temperature zone and low-temperature zone. This structure is mainly used to prevent the corrosion of checker fire bricks by the gas, liquid and solid conversion of sodium sulfate, so that the conversion is carried out in the connecting channel of the regenerator, so as to extend the service life of checker fire bricks. However, this type of regenerator has a complex structure and is rarely used.