Checker Bricks in Coke Oven

Coke oven checker bricks play a vital role in the coke oven system. They are designed to absorb and release heat with high efficiency, transferring the heat of the exhaust gas to the cold air or blast furnace gas through the heat exchange process in the regenerator, thereby significantly increasing the temperature of these gases. This process not only helps to reduce the gas consumption required for coke oven heating, but also reduces energy consumption and carbon emissions in the coking process.

How do Checker Bricks Work in Coke Oven Systems?

Specifically, checker bricks work in the following ways:

‌Heat exchange‌: During the combustion process, when the hot exhaust gas passes through the regenerator, the checker bricks absorb most of the heat, significantly reducing the temperature of the exhaust gas. Subsequently, when the cold air or blast furnace gas passes through the regenerator, the checker bricks release their stored heat, preheating these gases to above 1000℃.

Reduce energy consumption and emissions‌: Through this heat exchange process of rising and falling airflows, the coke oven can effectively recover and utilize heat, thereby reducing dependence on external heat sources, reducing energy consumption and carbon emissions.

Maintain uniform furnace temperature‌: The unobstructed and good heat storage capacity of the regenerator is essential to maintaining uniform furnace temperature, which is of great significance for reducing production costs and reducing environmental pollution.

In summary, coke oven checker bricks, through their unique heat exchange mechanism, not only improve energy utilization efficiency, but also contribute to environmental protection, and are an indispensable component of the coke oven system.

Construction steps and methods for coke oven heat storage chamber masonry

Laying of sliding layer in coke oven heat storage chamber

1. Build the foundation platform first, adjust and correct the resistance wall, and prepare to lay the sliding layer after passing the inspection.
2. When using river sand to lay the sliding layer, the river sand must be flat and uniform in thickness.
3. A layer of petroleum asphalt felt must be laid between the refractory bricks and the river sand sliding layer before masonry.
4. When using thin steel plates as sliding layers, the following requirements should be observed:

• • (1) The sliding layer should be laid once before bricklaying, and the bottom of the steel plate should be coated with yellow dry oil before laying.
  • (2) After the steel plate is laid and inspected and passed, apply a thin layer of yellow dry oil on the surface of the steel plate, then lay a layer of petroleum asphalt felt, and then lay bricks.
  • (3) It is strictly forbidden to recycle mud with oil stains.

Bricklaying process of small flue and regenerator wall in coke oven regenerator

1. Before laying the small flue, mark the width edge of each wall at the center line mark of the combustion chamber, and mark the height line of each brick layer on the vertical pole. You can also use the method of measuring and laying out the lines by wall.
2. The first layer of masonry of the small flue should be pre-laid dry. After checking that the width of the reserved expansion joint is qualified, lay out the lines to lay out the furnace head of the main wall of the small flue.
3. The furnace head position needs to be laid several layers of bricks at a time, and the wall should be stepped to prevent the furnace head from shifting on the sliding layer.
4. During masonry, check and verify the horizontal and vertical degree of the masonry according to the center line many times to prevent the furnace wall from twisting.
5. The masonry process should be cautious and careful, and the furnace head position should not collide. When changing shifts, first check and confirm whether the furnace head position has been moved and make adjustments.
6. Check the straightness of the masonry wall at any time. After the small flue wall is completed, check the brick layer elevation and gradually level it.

Laying process of lining bricks and grate bricks in coke oven regenerator

1. Lay the center partition wall first, and then lay the lining bricks after the masonry is completed and the construction area is cleaned. The laying order should be from the center to both sides.
2. Lay yellow cardboard when laying bricks, and use wooden supports to fix the lining bricks after they are laid to ensure that the width of the expansion joint between the lining bricks and the furnace wall does not change during laying.
3. After the lining bricks are laid, clean the bottom and wall of the small flue, lay a layer of 10-15 mm clean sawdust at the bottom of the small flue, and then lay the grate bricks layer by layer from the center to both sides. The refractory mud squeezed out of the brick seams of the brick layers should be cleaned at any time.
4. When laying grate bricks with holes, strictly check the aperture of the grate bricks, and then lay them after they are qualified. When laying grate bricks in air and gas regenerators, first carry out pre-laying dry laying and seam inspection respectively, and then formally lay them.
5. Use a wooden ruler to check the straightness of the grate brick leg platform. The gap error should meet the construction requirements.
6. After the grate brick is laid, clean the expansion joint and inspect it. If it is qualified, lay a wooden protective plate on the grate brick. The gap between the protective plate and the wall shall not exceed 15 mm.

Coke oven heat storage chamber wall brick laying process

1. Use the matching refractory mud for the corresponding masonry according to the design drawings. When changing the refractory mud material, the preparation utensils should be cleaned.
2. According to the elevation mark of the gas pipe brick, start from the first gas pipe brick on both sides of the furnace head, and then lay the gas pipe bricks in other parts in sequence.
3. During the laying process, the center distance between the gas pipe bricks should be corrected using a standard plate, and the length of the standard plate should be greater than half of the furnace length. The vertical center line of the coke oven, the front line and the center position of each gas pipe in between should be marked on the standard plate. The flatness of the masonry should be checked and aligned every two layers.
4. The refractory mud in the mortar joints of the gas pipe bricks should be filled full and dense, and the refractory mud entering the pipe brick hole should be cleaned. Before the end of work every day, the gas pipe bricks should be thoroughly cleaned from top to bottom to ensure that the gas pipe bricks are unobstructed.
5. The location of gas pipe bricks should be checked at any time during the construction, and the gas pipe bricks should not be collided or twisted when the heat storage room wall bricks are laid.
6. The central partition wall should be built after the main single wall is built to a certain height (generally not more than 1.2 meters). During the construction, expansion joints and sliding joints should be reserved according to the construction design requirements, and the filling should be full and dense.
7. The elevation between the main wall of the heat storage room and the adjacent single wall, between the main wall and the adjacent main wall, and between the walls should be checked frequently to keep them consistent.

Laying process of checker bricks in coke oven regenerator

1. After the furnace body is laid, blow and clean the secondary grooves on the top of the regenerator cover, and mark the control line between the central partition wall and the sealing wall on the regenerator wall.
2. Use compressed air to blow the checker bricks clean and start preparing to lay the checker bricks.
3. When the first layer of checker bricks is dry-laid, check the placement and stability of the checker bricks before the lower layer of checker bricks can be dry-laid.
4. The checker brick layers after the second layer should be stepped back from the central partition wall to the furnace head for dry-laying.
5. Frequently check the lattice holes of each layer of checker bricks for smoothness, and the upper and lower layers of checker bricks should be aligned.
6. Yellow cardboard can be used to maintain the gap width and stability between the checker bricks and the regenerator wall, and non-flammable materials must not be used as padding.
7. After the dry-laying of checker bricks in each regenerator is completed and the inspection is qualified, start laying the regenerator sealing wall.
8. The regenerator wall and checker bricks of the sectional regenerator coke oven should be laid alternately in sections. Before each section of checker bricks is laid, the sealing wall or partition wall of this section should be completed first, and the grooves on the wall should be cleaned. During the dry laying of checker bricks, pay attention to prevent the refractory mud from falling into the checker bricks of the next section. After the dry laying is completed and the inspection is qualified, immediately cover the protection plate. The protection plate should be set firmly and tightly, close to the wall of the regenerator to prevent the refractory mud from leaking into the checker bricks.