Maintenance measures of clay refractory bricks for coke ovens mainly include the following aspects:

I. Daily inspection and cleaning

Regular inspection: check all parts of the coke oven every day, focusing on whether there are cracks, peeling and deformation in the furnace wall, roof and oven door.

Cleaning and maintenance: regularly clean impurities such as dust, tar and graphite on the furnace surface to prevent their accumulation from causing uneven surface temperature or chemical erosion of refractory bricks.

II. Hot repair

Hot patching: For cracks, spalling and other damages on the furnace wall of the carbonization chamber, hot patching refractory mud can be used for patching. This material can be closely combined with the furnace wall brick at high temperature, and the material hanging time is long after repair, and the repair surface is flat.

Shotcrete method: For a large area of damage, semi-dry gunning method can be used. The gunning material is sent to the nozzle by compressed air, mixed with adhesive and sprayed on the wall, and the hanging time after repair can reach 6-12 months.

Ceramic welding repair: For the severely damaged parts, ceramic welding repair method can be used to fuse the repair and refractory bricks at high temperature, but this method is costly.

III. Temperature control and insulation measures

Temperature control: During hot repair, it is necessary to cool the repair parts in advance to ensure the proper temperature during the repair process. For example, when the brick at the bottom of the coke oven carbonization chamber is hot-mended, the furnace temperature should be reduced to 800-900℃ and the furnace head temperature should be controlled at 800-850℃.

Insulation measures: During the repair process, insulation brick retaining wall or insulation felt can be set around the repair site to ensure that the wall temperature is higher than 700℃ and reduce the influence of temperature difference on the refractory bricks.

IV. Material Selection and Construction Quality

Refractory mud: Choose suitable refractory mud, such as clay phosphoric acid mud or high-alumina clinker binder, to ensure the performance matching between repair materials and refractory bricks.

Construction quality: when repairing, it is necessary to ensure that the refractory mud is evenly spread, the brick joints are full and the repair surface is flat. For the laying of new bricks, it is necessary to leave appropriate expansion joints to prevent damage caused by thermal expansion and contraction.

V. Other maintenance measures

Sealing treatment: the top area, the pipe socket of the riser bridge and the furnace wall of the coal charging chamber are sealed to prevent gas leakage and heat loss.

Regular replacement: For severely worn refractory bricks, they should be replaced in time to avoid local damage affecting the service life of the whole furnace body.

Through the above maintenance measures, the service life of clay refractory bricks for coke oven can be effectively prolonged, the maintenance cost can be reduced, and the stable operation of coke oven can be ensured.