Construction process of refractory brick for fire passage wall of carbon roaster

The masonry quality of refractories for roasting furnace has a direct impact on the whole roasting operation, process and service life of roasting furnace. Therefore, the construction of amorphous refractory materials such as refractory bricks, castables and refractory mud must be carried out in strict accordance with the construction standard process and relevant specifications to ensure the construction quality.

The refractory materials for roasting furnace shall be orderly entered into the construction site and stored properly before construction. The quantity and quality of refractory materials entering the site shall be strictly checked. Unqualified refractory materials are prohibited from entering the site to ensure that they meet the design and construction requirements.

Refractory materials for roasting furnace have entered the construction site, and the refractory materials are hoisted to the construction area in batches. Before masonry, the vertical and horizontal centerline and elevation of the furnace body shall be measured, checked and marked for many times. For furnace bottom leveling, take the design elevation of roasting furnace as the benchmark, measure the label of each furnace chamber, determine the leveling thickness, and use cement mortar for leveling. After the mortar is solidified, set out and mark the refractory brick masonry line according to the center line of each row of furnace chamber and the center line of transverse wall, and prepare to start masonry after the size is checked to be correct.

The refractory construction specification of fire passage wall shall be sorted and shared by the refractory manufacturer.

  1. Furnace bottom construction:

The furnace bottom is mainly composed of lower furnace bottom, insulation layer and bottom plate brick.

Construction of lower furnace bottom: build brick piers longitudinally with clay brick standard bricks, and cover the surface with castable precast blocks to form an overhead furnace bottom;

Insulation layer: 1 ~ 5 layers of masonry, wet masonry with 0.7 diatomite light insulation brick; 6 ~ 8 layers of masonry, using 0.8 light high aluminum insulation brick;

Bottom plate brick: special shaped clay brick is used for masonry in two layers, and the masonry thickness of each layer is in accordance with the design requirements. For masonry, the brick layer line shall be drawn according to the elevation of the upper layer of the furnace bottom, and then the masonry datum line shall be marked by pulling a line.

The refractory slurry used for bricklaying requires that the material shall match the masonry, and the staggered masonry shall be carried out. The refractory slurry filling shall be full and dense.

  1. Furnace wall masonry:

Furnace wall masonry can be divided into peripheral wall masonry and transverse wall masonry.

Peripheral wall masonry: first set out the masonry line according to the center line, and strictly control the elevation of each layer during masonry to avoid cumulative deviation in the end. Conduct random inspection on the flatness and verticality of masonry from time to time. The thickness of the reserved expansion joint shall be reserved according to the construction requirements, and the filling shall be dense and full. When the dryness of the wall is about 7 floors, clean it.

Horizontal wall masonry: during masonry, due to the different brick types used for the horizontal walls on both sides of the end and the middle horizontal wall, the masonry personnel shall be familiar with the design drawings and carry out masonry in strict accordance with the construction scheme. The first layer shall be pre laid with dry laid refractory bricks, and the groove of fire passage wall shall be reserved. The elevation of the 40th floor of the transverse wall is 1 ~ 2mm lower than that of the 40th floor of the fire passage wall. During the masonry process, double-sided lines shall be drawn, and the perpendicularity of the wall shall be adjusted and controlled by the stay wire on the side wall. The thickness of the reserved expansion joint between the transverse wall and the side wall shall meet the design drawings, and the filling shall be dense and full.

  1. Masonry of fire passage and connecting fire passage:

The masonry of fire passage wall shall be carried out in strict accordance with the design drawings. The formal masonry shall be started after the pre laid dry laid bricks are inspected to be qualified. During the masonry of fire passage wall bricks, the two adjacent bricks shall be naturally close, and the reservation of expansion joint shall meet the design requirements. The masonry personnel shall be familiar with the construction drawings and prepare the bricklaying drawings. The number of masonry layers per day shall not exceed 13, and pay attention to the natural settlement cycle. Attention should be paid to the characteristics of more brick types and no refractory slurry filling in the vertical joints during the masonry construction of fire passage wall.

Before construction, the foundation elevation and center line of the roaster shall be checked for many times, the maximum negative error shall be found out, and the dry sand and refractory brick shall be used for repair and leveling. The masonry must be carried out according to the setting out size, and the elevation of the furnace wall must be strictly controlled. During the masonry, the flatness of the large wall shall be checked for many times from time to time and leveled in time. The thickness of the expansion joint shall be reserved according to the design requirements. The brick slag and sundries inside the expansion joint shall be removed before filling with fire-resistant slurry. The brick joints and vertical joints of the masonry under the fire channel capping brick shall not be filled with fire-resistant slurry, and the vertical joints of the masonry wall close to the big wall of the side fire channel shall be filled with fire-resistant slurry.

The precast block of castable shall be fabricated before installation, and the overall dimension error of the precast block shall be within ± 5mm. The masonry of connecting fire path can be carried out independently or synchronously with the end transverse wall. During the construction process, pay attention to the masonry quantity, position and quality of thermal insulation layer, and carry out the next construction after passing the inspection.

  1. Furnace top pouring material construction:

First install the embedded parts on the furnace top, starting from the upper part of the connecting fire passage, then hoist the precast block of castable on the wall of the fire passage, and finally install the precast block on the upper part of the transverse wall. When installing the prefabricated block on the upper part of the fire passage, the bottom of the castable shall be filled with zirconium containing refractory fiber insulation board with the allowable thickness. Then start the pouring construction of the castable, mix it evenly, and then tamp it with mechanical vibration while pouring. The castable shall be poured at one time within 30 minutes before the initial setting.