1. Optimize the design of kiln mouth structure
The kiln mouth structure is improved. The number of guard irons remains unchanged, and the connection method of the guard irons is changed from the original single-piece connection to a box-type connection, that is, it consists of an inner guard iron and an outer box, and the kiln barrel is located between the two, connected as a whole with countersunk bolts, and the outer box is filled with refractory castables to protect the fixing bolts and the barrel from high-temperature burning and deformation. The thickness of the castables on the straight wall below the kiln mouth is appropriately thickened to ensure that the end face of the kiln mouth shrinks inside the straight wall without affecting the clinker falling into the grate cooler, so as to avoid the kiln mouth being directly eroded and burned by the high-temperature hot flue gas of the grate cooler.
2. Strictly control the quality of castable construction and make corresponding improvements
(1) In order to increase wear resistance, the effective thickness of the castables above the kiln mouth guard plate is increased from 160mm to 220mm.
(2) Reasonably arrange the anchor nails, and use materials with relatively large welding areas for the anchor nail structure.
(3) When pouring the kiln mouth refractory castable, the principle of supporting the formwork first and then constructing should be strictly followed. All pouring must be completed at the 7 or 9 o'clock position on the circumference.
(4) The castable must be mixed evenly and mixed immediately after use. The moisture content should be kept at the lowest value and a dedicated person should be responsible for mixing.
(5) Based on practical experience, expansion joints are set with 3mm plywood for every 600mm length. All anchor nails should be painted with asphalt paint and wrapped with black tape to compensate for their expansion space.
(6) The castable material is changed to a special castable for the kiln mouth to improve high temperature resistance and vibration resistance.
(7) Abandon the original maintenance thinking. When conditions permit, the construction of the kiln mouth refractory castable should be given priority every time the maintenance is carried out, and the curing time of the castable should be extended as much as possible.
3. Improve the ventilation of the kiln system to ensure a slight negative pressure on the kiln head cover
(1) Improve the ventilation of the kiln tail slope. The total thickness of the original slope refractory material is adjusted from 250mm to 200mm AZM1680 silica-molybdenum brick masonry.
(2) Improvement of kiln head system. In view of the actual situation that the kiln head exhaust fan has a relatively small processing capacity, the air leakage of the kiln head system is reduced as much as possible, thereby improving the kiln head's air volume processing capacity to basically meet production requirements.
