this paper briefly introduces the common abnormal kiln conditions in several precalciner kilns, analyzes the causes and puts forward feasible solutions.
abnormal phenomenon 1: low burning temperature and high temperature at the end of kiln
possible causes:
(1) excessive air volume or excessive air flow in the kiln;
(2) the quality of pulverized coal is poor, the moisture content is large, the fineness is coarse, the burning speed of pulverized coal is slow, and the latter is produced;
(3) improper use of multi channel burner, unreasonable adjustment of air flow between channels, flame is not centralized;
(4) the temperature of the two air is too low.
treatment method:
(1) reduce the air volume of the system or increase the opening of the three air valve;
(2) strictly control the quality of pulverized coal and adjust the parameters of coal grinding;
(3) the flame length is adjusted reasonably so that the flame is vigorous and vigorous, and the mixture of the wind and the coal is even and the combustion is sufficient;
(4) adjust reasonable grate speed and reasonable allocation of air volume in each room.
abnormal phenomena 2: high burning temperature and low temperature at the end of kiln
possible reasons:
(1) the combustion force of burner is too strong, and the flame is bright and short;
(2) the quality of pulverized coal is good, the ash is small, the fineness is fine, and the moisture is small;
(3) the air volume of the system is too small, or the three wind does not match the air quantity in the kiln, which makes the ventilation in the kiln too small;
(4) there are rings or long thick kilns in the kiln, which affect the ventilation in the kiln, make the flame short and the temperature of the kiln end lower.
treatment method:
(1) to adjust the wind and wind ratio, reduce wind increase wind, ensure the reasonable shape of flame;
(2) the control index of pulverized coal can be within a reasonable range;
(3) increasing the air volume of the system, reducing the opening of the three air valve, and increasing the ventilation in the kiln;
(4) the ring can be calcined by hot and cold alternate method to make the ring fall off and reduce the feeding properly. long thick skin with greatly mobile kiln coal injection pipe, and appropriately reduce or even stop feeding material according to the severity of the burn, hot and cold alternating method.
abnormal phenomenon 3: kiln temperature is too high
possible reasons: (1) the feed quantity of kiln is small or the material is broken; (2) burning temperature is high; (3) the ventilation in kiln is too large; (4) the coal pipe is in the right place.
treatment method: (1) adjust feed quantity and check the reason of broken material; (2) strengthen fire operation, reduce the amount of feed; (3) reasonable balance of wind, coal and material; (4) adjust the location of coal pipe.
abnormal phenomenon 4: first cyclone outlet temperature rise
possible reasons: (1) raw feed volume is too small or broken; (2) the system air flow is too large; (3) incomplete combustion of pulverized coal.
treatment method: (1) adjust feed quantity and check the reason of broken material; (2) adjust system air volume; (3) raise fineness of pulverized coal, adjust system working condition.
anomaly 5: the temperature of a cyclone is suddenly raised
possible reasons: (1) blockage of cyclone at the upper stage; (2) breaking material; (3) thermocouple failure.
treatment method: (1) stop material, deal with jam; (2) find out reason and deal with; (3) change thermocouple.
abnormal phenomenon 6: decomposition furnace outlet temperature rise
possible reasons: (1) the amount of coal supplied by precalciner is too large; (2) raw material is reduced or broken; (3) a stage cyclone is blocked.
treatment methods: (1) adjust the amount of feed; (2) adjust the feed quantity, check the reasons for breaking; (3) stop material, deal with the blockage.
abnormal phenomenon 7: decomposition furnace outlet temperature drop
possible reasons: (1) lack of feed coal and excessive feed of kiln head; (2) collapse of a certain type of cyclone; (3) three air flow is insufficient; (4) three air flow is too large; (5) three air duct leakage.
processing method: (1) balance calciner and kiln head coal; (2) the cyclone can be kept stable for a small hour, the material is big, the material is reduced and the kiln is slow. (3) adjust the three air.
abnormal phenomena 8: negative pressure increase at the end of kiln
possible reasons: (1) the air volume in the kiln is too large; (2) the inner ring and the big ball in the kiln; (3) the feed capacity has increased greatly.
treatment method: (1) adjust the system air volume; (2) deal with the loop; (3) check feed.
abnormal phenomena 9: low negative pressure at the kiln end
possible reasons: (1) clogging of rising flue crust; (2) the air volume in kiln is too small; (3) serious leakage of kiln sealing device.
treatment method: (1) deal with crust; (2) adjust the system air volume, reduce the three air; (3) check the leakage.