Operation method of ignition and heating of cement rotary kiln
Date：2019-09-27 15:41 Source：cementepcViews:
1. Preparation of cement rotary kiln
Upon completion of all preparations, the ignition site shall contact with the central control operator to prepare for ignition, and the central control operator shall inform relevant positions of the section (kiln tail, kiln middle and kiln head) to prepare for ignition through intercom.After receiving the ignition instruction, the operator will guide the wood pile with diesel torch through the bridge plate at the kiln head. After confirming that the wood pile is burning, the operator will quickly withdraw to the door of the cement rotary kiln, remove the bridge plate and close the door of the cement kiln.
2. Timing of coal injection
The wood pile was fully ablaze, the fire was in the middle of its ascent, and it began to spray coal.After coal injection, cement rotary kiln kiln head front not station people, miscellaneous personnel to clean out the cement rotary kiln table.Irrelevant personnel shall not look into the cement rotary kiln, but an operator shall stand on the surface of the cement rotary kiln and keep in contact with the central control with intercom at any time.The operator must wear a fire cap when observing the flame.After coal injection, no one is allowed to stand at the entrance of each floor at the end of the kiln and at the front of the monitoring hole. The operator should pay close attention to the temperature change at the end of the kiln to judge the combustion condition in the cement rotary kiln.After the flame stability, according to the kiln head fire camera use requirements, can inform the instrument workers, confirm the compressed air open, into the camera lens.At this time, the central control kiln operator can adjust and control the flame and temperature through the industrial television picture in the cement rotary kiln.The field operator on the kiln table can be evacuated back to the central control room.It is worth noting that the initial coal injection head is easy to appear positive pressure back fire, industrial camera is easy to damage, generally should not be opened early use.
3. Reasonable heating curve should be developed before each ignition feeding
Especially the initial production kiln.The heating curve is the heating system, which is generally formulated by the technician in the firing workshop and referred to by the central control room operator.Initial coal injection amount should be small, generally about 1.00-2.0t /h (take 2 500t/d as an example);If the fire back slightly, can increase the amount of coal.In the late period of wood combustion, pulverized coal combustion from strong to weak, at this time, should increase the amount of coal injection: after the formation of the flame, the requirements of rapid withdrawal of a small amount of coal, maintain the flame: confirm the kiln system all normal, can continue to add coal heating.
4. Maintain the flame and control the heating rate at the end of the cement rotary kiln
When the kiln is initially put into operation, the temperature at the end of the kiln of the cement rotary kiln heats up rapidly, often out of control, and sometimes rises to over 600 ℃ very quickly.Now reduce coal, the flame will be extinguished;Add coal, cement rotary kiln kiln end temperature rising speed is super fast, it is very adverse to drying refractory lining.If the lining of the newly built cement rotary kiln heats up too fast and the water inside the lining overflows too quickly, it will often cause the pouring lining to burst and endanger the long-term service life of the refractory lining.At present, many new dry cement rotary kilns have high ignition chimneys and great pumping force in the kilns. At this time, the wind speed in the kiln can be adjusted by opening the draft fan at the head of the cement rotary kiln, so that the temperature before the kiln is short and concentrated.
5. Determine the judgment basis of pulverized coal combustion
Whether the pulverized coal is burning or not can be generally judged by the color of the smoke. Black smoke is no combustion or incomplete combustion of pulverized coal. The whiter and cleaner the smoke is, the better the combustion condition of pulverized coal in the rotary kiln.Secondly, the trend of the temperature at the end of the cement rotary kiln can also be used as the basis to determine whether the coal injection is burning. The temperature continues to rise steadily and the combustion condition is good: the temperature drops rapidly, indicating that the coal is not burned or not completely burned.Of course, whether a flame is formed or not is also the most direct basis for judging combustion.