MEASURES TO REDUCE THE TEMPERATURE OF CEMENT

1. Cause Analysis Of High Temperature

1.1 High Temperature Of Clinker Entering The Mill

The clinker produced in the rotary kiln of the company is 2000T/D, and the actual production needs 2800t / D, resulting in a short cooling time in the storage

It is almost used in production without staying, and the temperature of clinker is as high as 94 ℃.

1.2 High Specific Surface Area Of Finished Cement

The higher specific surface area control index of the finished cement will cause the grinding time of the material in the grinding to be too long, the heat generated will be too much, and the temperature of the cement out of the grinding will also increase.

1.3 Less Ventilation In The Mill

In order to pursue the qualified rate of specific surface area of cement unilaterally, the control method of small air volume is adopted, resulting in the phenomenon of over grinding of materials in the mill, and the temperature of cement out of the mill also increases.

1.4 Short Cement Storage Time

According to the 1D strength arrangement, the cement leaves the factory, which is equivalent to the time when the cement is stored in the storage only 1D. Sometimes it is less than 1D. It is almost added and lowered, and there is no cooling and cooling in the storage, which is almost equal to the temperature at the time of grinding. If the cement is arranged to leave the factory according to the 3D strength result, the cement can be stored in the storage for another 2 days, and the cement temperature can be reduced by 3-5 ℃.

2. Cooling Measures Adopted

2.1 Add Atomizing Water Spray Device In Coarse Grinding Bin

The atomizing water spray device is installed in the coarse grinding bin to cool the ventilation gas in the mill and quickly remove the grinding heat generated in the mill. The device has the function of compressed air injection to prevent the powder in the coarse grinding bin from blocking the atomizing nozzle. After the device was put into operation, the grinding temperature of p.0425 cement decreased about 4 ℃, and that of p-052.5 cement decreased about 2 ℃.

2.2 Add Water Spray Device To Powder Separator

Four middle 35nM circular spray nozzles are installed on the shell of the powder separator, on which a hole of middle 3mm is drilled every 250mm for water spraying. By reducing the shell temperature, increase the heat dissipation of cement in the powder concentrator. After the device was put into operation, the temperature of p-042.5 cement decreased by about 5 ℃and that of p.052.5 cement by about 3 ℃.

2.3 Reasonable Use Of Clinker Of The Plant And Purchased Clinker

The temperature of purchased clinker is about 10 ℃lower than that of local clinker. When the clinker reserve of the plant is insufficient, it is necessary to fully and reasonably dispatch and utilize the 20000 tons of clinker purchased each month, so as to make the clinker of the plant and the purchased clinker reasonably used together and minimize the temperature of the clinker entering the mill.

2.4 Properly Reduce The Specific Surface Area Of Finished Cement

Through many physical tests, the quality inspection department adjusted the control index of specific surface area of cement on the premise of ensuring the water sink strength:

The specific surface area of p-042.5 cement decreased from 340mpkg to 320m2kg; the specific surface area of p-052.5 cement decreased from 380mvhkg to 360m2kg.

2.5 Properly Increase The Ventilation In The Mill During Operation

After the cement specific surface area assessment index is reduced by 20 m / kg, the production department requires the mill operator to increase the ventilation in the mill, reduce the residence time of materials in the mill, prevent the over grinding of materials, and reduce the cement temperature out of the mill.

2.6 Water Spraying Device Is Used For Cement Grinding Cylinder

A water pipe with diameter of φ 100mm shall be installed directly above the cement grinding cylinder, and a hole with diameter of φ 5mm shall be drilled for water sprinkling every 150 mm. After the device is put into operation, the application effect is quite ideal: reduce the cement output of p.042.5 by about 7 ℃, reduce the cement output of p.052.5 by about 5 ℃:

2.7 Arrange Cement Delivery According To The Test Results Of 3d Cement Strength

Arrange the cement to leave the factory according to the test results of 3D cement strength, and control the cement inventory to ensure at least 5000T, otherwise it is strictly prohibited to leave the factory. When cement is delivered from the warehouse, two or more cement warehouses must be matched for discharging. It is strictly prohibited to discharge cement in a single warehouse. Through the monitoring of online temperature testing device, the cement temperature before delivery shall be less than 85 ℃