A new type of air cooler with pulse dust cleaning device is developed for the heat exchange of cement rotary kiln flue gas (hereinafter referred to as new air cooler, which is used to distinguish traditional air cooler). Under the premise that the heat exchange efficiency is guaranteed, the inner wall ash accumulation of the heat exchanger tube can be removed and the overall area and height of the air cooler can be reduced without increasing the caliber of the heat exchange tube.

1. structural features

The new air cooler consists of dust cleaning system (gas storage tank, blow pipe, nozzle, pulse valve, Dan Xiangfa), cooling pipe and axial fan. It has the following characteristics:

1) the heat transfer steel pipe is arranged in a row arrangement, each pulse valve corresponds to a spray tube, each spray pipe is corresponding to a row of heat exchange tubes, and a nozzle on a spray pipe is corresponding to a heat exchange pipe opening.

2) the flue gas passes through the interior of the heat exchange tube, and the inner wall of the heat exchange tube is gradually accumulated ash.

3) the gas storage tank and the blowing pipe are connected by a one-way valve, and only the high-pressure jet flow is allowed to pass one-way, and the pulse valve is not damaged by the reverse passing of the high temperature smoke stream.

2.Operation and maintenance

To ensure the normal operation of the air cooler at the rotary kiln end, we should pay attention to the following points:

1) the normal operation of the dust cleaning program

Check the working state of the pulse jet device, according to the dust concentration, set the time gathering 2mm-thick dust inside the pipe wall as the dust pulse cleaning cycle. In actual operation, if the resistance of air cooler is increased, the ash cleaning period can be reduced accordingly. Once the blowing device fails, it needs to be dealt with in time to prevent the failure of the pulse cleaning in the cooling pipe.

2) Check the inner seal of the air cooler

Air tightness leakage of welding seam or manhole will cause water vapor into the air cooler. The corrosive components in the flue gas of the kiln will aggravate the fouling of the dust when it meets the water vapor, leading to the weakening of the effect of cleaning the cooling pipe.

3) the normal operation of axial fan

The axial fan provides a forced heat exchange between the ambient air and the cooling pipe, which ensures the performance of the air cooler. Therefore, the reliability of the axial fan influences the cooling and cooling effect of the air cooler. In order to ensure the continuous and reliable operation of axial fans, proper maintenance procedures should be carried out.

In addition, during the operation of air cooler, it is necessary to check and record the temperature data regularly. Compared with the normal temperature, the system error is found in time, and the alarm is given and handled in a timely manner.

3.Injection tube layout of new air cooler

Under the condition of more and more shortage of water resources, the use of air coolers to cool high temperature smoke is the direction of the development of flue gas cooling. The successful application of the above cases proves the feasibility of the application of the new air cooler at the cement rotary kiln end in the cement production. This will greatly expand the range of the use of air coolers, especially in the field of flue gas cooling with high viscosity and high concentration dust.