Surface waste heat recovery device of cement rotary kilnDate: 2019-07-22 Views:
Cement production industry belongs to an industry with high energy consumption. If no effective energy saving method is adopted and waste heat is fully utilized, the energy consumption will increase greatly.Therefore, in order to reduce the energy consumption of the cement plant, it is necessary to make full use of waste heat from the surface of the cement rotary kiln, collect waste heat with the help of waste heat recovery device, and supply it to the hot water for production and living in the factory or for heating in some areas.Therefore, this paper mainly discusses the matters needing attention, characteristics and specific application methods of the design of the surface radiation waste heat recovery device of cement rotary kiln, so as to provide reasonable reference opinions for cement production enterprises to save energy and reduce consumption and promote the smooth progress of cement production.
1. Relevant matters needing attention for design of waste heat recovery device
In the process of cement production, rotary kiln body is an important device for cement production.The surface temperature of the rotary kiln is about 250-300 ℃. Taking the kiln with a capacity of 5000t/d as an example, the radiation produced by the kiln can effectively meet the heat required for the life of the factory, and at the same time provide the heating supply needed for some office buildings.However, in the design of waste heat recovery device should pay attention to the following points, in order to effectively realize the role of reducing production efficiency.
(1) select the appropriate location of waste heat recovery device.
As the cylinder body of rotary kiln is relatively long, the temperature difference of each section is relatively large during calcining, and the influence factors of temperature should be taken into account when setting waste heat recovery device .
(2) set the structure of waste heat recovery device.
The structure of waste heat device should be designed reasonably to ensure that the installation of the device is simple and easy to maintain.Based on the characteristics of cement rotary kiln cylinder, it is more appropriate to adopt o-shaped support structure or c-shaped structure area.The design of such a structure can promote each cylinder are close to facilitate the work of thermal radiation.At the same time, in the cylinder temperature scanning work does not affect the case, convenient maintenance work.
(3) the water outlet temperature should be controlled within an appropriate range to ensure the normal operation of the rotary kiln body at the same time.
Because the waste heat recovery kiln body needs to ensure the actual effect of heat transfer, therefore, the distance between the surface of the rotary kiln body should not be too far apart.And the outlet temperature should be appropriate.
2. Characteristics of waste heat recovery device
A series of standard components, such as water pipe and channel steel, are components of waste heat recovery device.The heat-collecting surface of the waste heat recovery device belongs to the surface of the paint pipe coated with black and heat-resistant high temperature.Such a device can effectively ensure the effect of heat collection, even in harsh conditions such as cement production.Secondly, the waste heat recovery device is mainly composed of multiple recovery units, which are designed in a modular way and arranged flexibly according to the actual needs.The device is arranged according to the way of "c-shaped" 288° around the rotary kiln cylinder, and 72° openings are reserved. This way provides great convenience for detecting the surface temperature of the rotary kiln, and at the same time, it will not have a great impact on cement production in the process of waste heat recovery.
3. The conclusion
In the cement production process, it will generate a lot of energy, if not used effectively, it will cause a lot of energy consumption.The cooling process emits high-temperature exhaust gas, and the surface of the broken rotary kiln will also emit a large amount of thermal radiation to the environment, eventually causing heat loss.In the past, manufacturers usually used cooling fans to remove the energy of rotary kiln cylinder, but the heat is wasted.