Discussion and practice of high temperature calcination of petroleum coke
As an important raw material of contemporary chemical industry, the high-temperature calcination process of petroleum coke has an important impact on the quality and yield of petroleum coke. In this paper, the high temperature calcination technology of petroleum coke is discussed in combination with its production significance. For the reference of enterprises.
Significance of production of petroleum coke by high-temperature calcination
Calcination of petroleum coke is one of the main processes in the production of aluminum anode. Its purpose is to remove volatiles from raw materials and improve the density, mechanical strength, electrical conductivity and chemical stability of raw materials. During the calcination process, the elemental composition and organizational structure of petroleum coke have changed, and the physical and chemical properties of raw materials have been significantly improved after calcination.
This special product property can meet the chemical industry more requirements, so that some industrial enterprises again use. In the process of calcination, the thoroughness of calcination degree and the pertinence of calcination process will affect the output and accuracy of petroleum coke. Therefore, it is of great significance to study high temperature calcination technology for petroleum coke.
Technical analysis of calcined petroleum coke at high temperature
Combining with the chemical trade of our country to calcine reachs the various requirements of the quality, safety, production rate and so on of petroleum coke product, the present common high temperature calcine ways of our country are: rotary kiln, coke oven, tank furnace, etc. The principle, characteristics, applicability and economic indicators of several calcination technologies are compared in order to provide reference for enterprise production.
(1) Rotary kiln calcining technology
1. Principle analysis: Rotary kiln technology combined with the special physical structure of rotary kiln can achieve effective heat treatment of solid petroleum coke. The principle of rotary kiln technology is to rely on the external temperature rise in the process of petroleum coke calcination and the chemical action inside the rotation speed up, so as to accelerate the combustion rate of petroleum coke and make petroleum coke produced by high-temperature calcination.
1) Preheating: by slowly rotating the cylinder and adding certain combustive materials to make the internal petroleum coke reach the ignition point and burn slowly;
2) Calcination: external acceleration of cylinder rotation, while increasing the temperature of calcination, the internal petroleum coking chemical reaction intensified;
3) Cooling: Condensation of petroleum coke after volatilization of water produces petroleum coke with high precision.
3, advantages and disadvantages and practical analysis: combined with the large-scale industrial production, rotary kiln has the characteristics of simple operation, large output, low cost, convenient maintenance, etc., can effectively operate for enterprises for 20 to 30 years, suitable for a variety of carbon petroleum coke use. At the same time, the rotary kiln itself uses the rotation and chemical reaction principle of internal combustion materials to save the cost of combustive materials. However, when the petroleum coke is rotating in the cylinder axis, the high temperature is easy to cause the wear and fall off of the refractory, resulting in unstable quality of the calcined products, among which the high-precision production is only about 10%.
Therefore, combined with the characteristics of rotary kiln, enterprises need to conduct targeted treatment of furnace building materials and processes during operation, so as to meet the requirements of improving industrial production efficiency, strengthening calcination intensity and enhancing product accuracy as far as possible.
(2) Coke oven calcination technology
1. Principle analysis: Coke oven calcination calcines the coke that has been specially treated through a high temperature calcination furnace made of brick blocks with high fire resistance, and the produced coke is ground and treated to form fine products required by the industry to produce coke. In this process, there are very strict requirements on the batching of raw coke and the temperature and time of calcination of coke.
2, advantages and disadvantages and practical analysis: compared with rotary kiln technology, coke oven has higher production and high precision characteristics. It chooses to deal with a wide range of ingredients, can achieve automatic control in use, can produce a high standard of finished coke for enterprises. At the same time, coke oven production is also faced with some construction problems, high requirements of coke oven construction, high accuracy of furnace temperature control, high maintenance cost will affect the penetration rate of coke oven production input.
However, for the development of petroleum coke calcination technology in the future, coke oven calcination can realize the role of energy saving and emission reduction, and can make certain contributions to environmental protection and comprehensive utilization of energy, coke oven calcination has a broad development prospect.
(3) tank calciner technology
1. Principle analysis: The main structures of canne-type calcination furnace include: feeding tank, fire passage, heat exchange chamber, feeding and discharging device, cooling water circulation device, etc. In the process of high temperature calcination, the petroleum coke added to the tank realizes the continuous reaction of the internal carbon material through the internal fixed material, so as to complete the high temperature calcination. The common calcination tank can be divided into downflow calcination and counterflow calcination according to the degree and direction of smoke discharge.
2, advantage and disadvantage analysis and practical analysis: canner type calcination furnace is widely used in our country, is the core industrial means of our country carbon industry, through the special treatment of petroleum coke can meet the heat fully, indirect heating requirements, and the interior can avoid the air contact, reduce oxygen loss rate, improve the output and quality of finished products. However, when adopting the canister calciner technology, there are many manual operation processes, which increases the safety risk. At the same time, the tank calciner itself has many hole requirements, which causes difficulties for maintenance.
In the future, enterprises can further study the canister calcination technology from the discharge quantity, fault hazard investigation and other aspects, so as to achieve the purpose of increasing the production of petroleum coke high temperature calcination.
To sum up, the high temperature of petroleum coke calcination has a great influence on the chemical industry and aluminum industry of our country. Enterprises can choose the appropriate high-temperature calcination technology according to their own industrial needs, and finally realize the cost reduction and efficiency increase of enterprises.