Introduction to the next-generation petroleum calcined coke cooler

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This post was last edited by liuquan1100 on 2017-9-24 08:06. Calcined coke is a black or dark gray, hard solid petroleum product with a metallic luster; it is porous and consists of carbon particles in granular, columnar, or needle-shaped forms, formed from tiny graphite crystals. The components of the calcined coke are hydrocarbons, containing 90-97% carbon and 1.5-8% hydrogen; it also contains nitrogen, chlorine, sulfur, and heavy metal compounds. The main production process for calcined coke is: raw material transportation → screening and crushing → calcination → cooling → finished product transportation. The raw materials are preheated in a rotary kiln to temperatures of 1250–1350°C; once their physicochemical properties meet the required standards, they can be discharged. Such high temperatures are certainly beyond the capacity of conveying equipment, so it is necessary to cool the calcined coke. Since the finished calcined coke is required to have a moisture content of less than 0.3%, it is necessary to ensure that the entire production process takes place under dry conditions. To achieve sufficient cooling as well as drying throughout the entire process, the cooling of calcined coke is quite important in relation to the whole process. In the existing technology, the calcined coke enters the cooling cylinder through a discharge chute at the exit of the rotary kiln; through the combined action of direct water mist spraying inside the cylinder and cooling water spraying from outside the cylinder, the temperature of the calcined coke is reduced from 1000°C to around 100°C. The cooling cylinder has a single-cylinder structure; inside it, at the feeding level, there is a water chamber. Nozzles are also installed on the walls of this water chamber, and cooling water is sprayed onto the cylinder body through these nozzles to cool the material. The cooling water then flows to the bottom of the water chamber and is discharged through an outlet. The main problem with this cooling method is that the direct spraying of water mist inside the cylinder has an impact on the moisture content of the calcined coke product, thereby affecting the quality of the product ； Secondly, when calcined coke comes into direct contact with cooling at high temperatures around 1000°C, it can explode and undergo granulation, which also affects the quality of the finished calcined coke ； Third, the direct injection of cooling water vaporizes at high temperatures, generating large amounts of dust-laden smoke that causes severe environmental pollution ； Fourth, direct spraying of cooling water not only wastes water resources but also prevents heat recovery, resulting in a waste of resources. Through dozens of field tests and computer simulations, our company has invented and improved the roller cooler for calcined coke. This device prevents direct contact between cooling water and calcined coke, thereby ensuring that the quality of the calcined coke remains unaffected during the cooling process. It also helps to avoid the generation of smoke and dust, reducing environmental pollution and enabling clean production. Additionally, it allows the heat from the calcined coke to be recovered through the cooling water, thus achieving energy savings and reduced consumption. The main advantages of the product are as follows: 1. The heat exchange cylinder has a large diameter, preventing coking ； 2. Various arrangements of heat exchange surfaces result in a high heat exchange coefficient for the cylinder, ensuring excellent heat exchange performance ； 3. High cooling capacity, up to 30t/h ； 4. A unique layout of the cooling water circuits to ensure the highest possible cooling efficiency of the cooling water ； 5. adopts variable-frequency control for low consumption and energy savings ； 6. Robust active and passive safety measures ensure operational safety. The same equipment can also be used for cooling materials such as spodumene, manganese slag, and magnesium slag; the design of the cooling cylinder structure must take into account the specific physical properties of these materials. Our company has now developed a variety of cylinder structures that can meet the cooling requirements of more than 10 different types of materials. The equipment has a simple installation layout, and can be used for the renovation of existing production lines or to meet the process requirements of new production lines. For more details, please send a message within the platform. Taking our company’s project to handle the cooling of spodumene feedstock for lithium carbonate production at a rate of 20,000 tons per year as an example, the feed temperature is: 1000℃ ； Discharge temperature: 150℃ ； Output: P=30t/h Cooling water inlet temperature: 25℃ ； Cooling water outlet temperature: 80℃ ； The specific heat capacity of the material is C = 1.0 kJ/(kg·K). The total amount of heat released by the material per day is: Q1 = C × P × ΔT × 24 = 1.0 × 30 × (1000 – 150) × 24 = 6.12 × 105 kJ. The total amount of heat released per year (assuming 250 days of operation) is: Q = Q1 × 250 = 1.52 × 108 kJ. The heat released by the hot material is absorbed by the cooling water, which is then reused in the circulating water system for heating purposes. Converting this to standard coal (with the specific heat capacity of standard coal being C_coal = 2.94 × 104 kJ/kg), we get: Q_coal = Q / C_coal = 1.52 × 108 ÷ 2.94 × 104 ≈ 5100 tons. At a price of 400 yuan per ton for standard coal, this amounts to approximately 2 million yuan in cost savings per year.