What does the size of coke depend on? ? ?
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This post was last edited by Desert Poplar on 2010-9-8 at 22:18. Our coke formation time is 72 hours, with a standard temperature of 1150 degrees (the same in both measurements); recently, the size of the coke pieces has been particularly large! The company’s management said it’s because the temperature is too low, which causes coking! I would like to ask, what does the size of coke have to do with? Is the size of the raw coke lumps large? Thank you all for your guidance
During the coking process of coal in the coking chamber of a coke oven, due to temperature gradients and shrinkage stresses, the entire coke cake is divided into pieces of varying sizes by numerous vertical and horizontal cracks. After being pushed out of the coke oven, the coke cake undergoes processes such as natural falling and mutual collision, including quenching, transportation, and screening; larger pieces of coke break apart along the original large cracks to form smaller pieces. This fragmentation process is inevitable in the current chamber coke-making process. On the other hand, since the coke naturally breaks along its original cracks into smaller pieces and is graded, this helps to maintain the coke pieces at a relatively constant size, which is necessary and advantageous for users. However, the coke transported from coking plants continues to crack under external forces until it is used, due to the presence of some visible or internal cracks in the coke as well as its relatively poor structural strength. Both coke producers and users prefer as little crushing of this type as possible.
The situation described by the poster is likely not charring; operating at a lower temperature for a longer coking time will increase the size of the coke particles as well as their resistance to crushing
1. It is related to the coal blending ratio; adding an appropriate amount of lean coal can improve speed, but the wear resistance is poor. Bituminous coal often yields broken coke. 2. The heating speed is fast and the standard temperature is high, intensifying the shrinkage reaction. The coke cake has many cracks and is fragmented. 3. The heating rate is slow, the standard temperature is low, and the shrinkage reaction is slowed down, resulting in larger coke particles. When the standard temperature is low at extended working hours, larger lumps are normal. However, no matter how long the cycle lasts, the temperature at the center of the coke must reach 950–1050°C. Pushing coke generates high coke-pushing current and black smoke. At the same time, the char forms black spots on its surface and fails to develop a charred wall. Last edited by 26722672 on 2008-11-26 15:05]
When the coking time is long, the standard temperature is low and the coking rate is slow, allowing the colloids to penetrate thoroughly. As a result, the time required for the coke to cool down is longer, which makes it difficult for cracks to develop. Consequently, the coke does not tend to crack into large pieces when it is fully matured; therefore, larger piece sizes are normal under conditions of prolonged coking time.
By testing the volatile matter content of coke, if it is less than 1.6%, then it is not green coke.
The size of coke lumps is influenced by several factors: firstly, the proportion of low-calority coal in the blend is a bit high. Secondly, the standard temperature is too low; you should measure the temperature in the space above the furnace as well as the temperature at the center of the coke cakes. The temperature at the center of the coke cakes must be maintained around 850 degrees.
A large particle size does not necessarily mean it is raw coke; test the coke, and also check the specifications and temperature of the coal fed into the furnace
Large particle size is closely related to the formation of coke. The surface of the coke appears quite rough
“The coking time is 72 hours, and the standard temperature is 1150 (the same for both measurements). Will it still be green coke? ? ? Your leader is an amateur, isn’t he? . Don’t go overboard, or you won’t be able to push it out later. . With the same coal blending ratio, it is normal for the coking time to be longer, the coking rate to be slower, and the size of the coke to be larger.
Actually, whether the coke is mature or not can be told just by looking at its surface! It has a silver-gray surface, and the sound it makes when it hits the ground is similar to that of metal hitting the ground. In the coking plants of steel mills, coke undergoes a granulation process during transport via belts; the key factor is the size of the coke particles before they enter the blast furnace, with a particle size range of 40–60 being ideal!