Does ethylene cracking require a boiler? What size boiler is needed for 1 million tons of cracking?
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This post was last edited by Fish in the Desert on 2021-11-24 17:24 Does ethylene cracking require a boiler? What size boiler is needed for 100 tons of cracking?
In order to meet the steam needs for start-up, we previously built 300,000 tons of ethylene, equipped with two 20-ton boilers, as well as desulfurization and denitrification, a lot of equipment, and a separate "boiler area".
A 20-ton boiler is too small. I think some projects are 400-ton boilers.
According to the reverse operation method, if the three machines and five towers are started first, it is estimated that the three machines of the 1 million tons ethylene plant will require at least 300-400t/h steam at low load.
Cracking gas compressor, ethylene refrigerant compressor, propylene refrigerant compressor quench oil tower, quench water tower, ethylene distillation tower, propylene distillation tower, depentanizer tower (not sure? )
Propylene machine, ethylene machine, cracked gas compressor, quenching water tower, alkali washing tower, deethanizer tower, ethylene distillation tower, propylene distillation tower
Because our device does not have a quenching oil tower, the three machines and five towers are just our summed up experience. Each device may be different, but the same approach leads to the same goal. At least these reverse engines need to be opened first. Other devices may have other devices that need to be opened first. The latter is pre-cooling and feeding. After the cracking furnace drum starts to produce steam and is connected to the pipe network, everything will be fine.
If the cracks begin, can the boiler be stopped?
The three machines (propylene machine, ethylene machine, cracked gas compressor) are driven by steam turbines, and the normal operation of the ethylene unit also requires continuous use of power steam.
This boiler uses the waste heat of the cracking furnace to produce steam, so it is always on (the steam produced by the cracking furnace can fully satisfy the operation of the cracking gas compressor. The excess steam is reduced to 4.0Mpa through the temperature reduction and pressure reducer). Therefore, after the cracking furnace drum (boiler) produces steam, there is no need to supplement a lot of external steam. Based on the scale of our 800,000-ton ethylene plant, normal operation only requires external supplementation of 20-40t high-pressure steam (4.0Mpa).