Discuss in which areas it is necessary to up-convert frequency in delayed coking

Distillation tower top air cooler, diesel transfer air cooler, heavy paraffin oil pump, feed oil pump

High-power, low-voltage motors that operate continuously can all be frequency-transformed. Specifically, all the side-line pumps except the gasoline pump are included, and all the pumps in the absorption and stabilization system except the liquid hydrocarbon pump are included.

In principle, electric power machinery such as pumps for which the selected head or flow rate turns out to be too high, as determined through calculations and practical operation, can all be subjected to variable frequency control. . . :lol

Theoretically, any circuit controlled by a control valve can be converted to variable frequency operation; the speed changes of the motor result in pressure drops at the control valve. However, considering specific circumstances, the following components can be considered for variable frequency conversion. First are circuits with significant load variations; second are motors with high power, generally those over 15KW can be considered; third is single-circuit control; fourth are low-voltage motors. High-voltage frequency converters are too expensive, and their quality is not very good either. For multi-loop control, frequency conversion can also be considered, but a control valve is needed as an auxiliary adjustment mechanism; in single-loop control, the control valve can be completely omitted. We have used it successfully for five years with no problems.

In principle, electric power machinery such as the furnace exhaust fans, blowers, air coolers of various devices, pumps for desulfurization and regeneration, cold coke water pumps, coke cutting water pumps, heavy paraffin oil pumps, injection pumps, and any other pumps for which it has been determined through calculations and actual operation that the selected head or flow rate is excessive, can all be subjected to variable frequency control

The first unit that truly requires up-conversion is the cold focus water pump, as it operates under variable conditions with a flow rate that varies significantly from the beginning to the end of the water supply process. I think the vast majority of devices have been installed. Next is the radial feed pump (high voltage of 6000V); its designed head is usually quite high, but in reality such a high head is not necessary, resulting in a lot of energy being wasted on the control valve assembly. Additionally, the pump experiences relatively large vibrations during operation. ~Of course, high-voltage frequency converters are expensive, but considering their actual performance, they are still worth the cost! Next is the furnace fan; variable frequency control can be used to regulate the air intake volume and adjust the temperature in the low-temperature section of the air preheater, thereby preventing dew point corrosion. Of course, it is also necessary to install a smoke extractor, as it allows for easy control of the negative pressure in the furnace chamber. For other similar devices such as diesel pumps, drill rig winches, screw pumps for transferring oil, sewage pumps, and feed pumps for stabilizer towers… we have all installed variable frequency drives.

The pump can operate with variable frequency within the range of 20%-80% of its design capacity.

Pumps in circuits where the selected head or flow rate turns out to be excessive based on calculations and actual operation, as well as those with significant load variations, are pumps that require frequent parameter adjustment. In short, it should be easy to operate, energy-efficient, and costs also need to be taken into account – a comprehensive consideration is necessary.

Feed pump, radiation pump, cold coke water pump, intermediate stage pump, wax oil pump, rich gas compressor, blower!

If the device is well-designed and operates at full capacity, with no margin for adjustment in its various components, then the role of variable frequency drives is not very significant; they can only help to compensate for some pressure drops.