| 摘要 |
A fractional distillation process is provided in which at least part of the heat required at the reboiler is provided by indirect heat exchange with an absorbent solution which is absorbing a gaseous working fluid at a first pressure; and in which the absorbent solution is regenerated for recycle to additional absorption by lowering its pressure to a second pressure no more than 70% of the first pressure, supplying heat to it to resorb gaseous working fluid at the second pressure, and restoring its pressure to approximately the first pressure; and in which the gaseous working fluid at first pressure is provided by condensing the gaseous working fluid at second pressure, increasing its pressure to approximately the first pressure, and supplying heat to boil it, and -in which at least one of the heat supplies necessary for boiling the working fluid and for regenerating the absorbent solution is provided by indirect heat exchange from the heat rejected at the reflex condenser. This process provides the ability to recover and recycle between 40% and 100% of the energy from the reflux condenser to the reboiler. The equipment required is simple, reliable, and economical - it consists essentially of heat exchangers and-pumps. The amount of additional electrical energy required is negligible in comparison to the amount of energy saved. The process can efficiently recover and recycle even low temperature heat, e.g. 70.degree.C or less. It can also easily handle recovery in situations where there is a large temperature differential between reboiler and reflux condenser. It can handle part load operation even more efficiently than full load, and is easy to start up and shut down. It is not susceptible to surge, overload, imbalance, or other problems which affect compressor driven heat pump energy recycle. With optional additional heat exchangers, it can recover and recycle at least 70% of the theoretical amount of heat it is possible to recover. With provision for a low temperature heat input such as solar or geothermal, it can completely eliminate the need for any higher temperature heat input. |
