Multi-stage natural gas excess pressure power generation system with inter-band heat

Abstract

The utility model provides a multi-stage natural gas excess pressure power generation system with inter-band heat, and belongs to the technical field of natural gas excess pressure utilization. According to the technical scheme, a multi-stage high-rotating-speed centripetal expansion machine is arranged, a centripetal turbine is directly connected with an efficient magnetic suspension generator, and electric energy output by the generator enters a frequency converter to be rectified and then is connected to a grid. The rotating speed of each stage of turbine is adjusted by monitoring the outlet pressure, so that the outlet pressure meets the requirement. And meanwhile, natural gas at each stage of outlet flows into the heat exchanger to exchange heat with normal-temperature water and flows into the next stage after the room temperature is recovered. According to the utility model, the pressure drop of each stage of turbine is small, the pressure can be adjusted only by the rotating speed, and energy waste caused by valve pressure adjustment is avoided; and the temperature drop caused by the small pressure drop is very small, so that the heat energy loss caused by the traditional forced heating is avoided. In addition, the expansion machine adopts a high-speed centripetal turbine, so that the efficiency is higher, and the size is smaller; the turbine is directly connected with the generator, so that energy loss caused by a speed reducer is avoided, and a lubricating system is not needed; the generator is a magnetic suspension generator, and generating efficiency is high.