Noise-eliminating displacement assembly and noise-eliminating energy-recycling system

The utility model discloses a noise-eliminating displacement assembly which comprises a Roots supercharger device, a Roots expansion machine device, a first guide pipe, a second guide pipe and a flexible membrane, wherein the first guide pipe extends out of a supercharger fluid inlet, and a fluid is supplied to the Roots supercharger device through the first guide pipe; the second guide pipe extends out of an expansion machine fluid outlet, and a fluid is guided by the second guide pipe to leave from the Roots expansion machine device; the first guide pipe is adjacent to the second guide pipe; a first open pore is defined by the first guide pipe while a second open pore is defined by the second guide pipe, and the first open pore and the second open pore are aligned approximately; the flexible membrane is arranged in the first and second open pores and between the first and second guide pipes; the second guide pipe and the first guide pipe are hermetically separated from each other by the flexible membrane; when the fluid flows in the first and second guide pipes, the flexible membrane deflects to eliminate noise generated by the fluid. The utility model also discloses a noise-eliminating energy-recycling system comprising a power source and the displacement assembly.