PURPOSE: To improve profitability by using exhaust heat of liquid-utilizing equipment to cool and heat a vessel in the process of sucking liquid into a vessel by discharging heat to the outside so as to reduce the pressure in the vessel, and then sending the liquid out by raising the pressure in the vessel due to the heat supply from the external.

CONSTITUTION: A side 6, a bottom 7 and a top 8 of a vessel 1 having an work space 2 in which a displacement element 3 is located to be vibricated, conveyed and driven by a drive means 5 are respectively formed to double wall shapes and separated from each other to be provided with individual heat exchange function. An inlet 10 and an outlet 11 communicating respectively with a low pressure portion and a high pressure portion of an absorption device are formed in the lower portion of the vessel 1, and check valves 12 and 13 are disposed for the inlet 10 and the outlet 11, respectively. Further, low-temperature cooling water is passed through the vessel bottom 7 to over-cool the vessel 1, the check valve 12 is opened by reducing the pressure in the vessel 1 so as to make the liquid flow into the vessel 1, a high-temperature liquid is passed through the cover 8 so as to heat the vessel 1, and the check valve 13 is opened by raising the pressure in the vessel 1 so as to discharge the liquid out.