PRESSURE BOOST METHOD AND DEVICE THEREFOR WITH USE OF AIR BUBBLE PUMP

PURPOSE:To enhance the capacity of each of a plurality of pumps in a group connected in series and make it possible to take out vapor, by separating vapor from a discharged gas-liquid two phase stream from each evaporating pipe while liquid is fed into a downcomer pipe and by then feeding the liquid into a next stage evaporating pipe. CONSTITUTION:A plurality of air bubble pumps U1-U4 in a group are laid, each being composed of an condensing chamber 4 incorporating a cooling means 3, an evaporating pipe 3, a downcomer pipe 2 and a communication means 8 for communicating the lower end of the downcomer pipe 2 with an evaporating pipe 1 in the next stage air bubble pump. With this arrangement, a working fluid system 102 introduced into the air bubble pump U1 is heat-exchanged with a heat source fluid system 101 to be turned into a boiled two phase stream. Thereafter, the stream is subjected to gas-liquid separation, and vapor is liquefied by a cooling pipe and then is fed into the downcomer pipe 2 together with the other fluid. The working fluid in the downcomer pipe 2 is introduced into the evaporating pipe 1 in the next stage pump through the communication means 8. With the repetition of these steps the working liquid is successively boosted up, and is discharged from the final stage pump. With this arrangement the boost-up capacity of each air bubble pump may be increased to make it possible to greatly boost up the generated pressure in total.