Large efficient condensation evaporator

The invention provides a large efficient condensation evaporator. The large efficient condensation evaporator comprises a shell, and multiple heat exchangers laminated in the shell, wherein nitrogen condensation sides and oxygen evaporation sides are arranged on the heat exchangers; the nitrogen condensation sides comprise nitrogen sealing heads, nitrogen guide pieces, nitrogen fin channels and nitrogen sealing bars; the oxygen evaporation sides comprise oxygen guide pieces, oxygen fin channels, oxygen middle fins, rectangular air rising pipes, rectangular reflow liquid bushings, liquid receiving plates and oxygen outlets; the liquid receiving plates are arranged between the upper and lower heat exchangers; the rectangular reflow hydraulic bushings are arranged on the liquid receiving plates; and rectangular air-liquid collecting ports are respectively formed in the upper parts of the heat exchangers. The large efficient condensation evaporator has the advantages of reasonable design, simple mechanism, convenience for use, efficient heat transfer and reliable operation.