Device for compressing and drying gas and a method applied thereby

A device for compressing and drying gas, comprising:

• a compressor device and a dryer that uses a drying agent for drying gas connected to the compressor;
• the compressor device comprising two or more compressor elements each having an inlet and an outlet, said inlets and outlets being connected together in series to form a first low-pressure stage and one or more subsequent high-pressure stages which are each connected with their inlet connected to the outlet of a previous compressor element via a pressure pipe;
• an outlet pipe in which an aftercooler is provided;
• said dryer having a drying section and a regeneration section, said drying section being filled with a drying agent for drying a gas that is guided there through, and an inlet which is connected to said outlet pipe of the compressor device and an outlet defining an exit arranged to supply compressed and dried gas:
• said regeneration section arranged to enable moist drying agent to be dried by a regeneration gas which is guided there through via an inlet, an outlet, and a regeneration pipe connected to the inlet;
• a gas-gas heat exchanger arranged to heat at least part of the regeneration gas, said gas-gas heat exchanger comprising a primary part which is disposed in the regeneration pipe and a secondary part that is fed by a pressure side of the compressor element;
• and
• said secondary part of said gas-gas heat exchanger being disposed in the pressure pipe extending between the low-pressure stage and the subsequent high-pressure stage.