Solid-liquid separation device

A solid-liquid separation device that performs dehydration or deoiling from an object to be treated that is a mixture of water and a solid, a mixture of oil and a solid, or a mixture of water, oil, and a solid, as the object to be treated, using a substance A capable of dissolving water and oil, the solid-liquid separation device comprising:

• a substance B that is circulated while generating phase change in a closed system;
• a compressor that compresses the substance B;
• a first heat exchanger that exchanges heat of condensation of the substance B and heat of evaporation of the substance A;
• a second heat exchanger that exchanges heat of evaporation of the substance B and heat of condensation of the substance A;
• a treatment tank in which the substance A is mixed with the object to be treated, the substance A having been evaporated while separated from the water or the oil in the first heat exchanger, and condensed in the second heat exchanger, wherein
• the first heat exchanger is installed in a lower portion than the treatment tank in a vertical direction, and
• a connection port of the first heat exchanger and a lower portion of the treatment tank are connected with a flow path;
• and
• a third heat exchanger installed downstream of the treatment tank and upstream of the first heat exchanger in a flow path system of the substance A, and which switches a flow path of the substance B flowing into the heat exchanger 1 in an upper stream of the heat exchanger 1 to exchange heat between the substance B and the substance A, wherein
• the third heat exchanger is installed in a lower portion than the treatment tank in a vertical direction.