The utility model discloses a low-grade heat
recovery system for an oil
plant, which is characterized in that a conditioning
tower is sequentially provided with a feeding section, a heating layer, a
drying layer and a discharging layer from top to bottom, a
cold side preheating air outlet of an air-air
heat exchanger of the conditioning
tower is connected with an air inlet of the
drying layer of the conditioning
tower, and an air outlet of the
drying layer of the conditioning tower is connected with an inlet of a
cyclone separator of the conditioning tower; an air outlet of the
cyclone separator is connected with a hot side air inlet of the conditioning tower air-air
heat exchanger, a hot side air outlet of the conditioning tower air-air
heat exchanger is connected with an air inlet of the conditioning tower air-water heat exchanger, and an exhaust port of the conditioning tower air-water heat exchanger is communicated with the
atmosphere; a cold-side hot water outlet of the conditioning tower air-water heat exchanger is connected with a cold-side water tank, an outlet of the cold-side water tank is connected with an
evaporator inlet of a
heat pump through a cold-side circulating water pump, and an
evaporator outlet of the
heat pump is connected with a cold-side hot water inlet of the conditioning tower air-water heat exchanger. According to the
system, steam consumption in the
oil processing process can be reduced,
water vapor in low-grade hot air is recycled, and consumption of circulating cooling water is reduced.