Waste heat circulation system for direct air cooling tower

The invention discloses a waste heat circulation system for a direct air cooling tower. The waste heat circulation system is composed of a desalting water tank, a filter screen, a high-pressure pump, a regulating valve and an air cooling unit, wherein the desalting water tank, the filter screen, the high-pressure pump, the regulating valve and the air cooling unit are sequentially connected through pipelines. The air cooling unit is composed of a direct air cooling tower and a draught fan located on the lower portion of the interior of the air cooling unit, wherein the direct air cooling tower is formed by obliquely building fin pipes. Spray nozzles are further arranged above the draught fan. Air flows into the air cooling unit above through the spray nozzles. Multiple sets of air suction pipelines are arranged on the exterior of the direct air cooling tower in parallel and are fixed above the interval spaces of the adjacent fin pipes in the axial direction of the fin pipes correspondingly. Air suction openings are further formed in the lower portions of the air suction pipelines. Waste heat air between the fin pipes enters the air suction pipelines through the air suction openings. The output ends of the air suction pipelines are in butt joint with air feeder air feed pipelines of a boiler. Hot air at an outlet of a direct air cooling condenser is used for air used for boiler combustion, recycling of hot air at an outlet of the direct air cooling tower is achieved, the utilization rate of fuel is increased, thermal pollution is reduced, and the effects of energy conservation and emission reduction are achieved.