Heating furnace flue gas circulation oxygen distribution combustion system and automatic control method thereof

The invention provides a heating furnace flue gas circulation oxygen distribution combustion system and an automatic control method. The automatic control method comprises a hearth negative pressure control step and a furnace top flue gas oxygen content control step. When the negative pressure of the hearth is higher than the control range, the side drawing baffle is enlarged, when the negative pressure of the hearth is lower than the control range, the side drawing baffle is reduced, and stable control over the negative pressure of the hearth can be achieved. Whether combustion is sufficient or not is determined by the oxygen content of flue gas at the furnace top, when the oxygen content of the flue gas is lower than a control range, insufficient combustion and reduction of heat efficiency can be caused, at the moment, a primary air door is opened to enable more combustion-supporting gas to enter a hearth to assist combustion, and when the oxygen content of the flue gas is higher than the control range, the