The utility model relates to a dry-type dedusting hydraulic system, which belongs to the field of control technology. According to the technical scheme, the dry-type dedusting hydraulic system comprises a coal gas releasing valve cylinder, a coal gas recycling valve cylinder, a releasing valve cylinder control device, a recycling valve cylinder control device and an emergency control device. The emergency control device comprises an energy accumulator, a one-way throttle valve, three hydraulic control one-way valves and three cartridge valves, wherein the liquid inlet of the first hydraulic control one-way valve is connected with a pressure oil pipe while the liquid outlet is connected with the energy accumulator through the one-way throttle valve and is connected with the upper cavities of the coal gas releasing valve cylinder and the coal gas recycling valve cylinder through the first cartridge valve; the oil inlets of the second cartridge valve and the second hydraulic control one-way valve are connected with the lower cavity of the coal gas recycling valve cylinder while the liquid outlets are connected with an oil recycling pipe; and the oil inlets of the third cartridge valve and the third hydraulic control one-way valve are connected with the lower cavity of the coal gas recycling valve cylinder while the liquid outlets are connected with the oil recycling pipe. When the flue gas in a blast furnace is in the explosion limit range, the dry-type dedusting hydraulic system can quickly ignite the coal gas so as to diffuse the coal gas, so that the leakage explosion in an electrostatic deduster is prevented. Therefore, the smooth production of the blast furnace is ensured.