Sludge treatment method for drying sludge by using coal grinding machine and using sludge for electricity generation

The invention discloses a sludge treatment method for drying sludge by using a coal grinding machine and using the sludge for electricity generation. The method comprises the following steps of: 1) directly introducing wet sludge with the moisture content of 70 to 90 percent into the coal grinding machine, wherein the ratio of the wet sludge is 2 to 10 percent of a fuel coal; 2) performing heat exchange between the waste heat of a utility boiler flue gas and air to generate primary air blown into the coal grinding machine, mixing the sludge with the fuel coal in the coal grinding machine, and performing grinding while drying; and 3) spraying the coal powder containing the dried sludge into the utility boiler for burning and generating electricity. The coal grinding machine which is also used as sludge drying equipment is characterized in that a hot air introduction device is a rotary type hot air nozzle ring, a powder reflux device is a through-type flow-guiding powder reflux cone, and a separating device is a rotary separator with a first separate stationary blade. The sludge treatment method makes full use of the original process of an electric power plant, makes full use of the waste heat of the flue gas and the heat value of the sludge, and acquires no additional hot resource or device for drying the sludge, and has the advantages of investment saving, low operation cost, no secondary pollution and the like.