The present invention relates to a system for drying coal using reheat steam, and more particularly, to an apparatus for enhancing drying efficiency by adjusting reheat steam to be injected to coal input and transferred onto a transfer device at predetermined pressure in a multi-stage dryer drying the coal by using reheat steam and in the apparatus for adjusting steam pressure in a system for drying coal using reheat steam, a steam supply pipe supplying the reheat steam generated by a reheater is connected to one side of each of the first steam chamber, the second steam chamber, the third steam chamber, and the fourth steam chamber and a first steam distribution perforated plate with a plurality of steam injection holes is coupled to and installed in the inner upper part of each of the first steam chamber, the second steam chamber, the third steam chamber, and the fourth steam chamber to inject the reheat steam at uniform pressure through the first steam injection holes.

The present invention relates to a coal supply device for reducing dust of coal input for dry and supplying dispersing and supplying the coal in a system for drying coal using reheat steam, and more particularly, to a device to minimize dust when the coal is supplied to a multi-stage dryer from a coal constant feeder through a pulverizer in a multi-stage dryer for drying coal using reheat steam and disperse and supply the coal to a transfer device and a coal drying system in which coal which is primarily dried in the first coal dryer is inputted into the second coal dryer and thus is secondarily dried, includes a coal constant feeder supplying a predetermined amount of coal onto the upward surface of the first transfer plate; and a dust reducer constituted by an inlet pipe coupled to an outlet of the coal constant feeder by a bearing, a worm wheel coupled onto the outer periphery of the inlet pipe, a worm gear-coupled with the worm wheel and rotating with rotary force transferred from a motor, a curved pipe of which the top is coupled to the inlet pipe, and an outlet pipe coupled to the end of the curved pipe, wherein the dust reducer which rotates at the predetermined velocity reduces the velocity of the coal supplied by the coal constant feeder to minimize generation of dust from the coal input onto the upward surface of the first transfer plate.