Integrated drying process and device for dry granulated slag and sludge

An apparatus for molten slaq cooling, granulation and sludge drying, comprising:

• a) A molten slag cooling treatment device having a cylinder structure, comprising:
• a propulsion mechanism provided on an inner wall thereof, a molten slag feeding hopper provided at an inlet thereof, and a slag discharge mechanism provided at an outlet thereof;
• wherein the molten slag cooling treatment device is provided with a first driving device configured to drive it to rotate;
• b) A plurality of steel balls, and a steel ball transporting device coupled to the inlet of the molten slag cooling treatment device;
• c) A high temperature steel ball chute, one end of which is coupled to the outlet of the molten slag cooling treatment device;
• and
• d) A sludge drying device having a cylinder structure, comprising:
• a propulsion mechanism provided on an inner wall thereof, a sludge transporting device provided at an inlet thereof, and a dry sludge discharge device provided at an outlet thereof, wherein the sludge drying device is provided with a second driving device configured to drive it to rotate;
• wherein the inlet of the sludge drying device is coupled to the other end of the high temperature steel ball chute.

A method for molten slag cooling, granulation and sludge drying, comprising steps of:

• 1) Mixing high temperature molten slag and steel balls at a weight ratio of 1:50-100 in a molten slag cooling treatment device, wherein the high temperature molten slag and steel balls are fully and evenly mixed and heat exchanged by tumbling the high temperature molten slag and steel balls, wherein the steel balls absorb heat from the high temperature molten slag, while the high temperature molten slag is gradually cooled and crushed by the steel balls to form granular slag having a particle diameter of ≤150 mm and a temperature of lower than 400° C.;
• wherein the steel balls having absorbed heat have a temperature of 200-400° C.;
• 2) Discharging the granular slag through a slag discharge mechanism, and discharging the steel balls having absorbed heat into a high temperature steel ball chute;
• 3) Transporting the steel balls having absorbed heat to a sludge drying device through the high temperature steel ball chute to mix with sludge infused into the sludge drying device, wherein the sludge drying device is driven by a driving device to rotate so that the sludge and steel balls in the sludge drying device tumble, and fully and evenly mix and exchange heat, whereby the sludge is dried by the steel balls having absorbed heat;
• wherein the steel balls and dried sludge are separated when a moisture content of the sludge reaches a set value;
• wherein the dried sludge is discharged through a dry sludge discharge device, and the cooled steel balls are discharged through an outlet;
• wherein a mass ratio of the steel balls to the infused sludge is 2-10:1.