Sluice for combustion furnaces as rotary kilns

An apparatus for removing burnt materials such as cement clinker from a furnace such as a rotary kiln or uncombusted residual materials and the like from a furnace such as a rotary kiln, said furnace having an ash pit defined by a shaft which communicates with an appropriate discharge end portion and a conduit communicating with the shaft for discharging said material from the furnace which comprises:

• a. a duct having a substantially rectangular cross-section connected to said shaft and having a cross-section approximately equal to that of the ash pit and attached to the lower end portion thereof, said duct being oriented in a generally slanted and downward direction relative to vertical and horizontal planes, said duct having an internal lining formed for relatively wear-resistant plates which define a sluice chamber therewithin;
• b. a first flap rotatably mounted to the upper end portion of the duct and having a first open position which exposes substantially the full cross-section of the duct to the ash pit communicable therewith, and a second closed position which substantially seals the upper end portion of the duct and defines an upper wall portion of a sluice chamber defined within said duct;
• c. a second flap rotatably mounted with respect to the lower end portion of a duct and having a first open position which exposes substantially the full cross-section of the lower end portion of the duct so as to permit discharge of material accumulated within a sluice chamber and a second closed position which substantially seals the lower end portion and defines the lower wall of said sluice chamber within said duct;
• d. water nozzles positioned in the side walls of said duct between said upper and lower flap and connected to a water supply means and capable of continuously introducing water into the sluice chamber at a minimum rate at least sufficient to contain dust in the sluice chamber and to maintain said nozzles in a relatively dust free condition at least when the lower flap is in a closed position and the upper flap is in an open position and material from the ash pit is permitted to enter the sluice chamber, said nozzles and water supply means further being capable of introducing water into said sluice chamber at a relatively increased rate sufficient to cool material accumulating therewithin at least when the upper and lower flaps are in closed positions;
• e. pneumatically operated actuating means connected to each flap, said actuating means being operatively connected by an electrical-pneumatic control system to selectively open and close said flaps so as to rotate the lower flap to its closed position and the upper flap to its open position so as to permit material discharged from the furnace to accumulate up to a predetermined level within the sluice chamber while said nozzles introduce water into said sluice chamber at a rate at least sufficient to contain dust therein and to maintain the nozzles in a relatively dust free condition, said pneumatic system and actuating means being capable of closing the upper flap while maintaining the lower flap in a closed position while said nozzles introduce water into said sluice chamber at said relatively increased rate to provide cooling of the material accumulated therein, said pneumatic system and actuating means further being capable of opening the lower flap to cause discharge of the material accumulated within the sluice chamber;
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• f. a transport bucket capable of being selectively positioned beneath the lower flap for receiving material discharged from the sluice chamber and means operatively associated with said transport bucket to delay opening of the lower flap for a predetermined time period corresponding to a full cycle of the sluicing operation and means for transporting said bucket from said sluice chamber to another location when it at least partially filled to a predetermined level.

A method for operating a sluice system for removing hot material such as cement clinker from a furnace such as a rotary kiln or uncombusted or slag material and the like from a furnace through an ash pit communicating with a discharge opening of the furnace and having a steel plate duct having a cross-section at least equal to the cross-section of the ash pit, said duct being connected to the ash pit and positioned in a downward, relatively steeply slanted position, an upper rotatably mounted flap having an open position exposing substantially the full cross-section of the duct to the ash pit and a closed position at least substantially sealing communication between the duct and the ash pit and defining the upper wall of a sluicing chamber within the duct, a lower rotatably mounted flap having an open position exposing substantially the full cross-section of the lower end portion of the duct and having a closed position at least substantially sealing the lower end portion of the sluicing chamber within said duct and defining the lower wall of said sluicing chamber, nozzle means mounted in the side wall of the duct between said upper and lower flaps and connected to a water supply means and adapted for introducing water into said sluicing chamber defined within said duct comprising:

• a. positioning a material receiving means in a material receiving position below the discharge end portion of the sluicing chamber;
• b. closing the lower flap and opening the upper flap for a time period sufficient to permit a predetermined amount of said material from the ash pit to enter the sluicing chamber while simultaneously introducing water through said nozzle means and into said sluicing chamber at least at a minimum level sufficient to contain dust and to maintain the nozzle means in a dust free condition;
• c. closing the upper flap and introducing water through said nozzle means at a rate greater than the rate of introduction of water utilized to contain the dust in the sluice chamber and sufficient to further cool the hot material in said sluicing chamber;
• d. discontinuing the introduction of cooling water at said greater rate;
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• e. opening the lower flap while simultaneously permitting the relatively cooled material to be discharged from the sluicing chamber into the material receiving means.