Abstract: A continuous grain drying and conditioning apparatus of a type including a burner and blower, or a multiplicity of burners and blowers, surrounded by a plenum chamber, air pervious grain holding walls positioned outwardly with respect to the plenum chamber is characerized by having a plenum divider which is selectively adjustable in position to divide the grain holding walls into a heating section and a cooling section. Grain turning apparatus is disposed in the grain column for separating the grain mass into two separate divisions and then turning the cooler-wetter grain inwardly as it moves downwardly and turning the hotter-dryer grain outwardly as it moves downwardly in the grain column. Grain is constantly removed from the bottom of the apparatus at a rate governed by the average temperature of the air exiting the grain at a point adjacent the position of the plenum divider and a point closer to the input of the grain.

Abstract: A scrap preheating system of the type employing a conveyor upon which the scrap is placed, an elongate burner hood surrounding the conveyor and burners within the hood which direct flames upon the scrap. The side walls of the burner hood include an elongate exhaust chamber and side wall ports between the exhaust chamber and the interior of the hood. An exhaust fan induces a negative pressure under the hood through the exhaust chambers which pulls the unburned hydrocarbons from under the hood through the side wall ports into the exhaust chamber. Additionally, air is drawn upwardly between the conveyor and side walls of the hood and through the side wall ports into the exhaust chambers wherein combustion is completed and pollution reduced. The length of hood and burner array exceeds the length of scrap material on the conveyor. The conveyor is periodically jogged during the preheating cycle to slightly advance and mix the scrap and only those burners positioned above the scrap are operated as it advances.

Abstract: In the calcination of petroleum coke or the like in a rotary kiln, utilizing controlled air supply intermediate the ends of the kiln to burn removed volatiles and thereby generate all or nearly all of the heat required, highly effective control procedure includes establishing and repeatedly re-establishing target values for temperatures of exit gas and discharging product respectively at opposite ends of the kiln, such target temperatures representing conditions of desired position of the calcining zone and desired physical character of the calcined product which is achieved by proper maximum temperature in said zone. The procedure further includes adjusting one or more of the variables of combustion air supply, RPM of the kiln, and green coke feed rate so as to keep the end temperatures at target value.

Abstract: An apparatus is disclosed in which a raw material feed delivery pipe is connected to the periphery of a vertical conduit that receives gases from a rotary kiln and conducts such gases upwardly to a location where the gases are divided between a pair of cyclone gas-solids-separator heat exchangers comprising a first stage of raw material preheating. An axially movable and rotatable sleeve is mounted over the discharge end of the pipe, and the sleeve is provided with a terminal nozzle portion curved to discharge raw material at an obtuse included angle to the axis of the delivery pipe. A method is disclosed by which the sleeve is moved along the pipe and rotated relative to the pipe, to change the nozzle discharge location and deflection angle relative to the rising gas stream, until an equal temperature drop of gases in both heat exchangers is achieved and balanced loading thereof is thereby indicated.

Abstract: In vertical continuous furnace calcining of lime, dolomite, magnesite, or the like, part of the air which is introduced at the lower end of the furnace chamber is drawn off in the area of the cooling zone within the chamber and is then reintroduced in encompassing relation into the material column in the firing zone within the furnace chamber and which is located immediately above the cooling zone, the remainder of the air flowing up through the column of material being treated in the chamber. Cleaning of the withdrawn cooling air and addition of fresh air are provided for.

Abstract: A method and an apparatus for heating a granular aggregate for mixture with asphalt by means of a flue gas being chemically inert to the aggregate. The aggregate is moved intermittently within the gas under control of the stationary periods of driven screw conveyors. The apparatus has several heating sections, each section having a conveyor, a thermostat with a sensing device at the end of the section, and possibly also an oil burner, the thermostat being connected to the driving means of the conveyor.

Abstract: A calcining method and apparatus are provided wherein material to be treated is fed into the top of the furnace and the finished material discharges from the bottom of the furnace and cooling and combustion air enters under forced draft through the bottom of the furnace and flows upwardly through the column of material. A part of the fuel supply is delivered to the region between an upper preheating zone in the furnace and a subjacent combustion or firing zone and the balance of fuel required for firing is introduced into the combustion zone about its periphery. Provision is also made for bypassing part of the cooling air from a lower cooling zone to the combustion zone, with intermediate cleaning of the bypassed air.