Abstract: There is disclosed a process and apparatus for the recovery of heat from exhaust or waste gases having a temperature of from about 500.degree. to about 2500.degree. F. generated in a process operation cycling between an operational mode and in idling mode utilizing an intermediate heat transfer fluid to recover heat and to use all or a portion of such recovered heat, inter alia, in such process operation.

Abstract: Process and apparatus for the gaseous direct reduction of iron ores wherein at least a portion of the spent reducing gas effluent from a reduction reactor is upgraded and thereafter heated and recycled to said reactor forming a reducing gas loop and make-up reducing gas is added to said loop. The hot products of combustion, i.e., flue gases, in the reformer are used to heat the recycled gas (and optionally the quenched make-up gas) while maintaining independent control of the operating conditions of the reformer and gas heater to give improved thermal efficiency and fuel savings. The reformer has a stand-by stack through which the reformer flue gas is directed when the gas heater is shut down (to permit independent continuous operation of the reformer).

Abstract: An apparatus for the manufacture of steel by direct reduction of iron ore dust comprises a single reactor vessel and a tubular reduction dust extending into the vessel to a point closely adjacent to the bottom of the vessel. The reactor vessel is provided with a source of reducing gas containing a monoxide and a predominant amount of H.sub.2. Heating mechanisms for the reduction dust, the iron ore dust, the source of reducing gas and the vessel are provided. The apparatus also includes a mechanism for the recycling of heat and the components of the waste gases of the reactor vessel.

Abstract: Device for controlling the particulate emission from coal-fired boilers including a cyclone type primary separator between the boiler and the stack and a bag filter coupled in side stream relation to the cyclone separator such as to shunt and departiculatize up to about 20% of the gas stream entering the cyclone. The shunted gas is drawn from below the tube sheet of the cyclone separator, filtered through the bags and returned to the stack. Means are provided to control the temperature of the shunted gas within defined limits corresponding to the acid dew point of the gas and the thermal degradation temperature of the filter media.

Abstract: The invention relates to an apparatus and a declogging process for filtration installation for dust-laden gases presenting reducing properties, consisting in taking dust-free gas at the outlet of the filtration installation, oxidizing this gas and using the gaseous mixture resulting from this oxidization to declog the filtering element(s) of said installation.

Abstract: A recuperator which includes vertically extending outer tubes and respective inner tubes within the outer tubes. Hot waste gases flow around the outside of the outer tubes. Air to be preheated flows through the inner tubes and annular passages between tubes. The outer tubes are formed of relatively short length sections of ceramic joined end-to-end. The lowermost sections rest on solid base blocks which support the weight of the outer tubes.

Abstract: Installation includes a throttle assembly built in the blast-furnace outlet pipe and at least two gas turbines with blast furnace gas heaters also built in the outlet pipe and being parallel with the throttle assembly. Each of the gas turbines having a control diaphragm and a stop diaphragm is provided with a separate drive for turning thereof. The installation is also furnished with an isodromic regulator, for the gas pressure under the shaft top of the blast furnace, electrically connected to the separate drives of the throttles, being a part of a throttle unit and by means of a logic control unit being connected to separate drives of the control diaphragms of the gas turbines. The regulator preselects a sequence of operation of the above drives, when in the process of gas pressure control under the shaft top in the super-capacity blast furnace, to open in the first-turn the control diaphragms of the gas turbines and then to open the throttles which are a part of the throttle assembly.

Abstract: The invention relates to an installation for melting pig-iron comprising a cupola furnace, a combustion chamber burning the waste gases leaving this cupola furnace. This installation comprises furthermore a heat exchanger between the flue gases leaving this combustion chamber and a thermodynamic fluid driving at least one rotary machine coupled to at least one electric generator, a superheating furnace for the pig-iron in the liquid state disposed between the cupola furnace and a casting station.

Abstract: A purifier for handling the high temperature effluent from a blister copper furnace, which includes solid particles in the range from 600 microns, or greater, down to a few microns, which contains oxidizable material, and which is at a high temperature, in the range of 2100.degree. to 2400.degree. F. The effluent from the blister furnace goes first to a settling chamber where the very large particles are caused to settle out by reducing the velocity of the effluent gas. The effluent then goes to a precooler tower which is an adiabatic humidifier, where the temperature is reduced to the neighborhood of 1200.degree. F. by injecting an air-driven water atomizer spray. The effluent then goes to an oxidation tower where the combustibles are oxidized, at lower than flame temperature, by injecting air and recycled gas. The effluent then goes to a conditioning tower which is a second adiabatic humidifier to further cool the gases to the neighborhood of 450.degree. F.

Abstract: Use of a shaft kiln in continuous smelting and refining of cement copper is made possible with a mix preheater, a refined gas preheater, an air preheater, an air mix feeder and forehearths for cement oxidation and reduction, and wherein oxidation is achieved by injecting oxidant gases and reduction by injecting preheated petroleum gas, subsequent to having placed a layer of charcoal on the smelt.

Abstract: A method of producing metallic iron pellets in a generally vertical furnace in which a gravitational flow of particulate material is reduced in a reducing zone by a countercurrent flow of a reducing gas containing a reductant, the spent reducing gas is removed and cooled and a portion is introduced as a cooling gas in a cooling zone near the bottom of the furnace while a second portion is employed as a fuel to heat a catalyst through which a gaseous hydrocarbon and steam are passed to form a reducing gas mixture for introduction into the furnace, and a portion of the cooling gas is upgraded in reducing potential and introduced to the reducing zone as reducing gas. Apparatus is also provided for carrying out the method.

Abstract: A high efficiency aluminum scrap melting system is provided in which a portion of the hot combustion gases employed to melt the aluminum in a hearth is recycled through scrap-receiving preheat compartments to preheat scrap and volatilize contaminants as the scrap is fed to the hearth, the remainder of the hot combustion gases leaving the hearth as hot exhaust gases being optionally employed through a recuperator to preheat air which is fed to a combustion burner system used to burn hydrocarbon fuel and provide heat for the overall system. Energy available in the contaminants also supplements the energy supply to the system.

Abstract: An improved cupola furnace waste gas recuperative system and method for collecting waste furnace gases, cleaning them for the purpose of safely burning same either in a recuperator-heat exchanger for preheating incoming furnace blast air or for other heating purposes. The improvement consists of a method and means to control the pressure inside of the gas take-off chamber of an open, top charged, cupola furnace for the purposes of preventing gases from escaping through the charging hopper, preventing the indraft of excessive amounts of air, preventing explosive combustion and flashback of the waste gas and maintaining cleaning efficiency at any gas flow rate. Means include the controlled recirculation of a variable portion of the waste gas through part of the gas cleaning system and control of the furnace top gas pressure as a function of the incoming cupola furnace blast air.

Abstract: Apparatus is disclosed for attachment adjacent an open end of a rotary furnace, having a first effluent furnace gas exhaust duct projecting into the furnace and a dust collecting hood adjacent the furnace opening. A pressurized air duct plenum having a plurality of air jet holes directs a curtain of air across the furnace open end, and a receiving air duct plenum having a plurality of openings collects the air curtain for exhausting via a filter system. The hot effluent furnace gas is passed through a gas to gas heat exchanger and to the aforementioned filter system.