Abstract: When burning black liquor obtained during cellulose pulp manufacture it is desirable to maintain a constant atomizing pressure. Mere throttling of the liquor supply in order to adjust the combustion to actual heat demand will alter the spray pattern. A pressurized gaseous fluid is injected into the liquor supply conduit, and the amount of this gaseous fluid is governed in response to the actual heat demand. A monitoring device senses the pressure in the supply conduit downstream of the throttle valve, and adjusts the position of the latter in response to the activity caused by the gaseous fluid, so the resulting pressure is maintained at the desired level.

Abstract: Air governing means at a refuse burning furnace may include a sleeve, which is axially reciprocable with respect to an air passage port in the furnace wall; in order to produce a high air velocity, the air is forced through a narrow, annular clearance between the perimeter of the inward end of the sleeve, and the passage port, the outward end of the sleeve being normally closed; to accommodate for axial mis-alignment at the outward end, the sleeve is adapted to cooperate with a tubular member projecting from the back wall of a plenum chamber supplying the passage port with air; the tubular member is provided with a head displaceable in a plane perpendicular to the longitudinal axis of the tubular member, and further having a tapering front end to facilitate re-introduction into the sleeve, when the latter, in order to perform a scraping function, has performed a stroke exceeding normal governing movement.

Abstract: A waste liquor recovery furnace includes a lower combustion chamber and an upper final combustion chamber, separated by a restricted gas passage. The furnace has a basically cylindrical configuration, being defined by a tube membrane shell, and the lower combustion chamber is formed by tubes from said shell being bent, doubly inwards, defining a discharge opening for the liquid combustion residue. A screen of tubes in the final combustion chamber is arranged to direct the gases towards the shell, being substantially solid in the center of the chamber, directly above the discharge opening.

Abstract: Waste liquor obtained when pulping wood can be advantageously burned and used for raising steam, while simultaneously chemicals are reclaimed. Certain waste liquors have a noted tendency to cause deposits in valves and piping, which therefore must be intermittently washed by a neutral fluid. This means an interruption of the supply of fuel to the burner, and even if a furnace usually is provided with several burners the interruption causes a disturbance of the steam production, beside necessitating a considerable amount of labor.The invention proposes a means for supplying liquid fuel and washing fluid simultaneously to each burner by two parallel conduits in such a manner that a simple switch-over will result in the (occasional past) supply conduit and the major part of the burner will be washed, while liquid fuel is supplied through a conduit having recently been washed.

Abstract: Air admittance ports in the wall of a refuse burning furnace are provided with reciprocable sleeve members which in the first hand govern the air flow, but also may be used to scrape the ports free of deposits. These sleeves are interconnected in groups so they can be manipulated simultaneously for cleaning purposes, but nevertheless may be adjusted individually as well as group-wise for flow governing purposes.