Abstract: A multiple module heat exchanger having a serpentine path for one fluid to flow transversely through adjacent modules while a second fluid flows longitudinally therethrough. A guide pin carried by one module and a mating receptacle carried by a module adjacent thereto cooperate to permit relative longitudinal movement between modules while precluding relative transverse movement therebetween. The mating guide pin and receptacle are located at the central axis of adjacent modules whereby there may be a limited amount of pivotal movement between adjacent modules.

Abstract: The method of casting a plate type recuperative heat exchange envelope that encloses a hollow space therein in a single casting operation. A sand core with a heat sensitive binder therein defines the hollow space within the envelope. The sand core is supported by end extensions and lateral protuberances which rest on the sides of a sand mold to provide a space therebetween that is subsequently filled with molten metal to comprise an envelope casting. Lateral openings through the envelope casting produced by the lateral protuberances and end openings produced by the end extensions provide passageways for venting gases produced within the sand core during the casting operation, and after completion of the casting operation the same openings in the envelope assist in the removal of the sand core therefrom. The lateral openings are subsequently plugged while the end openings are maintained open to direct the flow of fluid therethrough.

Abstract: A Kraft pulping process by which spent pulping liquor is burned in a recovery furnace 12 to reduce inactive alkali sulfates therein to active alkali sulfides while producing molten smelt that when added to water forms green liquor and residual dregs bearing catalytic iron. The dregs are separated from the green liquor and divided into first and second portions. The first portion of the dregs is discarded while the second portion of dregs required to maintain a concentration of iron in the smelt at from 0.05% to 5% is recirculated back to the furnace to provide optimum catalytic reduction of alkali sulfates to alkali sulfides. A quantity of alkali metal compounds is added at 24 to the pulping liquor in line 10 to serve as a temperature depressor that, together with the co-addition of said dregs, lowers the temperature of the molten smelt in furnace 12 from approximately 800.degree. C. to a more favorable temperature of about 650.degree. C.

Abstract: A rotary regenerative heat exchange device has a rotor of heat absorbent element 19 that is exposed alternately to hot and cold fluid in order that heat from the hot fluid may be transferred to the cold fluid. The rotor is surrounded by a housing 22 including a sector plate 42 at opposite ends of the rotor that separates the hot from the cold fluid. The sector plate is forced to correspond to thermal distortion of the rotor to preclude fluid leakage therebetween. A unique fiber optic sensing device 58 utilizes a beam of infrared rays that detects excess clearance space between the rotor and the adjacent sector plate to actuate means that provides suitable corrective measures.

Abstract: A bag filter arrangement having a cleaning system that exhausts a reverse pulse of compressed air through the bags thereof to remove collected dust particles from the surface of the bags. The arrangement is directed to a special cooperation of interlocking elements that positively align the several elements thereof in order that maximum dust removal is effected.

Abstract: A bag filter apparatus that exhausts a blast of compressed air into the open ends of a series of filter bags to remove dust particles that have collected on the outer surface thereof. The compressed air is exhausted from nozzle means in a header pipe that is precluded from excessive distortion, while it may be quickly disassembled and accurately re-assembled to achieve optimum performance.

Abstract: An arrangement that utilizes agglomerating coal as a binder to bond coal fines and recycled char into an agglomerate mass that will have suitable retention time when introduced into a fluidized bed 14 for combustion. The simultaneous use of coal for a primary fuel and as a binder effects significant savings in the elimination of non-essential materials and processing steps.

Abstract: Rotary regenerative heat exchange apparatus including a cylindrical rotor of heat absorbent material that is alternately exposed to a hot and a cold fluid in order that heat absorbed from the hot fluid may be transferred to the cold fluid passing therethrough. The rotor is surrounded by a housing that includes a sector plate at opposite ends thereof to separate the hot from the cold fluids. As the rotor turns and is being subjected to a wide range of temperatures, it distorts into a dish shaped element. A mechanical toggle arrangement moved by a hydraulic actuator forces the sector plate into a configuration similar to that of the adjacent face of the rotor so as to preclude excessive leakage of fluid therebetween.

Abstract: Rotary regenerative heat exchange apparatus having a rotor of heat absorbent material that is alternately exposed to hot and cold fluids in order that heat absorbed from the hot fluid may be transferred to the cold fluid. The rotor is surrounded by a housing including sector plates at opposite ends of the rotor that are arranged to separate the hot from the cold fluids. Fail safe apparatus is provided to quickly release a sector plate from a position where it is held in close proximity to the rotor whereby a sudden variation of conditions will not permit mutual interference between relatively rotating parts.

Abstract: A cleaning arrangement for a bag filter that shakes the bags horizontally to effect removal of the dust particles that have collected on the surface thereof. A linear force electromagnetic motor is used to impart the horizontal movement to the bags whereby the frequency, amplitude and the duration of movement may be electronically controlled.

Abstract: A heat pipe heat exchanger in which heat is transferred from hot fluid in duct 12 to cold fluid in duct 14 by a continuous cycle of evaporation and condensation of a liquid contained in heat pipe 26. Should the heat pipe not function properly, the transfer of heat to that portion of the heat pipe lying in the duct for cold fluid will be reduced partially or completely. This reduction in temperature at the end of the heat pipe lying in the duct for the cold fluid is immediately sensed by a thermocouple 54 and indicated upon a gauge 56 which is adapted to identify a particular heat pipe. Repair or replacement of a faulty heat pipe will return each heat pipe to its maximum effectiveness.

Abstract: A bag filter assembly adapted to permit rapid removal, replacement and repair of the individual filter bags in the assembly. The filter bags are frictionally held in an operational position by a combination of interlocking parts that are securely held by spring biased detents. The spring biased detents of the several parts are designed to permit assembly and disassembly of the bag filter by a series of direct push-pull movements.

Abstract: A fluidized bed boiler feed system for the combustion of pulverized coal. Coal is first screened to separate large from small particles. Large particles of coal are fed directly to the top of the fluidized bed while fine particles are first mixed with recycled char, preheated, and then fed into the interior of the fluidized bed to promote char burnout and to avoid elutriation and carryover.

Abstract: A maintenance platform for a boiler-furnace that permits safe and ready access to its normally inaccessible upper parts and integral superheater. The maintenance platform is installed in the furnace, below the superheater on a horizontally movable support whereby said support may be selectively moved across said furnace or stored laterally adjacent thereto.

Abstract: Rotary regenerative heat exchange apparatus including a housing that surrounds a rotor of heat absorbent material. A pair of oppositely spaced sector plates intermediate the ends of the rotor and the rotor housing are subjected to a force biasing them to conform to thermal deformation of the rotor to preclude leakage of fluid therebetween. A mechanism is provided whereby the sector plates are quickly released from the biasing force to preclude interference between the rotor and the sector plates.

Abstract: Vibration of boiler tubes in a bank of parallel tubes of a multidrum boiler is prevented by means of directing a restraining tube in each bank of tubes obliquely between spaced drums. The oblique tube is welded to the parallel tubes at each point of contact to provide mutual support therefor. Boiling water is directed through the oblique tube as well as the parallel tubes so that circulation through the tubes is enhanced while tube vibration is prevented.

Abstract: Rotary regenerative heat exchange apparatus in which a rotor of heat absorbent material is alternately exposed to a heating fluid and to a fluid to be heated. The rotor is surrounded by a housing having a sector plate at opposite ends thereof adapted to separate the heating fluid from the fluid to be heated. The apparatus is provided with control means that intermittently drives a sector plate into a sealing relationship with the adjacent edge of the rotor after which a predetermined reference point on the rotor activates a sensor to move the sector plate away from the rotor to permit freedom of movement therebetween.

Abstract: A filter arrangement that imposes an electric charge of "like" polarity upon particulate matter carried by a gas stream and upon a porous support for a filter whereby the particulate matter is repelled from the filter support but caused to collect loosely on the leading edge of the adjacent filter to form a loose bed of increasing thickness that enhances the effectiveness of the filter. The filter and the support therefor are both comprised of temperature resistant ceramic materials while a metallic coating on the surface of said ceramic support distributes the charge evenly to all portions of the filter support.

Abstract: A reciprocable soot blower that is adapted to extend laterally through an outer wall to remove deposits of slag that collect on the walls of a pressurized furnace, gasifier or other reactor. The soot blower is telescopically mounted in a conduit attached to an outside wall of the furnace to permit its complete withdrawal from the furnace when not in use. A steam seal is adapted to be activated in the conduit when the soot blower is extended to increase pressure in the conduit to thus prevent entry of foreign material from said furnace into the space between the conduit and the soot blower.

Abstract: A fire detection system for rotary regenerative heat exchange apparatus having multiple detectors, each detector being mounted independently on an arcuately reciprocable scanning arm. The several arms are laterally adjustable by a system of opposed screws in an articulated yoke to permit the selective positioning of each arm independent from the other scanning arms of the system.