Abstract: A fluidized bed steam generating system in which a duct is disposed between a furnace outlet and a separator inlet. The duct is formed by first and second wall panels which are comprised of a plurality of parallel tubes extending perpendicular to the direction of the flow of the combustion gases. The tubes comprising the wall panels are bent and welded to a fin extending from corresponding portions of adjacent tubes to form a gas tight structure. The ends of the tubes are connected in fluid flow communication with first and second headers which enables cooling fluid to flow through the tubes for recovering heat from the combustion gases as they flow from the furnace into the separator.

Abstract: A support lug casting for supporting a ferritic tube from an adjacent tube comprising male and female lugs formed on a ring shaped member and engaged around but not welded to each tube. The male lug of one tube engages into the female lug of an adjacent tube. The lugs and rings are made of austenitic material which resist corrosion and heat and which avoids the problem of welding dissimilar materials to each other since no welded connection is established between the austenitic casting and the ferritic tube. The casting is axially fixed on the tube by one or more ferritic stops or weld areas which are at one or both axial ends of each casting.

Abstract: A fluidized bed combustion method in which a recycle heat exchanger is located adjacent the furnace of the combustion system. A mixture of flue gases and entrained particulate materials from a fluidized bed in the furnace are separated and the flue gases are passed to a heat recovery section and the separated particulate material are passed back to the furnace. The walls of the furnace are formed by water tubes, and refractory metal material is placed adjacent the walls to control the heat absorption by the water passing through the tubes. The amount of refractory is selected in accordance with the desired operating temperature of the furnace.

Abstract: A pipe wall for hot reaction chambers comprises a plurality of pipes which together define a side to be heat loaded, and a plurality of holding elements arranged on the heat-loaded side for holding a temperature resistant coating. The pipes on the heat-loaded side together forming a substantially flat surface.

Abstract: A highly efficient boiler is made up of a housing containing upper and lower left and right water manifolds. Tubes connect the left manifolds and other tubes the right manifolds. The tubes are bent toward one another to form a plurality of superposed chambers through which combustion gases must successively flow, from front to back in one chamber and from back to front within the next. Baffles may be provided in each chamber to cause the gas to traverse a sinuous path from left to right and right to left within each chamber. Adjustment of the baffles can be effected during operation to keep the combustion gas exit pressure or temperature or flow rate constant notwithstanding changes in the liquid flow rate through the tubes or the rate of combustion of fuel in the lowermost chamber.

Abstract: A once-through stem generator includes a vertical gas flue having a total given height, a bottom, a lower part having a height equal to less than 70% of the total given height, an upper part, and fossil fuel burners disposed on the lower part. The lower and upper parts are formed of gas-tight tube walls with tubes. The tubes of the lower part rise obliquely, while the tubes of the upper part are vertical. The lower part has a lower end limited by the bottom, and the upper part has an upper end limited a partition of the vertical gas flue, by a cross-sectional restriction of the tube walls, or by a lower edge of a heating surface within the vertical gas flue.

Abstract: An economical, efficient, compact furnace is provided with horizontal radiant furnace tubes that extend along all the walls of the furnace for uniform heat distribution and load. The furnace is particularly useful in oil refineries and petrochemical plants. The furnace also has a special pattern of burners for safer, more effective heat transfer.

Abstract: A fluid flow circuit for a boiler having a combustion chamber and an exhaust passage. In one embodiment there is provided at least one upflow evaporative generating bank module in the exhaust passage and at least one downflow evaporative generating bank module in the exhaust passage, positioned downstream of the upflow module. One or more upper downcomers are connected to a steam drum and supply water to the lower header of the upflow module and to the upper header of the downflow module. If needed, the convection pass wall enclosures can also be fed by the upper downcomers to their upper inlet headers. One or more lower downcomers may be connected to each lower header of the downflow module (and to the lower outlet headers of the convection pass wall enclosures) for supplying the water to a plurality of furnace circuits which extend along the combustion chamber in the boiler. The opposite end of each furnace circuit is connected to one or more risers which, in turn, are connected to the steam drum.

Abstract: A wall (100) serves to separate two rooms (200,300) at different temperatures and has a plurality of essentially parallel tubular sections (11) which conduct a fluid medium, said sections being enclosed between two plate-like parts (2,3) and connected in a heat-conducting manner to at least one of the said parts. The two plate-like parts (2,3) are rigidly interconnected along an interface (50) essentially parallel to the two principal directions of the wall (100). The interface (50) is arranged so as to lie outside the external contour of the tubular sections 11). The plate-like part (3) containing the tubular sections faces the room (300) at the higher temperature.

Abstract: Device for the protection of boiler screens, in particular for garbage incinerators, and manufacturing process for this device. Device for protection of screens used for heat-recovery boilers, composed of vertical tubes 1, 14 joined together using welded ribs (17) installed between fireproof bricks and fitted with means for fastening them, these tubes being equipped with vertical auxiliary fastening ribs 2, 11; 3, 13 forming an angle of between 30.degree. and 60.degree. with the plane of the ribs 17, and made discontinuous at intervals on the vertical sections of the tubes. A first series of bricks in fastened on the upper portion of the auxiliary ribs. A second series of bricks 6, 18, alternating with the bricks of the first series, has a general dovetail shape and is fixed in position between recesses 7, 8 in the bricks of the first series. Process for the manufacture of this device.

Abstract: The hot-gas cooling plant has a gas outlet line releasably connected between the radiant cooler and the convection cooler. The gas outlet line is curved to extend from an upper region of the radiant cooler to the top end of the convection cooler. Flange connections are used to connect the gas outlet line to the pressure vessels of the coolers. Cooling tubes are also provided within the gas outlet line for cooling the flow of gas therethrough.

Abstract: A forced-circulation steam generator with a combustion chamber (1) that has a cone (2), whereby the combustion chamber is demarcated by piping walls with at least partly slanting pipes, the cone is composed of piping walls (9, 10, 11, and 12) with upright pipes, and the pipes in the combustion chamber are separated from the pipes in the cone by headers. The two series of pipes are separated such that the medium flowing through the pipes in the combustion chamber has the same enthalpy.

Abstract: In order to create an economic two-stage heat exchanger system which is capable of cooling cracked gas from short-term splitting furnaces, which is capable of flexible operation utilizing changeable charging stock, the two stages of the heat exchanger are integrated in one device, in order to avoid the necessity of delivering the cracked gas to a second stage via long, hot pipelines. In addition, the system has the capability of switching the heat exchanger plant over to a single-stage operation.

Abstract: A system for protecting a heat-recovery boiler screen, in particular for waste incineration furnaces, said screen being formed by vertical tubes (1, 2) interconnected by welded fixing fins (3, 4, 5) disposed in cavities in refractory bricks (7) and provided with hooking means for refractory bricks. The screen includes windows (6) going through the fixing fins, each brick is provided with at least one hooking lug (8) whose axis is at an angle to the horizontal such that each brick is held suspended by its own weight in one or more windows of the corresponding screen, and the gaps remaining between the bricks, their hooking lugs, and the screen are filled with a refractory cement (9).

Abstract: An apparatus and process for control rod assembly and construction for a nuclear reactor is disclosed wherein the control rod is of cruciform configuration having a plurality of and preferably four flat planar members. Each planar member is made up with an assembly of square cross sectioned tubular members. Each square cross sectioned tubular member includes a defined cylindrical center and a constant thickness surrounding tubular metallic shell to provide the contained neutron absorbing materials in a cylindrically shaped pressure vessel. The constant thickness surrounding tubular shell constituting the cylindrical shaped pressure vessel has four corner sections added to generate a modified square exterior profile. These added four corner sections comprise an addition to the tubular side wall thickness of the shell. Appropriate chamfers and rounding are provided to the square profile to impart both stress relief and convenient points for automated welding between side-by-side square sections.

Abstract: A continuous flow steam generator includes a vertical gas flue to which burners for fossil fuel are to be attached. The flue has a tube wall and a lower end with a bottom. The tube wall includes vertically disposed tubes with inlet and outlet ends and long sides being welded together in a gas-tight manner. The bottom includes other tubes having inlet and outlet ends and being welded together in a gas-tight manner. The tubes of the tube wall include tubes of a first tube group and tubes of a second tube group. The tubes of the first tube group are hydraulically connected to the other tubes of the bottom and have an outlet header connected to the tubes of the first tube group. The tubes of the second tube group have an inlet header and an outlet header connected to the tubes of the second tube group.

Abstract: A panel 1, 1A, adapted for the flow of coolant, therethrough, comprising coolant flow tubing having a coolant inlet aperture 11C at an inlet end of the coolant flow tubing and a coolant outlet aperture 12A at an outlet end of the coolant flow tubing, characterized in that the coolant flow tubing comprising a plurality of elongate tube lengths 2, 2A, 2B formed from hollow rectangular section material, the tube lengths 2, 2A, 2B being disposed in parallel relationship, either stacked one on top of the other or side-by-side, with adjacent external faces of adjacent top and bottom walls 3, 4 of adjacent tube lengths 2, 2A, 2B abutting one another, with the end of each tube length 2, 2A, 2B closed off, and with coolant flow apertures 11, 11A, 11B, 12, 12A, 12B communicating between adjacent tube lengths 2, 2A, 2B adjacent the ends thereof such that, in use, coolant flows in at one end of each tube length, along the tube length, and out at the other end of each tube length, to and through successive tube lengths of

Abstract: A locking system is provided for preferably locating ceramic tiles in furnace throats in which locking member engages in a recess in the rear surface of the tiles the other end being attached to part of the throat the head of the locking member and shaping of the recess permitting angling of the locking member in relation to the tile. This permits greater fiexibility in mounting the tiles in the throat.

Abstract: A rotary combustor has a wall formed from water cooled pipes that are secured together by welded perforated strips. The strips comprise cylindrical shaped metallic rods and the perforations are provided either by forming apertures through the cylindrical shaped metallic rods, or by slots formed between segments by spacing segments of cylindrical shaped rods along the pipes, or by gaps formed between welds that are provided at spaced intervals along the pipes and rods. A method of fabricating a rotary combustor wall is also provided.

Abstract: A device is provided for direct cooling of thick essentially horizontal wall members which are charged with different temperatures and possibly different pressures on their upper and lower sides, such as for cooling a heat exchanger tube sheet. Cooling of the wall member or component from the "cold side" is afford by closed end bores formed in the wall member which bores are open on the "cold side" and closed on the "hot side". Each closed end bore has a tube projecting from the "cold side" of the wall member and extending into the bore with its end within the bore located adjacent the closed end of the bore. The diameter of the tube is smaller than the diameter of the bore so that flow through the tube into the bore can reverse direction at the closed end and flow through the space between the tube and the bore.

Abstract: A furnace for a once-through steam generator comprising a lower section of inclined tubes and upper section of vertical tubes and a support system and tube arrangement at a transition zone intermediate the sections.

Abstract: A waste disposal system for the combustion of waste materials which includes a combustor having an inlet end and an outlet end with a furnace enclosing the outlet end. A step extends out from the back wall of the furnace which is spaced from and below the combustor outlet end. The step is hollow on the inside to form a plenum chamber to receive air and has an upper surface which defines a plurality of openings into the furnace whereby air injected through the openings deflects airborne ash and combustible solids from the outlet end of the combustor up into the furnace.

Abstract: A rotary combustor which includes a plurality of water cooled tubes secured together directly to each other to form a cylindrical barrel defining a combustion chamber therein. Every other length of tube is bent outwardly at spaced locations along its length to form a plurality of openings in the barrel to allow combustion air into the combustion chamber. Means including a smaller ring header and a larger ring header are provided at each end of the barrel to interconnect the tubes to permit the circulation of water therethrough.

Abstract: A multi-pipe once-through boiler having at least one row of a plurality of circumferentially arranged pipes on which a plurality of fins are arranged in such a manner that the fins are in contact with the flow of the combustion gas in a substantially parallel maner. Elements are provided for increasing the heat transfer effect, such as slits in the fins, or an inclined arrangement of the fins, or pipes without fins at the region near to the inlet of the combustion gas passageway, are provided. Furthermore, a heat insulating member for decreasing operational noise as well as a cleaner device for blow-cleaning the combustion gas passageway are provided.

Abstract: An arrangement for and a method of gasifying finely divided, particularly solid fuel under increased pressure with a multi-pipe wall having a plurality of pipes arranged to be supplied with a cooling medium, the multi-pipe wall limiting a gas-collecting chamber and also limiting a plurality of recesses which form combustion chambers, wherein each of the recesses having a plurality of parameters including a depth, a width and an angle of inclination of a peripheral wall and being such that at least one of the parameters is changeable

Abstract: A thermally turbulent combustion system for combusting solid fuel which includes a generally cylindrical, longitudinally extending stationary combustion chamber formed by a plurality of interconnected circumferential cooling pipes and fuel transport means provided adjacent the bottom of the chamber along the length thereof. A water cooled door may be provided at the inlet end of the chamber. The width of the chamber is greater than the width of the fuel path. A plurality of headers are connected to the pipes to supply and discharge cooling fluid thereto and therefrom. In one embodiment, the combustion chamber has a symmetrical cross-sectional configuration and the transport means is positioned centrally along the length of the bottom thereof. In another embodiment of the system, the chamber has an asymmetrical cross-sectional configuration and the transport means is positioned adjacent one side along the length of the bottom of the chamber.

Abstract: A cooler for gases generated from coal by gasification under pressure has a pressurized vessel (1) that accommodates an insert (5) with a polygonal cross-section made out of pipes (6) that are welded together gas-tight in conjunction with webs (7). The pipes in the insert are bent vertically in to create a roof (11) and parallel one another sector by sector with webs of uniform width. The pipes that abut at an angle at the edges of the sectors are united in pairs by forged crosstail butts (13). The crosstail butts are aligned along a straight line and completely occupy the spaces between the sectors.

Abstract: Vertical tubes joined to each other by means of welded coupling fins and forming boiler baffles for refuse incinerators are placed between refractory bricks and provided with vertical auxiliary anchoring fins which make an angle of 30.degree. to 60.degree. with the plane of the coupling fins and are interrupted at intervals over vertical sections of the tubes. One portion of the bricks is provided with vertical recesses corresponding to the auxiliary fins over a fraction of their height from the bottom and the other portion of the bricks is provided with vertical recesses up to their full height. The bricks of the first portion are anchored to the top portion of the auxiliary fins and the bricks of the other portion are engaged on these fins above a brick of the first portion.

Abstract: A heat exchanger for gases under high pressure comprises a pressure vessel, a pluraity of heat exchanger trains arranged in the pressure vessel so that gas flows through the heat exchanger trains, the heat exchanger trains being formed as substantially identical structural units, the heat exchanger trains being connected with one another with a gas deflection therebetween and being connected with the pressure vessel so that they are releasable from and separately removable from the pressure vessel, elements for gas deflection between the heat exchanger trains, and elements for releasably and separately connecting the heat exchange trains to the pressure vessel.

Abstract: A process for operating a furnace boiler with a firebox having a cooled wall and at least one blowpipe to direct flame into the firebox, and heat exchangers connected to the firebox through which the flue gases flow, consisting of the steps of extracting heat from the flue gases essentially only by the heat exchangers and cooling the wall of the firebox only to the extent that, at maximum burner output, the temperature on the inner side of the wall does not exceed approximately 600.degree. C. and, when the burner output is reduced to about 1/10 of maximum output, the temperature does not fall below approximately 180.degree. C.

Abstract: A burner throat is defined by a cage of tubes and is lined by fitting refractory tiles. A plurality of retaining means each having two joined parts, the outer part abutting the tubes and the inner part exerting an abutting force radially inwards on the tiles to retain them in position. In use the abutting force on the tiles can be varied to suit the design characteristics and environment, by varying the exposed length of a pin which threadedly mates in a complementary bore in each of the two parts. To further secure the tiles, a dowel is provided to mate in complementary bores formed in an adjacent side of abutting tiles.

Abstract: The fossil-fuel fired vapor generator has a vertical flue formed of vertical tubes and a funnel at the bottom end which is formed by helically extending tubes. In addition, the helically extending tubes are in communication with the vertically extending flue tubes via bifurcation elements in order to convey the working medium upwardly into the flue tubes. The flue may be of rectangular cross-section with the funnel of similar shape or the flue may be of at least a pentagonal cross-section while the funnel has a rectangular outlet opening.

Abstract: A cyclone furnace for a pulverized fuel boiler comprises a casing enclosing a cage of water tubes and having studs extending inwardly from each of the water tubes. Refractory tiles line the inside of the furnace, each fitted over a stud and secured in place thereby protecting the water tubes from the intense corrosion and abrasion. The furnace has three sections in which the design of the tiles vary. In the neck section the joints of the tiles are straight, in the barrel section they are curved and sympathetic to the gas flow and in the re-entrant throat the joints are shiplapped or rebated. Although the tiles may be generally rectangular in all sections, they are preferably hexagonal in the barrel.

Abstract: An in-bed tubular heat exhanger support structure comprising a plurality of fluid-cooled support tubes which extend over and are supported by the wall headers of a fluidized bed boiler. Each support tube has at least one upright portion which extends into the fluidized bed region of the boiler, and wherein at least one of the heat exchanger tubes is clamped or otherwise fixed to the upright portion of the support tube.

Abstract: A heat exchanger for use in a multi-solid fluidized bed heat generating system includes a housing for containing a flowing volume of hot gas and fluidized recirculating solid particulate material. The housing includes outer side walls, a top wall and an intermediate bottom structure comprising water wall panels for containing a flow of water/steam to be heated from the hot gas and solid material contained within the enclosure formed by the housing walls. A supply header is provided to direct water/steam to be heated into the water wall panels at a lower level and a takeoff header is utilized for removing the heated water/steam from the wall panels at an upper level. A fluidizing gas injector system is provided for directing a high velocity flow of gaseous fluid into the enclosure formed by the housing water wall panels at a lower level therein for fluidizing the recirculating solid particulate material, which material is recycled back into a combustion vessel of the fluidized bed heat generating system.

Abstract: A cyclone separator in which an outer cylinder is formed by a plurality of vertically-extending, spaced, parallel tubes and extends around an inner pipe in a coaxial relationship therewith to define an annular chamber. A portion of the tubes forming the outer cylinder are bent out of the plane of the cylinder to form an inlet opening in a tangential relationship to the annular chamber for receiving gases containing solid particles and directing same through the annular chamber for separating the solid particles from the gas by centrifugal forces. The tubes are bent radially inwardly towards the inner pipe to support the inner cylinder and water is passed through the tubes to cool the outer cylinder.

Abstract: The vapor generator is formed with a flue of rectangular cross section and a funnel of four trapezoidal walls which define a rectangular opening. The tubes of the funnel and flue extend helically and connect each to the other. The funnel tubes in the larger trapezoidal walls have transition portions which are disposed at greater angles to form a smooth transition into the funnel tubes of the smaller trapezoidal walls.

Abstract: An attachment arrangement for attaching a boiler casing to a membrane tube wall utilizes an extension plate which is connected to and extends beyond an edge of the casing. The extension plate and the surface of the casing adjacent its edge define an attachment area which is attached to the tube wall. A slot extends in the casing and through part of the extension plate. The slot is covered by an expansion element having a termination covering the end of the slot. The termination is on the extension plate. The termination of the expansion element extending over the extension plate provides compensation for expansion in the attachment area which avoids deformation and tearing of the casing in this area.

Abstract: A fluid, especially secondary air, feed nozzle of an incinerator furnace, in accordance with the invention, is made in two complementary recessed parts (11, 12). These parts are molded from refractory material (silicon carbide, for example) and assembled by pressing so as to have an outside shape identical to that of the bricks which constitute the wall of the furnace.

Abstract: An apparatus for gasifying coal dust has a housing provided with an output fitting for the removal of generator gas and an output fitting for the removal of granulated slag. An overflow maintains a body of liquid in the bottom of the housing and a coal-dust burner in the housing forms a downwardly moving coal-dust flame in an upper reaction zone of the housing. An annular tube wall in the housing upper and lower ends where its tubes are bent apart and form radially throughgoing upper and lower openings and at the burner and therebelow but above the generator-gas output fitting. This tube wall is radially gastight between its upper and lower openings and radially inwardly delimits an axially extending annular passage that is outwardly defined by the housing. Steam is fed to the upwardly directed lances in the passage to create in the housing a toroidal annular current of moving gas and steam rising in the passage and descending in the zones between the flame and the tube wall.

Abstract: A device for suspending a bundle of horizontal tubes in a vertical plane (1), the device comprising pairs (4, 5, 6) of vertical tubes (7, 8) provided with half-fins on their facing sides. The half-fins have a profile including notches of circular shape, having a radius slightly larger than the radius of the tubes in the bundle and being at the same spacing as said tubes, the notches being separated by tongues (16, 18, 20, 17, 19, 21) which project from the vertical tubes by a distance which is long enough to provide good support for the tubes of the bundle and which is short enough to ensure good thermal conduction from their projecting ends to their weld zones on the corresponding vertical tubes.

Abstract: A steam generator includes first and second mutually parallel flue gas flues; the first flue gas flue having an upper end, an intermediate ceiling at the upper end having an upper surface, a cross flue leading from the first to the second flue gas flue, and first and second vertical walls formed of pipes and disposed opposite each other as seen along the cross flue; a steam generator frame supporting the intermediate ceiling; the intermediate ceiling being formed of pipes gas-tightly welded to each other and disposed alongside each other in one layer in tube tracks extended along the cross flue; each of the pipes of the intermediate ceiling changing into a respective pipe of one of the vertical walls; and first and second vertical suspension pipes connected from a common location along a given one of the tube tracks through the upper surface of the intermediate ceiling and through the cross flue to the steam generator frame for suspending the intermediate ceiling, the first suspension pipe changing into a pip

Abstract: In a method for safely operating a coal gasifier which is indirectly cooled by passing a heat-carrying oil through a cooling jacket of the gasifier, the pressure of the heat-carrying oil is continually measured after having passed through the cooling jacket. If the measured pressure falls below a predetermined pressure, the supply of coal and gasifying agents to the gasifier is interrupted, the passage of heat-carrying oil is interrupted and water or steam is passed through the cooling jacket until the gasifier is safely shutdown.

Abstract: A heat exchanger panel having vertical tubes (1, 2) which form loops between an inlet (1A) and an outlet (1B) via which they are suspended from a rigid structure (3, 4), and intended to come into contact via their outer surfaces with a soot-laden gas characterized in that its tubes are separated from one another at a pitch which is a little greater than their diameter, in that the tubes of the central portion are interconnected by fins, and in that the end tubes directly connected to the suspension structure are fixed to one another and to the nearest adjacent tube by short members (14, 15) welded on either side to adjacent tubes (21, 22, 23) at a level below that of the top loops of the panel, and are connected to one another and to the adjacent tube below the fixing members by fins (26).

Abstract: An erosion resistant waterwall in which a plurality of erosion resistant stud members are attached to the exposed surface of a waterwall consisting of a plurality of spaced water tubes connected together by continuous fins. The size of the stud members relative to the tubes are such that a plurality of the stud members extend around the periphery of each exposed tubes surface in a spaced relationship in a direction perpendicular to the axis of each tube. The stud members may be in the form of steel balls or small rod members attached to the exposed surface, and a ceramic sleeve can extend around the rod members.

Abstract: A device for protecting wear of heat transfer tubes in a fluidized-bed boiler is disclosed. The protective device is applied to a portion of a heat transfer tube which is strongly and exceedingly attacked by fluidized bed materials, so that the considerable decrease in service life of a heat transfer tube due to wear caused by the attack of fluidized bed materials can be avoided.

Abstract: A seal assembly for a vapor generator each wall of which has spaced lower and an upper portions to accommodate relative movement there between. The seal assembly includes a trough containing water and connected to one of the portions of each wall. A dip skirt extends into the trough and divides same into an inner chamber and outer chamber, and a partition extends from the dip skirt, across the space between the wall portions, and to the other wall portion to expose the water in the inner chamber to the boiler pressure and the water in the outer chamber to atmosphere. As a result, relative movement between the wall portions is accommodated by corresponding movement of the dip skirt in the water trough while maintaining an airtight seal.

Abstract: A tube wall for a metallurgical furnace is mainly formed by an array of generally parallel tubes centered on respective tube axes and each having two widened open tube ends one of which projects laterally from the respective tube in one radial direction and the other of which projects laterally from the respective tube in the opposite radial direction. Each tube end laterally engages the tube end of an adjacent tube and the tubes are laterally spaced between their ends. Respective caps each cover two adjacent tube ends and interconnect same so that the interiors of the tubes and caps form a sinuous passage. Finally, respective welds secure the tube ends and caps together hermetically to seal off the passage. Thus appropriate means can circulate a coolant through the array. Such construction is sufficiently rigid to do away with webs laterally interconnecting the tube sections, thereby eliminating the cost of their manufacture and installation.

Abstract: A convective heater for heating fluids such as a coal slurry is constructed of a tube circuit arrangement which obtains an optimum temperature distribution to give a relatively constant slurry film temperature. The heater is constructed to divide the heating gas flow into two equal paths and the tube circuit for the slurry is arranged to provide a mixed flow configuration whereby the slurry passes through the two heating gas paths in successive co-current, counter-current and co-current flow relative to the heating gas flow. This arrangement permits the utilization of minimum surface area for a given maximum film temperature of the slurry consistent with the prevention of coke formation.

Abstract: The support girders of the heat exchanger are connected at the ends to a tension band on an adjacent wall by a connection with transfers stress in a symmetric manner. A connecting element is welded to a tension band in a symmetric manner and carries pivot links which, in turn, are articulated to the end of a girder. Loads from the girder are transferred to the tension band in the central plane of the tension band.