Abstract: A method comprises providing a first gas stream containing a first concentration of sulfur dioxide; passing the first gas stream through at least a first catalyst volume whereby at least a portion of the sulfur dioxide is reacted to produce sulfur trioxide and removing from the at least a first catalyst volume a first treated gas stream containing sulfur trioxide and unreacted sulfur dioxide wherein the reaction of sulfur dioxide to sulfur trioxide is not limited by catalyst volume; providing a second gas stream containing a second and higher concentration of sulfur dioxide; and, passing the first treated gas stream and the second gas stream through at least at least a second catalyst volume to produce a second treated gas stream containing sulfur trioxide and unreacted sulfur dioxide.

Abstract: A heat exchanger for use in a sulphuric acid manufacturing plant to effect heat transfer between desired gas streams selected from air, sulphur dioxide and sulphur trioxide. The exchanger provides for hot or cold split flow gas streams through the exchanger shell with either mixing or splitting into two or more streams to provide for reduced condensible material condensation, corrosion, metal thermal differential stress and capital equipment cost. A preferred exchanger is used in combination with a sulphur burning furnace to provide an improved preheater.

Abstract: A heat exchanger for use in a sulphuric acid manufacturing plant to effect heat transfer between desired gas streams selected from air, sulphur dioxide and sulphur trioxide. The exchanger provides for hot or cold split flow gas streams through the exchanger shell with either mixing or splitting into two or more streams to provide for reduced condensible material condensation, corrosion, metal thermal differential stress and capital equipment cost. A preferred exchanger is used in combination with a sulphur burning furnace to provide an improved preheater.

Abstract: A shell and tube heat exchanger for exchanging heat between a shell side fluid and a tube side fluid has a longitudinally extending shell, a longitudinally extending tube bundle and one or more baffles positioned within the shell for directing the shell side fluid to flow across the tube bundle. One or more valves is also provided within the shell of the heat exchanger. Each valve is operable between a first position and a second position and co-operates with a baffle for adjusting the flow of shell side fluid through the shell side of the exchanger. Each of the valves is controlled by an external actuator.

Abstract: A liquid distributor for use within a cylindrical tower containing tower packing to provide dispersed liquid to the packing comprising (a) a plurality of cordially disposed feed liquid conduits interconnected one to another to form, at least, one coplanar essentially continuous loop, (b) a feed entry for feeding the liquid to the conduits, and (c) sprayers for dispersing the liquid onto the packing. The distributor is of particular value in the sulfric acid manufacturing field as a drying tower, sulfur dioxide stripping tower, sulfur trioxide absorption tower and an oleum tower. The distributor provides improved irrigation across the tower and, particularly, adjacent the tower wall.

Abstract: An improved packed tower for effecting the absorption of a gas into a liquid, comprising a cylindrical tower wall defining a packing zone; a plurality of packing pieces contained within the packing zone; a liquid distributor above the packing zone for distributing liquid onto the packing pieces; a gas feed inlet below the packing pieces for feeding gas through the packing zone, the improvement wherein the plurality of packing pieces comprises a first plurality of packing pieces, of a first packing piece size, disposed within a first region of the packing zone defining an annulus adjacent at an upper part of the tower wall, and a second plurality of packing pieces of a second packing piece size greater than the first packing piece size, within a second region of the packing zone. The packed tower provides higher efficiencies in gas absorption over prior art towers as to offer reduced tower and/or packing heights.

Abstract: A shell and tube heat exchanger for exchanging heat between a shell side fluid and a tube side fluid has a longitudinally extending shell, a longitudinally extending tube bundle and one or more baffles positioned within the shell for directing the shell side fluid to flow across the tube bundle. One or more valves is also provided within the shell of the heat exchanger. Each valve is operable between a first position and a second position and co-operates with a baffle for adjusting the flow of shell side fluid through the shell side of the exchanger. Each of the valves is controlled by an external actuator.

Abstract: A process for concentrating a waste sulphuric acid stream containing metal sulphates including iron sulphate comprises the steps of subjecting the stream to an ion exchange operation to produce an acid-rich stream and a salt-rich stream and, concentrating the acid-rich stream to produce a concentrated sulphuric acid stream.

Abstract: An improved tower saddle packing having a general shape that is a segment of a hollow torus. The circumferential outer edges of the saddle define a plurality of radially, outwardly extending convex lobes. The lobes and wing portions preferably have weep holes to effectual wetting of all surfaces of the saddle. The hub of the saddle has in one aspect a plurality of apertures extending substantially across the hub. The saddle provides improved gas-liquid interaction, permits enhanced gas throughput in an absorption tower and allows for reduced tower packing sections.

Abstract: A heat exchanger and process for use with a corrosive fluid, such as sulphuric acid, having an anodic protection system for protecting the acid-contacted surfaces wherein the anodic protection system has a plurality of elongated cathodes of such cross sectional area and length as to operably maintain voltage losses due to current flow along the cathodes at values less than the allowable passive voltage ranges at the acid-contacted surfaces.

Abstract: A catalytic converter for converting sulfur dioxide to sulfur trioxide comprising an exterior shell of a heat resistant weldable metal; foundations from which the shell vertically extends; an interior tube of same metal vertically disposed within the shell and defining a passage; the interior tube having i. a first inlet aperture through which the passage receives a first portion of a sulfur dioxide-containing gas from a source of such gas; ii. a second inlet aperture through which the passage receives a second portion of the sulfur dioxide-containing gas; and iii.

Abstract: The invention provides in one broad aspect an improved process fluid preheater system for raising the temperature of a process fluid with a hot furnace gas, having a combustion furnace in communication with a shell and tube heat exchanger, wherein the furnace operably produce the hot furnace gas and comprises air inlet means, fossil fuel combustion means and hot furnace gas exit means; and the heat exchanger comprises an exchanger shell, a first end radial tube sheet and a second end radial tube sheet, which define a shell space; a plurality of longitudinal tubes retained by the first and second end tube sheets within the shell and comprising heat exchange means; hot furnace gas inlet means; cooled furnace gas outlet means; process gas inlet means; and heated process fluid outlet means; the improvement comprising the plurality of tubes further comprises the hot furnace gas inlet means and the cooled furnace gas outlet means; the hot furnace gas exit means in communication with the plurality of tubes furnace g

Abstract: In the purification of gases generated in metallurgical and similar furnace operations, the impurities include solid particles and compounds or elements which are gaseous at the furnace temperatures and only form solid or liquid at temperatures approaching ambient conditions. Proper cleaning therefore requires cooling of the gases to at least the water dew point to cause these impurities to form as particles or droplets. This invention describes an apparatus for collecting such particles or droplets in which a charging device and condensation equipment are combined to provide a simple, yet effective apparatus at a fraction of the cost of conventional apparatus.

Abstract: Apparatus and process for the production of gaseous sulphur dioxide mixture for conversion to sulphur trioxide in a catalytic converter in the production of sulphuric acid by the contact process. Apparatus comprises the furnace to produce sulphur dioxide gas from elemental sulphur and a first dry air stream; means for feeding a first portion of the sulphur dioxide gas to a waste heat boiler to cool the gas; the improvement comprising combining a second portion of the sulphur dioxide gas exiting the furnace with a second dry air stream to provide a combined gaseous stream which bypasses the boiler and subsequently is combined with the cooled sulphur dioxide stream. The system provides use of a bypass valve which experiences only cooled sulphur dioxide containing gases with its attendant reduced corrosion. Further, the system may operate at higher temperatures than is common to provide further advantages.

Abstract: A converter comprising an exterior shell of a strong, heat resistant weldable metal having an interior core tube formed of such metal and vertically disposed, partway within the shell from an upper part thereof. A foundation is provided from which the shell vertically extends. A plurality of catalyst beds are arranged one above the other within the shell and comprise at least one full catalyst bed having a first full bed extending essentially across a lower part of the shell, and at least one annular catalyst bed having a first annular bed between the shell at an upper part thereof and the core tube. Partitions define with the core tube a plurality of distinct, non-concentric, non-coaxial gas passages within the core tube. Each of the annular beds is in singular, gaseous communication within the shell with at least one of the passages. The converter has minimal axial gaseous flow transfer passages for maximum catalyst bed volume while preserving axial access to the beds.

Abstract: In the purification of gases generated in metallurgical and similar furnace operations, the impurities include solid particles and compounds or elements which are gaseous at the furnace temperatures and only form solid or liquid at temperatures approaching ambient conditions. Proper cleaning therefore requires cooling of the gases to at least the water dew point to cause these impurities to form as particles or droplets. This invention describes a process and apparatus for collecting such particles or droplets in which a charging device and condensation equipment are combined to provide a simple, yet effective apparatus at a fraction of the cost of conventional apparatus.

Abstract: A heat exchanger for exchanging heat between fluids comprising a shell and five tube bundles laid out as to collectively form a series of concentric pentagons, wherein each adjacent pair of tube bundles define an angle of 108.degree. and extend longitudinally within said shell and define a central space between them, said central space also extending longitudinally in said shell and being parallel to said tubes; each tube bundle consisting of a plurality of longitudinally extending parallel tubes in end view laid out in a set of parallel lines wherein each tube on a first parallel line with the two nearest tubes each on a second line adjacent to said first line forms an isosceles triangle having one angle of 72.degree. and two angles each of 54.degree.. This allows simple heat exchanger tube layout which is easy to fabricate and provide a compact tube bundle. The tube layout utilizes core tube entry of fluids and can accommodate internal core tubes or bypasses to cope with differential expansion.

Abstract: An improved catalytic converter having a shell, a plurality of horizontal catalyst bed supports upon which catalyst is retained and arranged one bed support above another within the shell, and a plurality of horizontal divider plates, one located between each pair of bed supports; the improvement comprising wherein at least one of the bed supports comprises a first full bed support extending essentially across the diameter of the shell, the full bed support comprising (i) an inner dished plate, centrally and symmetrically disposed within the shell, and (ii) an annular dished plate between the shell and the inner dished plate; a substantially circular gas entry port and a substantially circular gas exit port within the shell in gaseous communication with the first full bed support; and a substantially dished divider plate extending essentially across the diameter of the shell above the first bed support and comprising (i) an inner divider plate, centrally and symmetrically disposed within the shell and (ii) an

Abstract: A combined spray dryer and gas filter vessel in which a solution containing sulphuric acid and solids, and a hot drying gas, are introduced vertically through the top of the vessel into a spray zone. Solids are removed at a single point at the bottom of the vessel. Filters located above the spray zone clean gas leaving the vessel, and the cleaned gas exits at the top of the vessel. The compact design reduces insulation requirements while avoiding condensation which would create corrosion and yet it provides good separation of solids from gases.

Abstract: Dilute waste sulfuric acid is concentrated by heating it against product acid and then passing it through two contact zones separated by a collection zone. The dilute acid scrubs vapour produced in the collection zone and from a high temperature acid reboiler. In the collection zone acid is drawn off, heated, and recirculated to the collection zone where part of the liquid flashes to vapour. The main heat input is to the more dilute low temperature recirculating acid from the first contact zone rather than to the more concentrated high temperature acid in the reboiler. As a result, less sulfuric acid vapour is generated; the major portion of the heat can be fed to the process at low temperature; and only a single column is required, having a single cool clear water vapour exit stream to dispose of.