Abstract: A combined sulphur burning furnace and water-cooled boiler arrangement for producing a cooled, gaseous sulphur dioxide-air mixture in which the furnace is located below the boiler tubes arrangement in a vertical, cylindrical shell. The hot gases produced in the furnace exit axially into an upper chamber defined by the water-tube arrangement and pass through the cooling water-tube arrangement in radial outward flow to an outer chamber provided with cold-side by-pass control means and then exit the shell. The apparatus provides for savings in ducting, foundations, piping and the like; and permits more efficient sulphur burning and cooling.

Abstract: In a system using the double absorption process for sulphuric acid manufacture, a single acid circulation system and a single cooler are employed. Acid from the exit of the air drying tower and final absorber tower are mixed in a common reservoir, while acid from intermediate absorber tower is discharged to a separate reservoir. Acid from the common reservoir is split between the intermediate and final absorber towers and product line. Acid from the separate reservoir is cooled and split between the drying tower and intermediate absorber tower. The circulation arrangement reduces the cooling to one relatively high temperature location and simplifies acid strength and level control. Only half of the bulk of the circulating acid has to be cooled and the effect of seasonal fluctuating temperatures in the drying tower is minimized.

Abstract: An anodic protection system particularly useful in heat exchangers for cooling sulphuric acid, in which the cathode projects through both ends of the heat exchanger and a negative potential is applied to both ends of the cathode. The potentials are controlled to ensure that the hot and cool ends of the heat exchanger metal (tubes and shell) which ends have different potential requirements for remaining in the passive range, both remain within their respective passive ranges.

Abstract: Process for the production of liquid sulphur dioxide in a sulphur dioxide facility forming part of a sulphuric acid plant wherein a portion of the sulphur dioxide produced in a sulphur burning furnace is directed to a sulphur dioxide liquefaction means and the resultant tail gas is recycled to the furnace. Relatively high sulphur dioxide concentrations are maintained in all parts of the sulphur dioxide production cycle allowing higher strength sulphur dioxide gases to be generated without overheating the furnace and also lower power requirements in the sulphur dioxide liquefaction step.

Abstract: A thermoplastic heavy duty shipping bag having walls formed of cross-laminated outer plies of uni-axially oriented polyethylene and inner walls of low density polyethylene, heat sealed thereto. The bag provides improved puncture and snag resistance.

Abstract: A well casing packer includes a seal mechanism, mounted on a mandrel. The casing packer comprises a seal element and a wedge member for driving the seal element radially outward against a well casing by applying radial forces to the seal element. This wedge member and a support member support the seal element to maintain the radial forces on the seal element, and the support member and the wedge member are constrained to move together during the driving of the seal element against the well casing. The casing packer also includes a mechanism for releasing the radial forces on the seal element, which comprises a member for releasing the constraint between the wedge and support members to allow these members to be longitudinally driven relative to one another to remove the support on the seal element by the wedge member, and thereby release the radial forces on the seal.

Abstract: A process for producing concentrated sulphuric acid from a hot gas stream comprising water and sulphur trioxide which process comprises feeding a first portion of said gas stream through a first sulphur trioxide absorption zone and a second portion through a second sulphur trioxide absorption zone; feeding a recycled sulphuric acid stream to said first sulphur trioxide absorption zone whereby substantially all of the sulphur trioxide and sulphuric acid are removed from said first portion of said gas stream to produce an enlarged sulphuric acid stream; recycling a first portion of said enlarged sulphuric acid stream through said first sulphur trioxide absorption zone; feeding a second portion of said enlarged sulphuric acid stream to said second sulphur trioxide absorption zone; and collecting sulphuric acid product from said second sulphur trioxide absorption zone; wherein the ratio of gases to sulphuric acid in said second sulphur trioxide absorption zone is such that the sulphuric acid product leaving said

Abstract: Apparatus and process for the manufacture of sulphuric acid by the contact process of the type comprising at least one gas-concentrated sulphuric acid contacting unit and a sulphuric acid heat exchanger characterized in that the contacting unit and/or heat exchanger is formed of high silicon content austenitic steel. The steel is also of use in sulphuric acid concentrators. Reduced corrosion rates are provided.

Abstract: A non-electric detonator assembly is provided for initiation by means of a connected length of low energy detonating cord. The assembly comprises a substantially conventional instantaneous or delay period non-electric blasting cap containing a detonating cord attachment plug element in its open end. The plug element is adapted to receive a secured bend of low energy detonating cord and to transmit initiating energy from the cord to the cap. Use of the assembly allows for the convenient assembly of the cord/cap combinations in the field and eliminates wasted cord.

Abstract: A tubular joint sealing system for use in high pressure and high temperature conditions is provided. The sealing system consists of a shape memory material backup member combined with a compliant seal. The shape memory member is deformed into an intermediate shape that is sufficiently reduced in size so as to avoid abrasive contact with the sealing surfaces of the tubular members during the mechanical makeup of the joint. Thereafter, the shape memory member may be activated to assume its memory shape configuration, which is selected to be sufficient size to form a pressure and fluid-tight seal.

Abstract: A method of charging upwardly extending, large diameter boreholes with cylindrical explosive cartridges is provided employing a longitudinally inflating flexible tube as the pushing mechanism. A fluid-impervious flexible tube is turned over or everted at one end and secured. A fluid, preferably air, at about 3 psi is passed into the tube causing the tube to elongate and the everted tube face to travel along the length of a borehole. An explosive cartridge mounted against the tube face is carried to a desired location in the borehole after which the tube is partly deflated and withdrawn from the borehole.

Abstract: A method of charging a borehole with a column of explosives is described wherein the explosive charge is detonable in time-delay sequence by means of electrically initiated detonators. The method requires providing a loop of an insulated electrical conductor throughout the length of the borehole and, as the borehole is charged with explosives, sliding electrically actuable time-delay detonators along the wire so as to be positioned at intervals throughout the borehole. The detonators are electrically coupled to the looped wire by means of slidable toroidal transformer cores. The wire loop, in turn, is electromagnetically energized by means of a second transformer core and an energy source. The method provides for safe and efficient borehole charging and avoids the hazards associated with usual electric detonator systems.

Abstract: A means is provided for stabilizing polysaccharide-thickened aqueous solutions by including in the thickened solution from 0.01% to 1% w/w of a thiuram sulphide or thiomorpholine compound as stabilizer. These stabilizers provide improved resistance against breakdown of the gels and separation of the gel ingredients particularly when the gels are exposed to elevated temperatures. The invention has application in the fields of paints, pharmaceuticals, printing, explosives or wherever polysaccharide-thickened aqueous solutions are employed.

Abstract: In a bandmill having a column and a pair of arbor-supported wheels carrying and driving an endless saw, a mechanism is provided to move the first wheel relative to the second wheel to accommodate fluctuations resulting from saw loading conditions; the mechanism comprises: a vertical post having one end slidably received in the column; a horizontal plate fixed to the other end of the post; a arbor support fixedly mounted to the plate and having a hinge portion; a tension arm having a first portion attached to the arbor and a second portion extending lengthwise over the plate; and resilient elements located between the second portion of the tension arm and the plate.

Abstract: In conventional processes for manufacturing phosphoric acid, sulphuric acid is reacted with phosphate rock to produce weak phosphoric acid which is concentrated using steam from the associated sulphuric acid manufacturing operation. Low grade heat from the absorbers and drier of the sulphuric acid manufacturing plant has been wasted. According to the invention waste heat from the drier and one or more absorbers of the sulphuric acid manufacturing plant is used in all the evaporators of the phosphoric acid plant. The evaporators all operate at low pressures and their heaters are arranged in series, to enable the heat to be used at the relatively low temperatures available. The valuable steam is thus freed for other uses.

Abstract: An explosive or stemming package is provided which is self-retaining in vertical or inclined up-holes in stable rock. The package containing a flowable material, for example, slurry explosives, consists of a thin-walled cylindrical bag having at least one longitudinal, external pleat held closed by means of an adhered overcovering or tape. With the package held in position in the up-hole by a push rod, the tape is severed by means of a rip cord allowing the pleat to open. The slumping contents press the package closely against the borehole wall for secure retention without additional support. Improved coupling of the explosive charge to the rock is also provided giving enhanced blasting efficiency.

Abstract: An emulsion explosive composition comprising an oxygen-supplying salt component as a discontinuous phase, an organic medium forming a continuous phase and an emulsifying agent which comprises at least one conventional emulsifier and at least one emulsification enhancer. The compositions are easily emulsifiable.

Abstract: A process and apparatus is provided for the continuous manufacture of a water-in-oil explosive emulsion precursor. Separate streams of the water phase component and the oil phase component are introduced into an in-line motionless mixer. A chosen portion of the output from the mixer is recirculated and returned to the motionless mixer for further emulsification. The process allows for the production of a very high phase ratio water-to-oil emulsion (up to 95% water phase) without phase inversion after long storage. The precursor is simply converted to a sensitive explosive by means of known density lowering techniques.

Abstract: A water-in-wax emulsion explosive composition is provided wherein the continuous carbonaceous fuel phase comprises paraffin wax together with a minor amount of a rheology modifier and stabilizer combination comprising an ethylene-containing polymer and a low molecular weight hydrocarbon liquid. The resulting explosive composition exhibits properties of viscosity and stability comparable to similar compositions containing highly refined microcrystalline wax fuels.

Abstract: A method and apparatus is provided for the efficient and safe manufacture of batch quantities of non-cap-sensitive emulsion explosives. The method employs none of the high shear mixing or homogenizing techniques of the prior art and hence hazards from heat and mechanical breakdown (impact) are eliminated. The method consists of tumbling the oil phase of the emulsion in a rotating, internally baffled mixer and slowly adding thereto the aqueous phase. The resulting emulsion explosive is detonable by boostering in large diameter charges.