Abstract: A process for removing dichromates from chlorate-rich solutions containing hypochlorite and dichromate ions and produced by the electrolysis of brine. The dichromate is reduced in a two-stage process by the addition of ammonia under controlled conditions of pH and temperature to a mixed di- and trivalent chromium hydroxide which is precipitated from solution and removed. The process provides an economical method of recovering chromium from electrolytically produced chlorate solutions.

Abstract: A continuous bucket conveyor/elevator is provided which comprises a series of buckets mounted on at least one endless cable. The cable or cables and attached buckets are urged forward by means of an adjacent driving mechanism, such as, a pneumatic or hydraulic piston, which engages contact members attached at intervals to the cables. Because no drive chains or sprocket wheels are employed, lubrication is minimized even in corrosive or abrasive environments.

Abstract: A plurality of electric blasting caps are fired through the ignition system which includes a transformer having a primary winding and a secondary winding. The secondary winding of the transformer is connected to the resistive elements of the blasting caps through a blasting circuit which is electromagnetically coupled to the resistive elements of the blasting caps via a small toroid transformer. A D.C. voltage is stored on a storage capacitor which has one end connected to the center point of the primary winding. The other ends of each half of the primary winding are connected through a driver circuit to ground. Each driver circuit is enabled by a flip-flop at predetermined intervals, whereby the storage capacitor will discharge through the appropriate half of the primary, to thereby produce a pulse train at the output of the secondary. The pulse train provides the ignition power for igniting the electric blasting caps.

Abstract: An improved process for the manufacture of water resistant dry blasting agents. Powdered, solid, water blocking agent and solid fuel, if required, is added as a suspension in a liquid non-hydrating fuel phase to porous ammonium nitrate prills. The process thus avoids unevenness of coating with water blocking agent of prior art processes and is particularly suited to on-site truck mounted manufacturing of water resistant blasting agents.

Abstract: Absorption and drying towers for treating sulphur trioxide process gases and air, respectively, with concentrated sulphuric acid in the manufacture of sulphuric acid. Each tower has a suitably shaped downwardly angled gas delivery duct protruding into a lower chamber of the tower to prevent acid from entering inside the duct. Each tower also has its lower chamber defined by the base of the tower and a suitably formed packing support. Additional packing is interposed between the lower walls of the tower and the packing support. Improved corrosion resistance of the metal components is obtained.

Abstract: A novel heterogeneous, cap-sensitive high explosive is provided which comprises a crystalline inorganic nitrate salt having dispersed throughout the matrix of the salt crystal a hydroxyalkyl nitrate fuel. Particularly preferred are ammonium nitrate crystals having dispersed therein ethylene glycol mononitrate. The crystalline high explosive is dry and free flowing and may be used per se, in admixture with bulking agents or fluidizing agents or may be used as a replacement for a substantial amount of nitroglycerine in conventional dynamite compositions.

Abstract: A process for the management of by-product tetranitromethane (TNM) which avoids the hazards of the prior art isolation or extraction procedures. A selected in-plant liquid or vapor stream, or a reactor off-gas stream from nitration or nitric acid oxidation plant, which contains TNM, is heated to effectively pyrolyze the TNM without undue losses of nitric acid values.

Abstract: Process for the production of sodium chlorate by the electrolysis of sodium chloride contaminated with sodium sulphate wherein the sulphate concentration in the system is kept below a pre-selected level. A portion of the mother liquor remaining after crystallizing out some of the sodium chlorate product is selectively further cooled to effect crystallization of some of the sodium sulphate present in the liquor. An acceptable "steady-state" concentration of sulphate ion is established which prevents the deleterious excess sulphate ion build-up in the electrolytic system.

Abstract: A method of smooth wall rock blasting is provided in which an alignment of boreholes for explosive charging is drilled into rock and a single, smaller diameter empty borehole is drilled close and parallel to, and on each side of each charged borehole. Upon detonation of the charged boreholes, the rock is cracked smoothly along the plane coincident with the axes of the holes. The method reduces drilling costs to a minimum and provides improved results over the previous pre-shearing and other known methods.

Abstract: A packaged booster charge is provided which is sensitive to initiation by blasting cap yet which contains no self-explosive ingredient. The composition of the booster comprises a low melting point nitrate salt or salt mixture having dissolved or finely dispersed therein an acetylenic substance and void containing material. The booster is safe and economic to manufacture and sufficiently powerful to initiate insensitive blasting agents.

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 cold-drawn unbalanced biaxially oriented linear low density polyethylene film having a transverse direction draw ratio selected from greater than 1 to less than 3 and a machine direction draw ratio of less than 6 but greater than the transverse direction draw ratio. The film has enhanced tensile and puncture resistance while maintaining acceptable tear properties and is used for shipping sacks.

Abstract: A shipping sack having walls formed of uni-axially oriented linear low density polyethylene film wherein said film is produced by blowing and cold drawing said polyethylene at a draw ratio to blow ratio of greater than 1:1, preferably, between 2:1 and 5:1. The sack can be used as a tubular shipping sack for bulky, lightweight material or, if optionally provided with a double inner film of low density polyethylene, as a heavy duty sack. The sacks have improved physical properties.

Abstract: Process and apparatus for the generation of sulphur trioxide from oleum using microwave energy for use in the sulphonation and nitration of organic compounds and the fortification of oleum. The process provides improved control of production and concentration of the sulphur trioxide produced and comprises subjecting sulphur trioxide-rich oleum feed to microwave energy for a sufficient period of time to produce sulphur trioxide vapour and spent oleum; isolating said sulphur trioxide vapour and collecting said spent oleum.

Abstract: Process and apparatus for the generation of sulphur dioxide vapor from contaminated liquid sulphur dioxide. The process allows of utilization of contaminated liquid sulphur dioxide and comprises subjecting liquid sulphur dioxide feed to microwave energy for a sufficient period of time to produce sulphur dioxide vapor, collecting said vapor and removing resultant contaminated liquid sulphur dioxide, if any.

Abstract: This invention relates to a process for the production of concentrated sulphuric acid from waste sulphuric acid which comprises subjecting said waste acid to microwave energy for a sufficient period of time to effect production of water vapor, whereby said waste acid is concentrated to a desired degree; removing said water vapor; and collecting said concentrated acid.

Abstract: A thermoplastic shipping bag having a thermoplastic inner ply comprising a mesh which permits the packaging of finely powdered materials without releasing unacceptable levels of powders to the atmosphere during or after filling and without requiring significant modification to packaging systems used to fill and process multi-wall paper shipping bags.

Abstract: A continuous process for the generation of sulphur trioxide from oleum suitable for use in the sulphonation of organic compounds which comprises continuously introducing oleum feed to a sulphur trioxide desorption tower; continuously introducing a recycled dry feed air stream to said desorption tower, whereby a gaseous mixture of sulphur trioxide in air is produced; collecting spent oleum from said desorption tower; introducing said gaseous mixture to a sulphonation reactor; and recycling spent gaseous mixture from said reactor to said desorption tower as said feed air stream. The process offers reduced environmental pollution and operating costs.

Abstract: An absorption tower for absorbing sulphur trioxide in sulphuric acid having distinct upper and lower packed absorption zones wherein substantially all of the sulphur trioxide is absorbed by the sulphuric acid in the lower zone, while in the upper zone the depleted gas stream is significantly cooled. The two zones receive feed acids of different temperatures and different acid irrigation rates. The tower allows of improved energy recovery while providing for environmentally acceptable emission standards.

Abstract: An apparatus and method is provided for measuring the continuity and resistance of electric circuits, particularly electric wire circuits used in blasting, in the presence of spurious voltages due to galvanic currents. A constant current from a cell is passed through the electric circuit to be tested and through a reference resistor where the voltages are measured to derive the resistance of the circuit. The measured voltages are sensed with a converter converted to a resistance measurement and displayed. The presence of spurious voltages is compensated for by connecting a galvanic current storage capacitor in the circuit, passing a reference current through the reference resistor and the circuit and comparing the voltage across the reference resistor with the voltage across the circuit and storage capacitor to derive a resistance reading. The reading is converted to a digital display.