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 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 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: 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: 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.