Abstract: A process for the removal of a high percentage of NOx and SOx from the gaseous effluent of a metal pickling operation comprising passing the effluent through an aqueous scrubber, treating the gaseous effluent from the scrubber with ozone, passing the effluent from the ozone treatment through a second aqueous scrubber thereby removing at least 80 vol % of the NOx and SOx present in the original effluent. The scrubbing solutions in both of the scrubbers preferably have a pH of from 7 to 14, more preferably 10 to 14. The scrubbing solutions in both scrubbers are caustic solutions containing sodium hydroxide or calcium hydroxide. The NOx and SOx in the scrubbers are converted into nitrate salts and sulfate salts, which are removed from the scrubbers.

Abstract: A furnace, for instance a reflow soldering oven, in which oxygen concentration is either directly or inferentially sensed within central processing and either one or both of the inlet and outlet sections of the furnace. Signals generated by these sensors are processed in a PID controller to generate a control signal to control the flow rate of inerting gas into the central processing section, thereby to at least inhibit ingress of air into the central processing section. The PID controller is programmed such that its integral error term is set equal to a time average of the oxygen concentrations of the central processing section less an oxygen concentration set point desired for the central processing section. The proportional and differential error terms are set equal to a time average of the concentrations of the central processing section and one or both of the inlet and outlet sections of the furnace less the oxygen concentration set point.

Abstract: A process for recovering a given component from a first gas stream in which the given component is intermittently present by PSA or TSA using an adsorbent which more strongly adsorbs the given component by introducing into the first gas stream, prior to PSA or TSA treatment, a second gas stream that is enriched in the given component. The second gas stream may be introduced into the first gas stream only during periods when the concentration of given component in the first gas stream is below its maximum concentration or it may be continuously introduced into the first gas stream at a level which is greater than the maximum concentration of given component originally present in the first gas stream.

Abstract: Method for heat treating a metal in which argon gas is selectively injected into the cooling zone of a heat treating apparatus when the temperature therein is above the level at which significant nitriding will occur.

Abstract: A wave soldering process and apparatus in which a localized low oxygen-containing atmosphere is provided at the point of contact of the solder wave and the substrate to be soldered by bubbling an inert gas through the solder wave.