Abstract: A filtration module is provided using metallic interconnect tubes that are sealed to carbon or ceramic based tubular filtration elements and that are also sealed to metallic tubesheets which are sealed to a filter housing. A sealed joint is formed between the interconnect tubes and the filtration elements using a metal alloy and an optional metallic plating on the filtration elements. In order to reduce or prevent undesired wicking of the alloy into the filtration element, refractory small solid particles may be added to or formed in the alloy to block the pores and channels in the filtration element at the site of the joint. Wicking can also be reduced by induction, torch or other type of heating where only those portions of the filtration element at the site of the joint is heated so that temperatures adjacent the site are below the solidus temperature of the alloy.

Abstract: Heavy metals substantially free from heavy metal chloride contaminants are recovered from electric arc furnace (EAF) dust by bringing the dust into contact with a carbonaceous reductant utilizing a plasma arc of a DC sealed atmosphere plasma arc furnace so as to volatilize (vaporize) the hazardous heavy metals therein, and then bringing the vaporized heavy metals into contact with an alkali metal gettering agent to thereby form alkali metal chlorides and thereby substantially inhibit the formation of heavy metal chlorides in the off-gas.

Abstract: Chemical agents, such as chemical munitions, are decomposed by bringing them into contact with a plasma arc of a DC plasma arc furnace operated at a temperature of greater than about 30,000.degree. F.