Formed in 2006 from the wastewater-products business of CDS Technologies, Rosedale-based Process Wastewater Technologies LLC manufactures sludge thickening and dewatering equipment, along with screening systems for combined and sanitary sewer overflows. PWTech’s Volute™ technology is its signature, combining thickening and dewatering in compact, automated equipment used throughout North America. The company manufactures in the United States exclusively with American-produced stainless steel, using no carbon steel.