A twin plasma apparatus including an anode plasma head and a cathode plasma head. Each of the plasma heads includes an electrode and a plasma flow channel and a primary gas inlet between at least a portion of the electrode and the plasma flow channel. The anode plasma head and the cathode plasma head are oriented at an angled toward one another. At least one of the plasma flow channels includes three generally cylindrical portions. The three generally cylindrical portions of the plasma flow channels reduce the occurrence of side arcing.