| 摘要 |
<p>A container (13) is arranged to be filled with a dry precursor material and the top of the container is welded shut. The container has a generally cylindrical shape with at least a partially corrugated side wall (23). The top of the container (27) has a filling port (21) and a plug (22) adapted to fit therein. A cylindrical liner (24) fits snugly within the container (13) and extends between an inlet and outlet filter (25) and (26) which are located at the bottom (20) and top (27) of the container respectively. At the centre of the top of the container (27), a gas outlet is provided (28), the gas outlet (28) is in the form of a vertical extending pipe which passes through the plug (22) and terminates in a transverse perforated pipe (29) at its lower end. The perforated pipe (29) is separated from the dry percursor material within the container by the outlet filter (26). At the bottom of the container, a gas inlet (30) is provided in one side wall of the container, inside the container the pipe (30) extends horizontally parallel to the bottom of the container. It is also perforated and is separated from the dry precursor material by the inlet filter (25). The container is heated in either a batch or continuous process while a reducing gas such as hydrogen or nitrogen is introduced at the gas inlet (30). This gas passes from the perforated pipe (31) and eventually passes through outlet pipe (28). The container is heated for a time sufficient to ensure that substantially all the nitrates within the dry precursor material have been decomposed and removed.</p> |
