Abstract: A liquid injection device (11) for injecting cleaning liquids into an airflow, comprises: an airflow duct (12); a jacket (13) surrounding the airflow duct, in two parts (13a, 13b), axially separable, and having liquid infeed and drain openings (15); at least one nozzle unit (16) having an inlet opening (16a) onto the jacket, and its nozzle outlet opening (16b) into the airflow duct; the parts of the jacket being sealingly juxtaposed for use, and separable for access to said nozzle unit.

Abstract: A liquid injection device (11) for injecting cleaning liquids into an airflow, comprises: an airflow duct (12); a jacket (13) surrounding the airflow duct, in two parts (13a, 13b), axially separable, and having liquid infeed and drain openings (15); at least one nozzle unit (16) having an inlet opening (16a) onto the jacket, and its nozzle outlet opening (16b) into the airflow duct; the parts of the jacket being sealingly juxtaposed for use, and separable for access to said nozzle unit.

Abstract: A method for cleaning the interior walls of a storage tank comprises traversing over said walls a cleaning head supplied with air. The cleaning head may comprise a cleaning duct having an inlet and an outlet and a lateral opening which in use is sealingly arranged against the tank wall, whereby air flowing through the duct flows over and in contact with the tank wall. Cleaning materials, such as aggregate particles and cleaning fluid droplets, may be entrained in the air.

Abstract: A method for clearing pipework in an oil refinery includes the steps of: blowing, using a first, low velocity gas flow, pipe contents out of the pipework in such fashion that the contents are removed using gas overpressure, to leave a low contents residue; and substantially clearing the residue by a second, high velocity gas flow, the gas flows being such as not to give rise to a hazardous reaction such as fire or explosion. Apparatus for the same includes gas blowing means connectable to the pipework; valving adapted to throttle down an outlet of the pipework, said blowing means and valving being adapted to cooperate to effect both low velocity flow and high velocity flow through the pipework; and gas supply means to the blowing means supplying a gas that will not give rise to a hazardous reaction such as fire or explosion.