Apparatus And Method For Taking Gaseous Samples

A method for cleaning an apparatus for taking samples of a gaseous medium containing solid particles, said apparatus comprising a pipe having one end adapted for introduction into said gaseous medium, a tubular filter for filtering off the solid particles, said filter being positioned coaxially with the pipe and communicating with the interior of the pipe, a removable closure being positioned on the downstream side of the tubular filter and coaxially with the pipe and withdrawal means for withdrawing the filtered gaseous medium from the outer side of the tubular filter and separate blow back means in communication with the outer side of the tubular filter, said method comprising the steps of:

• introducing a first cleaning gas to the outer side of a tubular filter via separate blow back means;
• passing the cleaning gas from the outer side of the tubular filter to the inner side of the tubular filter;
• introducing a stream of a second cleaning gas coaxially with the axis of the pipe so as to carry particulate matter to the end of the pipe adapted for introduction into the gaseous medium.

A method according to claim 1, wherein the removable closure comprises an access port positioned coaxially with the pipe.

A method according to claim 1, wherein the pipe has cooling means for cooling the end adapted for introduction into the gaseous medium.

A method according to claim 1, wherein the apparatus further comprises at least on connecting means for connecting the apparatus to a gas source.

A method according to claim 2, wherein the access port has connecting means for connecting the apparatus to a gas source.

A method according to claim 1, wherein the separate blow back means is positioned in one of the walls embracing a chamber on the outside of the filter.

A method according to claim 1, wherein the access port and one of the walls embracing the chamber on the outside of the filter has means for connecting the apparatus to a gas source.

A method according to claim 1, wherein the pipe has at least one cavity adapted to receive a cooling liquid.

An apparatus for taking samples of a gaseous medium containing solid particles, said apparatus comprising a pipe having one end adapted for introduction into said gaseous medium, a tubular filter for filtering off the solid particles, said filter being positioned coaxially with the pipe and communicating with the interior of the pipe, a removable closure being positioned on the downstream side of the tubular filter and coaxially with the pipe and withdrawal means for withdrawing the filtered gaseous medium from the outer side of the tubular filter, the apparatus wherein it further comprises a separate inlet for cleaning gas, said separate inlet being in communication with the outer side of the tubular filter.