Gaz analyzer with protection for optical components

A gas analyzer for optical In Situ measurements of process gas including dust and other particulates, the gas analyzer comprising:

• a pipe;
• a measurement chamber for measurement of process gas in a center of the pipe;
• and
• optical components at each longitudinal end of the pipe, wherein
• the pipe comprises a filter wall separating surrounding process gas from the measurement chamber such that the dust and other particulates are left out as process gas without particulates moves to the measurement chamber;
• a purging chamber comprising a gas inlet positioned on both longitudinal sides between the optical components and a suction chamber prepared for producing a gas cushion with a clean gas, for protecting the optical components from corrosive components in the process gas without particulates;
• a suction chamber for producing a suction scheme for the clean gas from the purging chamber and the process gas without particulates from the measurement chamber forming in the suction chamber a gas mix preventing the clean gas from entering the measurement chamber;
• the suction chamber comprising gas outlet being positioned between the purging chamber and the measurement chamber for producing a suction scheme for preventing the clean gas from entering the measurement chamber;
• and
• a controller controlling flow of gas through the inlets and the outlets, wherein the pressure of gas media is used as inputs to the controller.