Method of operating a fixed-bed gasifier for producing a product gas from pourable carbonaceous particles

A method of operating a fixed-bed gasifier for producing a product gas from a bed of fuel particles, the method comprising the steps of:

• positioning at least one tapping element at a first point above the bed of fuel particles;
• lowering the at least one tapping element into the bed of fuel particles along a first linear path to form a first linear passage in the bed of fuel particles;
• raising the at least one tapping element to retract the at least one tapping element from the bed of fuel particles along the first linear path so that the at least one tapping element exits the bed of fuel particles from the first linear passage;
• positioning the at least one tapping element at a second point above the bed of fuel particles;
• lowering the at least one tapping element into the bed of fuel particles along a second linear path to form a second linear passage in the bed of fuel particles;
• and
• raising the at least one tapping element to retract the at least one tapping element from the bed of fuel particles along the second linear path so that the at least one tapping element exits the bed of fuel particles from the second linear passage
• the at least one tapping element being lowered and raised to minimize disturbance of fuel particles around the first linear passage and the second linear passage.