NOVELTY - A gas distributor for a stacked particle bioreactor which produces synfuels from biodegradable carbonaceous material comprises a pipe (1) having a series of apertures (3) through the wall of the pipe, where the apertures are configured to face downwards in a stacked particle bioreactor, and preferably located in an indentation (2) in the outer wall of the pipe.    USE - For a stacked particle bioreactor for producing synfuels from biodegradable carbonaceous material (claimed); and for producing ethanol, methane, and other hydrocarbon products.    ADVANTAGE - Since the pipe is of single length and it is simple laid with apertures face down onto a layer of material and can then be covered with more material, which is simpler, quicker, and cheaper than prior art gas distributor system. The gas distributor is single piece improved gas distributor and provides protection for the apertures from blocking by random alignment of carbonaceous material, which can occur during stacking of the bioreactor after placement of the pipe; and also provides protection for the apertures from precipitates forming in them as a result of evaporation of liquid draining through the stack which runs over the apertures or over material proximate the apertures.    DETAILED DESCRIPTION - A gas distributor for a stacked particle bioreactor which produces synfuels from biodegradable carbonaceous material comprises a pipe (1) having a series of apertures (3) through the wall of the pipe, where apertures are configured to face downwards in a stacked particle bioreactor, and preferably located in an indentation (2) in the outer wall of the pipe. The pipe includes continuous indentations or endless circumferential indentations. The endless circumferential indentation includes two apertures spaced apart by 0-45?oC from the vertical along the circumference of the pipe. The continuous indentation comprises a helical indentation. The gas distributor includes a perforated cover over each aperture. An INDEPENDENT CLAIM is included for forming a stacked particle bioreactor involving installing the gas distributor in the stacked particle bioreactor.    DESCRIPTION OF DRAWING(S) - The figures show perspective view of the gas distributor, and end view of the pipe, and bottom plan view of the pipe.    pipe (1)    indentation (2)    apertures (3)    bottom of pipe. (4)