Patent ID: 8460413

Claim:
A carburetion system for low-Btu gas comprising: a zero pressure regulator connected to a low-Btu gas inlet line; a plurality of pressure-based air-gas mixers downstream of the zero pressure regulator, the plurality of pressure-based air-gas mixers each having an air inlet and a gas inlet, wherein the gas inlet cross-sectional area in each pressure-based air-gas mixer of the plurality of pressure-based air-gas mixers is at least equal to the air inlet cross-sectional area; wherein the plurality of air-gas mixers are connected in series, wherein the plurality of air-gas mixers are arranged with an air supply in series and a gas supply in parallel, and wherein the plurality of pressure-based air-gas mixers is configured to provide a fuel having a volumetric air to gas ratio of no more than about 2:1; and a gas outlet upstream of the zero pressure regulator and connected with the low-Btu gas inlet line such that low-Btu gas can be diverted to the gas outlet, the zero pressure regulator or both.