A system for treating and conveying natural gas, comprising: - a supply circuit feeding energy-production equipment chosen from a combustion engine, a fuel cell or a gas turbine, allowing natural gas to be conveyed from a liquefied natural gas storage tank to said energy-production equipment (4, 6), said supply circuit comprising an upstream portion connected to the tank and a downstream portion connected to the energy-production equipment (4, 6); - a burner supply circuit allowing natural gas to be conveyed from the tank to the burner, comprising an upstream portion connected to the tank and a downstream portion connected to the burner; - a heating circuit for heating the tank able to collect a stream of gas at the bottom of the tank and inject it into the top of the tank, said heating circuit comprising an upstream portion connected to a pipeline opening into the bottom of the tank and a downstream portion connected to a pipeline opening into the top of the tank; in which: - the energy-production equipment supply circuit and the heating circuit comprise a circuit portion in common which comprises a compressor (16a, 16b) having an inlet and an outlet and allowing the pressure and temperature of a stream of gas to be increased, said portion in common being delimited, upstream, by a first switchable three-way connection member (50, 150, 170) allowing the upstream portion of the energy-production equipment supply circuit or the upstream portion of the heating circuit to be connected selectively to the inlet of the compressor (16a, 16b) and, downstream, by a second switchable three-way connection member (62, 162, 262; 63, 163, 263) allowing the outlet of the compressor to be connected selectively to the downstream portion of the energy-production equipment supply circuit or to the downstream portion of the heating circuit; - the downstream portion of the heating circuit comprising a third three-way connection member allowing said downstream portion of the heating circuit to be connected to the downstream portion of the supply circuit feeding the burner so as to remove part of the stream of gas conveyed in the heating circuit toward the burner. - a supply circuit feeding energy-production equipment chosen from a combustion engine, a fuel cell or a gas turbine, allowing natural gas to be conveyed from a liquefied natural gas storage tank to said energy-production equipment (4, 6), said supply circuit comprising an upstream portion connected to the tank and a downstream portion connected to the energy-production equipment (4, 6); - a burner supply circuit allowing natural gas to be conveyed from the tank to the burner, comprising an upstream portion connected to the tank and a downstream portion connected to the burner; - a heating circuit for heating the tank able to collect a stream of gas at the bottom of the tank and inject it into the top of the tank, said heating circuit comprising an upstream portion connected to a pipeline opening into the bottom of the tank and a downstream portion connected to a pipeline opening into the top of the tank; in which: - the energy-production equipment supply circuit and the heating circuit comprise a circuit portion in common which comprises a compressor (16a, 16b) having an inlet and an outlet and allowing the pressure and temperature of a stream of gas to be increased, said portion in common being delimited, upstream, by a first switchable three-way connection member (50, 150, 170) allowing the upstream portion of the energy-production equipment supply circuit or the upstream portion of the heating circuit to be connected selectively to the inlet of the compressor (16a, 16b) and, downstream, by a second switchable three-way connection member (62, 162, 262; 63, 163, 263) allowing the outlet of the compressor to be connected selectively to the downstream portion of the energy-production equipment supply circuit or to the downstream portion of the heating circuit; - the downstream portion of the heating circuit comprising a third three-way connection member allowing said downstream portion of the heating circuit to be connected to the downstream portion of the supply circuit feeding the burner so as to remove part of the stream of gas conveyed in the heating circuit toward the burner.