Energy recovery turbocharger with integral motor/generator

An energy recovery turbocharger configured to pressurize a reactant fluid for delivery to a pressurized process, and to recover energy from a pressurized product fluid received from the pressurized process, the turbocharger comprising:

• a pump comprising an impeller fixed to an impeller shaft, the pump being configured to deliver the reactant fluid to the pressurized process at a required reactant pressure by rotating the impeller at a required impeller rate;
• a turbine comprising a runner fixed to a runner shaft, the runner shaft being mechanically coupled to the impeller shaft, so that rotation of the runner at a runner rotation rate necessitates rotation of the impeller shaft at a proportionate impeller rotation rate, and so that rotation of the impeller shaft at the proportionate impeller rotation rate necessitates rotation of the runner at the runner rotation rate, the turbine being configured to apply a torque to the impeller according to an impact upon the runner by the pressurized product fluid;
• a variable speed motor/generator mechanically cooperative with at least one of the impeller, the impeller shaft, the runner, and the runner shaft, the motor/generator being configured to impart additional torque to the impeller by receiving supplemental electrical energy from a power grid, and to withdraw excess torque from the impeller by generating excess electrical energy and delivering the excess electrical energy to the power grid;
• a plurality of guide vanes configured to accelerate the pressurized product fluid as the pressurized product fluid enters the turbine, and before the pressurized product fluid impacts the runner, a pitch of the guide vanes being variable;
• and
• a controller configured to control the impeller rotation rate such that the impeller rotation rate is equal to the required impeller rotation rate, thereby ensuring that the reactant fluid is supplied to the pressurized process at the required reactant pressure, without causing a bypass valve or a throttle valve to modify a flow of the pressurized product fluid to the turbocharger, said controlling of the impeller rotation rate comprising controlling by the controller of the supplemental electrical energy received by the motor/generator from the power grid and controlling by the controller of the excess electrical energy generated by the motor/generator and delivered to the power grid;
• the controller being further configured to adjust the pitch of the guide vanes such that an energy efficiency of the turbine is optimized when the runner rotates at the runner rotation rate that is necessitated by rotation of the impeller at the required impeller rotation rate.