System and method for separation and control of entrained gas mixture

1. A power generation system, comprising:

a gas turbine for generating power;

a gasifier for generating gaseous fuel;

a gas combustor configured to receive a combination of steam and the fuel to power the gas turbine;

a manifold section, including a manifold drain, configured to provide the combination of steam and the fuel to the gas combustor; and

a drain collection and separation system configured to (i) collect a portion of the steam which has entered into the manifold as a condensed liquid and a portion of the gaseous fuel entrained in the liquid, and (ii) separate the entrained gaseous fuel from the liquid so the separated gaseous fuel can be cycled or disposed of separately from liquid, the drain collection and separation system including a liquid-gas separation tank and a drain line connecting the manifold drain to the liquid-gas separation tank so that the liquid-gas separation tank receives the condensed liquid with entrained gaseous fuel from the manifold, and wherein separation of the entrained gaseous fuel from the liquid occurs in the liquid-gas separation tank based on movement of the liquid along a wall of the tank.

2. The system of claim 1 wherein the gaseous fuel is syngas.

3. The system of claim 1 wherein the gaseous fuel and steam are combined in a fuel line.

4. The system of claim 1 wherein the liquid-gas separation tank includes a cylindrical-shaped wall portion, and the drain collection and separation system is configured to introduce the condensed liquid with entrained gaseous fuel received from the manifold in a tangential manner along the cylindrical-shaped wall portion, whereby circular motion along the cylindrical-shaped wall portion facilitates separation of relatively heavy material of the condensed liquid from relatively light gaseous fuel entrained therein.

5. The system of claim 4 wherein the drain collection and separation system collects mixtures of liquid and gas from multiple sources, and combines the mixtures in the tank for separation of entrained gases to allow gas flow from the tank separate from liquid flow out of the tank.

6. A drain collection and separation system for a power generation system including a gas combustor configured to receive fuel from a manifold to power a gas turbine, comprising:

a plurality of condensate drain lines and a liquid separation tank, the plurality of drain lines positioned to receive a mixture comprising liquid and gas from at least one source in the power generation system and for routing the mixture to the liquid-gas separation tank, at least one of the drain lines connected to receive condensate comprising condensed steam and gaseous fuel entrained therein from the manifold; and

a gas dilution system positioned to inject additional gas to the mixture, wherein the liquid-gas separation tank is configured, based on movement of the liquid along a wall of the tank, to separate gas in the mixture from liquid in the mixture and move gas out of the tank separate from movement of liquid out of the tank.

7. The system of claim 6 further including a control system and a plurality of valves to control flow of the mixture and effect receipt and separation of the mixture.

8. The system of 6 including a drain pot positioned between the at least one source and the tank to receive the mixture, wherein movement of the mixture in and out of the drain pot is controllable with a pair of level switches which set a maximum and a minimum liquid level in the pot.

9. The system of 7 wherein the control system receives control signals from a plurality of level switches, a pressure transmitter, and an oxygen sensor, and controls the positions of valves to effect the collection and separation of liquid and gas in the mixture.