Method of treating flowback fluid

1. A method of treating a flowback fluid during a flowback stage of a well operation, comprising:

introducing the flowback fluid into a first stage vertical separator to produce a first gas stream, a liquid stream, and a solids stream;

passing the first gas stream from the first stage vertical separator to a sales gas line;

passing the liquid stream from the first stage vertical separator to a second stage horizontal separator with the pressure in the second stage horizontal separator being less than the pressure in the first stage vertical separator but greater than atmospheric pressure to produce a second gas stream, a water stream; and a liquid hydrocarbon stream;

passing the second gas stream from the second stage horizontal separator to a combustor or flare nozzle;

passing the water stream from the second stage horizontal separator to a water storage tank; and

passing the liquid hydrocarbon stream from the second stage horizontal separator to a liquid hydrocarbon storage tank.

2. The method of claim 1 , further comprising the step of passing the solids stream from the first stage vertical separator to the second stage horizontal separator.

3. The method of claim 1 , wherein the second stage separator has a liquid handling capability of about 4,500 barrels per day with a retention time of about 60 minutes.

4. The method of claim 1 , wherein the second stage separator has a liquid handling capability of about 9,000 barrels per day with a retention time of about 30 minutes.

5. The method of claim 1 , wherein the first stage separator has a liquid capacity of about 900 barrels per day with a retention time of between about 3 minutes and about 5 minutes.

6. The method of claim 5 , wherein the first stage separator has a gas capacity of about 5 million standard cubic feet per day.