Apparatus and method for three-phase separation at a well

A separator for separating one or more of liquid, oil, gas, and debris from a fluid produced from a wellbore, the separator comprising:

• a vessel defining an interior chamber;
• an inlet fluidly coupled with the wellbore to deliver the fluid produced from the wellbore into the vessel at a first pressure;
• an outlet to direct the gas out of the vessel at a pressure substantially equal to the first pressure;
• at least one liquid/oil level sensor to detect a level of the liquid within the interior chamber of the vessel and a level of the oil within the interior chamber;
• a first electronically controlled valve in fluid communication with the vessel;
• a second electronically controlled valve in fluid communication with the vessel;
• and
• a controller connected to the at least one liquid/oil level sensor and the first and second electronically controlled valves and programmed to, in response to the level of the liquid in the interior chamber of the vessel and the level of the oil in the interior chamber of the vessel detected by the at least one liquid/oil level sensor:
• open, close, or modulate the first electronically controlled valve to regulate a combined flow of the liquid and debris out of the vessel;
• and
• open, close, or modulate the second electronically controlled valve to regulate the flow of the oil out of the vessel;
• wherein the separation of the one or more of liquid, oil, gas, and debris occurs at a pressure substantially equal to the first pressure within the interior chamber, the first pressure being an unregulated pressure of the fluid flowing from the wellbore and of at least 1,500 psig.