NGL Recovery Methods and Configurations
First Claim
Patent Images
1. A plant comprising:
- a feed gas separator that is configured to separate a feed gas into a liquid portion and a vapor portion;
a demethanizer fluidly coupled to the separator and configured to receive the vapor portion and the liquid portion;
a turboexpander configured to receive and expand at least part of the vapor portion in a location upstream of the demethanizer; and
a feed gas bypass circuit that is configured to provide part of the feed gas as a bypass gas to the vapor portion upstream of the demethanizer in an amount sufficient to prevent carbon dioxide freezing in the demethanizer and to reduce carbon dioxide content in a demethanizer bottom product.
1 Assignment
0 Petitions
Accused Products
Abstract
Contemplated NGL plants include a feed gas bypass circuit through which a portion of the feed gas is provided downstream to a vapor portion of the feed gas to thereby increase turbo expander inlet temperature and demethanizer temperature. Contemplated configurations are especially advantageous for feed gases with relatively high carbon dioxide content as they entirely avoid carbon dioxide freezing in the demethanizer, provide additional power production by the turboexpander, and recover C2+ components to levels of at least 80% while achieving a low carbon dioxide content in the NGL product.
-
Citations
20 Claims
-
1. A plant comprising:
-
a feed gas separator that is configured to separate a feed gas into a liquid portion and a vapor portion; a demethanizer fluidly coupled to the separator and configured to receive the vapor portion and the liquid portion; a turboexpander configured to receive and expand at least part of the vapor portion in a location upstream of the demethanizer; and a feed gas bypass circuit that is configured to provide part of the feed gas as a bypass gas to the vapor portion upstream of the demethanizer in an amount sufficient to prevent carbon dioxide freezing in the demethanizer and to reduce carbon dioxide content in a demethanizer bottom product. - View Dependent Claims (2, 3, 4, 5, 6)
-
-
7. A control device, comprising:
-
a processing unit electronically coupled to a plurality of temperature sensors and a flow control valve; wherein the plurality of temperature sensors are thermally coupled to at least one of a feed gas stream, a bypass gas stream, a vapor stream of a feed gas separator, and a demethanizer; wherein the flow control valve is coupled to a feed gas bypass circuit that fluidly couples the feed gas stream with a vapor stream in or downstream from the feed gas separator; and wherein the processing unit is configured such that, using the flow control valve, a flow rate of the feed gas through the bypass circuit is a function of a temperature in at least one of the demethanizer and the bypass gas stream. - View Dependent Claims (8, 9, 10, 11, 12)
-
-
13. A method of separating a feed gas, comprising:
-
providing a feed gas, and separating a first portion of the feed gas into a vapor portion and a liquid portion; expanding part of the vapor portion in a turboexpander, and feeding the expanded part of the vapor portion into a demethanizer; combining a second portion of the feed gas with the vapor portion upstream of the demethanizer in an amount sufficient to eliminate carbon dioxide freezing in the demethanizer. - View Dependent Claims (14, 15, 16, 17, 18, 19, 20)
-
Specification