摘要:
The invention includes a process and apparatus for separating a liquefied natural gas (LNG) stream containing methane and lighter components and heavy hydrocarbon components into a more volatile gas fraction containing a substantial amount of the methane and lighter components and a less volatile fraction containing a large portion of the heavy hydrocarbon components. The process includes splitting the LNG stream, preheating and providing to a fractionation tower at two locations. A tower reflux stream is utilized.
摘要:
The invention includes a process and apparatus for separating a liquefied natural gas (LNG) stream containing methane and lighter components and heavy hydrocarbon components into a more volatile gas fraction containing a substantial amount of the methane and lighter components and a less volatile fraction containing a large portion of the heavy hydrocarbon components. The process includes splitting the LNG stream into two feed streams, preheating the resulting first feed stream and providing the feed stream to a fractionation tower at two locations.
摘要:
Feed gas (1) in an improved NGL processing plant is cooled below ambient temperature and above hydrate point of the feed gas to condense heavy components (6) and a significant portion of water (4) contained in the feed gas. The water (4) is removed in a feed gas separator (101) and the condensed liquids are fed into an integrated refluxed stripper (104) that operates as a drier/demethanizer for the condensed liquids, and the uncondensed portion (5) containing light components is further dried (106) and cooled prior to turboexpansion (23) and demethanization (112). Consequently, processing of heavy components in the cold section is eliminated, and feed gas with a wide range of compositions can be efficiently processed for high NGL recovery at substantially the same operating conditions and optimum expander efficiency.
摘要:
An improved apparatus and method for providing reflux to a refluxed heavies removal column of a LNG facility. The apparatus comprises stacked vertical core-in-kettle heat exchangers and an economizer disposed between the heat exchangers. The reflux stream originates from the methane-rich refrigerant of the methane refrigeration cycle. The liquid reflux stream generated by cooling the methane-rich stream in the vertical heat exchangers via indirect heat exchange with an upstream refrigerant.
摘要:
A process for the extraction and recovery of ethane and heavier hydrocarbons (C2+) from LNG. The process covered by this patent maximizes the utilization of the beneficial cryogenic thermal properties of the LNG to extract and recover C2+ form the LNG using a unique arrangement of heat exchange equipment, a cryogenic fractionation column and processing parameters that essentially eliminates (or greatly reduces) the need for gas compression equipment minimizing capital cost, fuel consumption and electrical power requirements. This invention may be used for one or more of the following purposes: to condition LNG so that send-out gas delivered from an LNG receiving and regasification terminal meets commercial natural gas quality specifications; to condition LNG to make Lean LNG that meets fuel quality specifications and standards required by LNG powered vehicles and other LNG fueled equipment; to condition LNG to make Lean LNG so that it can be used to make CNG meeting specifications and standards for commercial CNG fuel; to recover ethane, propane and/or other hydrocarbons heavier then methane from LNG for revenue enhancement, profit or other commercial reasons.
摘要:
Natural gas liquefaction system employing a turboexpander to convert excess pressure within a predominantly methane stream into work useable in another location within the liquefaction system. Primarily, the turboexpander is used to compress a refrigerant used in at least one of the refrigeration cycles within the liquefaction system.
摘要:
A natural gas liquid plant includes a separator (103) that receives a cooled low pressure feed gas (4), wherein the separator (103) is coupled to an absorber (108) and a demethanizer (110). Refrigeration duty of the absorber (108) and demethanizer (110) are provided at least in part by expansion of a liquid portion of the cooled low pressure feed gas (4) and an expansion of a liquid absorber bottom product (19), wherein ethane recovery is at least 85 mol % and propane recovery is at least 99 mol %. Contemplated configurations are especially advantageous as upgrades to existing plants with low pressure feed gas where high ethane recovery is desirable.
摘要:
A process and apparatus for controlling or reducing the heating value or BTU content of NGL recovered from LNG streams. LNG pipelines have a maximum allowable heating value that LNG must be within prior to entering the pipeline. If the LNG heating value is too high, the components contributing to the high heating value must be removed prior to being introduced in the pipeline. The process controls the heating value of the residue LNG gas stream by splitting a feed stream and warming at least a portion of the feed stream. Substantial differences in enthalpy content and temperature between the two portions of the feed stream exist prior to being sent to a fractionation tower.
摘要:
A process and apparatus for the recovery of ethane and heavier components from a hydrocarbon feed gas stream. Feed gas stream is cooled and separated into a vapor stream and a condensed stream. Vapor stream is divided into a first and a second gas streams. First gas stream is expanded and sent to a fractionation tower. Second gas stream is supplied to an absorber tower. At least a part of the first liquid stream is cooled and sent to the absorber. Absorber column produces a lean vapor stream and a second condensed stream. Lean vapor stream is cooled and sent to the fractionation tower. Second condensed stream is subcooled and supplied to the fractionation tower. Temperatures and pressures of the streams and columns are maintained to recover a major portion of ethane and heavier hydrocarbon components as bottom product, and produce at the fractionation tower overhead, a residue gas stream.
摘要:
A process for the recovery of natural gas liquids (NGL) (ethane, ethylene, propane, propylene and heavier hydrocarbons) from liquefied natural gas (LNG) is disclosed. The LNG feed stream is split with at least one portion used as an external reflux, without prior treatment, to improve the separation and recovery of the natural gas liquids (NGL).