Pipeline-quality gas

Selexol. licensed by the Norton Company, uses the dimethyl ether of polyethylene glycol. A Selexol plant can be designed to provide some selectivity for H2S. For example, the plant can be designed to provide pipeline quality gas (0.25 grains H S/IOOscf) while slipping 85% of the COi. ... 

In the solution, the amine DIPA is meanwhile able to achieve pipeline quality gas (0.25 grains IT/lOOscf). 

This process uses propylene carbonate as a physical solvent to remove CO2 and H2S. Propylene carbonate also removes C2+ hydrocarbons, COS, SO2, CS2, and H2O from the natural gas stream. Thus, in one step the natural gas can be sweetened and dehydrated to pipeline quality. In general, this process is used for bulk removal of CO2 and is not used to treat to less than 3% CO2, as may be required for pipeline quality gas. The system requires special design features, larger absorbers, and higher circulation rates to obtain pipeline quality and usually is not economically applicable for these outlet requirements. 

Another problem is when the carbon dioxide content of natural gas is too high and must be lowered to produce pipeline-quality gas. Although the current practice is to vent this CO, sequestration of CO, in underground geologic formations is being considered. Already, in the Norwegian sector of the North Sea, CO, has been injected into saline aquifers at a rate of 1 million tons a year to avoid... 

D. Blum Just going a bit further, the liquid-phase methanation process now uses one reactor. You can or you cannot use a polishing reactor as the economics dictate. You can actually go right to pipeline quality gas in one reactor, which is equivalent to about 99.8% conversion of a 20% CO feed gas. We envision at this moment that combined shift-methanation could be done in the same single reactor. It would obviously require lower feed gas rates so you may need two of these reactors. We don t exactly have the numbers yet. I think that s one of the areas that deserves future work. 

The initial biogas recovered is an MHV gas and is often upgraded to high heat value (HHV) gas when used for blending with natural gas supplies. The annual production of HHV gas in 1987, produced by 11 HHV gasification facilities, was 116 x 106 m3 of pipeline-quality gas, ie, 0.004 EJ (121). This is an increase from the 1980 production of 11.3 x 106 m3. Another 38 landfill gas recovery plants produced an estimated 218 x 106 m3 of MHV gas, ie, 0.005 EJ. Additions to production can be expected because of landfill recovery sites that have been identified as suitable for methane recovery. In 1988, there were 51 sites in preliminary evaluation and 42 sites were proposed as potential sites (121). 

High Heat- Value Gas. High heat-value (high Btu) gas (7) has a heating value usually in excess of 33.5 MJ/m3 (900 Btu/ft3). This is the gaseous fuel that is often referred to as substitute or synthetic natural gas (SNG), or pipeline-quality gas. It consists predominantly of methane and is compatible with natural gas insofar as it may be mixed with, or substituted for, natural gas. 

Cost-of-service tariff for sale of pipeline quality gas by the partnership to pipeline members. 

The transmission function covers transport of the processed pipeline quality gas from the gas-processing plant to major markets. About two-thirds of U.S. marketed gas production reaches the ultimate consumer through a network of some 250,000 miles of pipelines. Other deliveries may be made directly to industrial consumers or to city distribution systems. 

Gas from Coal. Progress toward the development of improved processes to produce high-Btu, synthetic pipeline-quality gas from coal can currently be seen on several fronts. Two large-scale coal gasification pilot plants are currently in operation or under construction and plans to build two others are advancing. The pilot plant in operation is located... 

With these factors in mind, the availability of pipeline-quality gas from coal may be projected to rise from about 0.1 Tcf in 1976 to 0.3 Tcf annually by 1980, with these volumes most likely entirely attributable to Lurgi-type plants. Gas available from added facilities based on the newer process technologies currently under development is projected to bring the total annual volumes of gas available from coal gasification to about 1.4 and 3.3 Tcf, respectively, in 1985 and 1990. 

The number of trim-methanation stages required depends on the final product specifications. Generally, two trim-methanation stages are sufficient to produce a high-methane, pipeline-quality gas. 

Dehydration and carbon dioxide removal to produce 4X10° cu ft/day of pipeline quality gas for sale to Southern California Gas Company for blending into pipeline. 

Synthetic (substitute) natural gas Pipeline-quality gas that is interchangeable with natural gas (mainly methane). 

Figure 1 Operations included within the system boundary for the shale gas life cycle. GHG emissions and freshwater consumption associated with operations up to and including gas treatment and processing are allocated to pipeline quality gas (which goes on to the transmission pipeUne) and the natural gas liquid (NGL) coproduct in accordance with their heat content (HHV) transportation, fractionation and disposition of NGL are not included within the scope of this study. GHG emissions and freshwater consumption associated with power distribution are also excluded from the scope of this study.

Pipeline Quality Gas Use as vehicle fuel Incorporation into local natural gas pipeline... 

Gas purification to pipeline quality is yet another option. This option involves the conversion of landfill a medium heating value gas, into high heating value gas for local gas distribution networks (h, in compressed form, for vehicular fuel. In 1992, there were 7 sites that upgraded landfill gas to pipeline-quality gas. This option also remains uneconomical as Icmg as the prices of natural gas and fuel oil remain relatively low [16]. 

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