Evaluation of the Exxon CFZ and CNG-Claus process for the treatment of subquality natural gas. Final report, May-November 1991

Technical Report · Fri Jun 26 00:00:00 EDT 1992

OSTI ID:7195156

Cole, E T; Valencia, J A; Cook, W J; Siwajek, L A; Brown, W R

Vast quantities of subquality natural gas exist which are unsuitable for conventional gas treating. The CFZ technology developed by Exxon Production Research and the TPC technology developed by CNG Research Company can be integrated to process subquality natural gas. These low temperature processes can produce pipeline spec natural gas from subquality gas containing more than 10% carbon dioxide and any amount of hydrogen sulfide. The CO2 can be separated as a high pressure stream suitable for re-injection, reducing CO2 emissions to the atmosphere, or as high purity CO2 for commercial applications. Two cases are examined at a scale of 20 MMSCFD: an Exxon gas with 66% carbon dioxide, 20% methane, and a GRI generic gas with 18% carbon dioxide, 80% methane. Process flow diagrams and economics are developed. Breakeven allowances for raw gas cost are established, i.e., the raw gas cost at which plant net revenues would be zero. Breakeven allowances range from ($0.34) to $1.79/MSCF of raw gas for low-high product price scenarios and a simple five year capital payback period. The results indicate that 20 MMSCFD is too restrictive a scale for widespread application of the technology. Economies of scale realized for raw gas flows greater than 100 MMSCFD allow a much broader application of the integrated technology. Simple extrapolation of economics to 250 MMSCFD yield breakeven allowances of $0.30 to $2.18/MSCF raw gas. The process achieves virtually 100% sulfur recovery at costs competitive with conventional Claus plus tail gas processes.

• Research Organization: Exxon Production Research Co., Houston, TX (United States)
• OSTI ID: 7195156
• Report Number(s): PB-92-238815/XAB; CNN: GRI-5090-222-2011
• Resource Relation: Other Information: Prepared in cooperation with Sweetland Engineering and Associates, Inc., State College, PA., and CNG Research Co., Pittsburgh, PA. Sponsored by Gas Research Inst., Chicago, IL
• Country of Publication: United States
• Language: English

Related Subjects

03 NATURAL GAS
CARBON DIOXIDE
MATERIALS RECOVERY
NATURAL GAS
SEPARATION PROCESSES
SULFUR
CLAUS PROCESS
COST
CRYSTALLIZATION
ECONOMIC ANALYSIS
FLOW RATE
FLOWSHEETS
GAS FLOW
METHANE
NATURAL GAS PROCESSING PLANTS
QUANTITY RATIO
ALKANES
CARBON COMPOUNDS
CARBON OXIDES
CHALCOGENIDES
DIAGRAMS
ECONOMICS
ELEMENTS
ENERGY SOURCES
FLUID FLOW
FLUIDS
FOSSIL FUELS
FUEL GAS
FUELS
GAS FUELS
GASES
HYDROCARBONS
INDUSTRIAL PLANTS
MANAGEMENT
NONMETALS
ORGANIC COMPOUNDS
OXIDES
OXYGEN COMPOUNDS
PHASE TRANSFORMATIONS
PROCESSING
WASTE MANAGEMENT
WASTE PROCESSING
030300* - Natural Gas- Drilling
Production
& Processing