Shale Gas Techno-Economic Analysis: Designing Separation Units to Handle Feedstock Variability
Eric Bohac (1,2), Dr. Mahmoud El-Halwagi (1,2), Dr. Debalina Sengupta (1,2)
1. Texas A&M University, Chemical Engineering Department
2. TEES Gas and Fuels Research Center
Shale gas is abundant in the U.S. and this presents many opportunities in the chemical, petrochemical, and fuel industries. As with conventional natural gas, shale gas is primarily methane, but also may contain significant compositions of higher molecular weight hydrocarbons, and other impurities. This variability presents a technical challenge to processing the gas. There is a tradeoff between the size (and therefore cost) of processing units and the ability to handle a wider range of compositions. This research aims to find a design to optimize profitability based on processing differing raw shale gas compositions.
In this work a literature review of conventional and alternate technologies for processing shale gas was performed. Composition of the raw shale gas was based on literature data for wells in the Barnett Shale play located northwest of Dallas. Process simulators such as ProMax, ASPEN HYSYS, and ASPEN Plus were used to construct base-case scenarios, and to carry out process simulations for differing compositions with any necessary process modifications. A techno-economic analysis was done to estimate the associated costs and profitability of all the scenarios. Once this was done an optimal design was chosen and validated for a variety of compositions. Additionally a sensitivity analysis was done to see the effect of the various costs (fixed costs, variable costs, raw shale gas price, product prices) on profitability.
Keywords: Shale Gas, Process Simulation, Feedstock Variability