(249o) Recovery of Natural Gas from Marginal Wells with a Deep Well Reactor

With the recent surge in availability, natural gas (methane) has become an important feedstock for the energy and chemicals market. Yet the low energy density and high compression cost necessitate high flow rates close to market for economic viability. Subsequently, a significant quantity of gas remains in the ground in ‘abandoned wells,’ once the well has hit the economic threshold. Furthermore, ‘remote wells,’ cannot be tapped because the cost of liquefaction and transportation are cost prohibitive. Similarly, oil-associated gas is flared in preference to the more desirable oil, wasting energy and opportunity. Technologies with low capital cost and low complexity could be leveraged to monetize low flow rate and low pressure natural gas. Currently, all gas-to-liquid technologies (e.g. Fischer-Tropsch Synthesis) are incredibly capital-intensive and only economically viable at very large scales. A new low-capital paradigm is required to tap the gas available only at low flow rate and pressure. Here we present a mathematical model of one such possibility that we term the ‘Deep Well Reactor,’ which utilizes pre-existing structures for the biological conversion of methane to liquid fuels and chemicals. One of the major issues is cost-effective mass transfer of the methane to the reactive phase. We show that this technology can effectively overcome these limitations without any extra complexity. Furthermore, we stipulate minimum conversion rates that would be required for a feasible process with biological or inorganic catalysts.