HSE & Sustainability

In-Situ Hydrogen Production From Natural Gas Wells With Subsurface Carbon Retention

To meet the objective of balancing economic prosperity, energy security, and environmental protection, a natural gas gasification process within a downhole completion tool is proposed that converts methane wells into hydrogen production wells, while simultaneously capturing the process-generated carbon downhole and reinjecting the carbon dioxide into the surrounding geology.

Blue air bubbles rising to the surface
Source: Constantin Cornel/Getty Images

There is a critical need to balance economic prosperity, energy security, and environmental protection. Instead of the conventional production of methane (or CH4), these valuable energy reserves can be exploited in a climate-beneficial way. Exploiting (not producing) methane eliminates the carbon value chain and the associated damage these greenhouse gases cause to the climate. When no carbon is produced to the surface, carbon capture requirements become significantly reduced, and their huge budgets are better used elsewhere.

This paper discusses the viability of a wellbore natural gas gasification process, within a downhole completion tool, that converts methane wells into hydrogen (or H2) production wells. The process-generated carbon is simultaneously captured downhole, reinjecting the carbon dioxide (or CO2) into the surrounding geology and potentially gaining reservoir enhanced oil recovery as a bonus. The proposed process is for natural gas fields and not for use in the gasification of heavy oils (which is covered by other “combustion type” reservoir management processes performed deep within the reservoir geology).

The multiple revenue streams created by the process, together with process energy, feedstock (methane), and cost savings, make it climate-positive and financially viable. This provides a net-zero win-win that is mutually beneficial for the natural gas industry and the environment. Without enormous technical effort, competitive use of commodities, and huge capital costs, it could be possible to convert the natural gas industry directly into a hydrogen and carbon capture industry.

This abstract is taken from paper SPE 219449 by S. R. Gillick, Metharc ApS, and M. Babaei, University of Manchester. The paper has been peer reviewed and is available as Open Access in SPE Journal on OnePetro.