“Wellbore Integrity…” Say What

摘要

Convincing people to try something new, strange and expensive is not easy. Convincing them to embrace something that they fear and struggle to understand is almost impossible. Many people seem to fear CO_2 Capture and Storage (CCS) and remain skeptical that it will evolve into a huge opportunity to control global CO_2 emissions. It needs to be explained in terms normal people understand. Not everyone speaks the same language or starts from the same point of reference. This effort is by a high school junior using common language and images familiar to me and my friends to visualize basic science relationships related to the storage part of CCS: soccer balls and playing fields. It considers key components of well systems and makes comparisons with the behavior of natural phenomena like ant hills enduring in a light rain storm, and compares that with their fate when attacked by a little brother with a water hose. It asks questions about the dimensions of the systems, and how key components might work. It's about putting CO_2 underground, but how do you explain that with soccer balls? Instinctively, the big question is will the CO_2 stay underground? What will happen to it with time? Why won't it just come right back out a well like a straw? What about all those wells anyway? Should people get hyped-up about them? Aren't they filled with cement? Think, CO_2 in water makes an acid. What will that acid do? Is it about pumping and sucking fluids thru barriers as strong as steel instead of allowing them to flow freely in a hose? Stay tuned and read on. Full disclosure: This paper is not exactly cutting edge science; it offers no new data, and tests no hypothesis although it makes some original calculations. It's about communication and visualization, so it deliberately dodges some important details about well construction techniques, reaction rates, kinetics and the multiphase behavior of supercritical CO_2, even in the same reservoir. It touches on fundamentals of reservoir porosity and permeability, and even subsurface fluid flow but just barely. Just enough to be cool, stressed, over pressured and dense phased, more or less like the injected gas we care so much about.