Peatlands cover only 2.84% of the land surface of the planet, yet they provide the human population with a wide range of services, including more than a third of soil carbon storage, river flow regulation, and biodiversity (Xu et al., 2018). These sensitive systems require high precipitation or impeded drainage to develop and remain stable. Industrialization, mechanization, land-use change (e.g., agriculture or forestry) and extraction of peat for horticultural and energy production have all led to degradation of peatlands.Blanket peat, the dominant UK peat type, is unusual among peatlands in that it occurs on slopes up to 15° (Lindsay et al., 1988). When surface vegetation is damaged, their sloping nature means that erosion can rapidly occur (Evans, Allott, et al., 2005;Evans, Warburton, & Yang, 2006). Rapid and extensive peatland degradation has been going on in the UK uplands for at least a century due to increased atmospheric pollution (e.g., Rothwell et al., 2007), drainage, grazing, and wildfire damage (e.g., Evans &Warburton, 2011). Peatland degradation not only poses a severe threat to an important ecosystem, but in some circumstances may also enhance downstream flood risk (Acreman & Holden, 2013). For peat to develop and persist it must be largely saturated for much of the year, thus even intact blanket peatlands are often able to store little water during rainfall events, relative to other landscapes. Blanket peatlands typically exhibit a flashy response to rainfall, dominated by saturation-excess overland flow and/or near surface throughflow with minimal base-flow contribution (Evans, Burt, et al., 1999). Peatland degradation through, for instance, vegetation

Numerical simulation of compositional flow problems commonly involves the use of 1st-or 2nd-order Euler time stepping. Method of lines (MOL), using highly accurate and efficient ODE solvers, is an alternative technique which, although frequently applied to the solution of two-phase, two-component flow problems, has generally been overlooked for problems concerning more than two components. This article presents the development of a numerical simulator for 1D, compressible, two-phase, three-component, radially symmetric flow using the method of lines (MOL) and a 3rd-order accurate spatial discretization using a weighted essentially non-oscillatory (WENO) scheme. The MOL implementation enables application of the MATLAB ODE solver, ODE15s, for time integration. Simulation examples are presented in the context of CO 2 injection into a reservoir containing a mixture of CH 4 and H 2 O. Following an assumption of constant equilibrium ratios for CO 2 and CH 4 , a ternary flash calculator is developed providing closed-form relationships for exact interpolation between equations of state for CO 2 -H 2 O and CH 4 -H 2 O binary mixtures. The numerical code is successfully tested and verified for a range of scenarios by comparison with an existing analytical solution.

Peatlands cover only 2.84% of the land surface of the planet, yet they provide the human population with a wide range of services, including more than a third of soil carbon storage, river flow regulation, and biodiversity (Xu et al., 2018). These sensitive systems require high precipitation or impeded drainage to develop and remain stable. Industrialization, mechanization, land-use change (e.g., agriculture or forestry) and extraction of peat for horticultural and energy production have all led to degradation of peatlands.Blanket peat, the dominant UK peat type, is unusual among peatlands in that it occurs on slopes up to 15° (Lindsay et al., 1988). When surface vegetation is damaged, their sloping nature means that erosion can rapidly occur (Evans, Allott, et al., 2005;Evans, Warburton, & Yang, 2006). Rapid and extensive peatland degradation has been going on in the UK uplands for at least a century due to increased atmospheric pollution (e.g., Rothwell et al., 2007), drainage, grazing, and wildfire damage (e.g., Evans &Warburton, 2011). Peatland degradation not only poses a severe threat to an important ecosystem, but in some circumstances may also enhance downstream flood risk (Acreman & Holden, 2013). For peat to develop and persist it must be largely saturated for much of the year, thus even intact blanket peatlands are often able to store little water during rainfall events, relative to other landscapes. Blanket peatlands typically exhibit a flashy response to rainfall, dominated by saturation-excess overland flow and/or near surface throughflow with minimal base-flow contribution (Evans, Burt, et al., 1999). Peatland degradation through, for instance, vegetation

In 2015, the North Sea petroleum province was 50 years old. The celebrations were short lived because oil prices and gas prices were in free fall. The demand from the UK market had outstripped demand back in 2005 and, 10 years on, falling production and increasing operating expenditure, when coupled with falling prices, had brought the North Sea to crisis point. Many fields became unprofitable and companies began to close down. In an effort to avert the developing crisis, this work examines what options exist for better utilizing the North Sea industry, be that monetizing co-produced fluids or using the pore space once occupied by petroleum for waste products such as carbon dioxide. We briefly examine: the possibility of utilizing heat from the co-produced fluids for power generation; extracting gases and ores from co-produced fluids; and evaluation of the role that carbon dioxide could play in enhanced oil and gas recovery, as well as its ultimate long-term storage in geological deep storage.