North American CCS projects – the good news and the bad news…
This reminds us of that old, familiar genre of ‘good news and bad news’ jokes – you know the format:
Doctor: “I have some good news and bad news.”
Patient: “Err, give me the good news first.”
Doctor: “You only have 24-Hours to live.”
Patient: “How is that good news? What’s the bad news then?”
Doctor: “I’ve been trying to call you since yesterday.”
Well, in this case the good news really is good. Unfortunately, the bad news is really bad.
The Quest CCS Project, Alberta, Canada
Shell’s Quest CCS Project, aimed at significantly reducing the ‘carbon footprint’ of their commercial Scotford oil sands upgrading facility at Fort Saskatchewan in Alberta, has proven very successful by capturing two million tonnes of carbon dioxide earlier this month, some three months ahead of schedule.
“This project has just been incredibly exciting because not only are we proving that this technology works, but we are demonstrating that Canadians are at the forefront of carbon capture and technology”, said Conal MacMillan, Shell Canada’s external relations advisor.
The Quest project – a fully-integrated CCS project being undertaken as a joint venture between Shell, Chevron and Marathon – was inaugurated in November 2015. 1.2 million tones of CO2 per annum is being captured from three steam methane reformers (SMRs) that are used to produce hydrogen for upgrading oil sand products, and representing around 35% of the Scotford upgraders’ direct CO2 emissions. The CO2 is captured upstream of the hydrogen purification unit (pressure swing absorption), where the raw process gas composition is typically 74% H2, 17% CO2, 6% CH4 and 3% CO on a volume basis, using the commercially-proven Shell ADIPX activated amine absorption post-combustion capture technology. The >99% pure CO2 is dried and (multi-stage) compressed to 14,500kPa before being transported in the dense phase by a 80km, 12-inch diameter pipeline (3Mtpa capacity) and injected 2.1km underground into a porous sandstone saline formation reservoir with multiple caprock and salt seal levels above it (part of Canada’s enormous Western Sedimentary Basin, which is estimated to have a total potential CO2 storage capacity of over 19,200Mt). An extensive programme of CO2 measurement, monitoring and verification (MMV) is being undertaken to provide assurance that the CO2 is permanently stored. Click here to view an excellent video of this CCS process.
This 10-year, CAN$1.35 billion project has been supported by both the Canadian and Alberta governments to the level of CAN$845 million.
The Kemper County Energy Facility Project, Mississippi, USA
US electric utility Southern Company’s commercial-scale integrated gasification combined cycle (IGCC) power plant and CCS demonstration project has suspended its gasifier operations this month, with the power generation switching to natural gas firing. This follows a decision of the Mississippi Public Service Commission to issue an order requiring the Kemper Facility to operate using only natural gas and requesting a “solution that eliminates ratepayer risk for unproven technology and assures no rate increase to… customers.” This decision follows many months of delays in becoming operational and considerable increases in the cost of the project.
The Kemper County IGCC+CCS project, which was to be operated by Mississippi Power (a subsidiary of Southern Company), was to have been a showcase of US-developed technology and a ‘flagship’ project of the US Department of Energy’s CCS programme, demonstrating large-scale integrated CCUS (carbon capture, utilisation and storage) through the ‘pre-combustion’ decarbonisation of lignite fuel (42-50% moisture content) at a mine-mouth facility, power generation via combustion of the resulting decarbonised synthesis gas (syngas), and transport of the separated CO2 for utilisation in enhanced oil recovery (EOR) operations. The IGCC plant comprises two TRIGTM transport gasifiers (a different approach to gasification from the normal entrained flow, slagging-mode gasifiers marketed by GE, E-gas, Shell, Siemens and MHI), developed at Southern Company’s Power Systems Development Facility (PSDF) in partnership with engineering company KBR, integrated with two Siemens SGT6 gas turbines and a Toshiba steam turbine – together producing 524MWe on syngas at 28.1% efficiency (high heating value basis) after taking account of the decarbonisation. Separation of 65% of the CO2 (after a water gas shift reaction) and H2S was effected using commercial UOP’s Selexol Process, with sulphur removal using Haldor Topsoe’s Wet Sulphuric Acid Process. The anticipated 3Mtpa of captured CO2 was to be transported via a 96km dedicated pipeline and destined to be used for EOR operations in the Gulf area.
The Kemper IGCC+CCS project was originally expected to be operational in mid-2014 and to cost $2.4 billion, but project management problems, environmental concerns, and modifications and repairs delayed the project starting, with project costs soaring to over $7.5 billion at the point at which the project was suspended.
So where do these mixed results leave CCS as a ‘tool in the (decarbonisation) toolbox’?
Well, these two projects are (were, in the case of Kemper County) amongst the 21 large-scale, integrated CCS projects either in operation or under construction (using the counting methodology of the Global CCS Institute, as of the end of 2016), due to lead to around 30mt of CO2 being captured and stored per year, with 17 other projects in the planning (advanced or earlier stages) expected to take this to around 40mtpa by 2020. This total needs to be viewed in the context of the approximately 4000mtpa of CO2 required to be captured and stored by 2040 under the International Energy Agency’s ‘2°C Scenario’ (2DS), with the large majority expected to be in non-OECD countries… A sobering statistic.
The Quest Project and other CCS ‘success stories’ notwithstanding, the situation with Kemper County – and indeed the fate of the ROAD Project in Europe – have ‘stoked the fires’ (if you will excuse the pun) of CCS detractors, who variously assert that either CCS in general is a waste of R&D and capital resources, or that it is not a valid approach to reducing emissions on coal.
Our view is that CCS is an crucial decarbonisation technology that has a vital role to play in mitigating climate change (i.e. achieving or bettering the IEA’s 2DS). Further RD&D is urgently needed for CCS on gas-fired power generation (with its significant challenges of low partial pressure of CO2, high partial pressure of O2 and high volumetric flows requiring very large capture facilities) and on biomass and/or biomass co-fired with fossil fuel combustion/gasification (where ‘CO2 negative’ solutions can be anticipated and are very likely to prove necessary), or for the decarbonisation of industrial processes. This said, we should not turn our backs on CCS for coal-fired power generation, as this fuel is with us for many decades to come in many parts of the world.