Insights and Commentaries
Capturing carbon from coal-to-chemicals at Yanchang
15th October 2015
The Global CCS Institute has commissioned four knowledge-sharing reports on critical aspects of carbon capture and storage (CCS) from Yanchang Petroleum Group (China). The first of these reports is now available, covering the application of carbon capture and storage (CCS) in coal–to–chemicals processes. In this Insight Tony Zhang, Senior Adviser for Carbon Capture, Asia–Pacific, provides an overview of the project and introduces the report.
Apart from its use as a fuel for electricity generation and in steel making, coal can also be used to produce a wide range of commodity chemicals such as methanol, polypropylene and polyethylene. Coal-to-chemical processes produce large volumes of carbon dioxide (CO2) and the only mature, proven technology capable of reducing emissions from coal–to–chemicals processes is CCS.
Commercial coal–to–chemicals processes are rapidly emerging, particularly in China thanks to new technologies coupled with the low price of coal. While CCS has been successfully applied to capture and store carbon emissions from coal–fired power, it is also the only proven technology option for reducing emissions from industrial coal–to–chemicals processes.
Converting coal to commodity chemicals first requires gasification of the coal, which produces syngas along with large volumes of waste CO2. While existing CCS technologies can transport and store CO2, the highest–cost component of the whole CCS chain is capture. In light of this there is a great deal of interest in optimising capture processes in coal–to–chemical plants.
China is a major emitter of greenhouse gases and the Chinese government has established policies and incentives to promote reduction of carbon emissions. Chinese governments and corporations have increased their support for CCS technology and projects in recent years.
To promote the development of CCS in China, the Global CCS Institute and China National Development and Reform Commission (NDRC) held a joint carbon capture, utilisation and storage (CCUS) workshop in Yan’An China in July 2013. Out of this collaboration the Global CCS Institute has commissioned Yanchang Petroleum Group to produce four knowledge-sharing reports on its integrated CCS project.
The four reports are:
- Capturing CO2 from the coal to chemicals process
- CO2 storage and enhanced oil recovery in a low permeability reservoir
- Measurement, monitoring and verification
- The regulation and permitting of CCUS projects in China
The reports will be published in 2015 - 2016 by the Institute. This Insight accompanies publication of the first report.
Details of the project
The coal–to–chemicals industry has developed rapidly in the last few years, particularly in coal-abundant North West China. This industry promotes alternative uses for coal but it consumes a large amount of water and has a large carbon footprint. The China National Energy Administration (NEA) recently published a draft guide on coal to liquid and gas demonstration work standards. This guide includes requirements to reduce CO2 emissions as much as possible through process optimisation and energy efficiency improvements, and to explore opportunities for CO2 enhanced oil recovery and storage.1
Yanchang Petroleum Group (Shaanxi province) owns large reserves of oil, gas, coal and salts. To optimise the utilisation of its resources Yanchang has developed technologies to convert coal, natural gas, and residual heavy oil to chemical products at its Jingbian Industry Park. The Jingbian Project has a capacity to produce 360,000 tonnes per annum (tpa) of CO2 and it uses a sub-ambient solvent technology to capture CO2 (the Rectisol Process). The capture technology itself is a relatively mature commercial technology, but as the Yanchang project is the first large-scale CCS installation in this area it was important for Yanchang to test and optimise implementation at smaller scale.
Prior to full-scale implementation at Jingbiang, Yanchang Petroleum built a smaller capture project at its Yuheng Industry Park, capturing around 50,000 tpa of CO2, which enabled Yanchang to gain significant project and operating experience for whole chain CCS operations. Lessons from the Yuheng experience have been applied in the development of the full-scale plant and have proved valuable in terms of engineering and planning activities.
The first key learning from the Yanchang project experience is the importance of planning for carbon capture readiness (CCR). At the beginning stage of the coal-to-chemical project Yanchang realised that it may need to add extra equipment for the implementation of CCS at the site. As a result, extra space was reserved for capture and compression equipment, a pipeline corridor was designed and extra power capacity was reserved for the potential CCS project.
This cost more money to the project at the time, but had these measures not been put in place it would have cost much more to re-design and modify the capture plant to implement the full chain of CCS at a later date. It is important for other project developers to undertake similar planning if CCS is a possibility.
The second key learning from the study is that large scale CCS projects require a qualified and experienced project manager. The complex nature of integrated CCS projects mean that many different technology vendors will be engaged to achieve the whole chain operation. Yanchang itself has not had significant experience with such a large project and so it hired a professional project management company to manage the project on its behalf. For the implementation of the project, Yanchang abandoned its old model of Engineering + Procurement + Construction (EPC) which entailed three separate vendors and three separate contracts. Instead, Yanchang hired an overall EPC company for this project which only required one contract while greatly streamlining and simplifying the process. For Yanchang, this has been an extremely valuable culture transition that has enabled Yanchang to train and to develop its own expertise.
Other key learnings from the project include:
- ensuring proximity of emission sites to storage sites
- adopting proven technology where possible
- importance of staff training
- selection of transport method based on actual local conditions
- flexibility of compression unit for early CCS movers
More importantly, like elsewhere, a consistent energy and climate change policy is needed for corporations to conduct CCS projects. The Yanchang Project has been supported by China National Development and Reform Commission (NDRC) and local governments in the form of direct funding, policy and other incentives. The policy support and the commercial drivers are key success factors for this project.
In summary, the Yanchang Project has broken important new ground in developing large scale CCS projects in China. Experiences from the capture project will clearly benefit Yanchang and other corporations throughout China. Furthermore, the Yanchang experience has provided a valuable direction for development of coal–to–chemical processes in China.
1 China National Energy Administration 2015. Guide on regulating coal to fuel demonstration work. 2nd draft for consultation. Beijing: CNEA.