# A Review of Recent Progress of Carbon Capture, Utilization, and Storage (CCUS) in China
## 3 Progress of CO\({}_{2}\) Capture and Transport in China  
### Development Status of CO\({}_{2}\) Capture in China  
CO\({}_{2}\) capture is the process of capturing and separating CO\({}_{2}\) from the exhaust gases produced during the combustion of fossil fuels. The captured CO\({}_{2}\) is purified to provide a stream of high-purity high-concentrated CO\({}_{2}\) for subsequent transport, utilization and storage [57]. CO\({}_{2}\) capture technologies are classified into three categories [58], namely post-combustion capture, pre-combustion capture, and oxy-fuel combustion capture. Schematic flow diagrams of these three capture technologies are illustrated in Figure 3. In post-combustion capture, CO\({}_{2}\) is captured from flue gases after the combustion of the fuel [58]. In pre-combustion capture, fuel is pre-treated with steam and air (or oxygen) to generate syngas consisting mainly of CO and H\({}_{2}\), and then the syngas undergoes the water-gas shift reaction with steam to form CO\({}_{2}\) and more H\({}_{2}\). After CO\({}_{2}\) is separated, H\({}_{2}\) can be used as a carbon-free energy carrier to generate energy. In oxy-fuel combustion capture, the fuel is burned in pure oxygen instead of air, and the generated flue gases consist of mainly CO\({}_{2}\) and water vapor, the latter of which is easily removed through condensing, resulting in high-concentrated CO\({}_{2}\). The applicability, advantages and disadvantages of CO\({}_{2}\) capture technologies are summarized in Table 3.  
Figure 3: Schematic flow diagrams of post-combustion capture, pre-combustion capture and oxy-fuel combustion capture. Figure 2: Distribution of CCUS projects in China [50]. (**a**) CCUS project type distribution in China; (**b**) CCUS project location distribution in China. The CO\({}_{2}\) separation technology can be classified into two categories: physical method and chemical method [59], both of which can be further subdivided into absorption, adsorption, membrane separation, etc. Some comprehensive summaries of the principles, applicability, advantages and disadvantages of CO\({}_{2}\) separation technologies have been provided in detail by other literature [59; 60; 61]. The selection of capture technology mainly depends on appliance objects, and post-combustion capture is now the most developed and common technology of CO\({}_{2}\) capture in China. The Guohua Jinjie carbon capture demonstration project of China Energy Investment Group CO, Ltd. (CHN ENERGY), which was put into operation in June 2021, is currently the largest demonstration facility for CO\({}_{2}\) capture employing post-combustion capture technology, with a capture capacity of 150,000 tonnes/year [61; 62]. By utilizing post-combustion capture technology, the advanced low-energy carbon capture engineering project of Huaneng Longdong Base with a carbon capacity of 1.5 million tonnes/year, which is about to start construction, will become the largest coal-fired power plant carbon capture project in China once it is put into operation in 2023 [62]. Compared with post-combustion capture, pre-combustion capture has a more complicated system. Currently, IGCC-based pre-combustion CO\({}_{2}\) capture technology is an important technology for large-scale carbon capture demonstration in the power industry [63]. The carbon capture plant of the Huaneng IGCC power plant is China's first demonstration project with pre-combustion CO\({}_{2}\) capture technology, and it has a capture capacity of 100,000 tonnes/year after being put into operation in July 2016 [63; 64]. In addition, oxy-fuel combustion capture technology, which has the benefit of high CO\({}_{2}\) concentration for effective capture, has made significant strides. In 2016, the first 10,000-tonne pilot system for oxy-fuel combustion capture was completed in China [59; 65], and the construction of a 100,000-tonne oxy-fuel combustion industrial demonstration project has been planned [66; 67].