The Emerging Electrical Markets for Copper
Figure 87: Main Routes to Carbon Capture28
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- Post-Combustion Capture
- Pre-Combustion Capture
- Ocean Storage
- Figure 88: Status of CCS Component Technology Development 29
Figure 87: Main Routes to Carbon Capture28 
CO2 Capture The capture and compression technologies for CO2 form the foundation that underpins the global deployment of commercial scale CCS projects. It is also highly costly. Currently, there are three main routes to carbon capture: a) post combustion, b) pre-combustion and c) oxyfuel. Post-Combustion Capture: This involves separating the CO2 from other exhaust gases after combustion of the fossil fuel. Post-combustion capture systems are similar to those that already remove pollutants such as particulates, sulphur oxides and nitrogen oxides from many power plants. Pre-Combustion Capture: This involves separating CO2 before the fuel is burned. Solid or liquid fuels such as coal, biomass or petroleum products are first gasified in a chemical reaction at very high temperatures with a controlled amount of oxygen. Gasification produces two gases, hydrogen and carbon monoxide (CO). The CO is converted to CO2 and removed, leaving pure hydrogen to be burned to produce electricity or used for another purpose. The hydrogen can be used to generate power in an advanced gas turbine and steam cycle or in fuels cells, or a combination of both. Oxyfuel Combustion: This involves the combustion of coal in pure oxygen, rather than air, to fuel a conventional steam generator. By avoiding the introduction of nitrogen into the combustion chamber, the amount of CO2 in the power station exhaust stream is greatly concentrated, making it easier to capture and compress. Oxyfuel combustion with CO2 storage is currently at the demonstration phase. CO2 Transport At the site of carbon capture, most technologies require the CO2 to be compressed into a supercritical fluid ready for transport and geological (or other) storage. The technology for CO2 transportation and its environmental safety are well-established. CO2 is largely inert and easily handled and is already transported in high pressure pipelines. In the USA, CO2 is already transported by pipeline for use in Enhanced Oil Recovery (EOR). The means of transport depends on the quantity of CO2 to be transported, the terrain and the distance between the capture plant and storage site. In general, pipelines are used for large volumes over shorter distances. In some situations or locations, transport of CO2 by ship may be more economic, particularly when the CO2 has to be moved over large distances or overseas. Land transport is expensive, and likely to be employed only in small and demonstration projects. Sea transport of CO2 has not yet been developed. As the vessels required would be similar to those currently used to transport LNG or LPG, it is thought that this could be developed as a transport method for CO2 quite easily. Whatever the mode of transport chosen, account needs to be taken of the risk in moving CO2. Although CO2 is an inert, non-flammable gas, it still has the potential to be dangerous. As CO2 is 1.5 times heavier than air it will displace oxygen in confined spaces (such as valleys). At high concentrations, CO2 can lead to a range of adverse health effects, including asphyxiation. CO2 Storage CO2 storage, also called CO2 sequestration, refers to processes that keep CO2 from being emitted to the atmosphere by storing it in a location where it will remain trapped for thousands of years or longer. Most carbon sequestration processes store CO2 away from the atmosphere, at great depth within the earth’s crust, often below the ocean floor. Other alternatives are being explored, however, One carbon storage process, called terrestrial storage, stores CO2 in plant cell material and in soil organic matters, locked in a solid form. There are four main methods either being considered or now being used for carbon sequestration. Geological Storage: This refers to the sequestration of carbon in deep porous rock formations that are isolated from the atmosphere by thick layers of impermeable rock. The CO2 is stored in the pore spaces between mineral grains that make up rocks such as sandstone or limestone, or within voids or cavities within rocks such as basalt or salt. Ocean Storage: This refers to storage within deep ocean basins. Beneficial Reuse: This refers to systems where CO2 is used for practical purposes, such as for Enhanced Oil Recovery, but there is also a component of carbon storage Terrestrial Storage: This refers to the locking of CO2 in biological material on land in forests or grasslands, and in algae. Figure 88: Status of CCS Component Technology Development29 
Technology Readiness The discussion of CCS technologies above indicates that technologies are in place, or well on the way to being so. This is, however, a market that is only at an early stage of development. It may be expected that as it develops new, cheaper and more efficient technologies will come to the fore. As an indication of the state of technology readiness of the main capture, transport and storage options proposed, we show the relative status of development in Figure 88. Directory: wordpress -> wp-content -> uploads -> 2017 uploads -> Professor rona s beattie and dr david bamaung glasgow caledonian university email for corresponding author uploads -> Best Offensive Players: qb #19 keenan reynolds, N, ’16. Lg #57 E. K. Binns, N, ’16 uploads -> Smart Supervision Research Partner Orientation Course fy13 and fy14 Grantees September 29- october 1, 2015/San Antonio, tx uploads -> Autonomous Control for a Reliable Internet of Services (across) 2017 -> 6 Thai Market Analysis 2017 -> Birchwood intermediate school 2017 -> Operation corporate 2017 -> This document is written for the amateur radio operator that will be using the PiGate as an emergency communications device in a disaster situation Download 10.26 Mb. Share with your friends:
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