User:Santosojonathan/sandbox

Hi! Welcome to my sandbox page! I am currently working on a carbon capture and utilization page (see draft). Please look around and feel free to leave me feedbacks!

Carbon Capture and Utilization (CCU)
Carbon Capture and Utilization (CCU) differs from CCS as CCU does not result in geological storage of carbon dioxide. Carbon capture and utilization may offer a response to the global challenge of significantly reducing greenhouse gas emissions from major stationary (industrial) emitters. CCU aims to use the carbon dioxide produced to make other substances (e.g. plastics, concrete, biofuel) such that the whole process is carbon neutral.

There are several technologies available in CCU such as: converting CO2 to products such as methanol, biofuel, and other forms of hydrocarbons. Some other forms of CCU includes the converting CO2 to commercial products such as plastics, concrete and reactants for various chemical synthesis.

Though CCU does not result in a net carbon positive to the atmosphere, there are several important considerations to be taken into account. The energy requirement for the additional processing of new products should not exceed the amount of energy released from burning fuel as the process will require more fuel. It should be noted that making products from CO2 is energy intensive as it CO2 is thermodynamically stable. In addition, concerns on the scale of CCU is a major argument against investing in CCU. The availability of other raw materials to create a product should also be considered before investing in CCU.

One of the drivers for the possible implementation of CCU is a price on carbon. A price on carbon will incentivize the reduction of CO2 being released into the atmosphere. Thus, CCU can be one of the main alternatives for company to use the CO2 they produced to make another product that they can sell.

Sources of Carbon
CO2 are typically captured from fixed point sources such as power plants and factories. CO2 captured from these exhaust stream itself varies in concentration. A typical coal power plant will have 10-12% CO2 concentration in its flue gas exhaust stream. A biofuel refinery produces a high purity (99%) of CO2 with small amount of impurities such as water and ethanol.

Chemical Synthesis
Also known as chemical feedstock, CO2 captured previously will be used to be converted to a diverse range of products. Some of these products include: polycarbonates (via Zinc based catalyst) or other organic products such as acetic acid, urea , and PVC. Based on a report in March 2011, this technology requires 1-5 years to commercialization. Chemical synthesis is not a permanent storage/utilization of CO2, as aliphatic (straight chain) compounds may degrade and release CO2 back to the atmosphere as early as 6 months. However, this technology is easily retrofitted into existing technology.

Industrial example of chemical synthesis: Novomer
Novomer is a chemical industry working in the synthesis of everyday used products. They are working in two different types of plastics: polyethylene carbonate (PEC) and polypropylene carbonate (PPC) and claimed that their products contains up to 50% CO2 by mass. Based on a March 2011 report by Global CCS Institute, they could see a market share of 22.5 MtCO2/yr. They have received funding from multiple sources such as the Department of Energy (DOE) ($2.6 million) and NSF ($400,000) to achieve commercialization as well as converting their production process from a batch process to a continuous process. Their pilot plant opened back in December 2009 with a 1500L batch reactor and utilized waste stream from ethanol fermentation and flue gas as their source of CO2.

The advantage of chemical synthesis by Novomer is that there is a diverse choice for characteristics of plastics being made. This helps avoid the scarcity of resources if this technology are to be scaled up. Another advantage is that the CO2 sources won't compete with food production.

Some of the disadvantage of this technology is that as this technology is relatively new, there needs to be more research being done on various parts of the synthesis such as the zinc-based catalyst. The choices for its source of CO2 itself may give rise to the need of another separation process to increase the quality of CO2. A big problem present in Novomer's case is the competition with existing packaging industry. The current demand for packaging prefers cheap low-end application of polymer. This may prove to be difficult for the CO2 utilization for polymers to enter the market of packaging industry.

Enhanced Oil Recovery (EOR)
In EOR, CO2 is going to be injected into depleted oil fields in hopes to increase the amount of oil to be extracted by the wells. This method is proven to increase oil output by 5-40%. The scale of CO2 utilization through this technologies ranges from 30-300 MtCO2/yr. It is a permanent and mature technology in CCU. A power plant in LaBarge, WY, has utilized 23-25 MtCO2/yr since 1986. The biggest market driver for EOR is the heavy reliance on oil. In United States, some of the additional market drivers include: tax revenue for foreign oil as well as the presence of carbon tax credits.

Environmental Impact of CCU Technologies
16 life cycle environmental impact analysis have been done to assess the impacts of four main CCU technologies against conventional CCS: Chemical synthesis, carbon mineralization, biodiesel production, as well as Enhanced Oil Recovery (EOR). These technologies were assessed based on 10 life cycle assessments (LCA) impacts such as: acidification potential, eutrophication potential, global warming potential, and ozone depletion potential. The conclusion from the 16 different models was that chemical synthesis has the highest global warming potential (216 times that of CCS) while enhanced oil recovery has the least global warming potential (1.8 times that of CCS). In general, CCS poses the best impact relative to the four CCU technologies.

== Note: The part above is ready to be edited. I am planning to make a short summary on some of the examples from the original page below. Please don't edit this part below. This is for another page I'm working on. == Technologies under development, such as Bio CCS Algal Synthesis, utilizes pre-smokestack CO2 (such as from a coal-fired power station) as a useful feedstock input to the production of oil-rich algae in solar membranes to produce oil for plastics and transport fuel (including aviation fuel), and nutritious stock-feed for farm animal production[citation needed]. The CO2 and other captured greenhouse gases are injected into the membranes containing waste water and select strains of algae causing, together with sunlight or UV light, an oil rich biomass that doubles in mass every 24 hours[citation needed]. The Bio CCS Algal Synthesis process is based on earth science photosynthesis: the technology is entirely retrofittable and collocated with the emitter, and the capital outlays may offer a return upon investment due to the high value commodities produced (oil for plastics, fuel and feed). Bio CCS Algal Synthesis test facilities were being trialed at Australia's three largest coal-fired power stations (Tarong, Queensland; Eraring, NSW; Loy Yang, Victoria) using piped pre-emission smokestack CO2 (and other greenhouse gases) as feedstock to grow oil-rich algal biomass in enclosed membranes for the production of plastics, transport fuel and nutritious animal feed.

Another potentially useful way of dealing with industrial sources of CO2 is to convert it into hydrocarbons where it can be stored or reused as fuel or to make plastics. There are a number of projects investigating this possibility.

Carbon dioxide scrubbing variants exist based on potassium carbonate which can be used to create liquid fuels, though this process requires a great deal of energy input. Although the creation of fuel from atmospheric CO2 does not result in carbon dioxide removal as carbon dioxide is re-released when the fuel is burned. Therefore, synfuels do not represent a climate engineering technique. Nevertheless, they are potentially useful as net-zero-carbon fuel.

Other uses are the production of stable carbonates from silicates (e.g. olivine produces magnesium carbonate). These processes are still under research and development.

Single step methods: methanol[edit]
A proven process to produce a hydrocarbon is to make methanol. Methanol is easily synthesized from CO2 and H2. Based on this fact the idea of a methanol economy was born.

Single step methods: hydrocarbons[edit]
At the department of Industrial Chemistry and Engineering of Materials at the University of Messina, Italy, there is a project to develop a system which works like a fuel-cell in reverse, whereby a catalyst is used that enables sunlight to split water into hydrogen ions and oxygen gas. The ions cross a membrane where they react with the CO2 to create hydrocarbons.

Two step methods[edit]
If CO2 is heated to 2400 °C, it splits into carbon monoxide (CO) and oxygen. The Fischer-Tropsch process can then be used to convert the CO into hydrocarbons. The required temperature can be achieved by using a chamber containing a mirror to focus sunlight on the gas. Rival teams are developing such chambers, at Solarec and at Sandia National Laboratories, both based in New Mexico. According to Sandia these chambers could provide enough fuel to power 100% of domestic vehicles using 5800 km2; unlike biofuels this would not take fertile land away from crops but would be land that is not being used for anything else. James May, the British TV presenter, visited a demonstration plant in a programme in his Big Ideas series.