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Showing posts with label carbon sequestration. Show all posts
Showing posts with label carbon sequestration. Show all posts

Friday, January 3, 2014

Coal may be the Problem and the Solution too!

Can renewable energy really stop GHG emissions and global warming? Renewable energy is slowly but steadily becoming a choice of energy of the people due to its potential to reduce GHG emissions and global warming. The changing weather pattern around the world in recent times are testimony for such a warming globe. Can renewable energy really reduce the GHG emissions and reduce the global warming predicted by scientists? Thousands of large coal- fired power plants are already under implementation or planning stages. According to World’s resources institute, their key findings are : 1. According to IEA estimates, global coal consumption reached 7,238 million tonnes in 2010. China accounted for 46 percent of consumption, followed by the United States (13 percent), and India (9 percent). 2. According to WRI’s estimates, 1,199 new coal-fired plants, with a total installed capacity of 1,401,278 megawatts (MW), are being proposed globally. These projects are spread across 59 countries. China and India together account for 76 percent of the proposed new coal power capacities. 3. New coal-fired plants have been proposed in 10 developing countries: Cambodia, Dominican Republic, Guatemala, Laos, Morocco, Namibia, Oman, Senegal, Sri Lanka, and Uzbekistan. Currently, there is limited or no capacity for domestic coal production in any of these countries. 4. Our analysis found that 483 power companies have proposed new coal-fired plants. With 66 proposed projects, Huaneng (Chinese) has proposed the most, followed by Guodian (Chinese), and NTPC (Indian). 5. The “Big Five” Chinese power companies (Datang, Huaneng, Guodian, Huadian, and China Power Investment) are the world’s biggest coal-fired power producers, and are among the top developers of proposed new coal-fired plants. 6. State-owned power companies play a dominant role in proposing new coal-fired plant projects in China, Turkey, Indonesia, Vietnam, South Africa, Czech Republic and many other countries. 7. Chinese, German, and Indian power companies are notably increasingly active in transnational coal-fired project development. 8. According to IEA estimates, the global coal trade rose by 13.4 percent in 2010, reaching 1,083 million tonnes. 9. The demands of the global coal trade have shifted from the Atlantic market (driven by Germany, the United Kingdom, France and the United States) to the Pacific market (driven by Japan, China, South Korea, India and Taiwan). In response to this trend, many new infrastructure development projects have been proposed. 10. Motivated by the growing Pacific market, Australia is proposing to increase new mine and new port capacity up to 900 million tonnes per annum (Mtpa) — three times its current coal export capacity. The above statistics is a clear indication that GHG emissions by these new coal-fired power plants will increase substantially. A rough estimation indicates that these new plants will emit Carbon dioxide at the rate of 1.37 mil tons of CO2/hr or 9.90 billion tons of CO2 /yr in addition to the existing 36.31 Gigatons/yr (36.31 billion tons/yr) in 2009. (According to If this is true, the total CO2 emissions will double in less than 4 years. If the capacity of new PV solar plants are also increased substantially then the CO2 emissions from PV solar plants will also contribute additionally to the above. There is no way the CO2 reduction to the 2002 level can be achieved and the world will be clearly heading for disastrous consequences due to climate change. The best option to reduce GHG emissions while meeting the increasing power demand around the world will be to recycle the Carbon emissions in the form of a Hydrocarbon with the help of Hydrogen. The cheapest source of Hydrogen is coal. The world has no better option than gasifying the coal instead of combusting the coal. Capturing Carbon and recycling it as a fuel : Solar power, wind power and other renewable energies generated 6.5% of the world’s power in 2012. This is part of a rising trend , but there is a very long way to go before renewable sources generate as much energy as coal and other fossil fuels. Solar panel of 1m2 size requires 2.4kg of high grade silica and Coke and it consumes 1050 Kwh of electricity, mostly generated by fossil fuel based power plants. But 1m2 solar panel can generate only 150kwh/yr and it will require at least 7 years to generate the power used to produce 1m2 solar panel in the first place. More solar panels mean more electricity consumption and more GREEN HOUSE GAS EMISSIONS.A large quantity of CO2 will have to be emitted into the atmosphere for the production of several GW (Giga- watts) of solar power.With thousands of newly planned and implemented coal fired power plants in the near future the greenhouse gas emission is likely to go up. It could take at least thirty years before renewable energy is as strong in the marketplace as non-renewable sources. In consequence, there is a need to use fossil fuels more effectively and less detrimentally until the renewables can play a major role in global energy production. One approach tried for more than a decade has been carbon capture, which stops polluting materials getting into the atmosphere; however subsequent storage of the collected materials can make this process expensive. Now an Australian based company has gone one step further and designed a process that not only collects CO2 emissions, but also turns it into a fuel by using the same coal! Clean Energy and Water Technologies has developed an innovative solution to avoid carbon emissions from power plants. The novel approach uses coal to capture carbon dioxide emissions (CO2 ) from coal-fired power plants and convert them into synthetic natural gas (SNG). Synthetic natural gas would then replace coal as a fuel for further power generation and the cycle would continue. No coal is required for further power generation. Through this method, the captured Carbon could be recycled again and again in the form of a Hydrocarbon fuel (SNG) with no harmful gas emissions. Carbon is an asset and not a liability. If Carbon is simply burnt away just to generate heat and power then it is a bad science, because the same Carbon can be used to generate several products by simply recycling it instead of venting out into the atmosphere. Carbon is the backbone of all valuable products we use every day from plastics to life saving drugs! As well as seeking a patent for this breakthrough innovation, Clean Energy and Water Technologies is seeking investment for a demonstration plant. Once demonstrated, it would then be possible to retrofit current coal-fired power stations with the new technology, increasing their economic sustainability and reducing their impact on the environment. 1. The Economic Pressures : Power is an integral part of human civilization. With the steady increase in human population and industrialization the demands for energy and clean water has reached unprecedented levels. The gap between the demand and supply is steadily pushing the cost of power and water higher, whilst the supply of coal, oil and gas is dwindling. The prospect of climate change has compounded problems. Many countries around the world have started to use renewable energy such as solar, wind, hydro and geo-thermal power; but emerging economies such as India and China are unable to meet their demands without using fossil fuels. At present, it is far cheaper to use the existing infrastructures associated with non-renewable energy, such as coal-fired power stations. Renewable energy sources are intermittent in nature and require large storage and large initial investment, with sophisticated technologies pushing the cost of investment higher. Governments could use environmental tariffs on power use to help make renewable energy more competitive, but politicians know that the public tend to not like such an approach. 2. Demonstration Plant: The estimated investment required for a demonstration plant is likely to be $10 million; however the potential for a good return on investment is high, as shown by the following estimation for a 100MW plant. • A 100MW coal-fired power plant will emit 98 Mt/hr CO2 • Coal consumption will be about 54Mt/hr • To convert 98Mt/hr CO2 into SNG, the plant needs to generate 390,000m3/hr syngas by coal gasification. • The gasification plant will require 336 Mt/hr coal and 371 m3/hr water. • The net water requirement will be : 95.70m3/hr • The SNG generated by the above plant will be : 95,700m3/hr and steam as by-product : 115Mt/hr. • Potentially SNG can generate a gross power of 500 MWS by a Gas turbine with combined cycle operation. • The plant can generate 500MW (five times more than the coal-fired plant) from CO2 emissions. • Existing 100MW coal fired power plant can use SNG in place of coal and sell the surplus SNG to consumers. • Surplus SNG will be about 75,000 m3/hr.( 2400 mm Btu/hr) with sale value of $36,000/hr. @ $15/mmBtu. • Annual sales revenue from sale of surplus SNG will be : $ 300 mil/yr. • The entire cost of coal gasification and SNG plant can be recovered back in less than 5 years. 3. Carbon Capture and Storage : Carbon capture and storage is the process of capturing waste carbon dioxide (CO2 ) from large point sources, such as fossil fuel power plants, transporting it to a storage site, and depositing it where it will not enter the atmosphere, normally an underground geological formation. The aim is to prevent the release of large quantities of CO2 into the atmosphere. It is a potential means of mitigating the contribution of fossil fuel emissions to global warming and ocean acidification. The long term storage of CO2 is a relatively new concept. The first commercial example was Wey burn in 2000. Carbon capture and storage applied to a modern conventional power plant could reduce CO2 emissions to the atmosphere by approximately 80–90%, but may increase the fuel needs of a coal-fired plant by 25–40%. These and other system costs are estimated to increase the cost of the energy produced by 21–91% for purpose built plants. Applying the technology to existing plants could be even more expensive. 4. Global Warming : Global warming is the rise in the average temperature of Earth's atmosphere and oceans since the late 19th century and its projected continuation. Since the early 20th century, Earth's mean surface temperature has increased by about 0.8 °C (1.4 °F), with about two-thirds of the increase occurring since 1980. Scientists are more than 90% certain that it is primarily caused by increasing concentrations of greenhouse gases produced by human activities such as the burning of fossil fuels by coal-fired power plants. 5. Greenhouse Gases Without the earth's atmosphere the temperature across almost the entire surface of the earth would be below freezing. The major greenhouse gases are water vapour, which causes about 36–70% of the greenhouse effect; carbon dioxide (CO2 ), which causes 9–26%; methane (CH4), which causes 4–9%; and ozone (O3), which causes 3–7%. According to work published in 2007, the concentrations of CO2 and methane have increased by 36% and 148% respectively since 1750. These levels are much higher than at any time during the last 800,000 years, the period for which reliable data has been extracted from ice cores. 6. The Future of Global Warming?: Climate model projections were summarized in the 2007 Fourth Assessment Report by the Intergovernmental Panel on Climate Change (IPCC). They indicated that during the 21st century the global surface temperature is likely to rise a further 1.1 to 2.9 °C (2 to 5.2 °F) for their lowest emissions scenario and 2.4 to 6.4 °C (4.3 to 11.5 °F) for their highest. 7. The Impact of Global Warming? : Future climate change and associated impacts will vary from region to region around the globe. The effects of an increase in global temperature include a rise in sea levels and a change in the amount and pattern of precipitation, as well a probable expansion of subtropical deserts. Warming is expected to be strongest in the Arctic and would be associated with the continuing retreat of glaciers, permafrost and sea ice. Other likely effects of the warming include a more frequent occurrence of extreme weather events including heat waves, droughts and heavy rainfall, ocean acidification and species extinctions due to shifting temperature regimes. There is a divided opinion among scientists on climate science. Major power consuming countries like the US, Europe, Japan and Australia are reluctant to sign the Kyoto Protocol and agree to a legally binding agreement. This has resulted in non-cooperation among the nations and the world is divided on this issue. Such disagreement has hampered development of non-renewable energy. Ahilan Raman is the inventor of the innovative process mentioned in the article. If you have any further questions or like to become a part of this innovative technology, please feel free to contact him directly by writing to this blog.

Thursday, April 26, 2012

Recycling Carbon emissions to Gasoline production

Nature has a wonderful way of capturing Carbon and recycling it through a process called ‘carbon cycle’ for millions of years. The greenhouse gases in the atmosphere were restricted within certain limits when it was left to Nature. But when human being started burning fossil fuels to generate power or to run cars, the GHG emission surpassed the limit beyond a point where global warming became an issue. The GHG level has increased to 392 ppm level for the first in our long history. Many Governments and companies are exploring various ways and means to reduce greenhouse emissions to avoid global warming. Some Governments are imposing taxes on carbon emission in order to reduce or discourage such emissions. Others are offering incentives to promote alternative energy sources such as wind and solar. Some companies are trying to capture Carbon emission for sequestration. While we try to capture Carbon and store them underground, there are many potential commercial opportunities to recycle them. This means the Carbon emission is captured and converted into a commercial fuel such as Gasoline or Diesel or Methane so that future sources of fossil fuels are not burnt anymore. But this is possible only by using ‘Renewable Hydrogen’. Hydrogen is the key to reduce carbon emission by binding carbon molecules with Hydrogen molecule, similar to what Nature does. When NASA plans to send a man to Mars they have to overcome certain basic issues. Mars has an atmosphere with 95% Carbon dioxide, 3% Nitrogen, 1.6% Argon and traces of oxygen, water and methane.Nasa is planning to use Carbon dioxide to generate Methane gas to be used as a fuel and also generate water by using the following reaction. CO2 + 4H2-----CH4 + 2 H2O, 2H2O-------2H2 + O2 The water is electrolyzed to split water into Hydrogen and Oxygen using solar power. The resulting Hydrogen is reacted with Carbon dioxide from Mars to generate Methane gas and water using a solid catalyst. This methanation reaction is exothermic and self sustaining. How this can be achieved practically in Mars in those conditions are not discussed here. But this is a classical example on how the Carbon emission can be tackled to our advantages, without increasing the emissions into the atmosphere. There are several methods available to convert Carbon emission in to valuable products including gasoline. The reaction of the methane with water vapor will result in Methanol. 2H2 + CO-------- CH3OH On Dehydration, 2CH3OH ----- CH3COCH3 + H2O.Further dehydration with ZSM-5 Catalyst gives Gasoline 80% C5+ Hydrocarbon. Gas to liquid by Fischer-tropic reaction is a known process. Carbon dioxide is also a potential refrigerant to substitute CFC refrigerants that causes Ozone depletion. Carbon recycling is a temporary solution to mitigate Greenhouse gas emission till Hydrogen becomes an affordable fuel of the future. It depends upon individual Governments and their policies to make Hydrogen affordable. Technologies are available and only a political will and leadership can make Hydrogen a reality.

Saturday, April 21, 2012

Carbon capture or Carbon recycle?

We live in a carbon constrained world where carbon emission is considered as the biggest challenge of the twenty first century. We unearthed fossil fuel which Nature buried for millions of years and burnt them for our advantage to generate power and to run our cars. Scientists pointed out that the unabated emission of greenhouse will cause the globe to warm with dire consequences.This came as an ‘inconvenient truth’ to industries and Governments around the world. However, economic consequences of stopping fossil fuels outweiged the impact of global warming. Governments were in a precarious situation and were unable to take a concrete policy decision. Popular Governments were not willing to risk their power by taking ethical decisions and opted for popular decision to maintain their growth. Then the financial crisis became an issue, which has nothing to do with greenhouse emission or global warming. Yet, the economic and industrial growth stumbled in many developed countries and unemployment skyrocketed. Governments are caught in a situation where they need to take a balanced view between an ethical decision and economic decisison.The overwhelming evidence of global warming and their consequences are slowly felt by countries around the world by natural disasters of various sizes and intensities. Some scientists suggested that there was nothing wrong using fossil fuels; we could continue with greenhouse emission without risking the economic growth by capturing the carbon and burying them underground. Carbon sequestration and clean coal technologies became popular and more funds were allocated to them than renewable energy development.Countires like India and China were not in a hurry to discontinue fossil fuels but continued to make massive investments on coal fired power plants. They neither try to capture carbon nor bury them, but continue to emit carbon claiming that it is their turn of economic growth and right to emit carbon emission. The chief of UN panel on climate change headed by an Indian has no say in the matter.Politicians push scientists into the background whenever the truth is inconvenient to them. How feasible in the carbon sequestration technology and what is the cost? Even if we can come up with a successful technology of capturing carbon and burying them underground, there will be a cost involved. This cost will invariably be passed on to the consumer which will eventually increase the cost of energy. Constraining carbon emission without incurring a cost can only be a dream. Capturing carbon emission is nothing new; Carbon dioxide is absorbed by solvents like MEA (Monoethanolamine) in many chemical industries. The absorbed carbon dioxide can be stripped free of solvent and the solvent can be recycled. This carbon dioxide can be treated with Ammonia to get Urea, a Fertilizer. But the source of Hydrogen can come only from renewable energy sources. That is why ‘Renewable Hydrogen ‘is the key to solve global warming problem. We can produce Urea from “captured Carbon” and ‘Renewable Hydrogen’ so that we can reduce a substantial quantity of greenhouse emission. Carbon recycling is a sustainable solution than Carbon capturing and burying. Countries like India who depend upon import of Urea for their agriculture production should immediately make Carbon recycling into Urea production mandatory. It is a win situation for everybody in the world.

Thursday, March 8, 2012

Hydrogen from Coal

Coal is an important fuel that helped industrial revolution. It is still a predominant fuel for power generation in many parts of the world. It is also an important raw material for number of chemicals and they directly compete with Hydrocarbons such as Naptha.It is abundantly available and it is cheap. We are still able to generate electricity at 5 cents per kwhr using coal. But, now we are entering into a new phase of energy generation and distribution, due to changing environmental and climatic issues of the twenty first century. We require completely a new fuel to address these issues; a fuel that has a higher heat content, which can generate more power per unit value of fuel, and yet, generates no pollution. It is a challenging job and the world is gearing up to meet these challenges. They affect the whole world because any issues concerning energy impacts each and every one of us. Many industrialized countries around the world are reluctant to sign an agreement that compels them to reduce their greenhouse emission to an acceptable level set by UN panel of scientists. Governments such as US, China and India are reluctant to sign such an agreement because their economy and growth depends upon cheap energy, made from coal. Such an agreement will be detrimental to their progress, and the leaders of these nations are not prepared to sign such an agreement. They also understand that world cannot afford to continue to use coal as they have used in the past. It is simply unsustainable. It is a precarious situation and they need to carefully plan their path forward. On one hand, they need to maintain their industrial and economical growth, and on the other hand they need to reduce their emissions and save the world, from catastrophic consequences of global warming. A simple analysis of the fuel will indicate that Hydrogen is a potential energy source for the future. It has energy content at least five times more than a coal for a unit value. Coal has an average heat content of 5000 kcal /kg while Hydrogen has an average heat content of 39,000 kcal/kg. Coal has a number of impurities such as ash, sulfur, phosphorous, other than carbon. Burning coal will emit greenhouse gases with toxic fumes that have to be removed. Therefore, these industrialized countries are now looking ways to generate Hydrogen from coal; that too at a cost which will be comparable to other current fuels such as natural gas. It is not an easy task because natural gas is formed by Mother Nature over several hundred thousand years. It is readily available and there is no manufacturing cost except processing cost. We are used to free energy from Mother Nature. This is the crux of the issue. Hydrogen is the most abundantly available element on earth; yet it is not available in a free form. It is available as a compound, for example, joined with oxygen forming water H2O molecule; or joined with Carbon forming Methane CH4 molecule.This Hydrogen should be separated in a free form, and this separation requires energy. How can coal, which is just a Carbon, generate Hydrogen? It requires an addition of water in the form of steam. When coal is gasified with air and steam, a mixture of Hydrogen and Carbon dioxide is generated, known as Syngas (synthesis gas). 2C + H2O+O2 ------- 2H2 +2 CO2 The syngas is separated into Hydrogen and carbon dioxide using various methods using their difference in densities. The Hydrogen can be stored under pressure for further use. Research work is currently under way to capture carbon dioxide for sequestering. Carbon sequestration is a method of capturing carbon dioxide and storing it in a place where it cannot enter the atmosphere. But the technical feasibility and economic viability of such a system is yet to be established. Carbon sequestration is a new concept and the cost of sequestration can potentially increase the cost of energy derived from Hydrogen despite the fact, Hydrogen has energy content five times more the carbon. However, there is no quick fix for our energy problems, and we have to reconcile to the fact that the energy cost will increase in the future but eventually reduce the greenhouse emissions. These developed countries should at least disclose to the rest of the world, how they plan to reduce their emissions and their action plans; such disclosure should be subject to inspection by UN panel. In the absence of any concrete mechanism, it will be impossible to stop the global warming in the stipulated time frame considering the fact that a number of coal/oil/gas fired power plants are already under implementation.