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“Over two-thirds of today’s proven reserves of fossil fuels need to still be in the ground in 2050 in order to prevent catastrophic levels of climate change” – a warning by scientists.

There is a great deal of debate on climate change due to man-made Carbon emissions and how to control it without any further escalation. The first obvious option will be to completely stop the usage of fossil fuel with immediate effect. But it is practically not feasible unless there is an alternative Non-Carbon fuel readily available to substitute fossil fuels. The second option will be to capture carbon emission and bury them under ground by CCS (Carbon capture and sequestration) method. But this concept is still not proven commercially and there are still many uncertainties with this technology, the cost involved and environmental implications etc.The third option will be not to use fresh fossil fuel  for combustion or capture and bury the Carbon emissions but convert the  Carbon emissions into a synthetic hydrocarbon fuel such as synthetic natural gas (SNG) and recycle them. By this way the level of existing Carbon emission can be maintained at current levels without any further escalation. At least the Carbon emission levels can be reduced substantially and maintained at lower levels to mitigate climate changes. It is technically feasible to implement the third option but it has to be implemented with great urgency.

One way of converting Carbon emission is to capture and purify them using conventional methods and then react with Hydrogen to produce synthetic natural gas (SNG)

CO2 + 4 H2 ———> CH4 + 2 H2O

The same process will be used by NASA to eliminate carbon built-up in the flights by crew members during their long voyage into the space and also to survive in places like Mars where the atmosphere is predominantly carbon dioxide. But we need Hydrogen  which is renewable so that the above process can be sustained in the future .Currently the cost of Hydrogen production using renewal energy sources are expensive due to high initial investment and the large energy consumption.

We have now developed a new process to generate syngas using simple coal, which is predominantly Hydrogen to be used as a Carbon sink to convert Carbon emissions into synthetic natural gas (SNG). The same Hydrogen rich syngas can be directly used to generate power using gas turbine in a simple or combined cycle mode. The Carbon emission from the gas turbine can be converted into SNG (synthetic natural gas) using surplus Hydrogen-rich  syngas. The SNG thus produced can be distributed for CHP (combined heat and power) applications so that the Carbon emission can be controlled or distributed. By implementing the above process one should be able to maintain Carbon at specific level in the atmosphere. Existing coal-fired power plants can retrofit this technology so that they will be able to cut their Carbon emissions substantially; they can also produce SNG as a by-product using their Carbon emissions and achieve zero Carbon emission at their site while generating revenue by sale of SNG.

Coal is the cheapest and widely used fossil fuel for power generation all over the world. Therefore it will be a win situation for everyone to use coal and also to cut Carbon emissions that can address the problems of climate change. Meanwhile research is going on to generate renewable Hydrogen cheaply directly from water using various technologies. But we believe we are still far away from achieving this goal and we require immediate solution to address our climate change problems.

Recently BASF made a press release : http://www.basf.com/group/press release/P-13-351‎ claiming a break-through technology to generate Hydrogen from natural gas without any CO2 emissions.

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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. Scientist pointed out that the unabated emission of greenhouse will cause the globe to warm with dire consequences. However this came as an ‘inconvenient truth’ to industries and Governments around the world. The economic consequences of stopping fossil fuels weighted more than the global warming. Governments were in a precarious situation and 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 keep up 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 scientist suggested that there is nothing wrong using fossil fuels; we can continue with greenhouse emission without risking the economic growth by  capturing  the carbon emission 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 are not in a hurry to discontinue fossil fuels but continue to make massive investments on coal-fired power plants. They neither tried 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 sayin the matter.Politicians push scientists into the background when 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 cut a real 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.

Dirty coal is still a popular choice for power generation around the world, irrespective of the status of the country, whether industrially advanced or backward. The abundant availability and cheap cost, makes coal more attractive from investor’s point of view; they care less for the environment, while Governments turn a blind eye to all the emissions and pollutions. It is a question of survival for millions of people who work in coal mines and industries. It is one of the toughest challenges many Government are facing. Take for example India; about 65% of power generation still comes from coal. The import of coal increases year after year and there is no immediate solution in sight. Indian coal is a low-grade coal with very high ash content. Each coal-fired power plant generates a huge amount of fly ash and they stockpile them; supposed to be used in the production of Portland cement. It is a big business.

China and Indonesia too uses coal as a major fuel for power generation. But they have come out with an innovative and pragmatic method of using coal. They use coal-water-slurry (CWS), a finely pulverized high  grade coal (calorific value 5100-6100Kcal/kg) in water. They use some chemical additives that make the slurry a homogeneous fluid, similar to a Hydrocarbon such as Heavy fuel oil (HFO).The advantage with CWS is it can be easily pumped and injected into a furnace or boiler using ceramic nozzles, obviously to avoid erosion due the abrasive nature of coal, just like firing diesel or heavy oil. According to the literature, 1.8 -2.2 tons of CWS is equal to 1 ton of Heavy fuel oil (HFO) and it costs about the same. It cost only US$ 62 million to retrofit an existing coal-fired power plant with CWS system and the yearly savings are estimated at US$ 41 mil per year, an attractive rerun on investment.

The beautiful aspect of this method is it generates Hydrogen rich Syngas according to the following chemical reaction.

2C + O2+2 H2O ——– 2H2+2 CO2 when the mixture is subject to Gasification instead of mere Combustion.

The combustion efficiency is about 96-99% and the boiler efficiency of more than 90%. It generates less Sulfur dioxide and Nitrogen oxide emissions and good for the environment compared to conventional coal-fired power plants. It is a good technology that needs the attention of Governments especially India, China and Indonesisa.Even coal rich countries like US, Australia should focus on this technology apart from their persuasion such as carbon sequestration.

In fact this will open new avenues for India and China to switch over to Hydrogen economy without making large investments. The coal water slurry fluid has a property similar to a Hydrocarbon as shown below.

Density 65-70% ,Viscosity -1000Cp, Size d< 50 microns, Ash content <7, Sulfur<0.5%. It is easy to handle a liquid than solid coal. pulverized coal is pneumatically conveyed and fired in rotary cement kilns for so many years. There is nothing new about it. Similarly coal water slurry can be a game changer for  the power industry,  if it is combined with Gasification and combined cycle;  it will lead  into Hydrogen based power generation industry using Fuel cell such as Molten Carbonate Fuel cell (MCFC). I believe there is a clear opportunity for the Governments and private industries  to seriously look into CWS technology which I believe, is a ‘precursor’ for Hydrogen economy of the future.

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