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Exercise 2. Write a summary of the text. Translate your summary into Russian.



 

Exercise 3. Find information about Clean Air Act, Clean Water Act and similar regulations in Kazakhstan. Be ready to discuss it.

 

Text 6.

Clean coal

Almost exclusively used to refer to carbon capture and sequestration technology (CCS), Clean coal is an umbrella term used primarily to describe technologies that may reduce emissions of carbon dioxide (CO2) and other greenhouse gas that arise from the burning of coal for electrical power. Typically, clean coal has been used by coal companies in reference to carbon capture and sequestration, which pumps and stores CO2 emissions underground, and to plants using an Integrated gasification combined cycle which gasifies coal to reduce CO2 emissions.

 

Clean coal technology

The US Department of Energy continues to work with private industry to develop carbon capture and sequestration technologies. Several methods are available under this technology including pre-capture, oxy-fuel combustion, and post-capture CCS. Perhaps the most popular example of a coal-based plant using (oxy-fuel) carbon capture technology is Vattenfall’s Schwarze Pumpe plant in Germany. However, it has not yet been demonstrated that carbon stored underground will be able to stay there indefinitely. Another technology under development is Integrated Gasification Combined Cycle or IGCC.

Other carbon capture and sequestration technologies include those that dewater low rank coals. Low rank coals often contain a higher level of moisture content which contains a lower calorific content per tonne. This causes a reduced burning efficiency and an increased emissions output. Reduction of moisture from the coal prior to combustion can reduce emissions by up to 50 percent.

 

Clean Coal and the environment

According to the United Nations Intergovernmental Panel on Climate Change, the burning of coal, a fossil fuel, is blamed for climate change and global warming. As 25.5% of the world's electrical generation in 2004 was from coal-fired generation, reaching the carbon dioxide reduction targets of the Kyoto Protocol will require modifications to how coal is utilized.

Sequestration technology has yet to be tested on a large scale and may not be safe or successful. Sequestered CO2 may eventually leak up through the ground, may lead to unexpected geological instability or may cause contamination of aquifers used for drinking water supplies. There are also concerns that plans to pump some of the sequestered CO2 into certain oil and gas reserves, to help make the fuels easier to pump out of the ground, will lead to increased concentrations of CO2 in potential fuel supplies. This would have to be removed or released during the refining process.

 

Byproducts

The byproducts of coal combustion are considerably hazardous to the environment if not properly contained.

While it is possible to remove most of the sulfur dioxide (SO2), nitrogen oxides (NOx) and particulate matter (PM) emissions from the coal-burning process, carbon dioxide (CO2) emissions and radionuclides will be more difficult to address.

 

Words to know:

1. carbon capture and sequestration technology

2. pumps

3. pre-capture CCS

4. oxy-fuel combustion CCS

5. post-capture CCS

6. aquifers

7. particulate matter

 

Exercise 1. Explain the meaning of the following word combinations:

dewater low rank coals, calorific content per tone, global warming, refining process

 







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