Environmental Friendly Coal Power Plants

Presented By: Mohammad Faizan Abdul Haseeb

Submitted to: Dr Sajid Saleem

GSESIT-FEST Hamdard University

Capture harmful gases from exhaust of thermal power plants

With different techniques valuable by products are obtained

Handling remaining gases safely

OBJECTIVES

World Electricity Production Sources

Fossil Fuel Reservoir

RENEWABLE NON RENEWABLE

Biomass and Solid Wastes COAL, Oil and Gas

Emits: CO2, CO, NOx, heavy metals, dioxines

Emits: CO2, SO2, NOx, Mercury .

Carbon emissions from burning biomass is more dangerous than fossil fuel energy resources.

About 41.3% of world total energy is get from Coal. As compared to oil and gas COAL released more CO2

TYPES OF THERMAL SOURCES

Green House Gasses

Acid Rain

NOx (NO Nitric Oxide & NO2 Nitrogen Dioxide) Its form from Nitrogen Gas and Oxygen gas during Combustion

specially at High Temperature Causes 1) Acid Rain

2NO2 + H2O → HNO2 (Nitrous acid) + HNO3

3HNO2 → HNO3 (Nitric Acid) + 2NO + H2O

4NO (Nitric Oxide) + 3O2 + 2H2O → 4HNO3

4NO2 + 2H2O + O2 → 4HNO3

2) SMOG(FOG)

NOx (Nitrogen Oxides) Effects

It is Toxic Gas Sulfur dioxide is the product of the burning of

sulfur or of burning materials that contain sulfur:

S + O2 → SO2

Causes Acid Rain SO2 (g) + H2O → SO2·H2O SO2·H2O → H+ + HSO3

−

HSO3 → − H+ + SO32−

SO2 (Sulfur Dioxide) Effects

Its usually form during combustion process: CH4(methane) + 2O2 → CO2+ 2H2O C(Coal) + O2(g) → CO2(g)

It is a main source of Green House effect Its also source of Ocean Acidification since

its dissolve with seawater to form Carbonic Acid

CO2 (Carbon Dioxide) Effects

The process removing of pollutant gases from power plant/industry exhaust system is called Scrubbing.

Two major types of Scrubber

Wet Scrubber:In a wet scrubber, the polluted gas stream is brought into contact with the scrubbing liquid, by spraying it with the liquid, by forcing it through a pool of liquid, or by some other contact method, so as to remove the pollutantsDry Scrubber:This type of Scrubber filter is accomplished by firing a series of dry ingredients or Electrostatic precipitator (ESP) or fabric filter at high speeds into the gases to neutralize pollutants

SCRUBBER

It cleans about 90% of harmful gases that are produced due to Coal burning and make their by-products.

The plant products following by-products from Coal combustion:

1. Gypsum [Used in Fertilizer and soil conditioner]2. Nitrogen Gas [Used in aircraft tires]3. Mercury [ Used in fluorescent lamps]4. CO2 [ Used in Oil recovery]

5. Water Vapors [Used as recycled water]6. Ash [Used in making concrete and road material]

CLEAN COAL TECHNOLOGY

The input to the power plant is a renewable energy source which may include wood, agricultural waste, crops, animal waste and last but not the least our sewage waste.

The Thermal processes of Bio Mass and Waste mass is nearly same as Coal combustion but it some more harmful gasses and heavy metals.

After combustion the flue are treated with the active carbons that remove Dioxins, Furan and Heavy Metals

In next stage HCL scrubber is used to remove acids

Biomass & Waste Mass Power Plant

Flue-gas DesulfurizationIn this chamber sulfur dioxide is converted into solid sulfur which is then sent to the scrubber.

The waste gases we obtain are equally Not harmful.

Flue gas Desulfurization of done by using ‘Fluidized Bed Combustion’(FBC) this separate SO2 to form Gypsum(CaSO4.2H20) and also efficient the transfer of heat.

Nitrous Oxide is treated with Ammonia which make Nitrogen Gas and Water Vapor

Mercury can be extracted using Wet Scrubber

Ash remove by Electrostatic precipitator (ESP) and Wet Scrubber processes

EXTRACTION OF BY-PRODUCTS

Amine (organic compound) used to capture Carbon Dioxide (CO2)

Slag: Used in concrete HCL: use in industry Scrap Iron Non Ferrous Metal: Aluminum, Copper,

Brass etc

EXTRACTION OF BY-PRODUCTS

The Thermal Power Plant may design as Cogeneration Power Plant to generate Electricity and useful Heat (Water Steam)

Consolidated Edison (USA) provide biggest steam service produces 66 billion KG of 180o of steam per year

Cogeneration is still common in pulp and paper mills, refineries and chemical plants

Hot Steam Utilization

Carbon Dioxide (CO2) is used in number of uses link beverages, fire extinguisher etc

Large amount of CO2 remain unused which causes Green house effect is out in the environment

The CO2 is carefully treated and store/sequestration

The processes of handle CO2 is known as Carbon Capture and Sequestration (CCS)

WHAT ABOUT CO2

Carbon dioxide (CO2) capture and sequestration (CCS) is a set of technologies that can greatly reduce CO2 emissions from new and existing coal- and gas-fired power plants and large industrial sources. CCS is a three-step process that includes:

1. Capture of CO2 from power plants or industrial processes

2. Transport of the captured and compressed CO2 (usually in pipelines).

3. Underground injection and geologic sequestration (also referred to as storage) of the CO2 into deep underground rock formations. These formations are often a mile or more beneath the surface and consist of porous rock that holds the CO2. Overlying these formations are impermeable, non-porous layers of rock that trap the CO2 and prevent it from migrating upward.

CARBON CAPTURE AND SEQUESTRATION

Carbon dioxide (CO2) capture and sequestration (CCS) could play an important role in reducing greenhouse gas emissions, while enabling low-carbon electricity generation from power plants. As estimated in the U.S. Inventory of Greenhouse Gas Emissions and Sinks , more than 40% of CO2 emissions in the United States are from electric power generation.

At present CSS dramatically reducing CO2 emissions (by 80-90%) from power plants that burn fossil fuels.

Applied to a 500 MW coal-fired power plant, which emits roughly 3 million tons of CO2 per year,  the amount of Green House Gases emissions avoided (with a 90% reduction efficiency) would be equivalent to:

Planting more than 62 million trees, and waiting at least 10 years for them to grow.

CCS IMPORTANCE AND END USES

That means Planting of such a massive amount of trees and waiting at least 10 years for them to grow is something that cannot be done overnight but through CSS it can be accomplished. YES THIS IS AWESOME AND PROMISING!!!

Avoiding annual electricity-related emissions from more than 300,000 homes.

CCS could also viably be used to reduce emissions from industrial process such as cement production and natural gas processing facilities.

 End uses of CO2 include enhanced oil recovery (EOR), food and beverage manufacturing, pulp and paper manufacturing, and metal fabrication.

Importance and End Uses- continued

Post- combustion capture• Here flue gas reacts with chemicals that absorb CO2

and then heat the chemicals to release CO2.

NOTE: Flue gas : Mixture of nitrogen ,water vapor and 15 % of Carbon dioxide

CARBON CAPTURE TECHNOLOGY

Oxy-fuel combustion◦ Use of pure oxygen to support the fossil fuel

combustion. The flue gas is then mostly CO2 and water making it to separate easily.

CARBON CAPTURE TECHNOLOGY

Pre- combustion capture Removing of carbon before combustion. By gasifying

the coal through the reaction with more oxygen, it is possible to mix of

mostly CO2 and

hydrogen.

CARBON CAPTURE TECHNOLOGY

Many point sources of captured CO2 would not

be close to geological or oceanic storage facilities. In these cases, transportation would be required.

The main form of transportation ◦ Pipeline◦ Shipping

TRANSPORTATION

• Geological storage

• Oceanic storage

CARBON STORAGE TECHNOLOGY

GEOLOGICAL STORAGE

In a study it is found that when CO2 is injected into basalt, it eventually turns into limestone -- essentially converting to rock.

Two storage mechanism has been proposed

• Dissolving CO2 at mid-depth.

• Injecting the CO2 at depths greater than 3 km , where it would form lakes of liquid CO2 . Below 3 km liquid CO2 would be denser than sea water and would sink to the ocean floor.

OCEANIC STORAGE

Geochemical Monitoring Seismic Monitoring

Non-Seismic Monitoring

MONITORING OF STORED CO2

WHAT MIGHT CARBON CAPTURE AND STORAGE LOOK LIKE?

The diagram is from a BP news release from the abandoned Miller project, UK North Sea.

CCS technologies actually require a lot of energy to implement and run transporting captured CO2 by truck or ship, require fuel.

Creating a CCS-enabled power plant also requires a lot of money.

What happens if the carbon dioxide leaks out underground?

We can't really answer this question. Because the process is so new, we don't know its long-term effects. Slow leakage would lead to climate changing. Sudden catastrophic leakage is dangerous, and causes asphyxiation.

The more CO2 an ocean surface absorbs, the more acidic it becomes, higher water acidity adversely affects marine life.

CARBON STORAGE CONCERNS

http://www.geos.ed.ac.uk/sccs/storage/storageSites.html

http://network.carboncapturejournal.com/video/2018151:Video:4342

http://www.futuregenalliance.org/about.stm

CCS Implemented Projects