5 fossil

Where global coal reserves

asia and north america

where natural gas

asia north america equator

where oil

north america russia saudi arabia

Oil shale

an organic-rich fine-grained sedimentary rock containing kerogene from which liquid hydrocarbons can be produced

Peat: formation time and where

500 years north

Oil products

- Gasoline

- Diesel fuels

- Asphalt base

- Fuel oils

- Heating oils

- Kerosene

- Liquified petroleum gas

Liquified petroleum gas (LPG)

• Propane, butane

• Gaseous att atmospheric preassure but can be condensed into liquid state

• LPG vapour is denser thean air: leaking gasses can floe long distances from the source

Natural gas

• 95% methane

• Hagh caloric value

• Does nor require storage facilities on site

• No sulphur

Mixes readily with air without producing smoke or soot

Fossil fuel consumption: how many yeas left

Coal - 175 years att current consumption

Oil - 32 years at curent consumption

Natural gas - 43 years at current consumption

we are past peak oil

Advantages of fossil

• Large amounts of electricity can be generated in one place, at realtivley low direct cost

• Transporting oil and gas to the power stations is easy

• Gas-fired power stations are completley efficent and less poluting

• A fossil.fueled power station can be built alost anywhere

High energy density fuels that make them suitable for transportation and other aplications

Dissadvantages of fossil

• Air polution

• Contributes to global warming

• Acid rain due to SO2 and Nox emissions

• Healt effects

• Reduced harvest due to air polutants

• Enviromental risks due to mining

Depleation of limited resources

Removal of emissions at the source

• Before combustion

• Pre-treatment of fuels (reduce content of S, N, H2O and trace elements)

• Oil refineries (fuels optimized for combustion)

• During combustion

• Optimize combustion conditions (reduce formation of CO, CxHyOz, soot, Nox)

• After combustion

• Capture emissions (various after-treatment of exhaust gases)

• Catalytic cleaning (additional reaction steps, reduce CxHyOz, soot, Nox)

• Filters (particles

Before comustion - refining for less emissions

• Removal of sulfur from coal: fysical, chemical and biological methods

Removal of sulfur from oil: heat treatment in a refinery

During combustion - refining for less emissions

• Optimize combustion conditions to reduce formation of CO, CxHyOz, soot and Nox

To optimizze:

- Mixing of fuel and oxygen, recidense time, temperature

- Compatibility between fuel propertioes and combustion unit design

Handling of the combustion equipment is important

After combustion - sulfur removal

Exampel: wet scrubbers

• Commonly used

• Removes ca 90% of the sulfur

Example: SNOX process (combined removal of sulfur and NOX)

• Catalytic reduction of NO to N2 using NH3

• Catalytic oxidation of SO2 to SO3

Production of H2SO4

Particle removal

• Inertial or interception (more efficent with increazing particle size)

• Diffusion to a solid or liquid collection surface

• Charging of particles

- Cyclones

- Fabric filters

- Electrostatic percipitators

Scrubbers

CO2 reduction

• Using less energgy

• Using low-carbon energy sources

• Usin carbon-containing fuels without emitting CO2 to the atmosphere (CCS)

CCS:

• Oxyfuel

• Membrane separation from other gases

• Carbon dioxide scrubbing

Co2 stored as compressed gas

Conciderations:

- Decrased power plant efficency by aproximatlety 10-40%

- Captures about 80-95% of the carbon in exhaust gas

Increases the price on electricity by aproximatly 30-60%

BECCS

Bioenergy with CO2 capture and storage (BECCS) to produce negative CO2 emissions

CCS advantages

• Can continue to use conventional sources and existing infrastructure

• Could be a potential accepted solution for countries having large scale coal reserves (China Usa)

• Ccs ON BIOENERGY CAN GIVE NEGATIVE co2 EMISSIONS

CCS dissadvantages

• CCS is not a long tem solution since both fossil fuels as well as the CCS storage potental are limited

• CO2 may leak from the storages

Investments in CCS thecnology may take research funding from thaé development of renewable resources

BIochar

Oyrolysis = thermal decomposition of the fuel without oxygen present. Generates combustables gasese and char