Chapter 1: Fuels Flashcards
Fuel
A substance with stored energy which can be released relatively easily for use as heat or power. The stored energy can be in the form of chemical energy (e.g. coal) or nuclear energy (e.g. uranium)
Fossil fuel
A fuel made from organic matter of ancient origin which cannot be replaced as quickly as it is consumed. The main fossil fuels are coal, crude oil, natural gas and coal seam gas.
Biofuel
A fuel made from organic material of recent origin. This fuel can generally be replaced as quickly as it is consumed, The main types of biofuels are biodiesel, biogas and bioethanol.
Biodiesel
A fuel made from vegetable oil or animal fat, consisting of long-chain alkyl esters. Biodiesel is typically made by reacting triglyerides with an alcohol, typically methanol in the presence of KOH as a catalyst.
Biogas
A mixture of gases produced by the breakdown of organic matter in the absence of oxygen. Biogas consists typically mainly of a mixture of methane and carbon dioxide.
Cloud point
The temperature at which the diesel or biodiesel appear cloudy because of the formation of small crystals and thus begin to freeze. These crystals thicken the fuel and clog filters and fuel injectors in engines.
Coal Seam Gas
Natural gas trapped by pressure on the surface of a coal seam.
Enhanced Greenhouse Effect
The warming of the temperature of the Earth’s surface because of an increase in the concentration of greenhouse gases as a result of human activities.
Flashpoint
The lowest temperature at which the vapour of a liquid will ignite when an ignition source (such as a flame) is applied to it.
Fracking
The process of injecting sand, water or chemicals at a high pressure into coal or rock to release trapped natural gas.
Greenhouse Effect
The process by which heat radiation from the Earth’s surface is absorbed and then re-radiated by gases in the atmosphere. The greenhouse effect maintains the temperature of Earth at conditions which are suitable for life.
Greenhouse Gas
A gas which is able to absorb and re-radiate heat radiation. Tyese gases contribute to the Greenhouse Effect. Examples are carbon dioxide, methane and water vapour
Hydrogen Economy
A proposed system of delivering energy for society using hydrogen as the source of energy.
LPG
A mixture of propane and butane that is separated from natural gas or crude oil. It is stored under pressure to liquefy the propane and butane.
Natural Gas
A fossil fuel comprising mainly methane which exist in the gas phase under the conditions in which they are extracted from Earth.
Bioethanol
A biofuel made by converting starches from plants into sugars using enzymes and then fermenting the sugars to ethanol using yeast.
Renewable
Renewable resources are not in limited supply (e.g. wind, power) or can be replaced as quickly as they are consumed (e.g. biofuels such as biodiesel, biogas, bioethanol).
Petrodiesel
Diesel fuel derived from crude oil by fractional distillation.The composition of petrodiesels varies, but is generally around 75% alkanes and 25% aromatic hydrocarbons. The size of the hydrocarbons range from C10 to C15.
Shale Gas
Natural has which is trapped underneath shale rock deposits, usually will below the Earth’s surface.
Energy Transformation
The process of converting one form of energy into another form of energy (e.g. heat energy into mechanical energy).
Fractional Distillation
The separation of the components in a mixture on the basis of their boiling temperatures.
Non-renewable
Non-renewable energy resources are those which are being used at a faster rate than they are being replaced.
