Zusammenfassung der Ressource
Natural
Gas
- General Info
- Deal with NG
Associated with Oil
- flaring
- injected into reservoir
to maintain pressure
- First found 19th century associated with oil production
- Composition
- Sat, Aliphatic hydrocarbons
- straight chain
- greatest proportion methane > 50%
- Melting point –
182.5 °C
- Boiling point –
161.6 °C
- ΔHc° = - 882.0
kJ/mol
- Colourless
- Alkanes with up to C6
- branched alkanes
- Unwanted
- Gases CO2/H2S/N2/Hg
- H2O+Salt
- Mercaptans CH3SH
- detect leaks to distinct smell
- Type
- Wet < 85% C1
- Dry almost C1 Natural or
purified
- Liquid Natural
Gas for easy
Transportation
- Reduce V to 600 fold @
-162 oC
- Aluminium container and Hg Below
level of detection and No water
- Used for
- Domestic –
Heating and
Cooking
- Commercial –
Heating, transport
fuel, etc.
- Electric
Generation
- Industrial
- Critical Industrial Reactions
- Steam Reforming
- CH4 + H2O ==>CO + 3H2 – syn gas
- Highly endothermic 900 °C @at high pressure
- Tubes are heated in a furnace
- Water – gas shift
- thermodynamically favoured by low temperatures
- CO + H2O ==>CO2 + H2
- ُُEquilibrium reaction
- Industrially
- High Temperature Shift
- iron oxide catalyst
- Low Temperature Shift
- CuO/ZnO/Al2O3
- Fischer – Tropsch
- 2n H2 + CO ==> -(CH2)n- + H2O
- Steam Reformation products enter the reactor
- catalyst Iron or Cobalt
- Products
- Olefins / Alkenes
- Paraffins / Alkanes
- Oxygenates
- Aromatics
- Methanol synthesis
- Ammonia synthesis
- N2 + 3H2 ==>2NH3
- Fe catalyst
- reaction is exothermic
- favoured by low temperatures
- high pressures
- A substance that promotes
the rate of reaction by
providing an alternative
reaction pathway, and is
regenearated at the end
- Homogeneous Catalysts
- Same as the reactants gas
or liquid
- Not common/Hard
to separate
- Examples are
use of KOH
- Heterogeneous Catalysis
- different phase as
the reactants solid
- Common, as
separation is easy
- Combustion of Natural Gas
produce CO2 and water
- Advantages of Burning
Natural Gas
- Fewer emissions
- Reduced sludge from
scrubbing SO2
- Gas Burn is
determined by
- CV , measure of heat released
when it is burnt. Measured
normally in Btu’s
- Wobbe Number =(Calorific
Value)/√(Specific Gravity)
- same wobbe number ==> same
amount of heat
- SG, much gas will pass through the
orifice of a burner in a set time at a
given pressure
- Burning Velocity Measures the
speed at which a flame is
propagated in a gas
- Burning Gas problem
- Light Back
- unstable flame
- low flame speed gas