Ethanol as a Fuel?

[cwes99_03]

Let me restate this

 

Potential problems with the use of butanol fuel

The potential problems with the use of butanol are similar to those of ethanol:

 

To match the combustion characteristics of gasoline, the utilization of butanol fuel as a substitute for gasoline requires fuel-flow increases.

Alcohol-based fuels are not compatible with some fuel system components.

Alcohol fuels may cause erroneous fuel quantity indications in vehicles with capacitance fuel level gauging.

The viscosity of butanol is much higher than for gasoline or ethanol, which could have negative effects on the fuel system.

 

Fuel to air mixture is not the only problem.

 

Since you didn't understand this the first time, I'll have to explain it.

 

Fuel flow increases - the pump has to increase fuel pressure to the injectors.

alcohol fuel - butanol has the same corrosive problems with rubber and other parts found in most pre 2001 vehicles as ethanol, as well as cause false readings on capacitance based fuel level monitors

viscosity - n-butanol does not flow through a pipe as easily as gasoline and ethanol, generally stated it is "thicker". This means that the pump has to work harder to even get the fuel to move, and the injectors will not atomize the fuel as easily.

 

Put these things together and you get 1) lots of parts need to be replaced because butanol will corrode them just like ethanol and 2) you have to replace the pump with a higher pressure/higher capacity pump and the fuel lines with higher capacity lines to get the fuel to the injectors, and you have to replaced the injectors with injectors capable of atomizing a more viscous fluid.

[gribbon]

There are several types of bio fuel which we haven’t yet discussed.

 

Methanol

Syngas

GTL/BTL

Burning metals etc in engines (there was an article in New Scientist ages ago about burning Nanoparticles of Iron/Boron etc in ordinary engines.)

 

But anyway….

 

According to Wiki, these are the theoretical advantages and disadvantages.

 

Methanol economy advantages compared to hydrogen:

 

· efficient energy storage (by volume) and also by weight when hydrogen confinement vessel taken into account.

 

· required hydrogen infrastructure would be prohibitively expensive; methanol can be directly cycled into existing gasoline infrastructure

 

· can be blended with gasoline

 

· user friendly (hydrogen is volatile and requires high pressure system confinement)

 

· methanol serves as a raw material for the chemical industry

 

 

Methanol economy advantages compared to ethanol

 

· can be made from any organic material using the proven Fischer Tropsch method of synthesis gas catalysis

 

· can compete with and complement ethanol in a diversified energy marketplace

 

Problems with it

 

· high energy costs associated with generating hydrogen needed to make it

 

· presently generated from syngas still dependent on fossil fuels (although in theory any energy source can be used).

 

· energy density (by weight or volume) one half of that of gasoline

 

· corrosive to aluminum, importantly aluminum parts in engine fuel-intake systems

·

hydrophilic: attracts water, which can create solid jelly-like obstructions in fuel-intake systems (in cold weather), which is corrosive, and which can separate into a non-combustible component

 

· methanol, as an alcohol, increases the permeability of some plastics to fuel vapors (e.g. high-density polyethylene). [2] This property of methanol has the possibility of increasing emissions of volatile organic compounds (VOCs) from fuel, which contributes to increased tropospheric ozone and possibly human exposure.

 

· low volatity in cold weather: methanol-fueled engines can be difficult to start, and they run inefficiently until warmed up

 

· Methanol is generally considered a toxin but methanol toxicity is actively researched [3]

 

· methanol is a liquid: this creates a greater fire risk; unlike hydrogen and other gases, methanol leaks do not dissipate

 

· methanol accidentally released from leaking underground fuel storage tanks may undergo relatively rapid groundwater transport and contaminate well water, although this risk has not been thoroughly studied. The history of the fuel additive methyl t-butyl ether (MTBE) as a groundwater contaminant has highlighted the importance of assessing the potential impacts of fuel and fuel additives on multiple environmental media. [4]

 

Beyond that....

 

"Crops with higher yields of energy, such as switchgrass and sugar cane, are more effective in producing ethanol than corn. Ethanol can also be produced from sweet sorghum, a dryland crop that uses much less water than sugarcane, does not require a tropical climate and produces food and fodder in addition to fuel.

 

Environmentalists have objections to many modern farming practices, including some practices useful for making bioethanol more competitive ("factory farming"). If more third-world land were to be converted to agriculture to feed ethanol fuel demand, there is the possibility of trading today's automotive pollution for tomorrow's farm pollution.

 

- There is some potential that through irresponsible farming methods some rainforest areas could be cleared to make land available for growing crops for commercial commodities such as palm oil for the generation of biodiesels."