Coal?

[coisinger]

Has anyone ever run coal in their batch rocket?

It seems to me, just presumption and based on the characteristics of burning coal, that after an initial burn of wood, adding coal to the firebox would produce gases that would be ideal to ignite in the burn chamber and riser.  

[peterberg]

As far as I am aware of, not tried yet. There has been talk about it but no experiments to date. In theory, it could be done since the batchrocket construction is a sideways gasifier in disguise. In summer 2015(?) I've had a long chat with a South African university guy about this particular subject but no feedback to date.

[coisinger]

I'd be very curious to see how efficiently it would burn.

[drooster]

In my not-yet-experimented opinion I suggest a limited amount of coal would work wonderfully well, but after the initial wood-augmented burn it would stall as the heat from coal gases is not enough to maintain the required draw : meaning a great big load of coal after the wood would not work correctly.
Coal will prolong the "batch" burn time (probably) but the amount of coal on the lowest layer would have to be controlled to get the most out of it.
(Really efficient coal/anthracite burners use forced air.)

[Jura]

I wish I never saw a coal fueled rocket stove in operation.

As a chemist with degree in coal and oil faculty I,m familiar with  the difference in composition of  fuels.

Coal as  a  precious, high density source of energy shall be allowed to be used in gasification plants with a proper treatment of flue gases, only.
(getting rid of sulfur dioxide as a main pollutant requires high investments and operational costs in desulfurization instalation)
 
I'm writting from a place where coal is relatively cheap, abundant and commonly used as fuel in a home stoves.


The smog caused by improper way of burning it leads to a pollution level of the one of nowadays'  Beijing and we are fighting to endorse a law prohibiting its usage in private stoves.

(unlikely to win with the kind of government  in power)

[SteveStuff]

That is a shame jura! So extreme burn temperatures of a properly running rocket will not burn off the sulfur dioxide? Im no chemist so school me please.

[Jura]

Mar 9, 2017 17:04:42 GMT -8 SteveStuff said:

That is a shame jura! So extreme burn temperatures of a properly running rocket will not burn off the sulfur dioxide? Im no chemist so school me please.

Uff.. as to schooling
I believe that teacher's primary role  is gaining pupils' involvement as the  fundamental  factor of a successful  process of acquiring  knowledge.  Having obtained that next task is driving his pupils minds toward paying proper questions and confirming or denying thus obtained results (not directly  but ...by another portion of question).

Therefore my dear pupils ;-) I'd like you to confirm or contradict the  belowes thesis.
Coal (not the C element) and wood do not burn.

it s so easy nowadays .
One does not  need heading to library and peruse over encyclopedia for hours. 

your first home work is to compare the physical and chemical composition of the fuels of interest.

Small tip: your search should return a phrase "volatile matter" which should encourage you in deeper diving in the topic

Bear in mind the constraints : we say everything is possible but.. requires time and... energy. (we are able to create sun on the earth  and we do ->it nuclear fusion)

Therefore it would be prudent to check what is the ENERGY needed to decompose the SO2 particle and .. how fast such reaction goes.  so TIME.

When we get know how (if) the process is feasible and what mechanism govers it we will take a second lesson on quantitative estimation of it

(the bell sound reverberates through the narrow corridors of our school and pupils flock out of the classroom to spent the break playing in  the early spring sun)

[bmeagle]

SO2 is a byproduct of combustion of sulphur, combustion temperature doesn't change that, exactly like CO2, if you have sulphur in the coal you will have SO2. Scrubbing SO2 from the exhaust gasses is very expensive.

[Jura]

u r absolutely right. 
I have mentioned it before:

"Coal as a precious, high density source of energy shall be allowed to be used in gasification plants with a proper treatment of flue gases, only.

(getting rid of sulfur dioxide as a main pollutant requires high investments and operational costs in desulfurization instalation)"

[codyfellman]

I agree with the point as one can not unnecessarily use the coal. With proper precaution, one can only use coal in the plant.