BobMac and Kristijan just a comments on the in-engine side of it.
The nitrogen and CO2 gasses absorb heat modifying the combustion characteristics of the combustible gases. The molecules of the non-combustible also interspace holding the combustible molecules apart.
Now using the Stirling engine as the “enclosed” gas expansion engine. Different results can be had using different expansion (and in the Stirling - contraction) gases and gas mixes.
Internal combustion engine operate and power by any of the internal gases EXPANDING. The internal made heat providing the gasses energized expansion.
We need some inert’s in the cylinder expansion gases mix to moderate things or you will be producing too fast of reactions; damaging pressures spikes; and damaging heat.
Yes Steve, I have been pondering this in my head since yesterday. Thanks for explaining this with engine combustion and needing protection for the metal parts and for good engine operation. Inert gases like Nitrogen is needed as a buffer here too. Not just in the gasifer. So the needed Nitrogen is also introduced with the fresh air at the mixer going into the engine with the wood gas.
Bob
Rindert, look up blau gas.
We still have the foundations where the benches were for our blau gas plant here in Calumet.
It worked like this… They burned coal and heated up steam to a superheated temperature and then shut off the air to the coal and sprayed the superheated steam on the coal embers. The coal had to be orange hot. The incandescent coal and superheated steam made the reaction that you’re talking about. It’s called the water gas shift.
Because it was a batch process they had a series of converters working together on a bench. We had several benches in our plant here. We still have the slag pile and it’s a super fund to clean up site.
It’s definitely a better gas, but they didn’t compress it. It still was stored in those big gas holders over water.
Bob,
Just saying… nitrogen is not inert. In the presence of oxygen and high heat it makes nitrous oxide or nitrogen dioxide both of which are pollutants.
The triple bond in a nitrogen compound is the most unstable releasing the most energy which is why most explosives are made with some sort of nitrogen triple bond.
Okay Matt correct me if I am wrong, if we heat the water first using the wasted engine exhaust then it would use less calories of heat inside the gasifer firetube to make this flash water vapor on the hot lobe of charcoal that would displace the Nitrogen coming in with the incoming air, right?
If we preheat the incoming air all the better. right? We are trying to keep the gasifer as hot as we can to do this work. We should also be keeping the firetube as hot as we can by insulating it to hold heat after preheating the incoming air that will be coming through the nozzles with Nitrogen mixed with it.
The expanded incoming air has less Nitrogen in it by its expanded volume. right?
So Now if you take H2O and use wasted exhaust from the engine to make steam there is no Nitrogen in the steam. right? And this would be more efficient in making Hydrogen because it would displace the Nitrogen if it was introduced into the incoming air stream at the nozzles or nozzle.
Like you said earlier when you said that the water will displace the Nitrogen when it hits the hot charcoal lobe. I would think that this steam would be more effective and efficient because we are using a wasted source of heat from the engine so it will take less calories to do this work. Win, win. Being It from DOW or stationary generator engine exhaust system. Steam can be regulated when it is in a vaccum state using a brass control valve manually or automatically.
I like this, we can not get rid of all the Nitrogen but we can cut back on its effects with control and then add it back at the mixing of wood gas to air ratio 1: 3 instead of 1:1 ratio. Making a Richer gas to burn in the engine. And it is safe for the engine.
I know I am going on and on but this is just a little faction of what I have processing in my brain and put on paper.
Do you see what I have to live with all the time, it keeps me awake at nights thinking. And I am thinking on a lot of different subjects all the time. I know I am not the only one that experiences this on this DOW site. I will need a nap later on today.
Bob
Yes Bruce, you are correct, only when the gas is in a vaccum with no moisture or air can we call it a true inert gas. We use this Nitrogen gas in our 500 kv circuit Breakers in the switch yard where I worked at for 35 years. It works great in puting out a high voltage arc flash inside the break. But only in a Nitrogen atmosphere. I might add that after we pulled the negative atmosphere to remove the moisture and any other oxygen and other gases, we would add Nitrogen and keep the breakers always at a positive Nitrogen levels for operation of the Breakers. Thank for correcting me and the extra information on nitrogen gas.
Bob
Yes Rindert but dont take 1100c in to the calculation! Like l sayd the reaction only happens over 800c and even then quite slowly. So in best case scenario you have to take 300° in to the calculation, that is ^T. Your calculation is then only rouhlghly a third of a actual power demand. Drawing 40hp on a engine for making nitrogen free gas will never give back enaugh reward…
That 1100c you mention is the target reaction temperature actualy. Higher is ofcorse better chemicaly speaking but in my opinion water gets “cracked” good enaugh at this temp and slag is not yet formed. Anything cooler thain that the reaction is slugish and incomplete.
In a gasifier things work because we constantly add in energy by partialy burning the carbon. This constantly provides energy for the endothermic reaction.
What you say about the ratio is true. 1 pound of char can crack 1 pound of water, roughly, in a ideal world.
Excuse my tired brain, this is not gonna be a precise calculation. Up you see how energy demanding the reaction is. Roughly 1/3 the energy of burning carbon with oxigen completely to CO2 and 1/2 the incomplete oxidation to CO.
So, just from some before bed calculation, for every 50l (2 moles) of water gas produced, you need 130kJ of energy to drive the reaction. Doesent sound much till you realise its 1 mole of water that needs to carry all that energy! So, in order to produce 2 moles of gas, 1 mole of water is neaded. Thats 18g. Hit 18g with 130kj and the temperature required to do that is 3600c. Plus, we need to add the 800c of “dead weight” under wich the reaction stops, but steam still needs to be heated to the point nevertheless! And thats not taking in to a count the energy needed to vaporise steam, but admitedly that culd ne done via exess heat…
Unfortunaly its beond our current abilitys l suppose…
Yes thats why I have a CAD system. If I dont get ideas out of my head and into model space I will not sleep. Same with writing code I will stay up for days like a meth head writing code: so I dont forget what I am going write 50 lines ahead of where I may be at.
Ok I have not done pre steam injection yet. Using the exhaust is a good idea but for me it is too complex to implement. Complexity adds cost and we need to do this cheaper. So not that it is a bad idea its just too much for me to implement into a product.
However, in the reactor I am developing it uses those cast reducers like before. However there is a chamber that surrounds the smaller choke end. This is where all the heat will be directed internally so plenty to give off here. Water drip here and flash to steam (my intent anyways) and then it will migrate into the air intake stream. Ok so now our engine is sucking in what ever volume say 300 cfm. If this flash steam process is producing 100 cfm steam we reduce the atmosphere coming in to 200 cfm. Add more steam the further this will reduce. Now there is a point where there will not be enough oxygen to oxidize the charcoal and things will crash. There is 75% nitrogen in our atmospheric air, so we can cut a lot of it out. So we can keep adding more steam while maintaining enough oxygen input to keep the reactions going. This is not my goal right now, right now Im just trying to develop this reactor core first.
Ok now direct water drip, In my experience the water drip it simply drains into the nozzle and migrates into the oxidation zone. It is not flashing to steam inside the nozzle. So the air intake is not effected by steam expansion and is not displaced. When the water does reach the end of the nozzle my theory here is: it is then flashing to steam. This I think is doing a few different things. One it is absorbing heat in the transition to steam and it is also creating a barrier in this process between the oxidation zone and the nozzle tip.
Now in either case steam first , steam after, if we introduce less Nitrogen, the gas will be richer, the engine will need less, thus slowing down flows. You will burn less fuel as you increase the amount water shift to hydrogen. Think about what I just said here, this changes a lot of internal dynamics of all the processes here. This will go very deep if someone try it. This changes your dwell times, the endothermic / exothermic reactions will change and be more efficient and number of others things.
If you think an idea will work dont let anyone of us here deter you from trying it. Until you actually build it we will never know. Dont throw away ideas because some smarty pants told you it wont work. Think outside the box! One little change might make something viable where the original idea wasn’t and a lot of times there are things that are not accounted for or were unforeseen that can change your outcome good or bad. Or you build on it, generally a concept will lead to further development and broader viable concepts.
Build a proof of concept. You can cheat here, for instance use something to heat the water and super heat the steam that you can get readily available. use a pot or something and inject that steam into a small hole and try to light the top of the pot. If it works you have proof of concept. Now you build on this concept. How are you going to produce the steam and make it a part of the system. It will need to be self sustaining right? You need to make charcoal for the process right? How can you make the charcoal and produce the super heated steam in that process. I’m pretty sure you can achieve this no problem.
Wheew!!! I didn’t mean to stir up a hornet’s nest.
Thanks Kristijan for chemistry information. I will have to get my old organic notes out.
I was talking to a friend who was a boiler’s mate in the Navy on Friday. He reminded me about the broomsticks getting cut off.
Rindert
My post in only a friendly word of advice to anyone. I see ideas get kick around and I see ideas shot down. Take the good and leave the rest is all Im saying. My tone couldnt be any friendlier.
Hi Rindert, Some of my Dam Operators friends that came from the high pressure steam generation plants down south. They told me about how they would go out and check for leaks with a broom stick. You can hear it but you can’t see where the leak is coming from. Dangerous stuff.
Bob
Any calories of heat lost from the gasifer and not being a part of the prosses of helping making the change going through the charcoal bed, restriction opening and the reseve charcoal, is a lost of a chance for calories of heat to be used to change H2O into 2 Hydrogen to a gas. By using the 1 Oxygen of H2O.
Now if the heat calories are recycled to the H20 preheating or the needed preheated air coming into the charcoal hot lobe. It is not wasted but it is used for the prosses of the finished product.
Is it possible to not lose any heat on the outside of a gasifer or at least get it down to a minimum amount to where I can hold my hand on it and not have to remove it.
On my gasifer I can not hold my hand on the outer barrel of the lower part of the firetube for more then 3 or 4 seconds. It does not burn the regular black paint off but it is hot. To me this is wasted heat calories going into the atmosphere. This heat could of been used to pre heat the incoming air to the gasifer or air going to the engine to be filtered through a paper filter at lease to clean the soot out the wood gas so it can go into the engine of a new vehicle and out through the Cadillac converter with out plugging it up.
My present WK build is going to address this wasted heat calories and put it back to use some how. Hopefully in making more Hydrogen gases.
Bob
It was not my intention to shut down a inovative idea. I laugh the hardest when someone says to me “if it works, why dont anyone use it?”. Probably everyone here knows lm first in line to try out crazy ideas l just want to throw my 2c in the bank of knolidge, and wuldnt speak if l wuldnt be sure or wuld mark my statement as “l am unsure”.
Guys,
I’m ready to drink that with your idea to get a high-calorie gas without nitrogen, you all will fail! . Firstly, the production of such a gas is possible only under two conditions, and secondly, these conditions are rather difficult to organize at home, especially for your needs in the volume of gas … So the first condition is steam-oxygen supply to the gas generator, which can only be organized on a large scale, for example at a chemical plant … the second condition is even more difficult: the so-called six-phase blowdown of the gas generator is needed and, accordingly, a complex production cycle with a huge amount of gas produced …
I have made nitrogen free water gas at home by superheating charcoal (no oxigen just some electricity ) and passing steam trugh it. It was for my graduation asignment, making a Fischer Tropsch reactor. It absolutely can be done at home. But is it worth the effort and energy investment? Absolutely not! When someone comes up with that we will drink together
I do not have the knowledge or skill of the engineers that improved water gas systems 150 years ago . The limit was not the practicality but the economics . These systems were only economical in France because of tariff on imports before WW I , In United Kingdom system operated that was fueled by kelp , tangle , seaweed , that washed up by tens of tons on shore but was replaced by coal or oil . Use of gasifiers was renewed by WW 2 .
l just want to throw my 2c in the bank of knolidge, and wuldnt speak if l wuldnt be sure or wuld mark my statement as “l am unsure”.
. Firstly, the production of such a gas is possible only under two conditions, and secondly, these conditions are rather difficult to organize at home, especially for your needs in the volume of gas … So the first condition is steam-oxygen supply to the gas generator, which can only be organized on a large scale, for example at a chemical plant … the second condition is even more difficult: the so-called six-phase blowdown of the gas generator is needed and, accordingly, a complex production cycle with a huge amount of gas produced …
) and passing steam trugh it. It was for my graduation asignment, making a Fischer Tropsch reactor. It absolutely can be done at home. But is it worth the effort and energy investment? Absolutely not! When someone comes up with that we will drink together