[Stoves] Off Grid Pellitizing issues --- was Re: Bulk density of LPG vs pellets

Fri Feb 16 11:35:33 CST 2018

There are definite benefits to dried and densified but capital costs for even small scale densification systems are often out of reach for most communities but they continue to be installed and eventually abandoned for ack of maintenance budget. It seem to be the business organization part is the hardest to pull off in most countries.  

As Christa suggests any mechanical fuel processing or energy systems requires what we used to call “technical culture” – the ability or operate and maintain mechanical systems. I have found that diesel mechanics often have the right combination of skills to run and maintain a gasifier or a small sawmill. Boilers and turbines require another level of organization to keep them running in the developing world. There are many examples in Asia, SE Asia, and Africa of systems that run milling operations during harvest for rice or processing of feeds and foods. So far ORC systems have been too expensive, too complex, and too low efficiency for the amount of power they produce. Most of the ORC systems in the US are publicly subsidized. There are many in Europe which take advantage existing hot oil boilers in operation and very high incentive prices for power. In that context adding the turbine is a sensible means of recovering heat. We looked at recovering gas from charcoaling in SubSahara Africa for conversion to power. A lot of work on energy recovery from charcoal making has been done in Brazil. In all cases it requires an “industrial” or business setting that doesn’t match the traditional earth kiln production in SSA. So we’re still looking for a fit.

Tom

From: Stoves [mailto:stoves-bounces at lists.bioenergylists.org] On Behalf Of Law, Steven (MOECC)
Sent: Friday, February 16, 2018 7:20 AM
To: Discussion of biomass cooking stoves <stoves at lists.bioenergylists.org>
Subject: Re: [Stoves] Off Grid Pellitizing issues --- was Re: Bulk density of LPG vs pellets

In reply (see underline):

Steven, 

do you know of any of the systems you propose that are a bit fuel flexible when it comes to moisture content and particle size of the biomass input? 

and that can be run without an engineer on standby?

REPLY: the technology set up of a biomass combustion (low pressure) hot water boiler paired with an organic rankine cycle (ORC) power generation module is more robust as the combustion system can be designed to be more forgiving on lower fuel quality.  

Both the biomass combustor and ORC can be mostly automated in their operation, so only a low skill technician is required onsite and an internet connection is also required so the devices can be monitored remotely by a highly skilled technician/engineer at a central location, but no engineer is required to be onsite except for routine preventive maintenance, etc. 

For some examples of this concept see the website: https://electratherm.com/applications/biomass-systems/

what I have seen in African contexts so far, especially on the gasifier / internal combustion engine set-up, is a graveyard of clogged-up engines, due to lack of gas scrubbing and/or inconsistent feedstock. They do work theoretically but I haven’t seen them in prolonged practice in countries where local languages don’t have a term for ‚preventive maintenance‘ .

would love to hear of some success stories of any kind of ongoing continued operation. 

those are the challenges I see before they can become win-win-scenarios.

REPLY: the gasifier / internal combustion engine set up is very fussy about syngas cleaning and the overall maintenance requirement is very high. There are systems now operating in Europe successfully but the biomass fuel quality is very stringent; some are even running on wood pellets as one approach to resolve the fuel quality problem. Getting wood chips to such a high consistent quality is also easier said than done, but it is possible when the money is spent to make it happen.

For some examples of this concept see the website:  <http://fee-ev.de/11_Branchenguide/2018_Industry_Guide_Biomass_Gasification_EN.pdf> http://fee-ev.de/11_Branchenguide/2018_Industry_Guide_Biomass_Gasification_EN.pdf

From: Stoves [mailto:stoves-bounces at lists.bioenergylists.org] On Behalf Of CHRISTA ROTH
Sent: February 16, 2018 8:22 AM
To: Discussion of biomass cooking stoves
Subject: Re: [Stoves] Off Grid Pellitizing issues --- was Re: Bulk density of LPG vs pellets

Interesting contribution, thanks Dr. Karve, 

What type and size are the briquettes? I assume they work as boiler fuel but not really in household size stoves? 

which again leaves the question how best  biomass /ag-waste can be transformed in the field or closer to the users into medium-high-density fuels with a predictable performance. 

what type (screw extruder? power requirement) and make/brand are the corresponding briquetting machines you are talking about?

My limited own experience with screw presses is that you need to maintain the screw nearly every day, if you want a continued performance of the briquetting machine. 

Steven, 

do you know of any of the systems you propose that are a bit fuel flexible when it comes to moisture content and particle size of the biomass input? 

and that can be run without an engineer on standby?

what I have seen in African contexts so far, especially on the gasifier / internal combustion engine set-up, is a graveyard of clogged-up engines, due to lack of gas scrubbing and/or inconsistent feedstock. They do work theoretically but I haven’t seen them in prolonged practice in countries where local languages don’t have a term for ‚preventive maintenance‘ .

would love to hear of some success stories of any kind of ongoing continued operation. 

those are the challenges I see before they can become win-win-scenarios.

Christa

Am 16.02.2018 um 01:46 schrieb Anand Karve <adkarve at gmail.com <mailto:adkarve at gmail.com> >:

Some 150 factories in the state of Maharashtra in India are busy converting agricultural waste into fuel briquettes. The briquettes are used as industrial boiler fuel to replace imported heating oil. They are also much cheaper than fuel oil. Fuel oil costs about $1 per litre. Just 3kg briquettes, costing $0.3 give the same calorific value. The farmers get $34 per ton of agri-waste. They are happy to get additional income.Yours A.D.Karve

On 16-Feb-2018 1:10 AM, "Law, Steven (MOECC)" <Steven.Law at ontario.ca <mailto:Steven.Law at ontario.ca> > wrote:

You can use the local biomass to make the power on a small scale!
Even better these devices are set up to have CHP and not just power only.
You could do a wood heating boiler - organic rankine cycle set up, or alternately a wood gasifier - internal combustion engine set up.
The heat can be used to dry the biomass to a low moisture content to facilitate pelletizing.
It's a win-win!

-----Original Message-----
From: Stoves [mailto:stoves-bounces at lists.bioenergylists.org <mailto:stoves-bounces at lists.bioenergylists.org> ] On Behalf Of Paul Anderson
Sent: February 15, 2018 9:24 AM
To: Discussion of biomass cooking stoves
Subject: [Stoves] Off Grid Pellitizing issues --- was Re: Bulk density of LPG vs pellets

Christa and all,

You raise an excellent question.   I changed the Subject line so the we see this discussion for what it actually is:  Offgrid pelletizing for fuel.    (There are off-grid pelletizing operations for animal-feed pellets; related but some significant differences.)

I will try to bring forward some info to answer your question about who is working on this issue, but it is not my decision to release the info or not.

There are also some very related questions:

1.  Pellet production output (size) of the units.   You gave an example of 1 ton output per hour.   Thai is not as small as it sounds (even though the big industial sites are soooooo much larger).    Assuming (this can be discussed) a household would consume 2 kg per day of pellet fuel, one ton would serve 500 households.   In a 10 hour production day, that would be supplying pellets to 5000 households (maybe 30,000 people) and need 10 tons of appropriately processed / reasonably dry biomass per day.   (If 1.5 or 2.5 or 3 kg pellet consumption per household, that would greatly change the numbers).
Variables include the operational hours per day, and if working 5 or 6 (or 7) days.    24 working days/month would mean serving 4000 households and needing 240 tons of appropriate feedstock per month.   I would suggest that maybe half or one quarter that hourly output might be more appropriate.

2.  Alternatives for generating the needed power if grid was not present.  We
> are talking at least 80 kW electrical power requirement or a corresponding PTO + diesel tractor.

3.  And certainly more aspects.

Let's see if there are some discussions and some factual inputs about this topic on this Listserv.

Paul

Doc  /  Dr TLUD  /  Prof. Paul S. Anderson, PhD
Email:  psanders at ilstu.edu <mailto:psanders at ilstu.edu> 
Skype:   paultlud    Phone: +1-309-452-7072
Website:  www.drtlud.com <http://www.drtlud.com/> 

On 2/15/2018 5:08 AM, CHRISTA ROTH wrote:
> Neil,
> the answer very much depends on the access to electricity in the area of potential production: if you want to achieve a considerable / commercially viable output of pellets e.g. 1 ton/hour, you are talking at least 80 kW electrical power requirement or a corresponding PTO + diesel tractor.
>
> Does anybody have any off-grid pelletising success stories anywhere on this planet? Would be interested to know.
>
> Christa
>
>> Am 14.02.2018 um 22:25 schrieb neiltm at uwclub.net <mailto:neiltm at uwclub.net> :
>>
>> On 13 Feb 2018 at 9:15, Paul Anderson wrote:
>>
>>> The people have
>>> access to locally sources woody biomass fuel, but are interested in
>>> having some better stoves with processed fuels.
>> Could they not make their own pellets and circumvent the problem as
>> you pose it altogether?
>>
>> Neil Taylor
>>
>> _______________________________________________
>> Stoves mailing list
>>
>> to Send a Message to the list, use the email address
>> stoves at lists.bioenergylists.org <mailto:stoves at lists.bioenergylists.org> 
>>
>> to UNSUBSCRIBE or Change your List Settings use the web page
>> http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioener
>> gylists.org <http://gylists.org/> 
>>
>> for more Biomass Cooking Stoves,  News and Information see our web site:
>> http://stoves.bioenergylists.org/
>
> _______________________________________________
> Stoves mailing list
>
> to Send a Message to the list, use the email address
> stoves at lists.bioenergylists.org <mailto:stoves at lists.bioenergylists.org> 
>
> to UNSUBSCRIBE or Change your List Settings use the web page
> http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenerg
> ylists.org <http://ylists.org/> 
>
> for more Biomass Cooking Stoves,  News and Information see our web site:
> http://stoves.bioenergylists.org/
>

_______________________________________________
Stoves mailing list

to Send a Message to the list, use the email address stoves at lists.bioenergylists.org <mailto:stoves at lists.bioenergylists.org> 

to UNSUBSCRIBE or Change your List Settings use the web page http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org

for more Biomass Cooking Stoves,  News and Information see our web site:
http://stoves.bioenergylists.org/

_______________________________________________
Stoves mailing list

to Send a Message to the list, use the email address
stoves at lists.bioenergylists.org <mailto:stoves at lists.bioenergylists.org> 

to UNSUBSCRIBE or Change your List Settings use the web page
http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org

for more Biomass Cooking Stoves,  News and Information see our web site:
http://stoves.bioenergylists.org/

_______________________________________________
Stoves mailing list

to Send a Message to the list, use the email address
stoves at lists.bioenergylists.org <mailto:stoves at lists.bioenergylists.org> 

to UNSUBSCRIBE or Change your List Settings use the web page
http://lists.bioenergylists.org/mailman/listinfo/stoves_lists.bioenergylists.org

for more Biomass Cooking Stoves,  News and Information see our web site:
http://stoves.bioenergylists.org/

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.bioenergylists.org/pipermail/stoves_lists.bioenergylists.org/attachments/20180216/88d3ae11/attachment.html>