Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

  • Congratulations waross on being selected by the Tek-Tips community for having the most helpful posts in the forums last week. Way to Go!

Information on Biogas for Electricity 3

Status
Not open for further replies.

seamoose

Mechanical
Dec 3, 2007
5
0
0
US
I'm looking for information on the processing of the methane and equipment used in landfill to electricity plants . The engines used at the plant are Jenbachers . I've found tons of GE sales info but no mechanical information like start up or dicussions from the engineers that keep them running . I am considering employment in this field and am trying to learn as much about the process as possible before diving in . I am a Red Seal steam engineer with steam turbine / generation experience and had a background in heavy equipment repair .The present status of our economy and the Gov pushing money into green energy tells me it s time to learn new ! Any book titles that you may have read and think are worthwhile , or websites where I can get specific info Also any trainning semenars that are run on the US east coast Thank You Seamoose
 
Replies continue below

Recommended for you

The only large installation I have visited was using Caterpillar gas engines and the only biogas treatment they had in-line apparently was a wood chip cannister with a condensate drain.

This was a municipal sewerage treatment plant installed in the 1960's it appeared. The digester was operating on sludge and the supernatant was treated aerobically. The engines were not generating electricity, instead they were powering blowers to aerate some stages of the aerobic treatment process.

I believe it is not normally economically feasable to upgrade the biogas(much)just to burn it on site. Of course it may depend on the source of the gas and "normal" levels of contaminants encountered. The amount of Hydrogen Sulfide is usually a primary concern.
 
Thank you ,
Anything helps !
I had watched that startup the other day . I'm looking for something like a start up proceedure , trouble shooting forum , discussion about common failures involving these operations . I don't want to take this job to find its more than I can chew . I'm presently playing boiler operator /mechanic and have been seeing companies cutting the amount of operators on staff . I might have an interview next month for this job and want to know something about what I'm talking about before hand . I have 3 months left on my current contract and I will join the unemployed which is not good .
Anyone else interested I found a artical from power engineering that has more than the general info I've been finding on the web . Written by Steve Blankinship title Energy Sources hide in plain sight . I'm not on my home Cp so I don't have the site address . Anyone out here work for jenbacher ?? I'd take a few days off to go to a operation class if any are available on the east coast for a reasonable price .The web list classes in Austria which would be great but I can't get there from here ! At least not with my present wallet !
 
Your steam experience won't help much. The prime mover in a biogas plant will be either a reciprocating engine (diesel adapted for methane) or a gas turbine.

Goodling will find a lot of stuff about biogas on the Web, but I haven't seen any forums particularly for it. Have you tried the Eng-tips civil/environmental and mechanical forums?
 
I disagree with jghrist. There is a steam cycle in combined cycle gas turbine (CCGT) power plants. A lot of biogas plants run CCGT with gas turbines as the first prime movers, exhaust to heat recovery steam generators (HRSGs), and steam turbines as the second prime movers. I've seen designs for CCGT plants for wastewater treatment plant gas and landfill gas.

xnuke
"Live and act within the limit of your knowledge and keep expanding it to the limit of your life." Ayn Rand, Atlas Shrugged.
Please see FAQ731-376 for tips on how to make the best use of Eng-Tips.
 
Check out COSPP magazine, they have had some good articles.
There are LOTS of methane burning co-gen plants out there: almost every municipal land fill can support a 'trash burner.' Many large feedlots digest the cow's "output" into methane--and some of these can be 1Mw or more!

Most of these do use recip engines instead of turbines because the recip engines handle the #1 problem at these sites, fluctuations in gas quality, much better than turbines.

Also, you might check out the larger recip genset mfrs: CAT, Cummins, Kohler. Jenbacher makes big engines, too big except for the largest methane sites. GE is burning palm oil in some of their diesel sets. I know that CAT has hundreds of these 'trash burners' methane gas sets in use in the US alone.

Steve

 
I did bio-fuel engine/generators for over 20 years, mostly landfill and digester plants, 95% CAT product, some Cummins, Waukesha, and Jenbacher on the service side.

Fuel treatment can be anything from simple condensate dropout to refrigerated chillers and glycol drop out towers (mainly for H2S removal).

Primary areas of engine problems,

Ignition systems, rapid wearout of spark plugs due to high voltage demand, low service life of transformers, extenders, and spark leads, all related to running ignition at maxiumum levels trying to burn low BTU fuels. Electronic ignitions helped, and provided diagnostics to determine problem areas before complete failure.

Fuel system, usually problems associated with liquids and "gunk" (sorry, not a very technical term, but that's what it is) causing buildup and blockage, and subsequent poor performance. Gummed up fuel valves, lines and passages in heads. In prechamber type engines caused lots of check valve failures.

Valves and seats, mostly due to excessive deposits, causing uneven wear, guttering and resulting valve head drops.

Detonation problems due to excessive cylinder deposits. This one causes lots of people greif, low BTU fuels have high methane numbers, shouldn't normally see detonation issues, but increased compression due to deposits and surface glow causes preignition and knock. Most larger engines fitted with knock detection, hard to figure out sometimes what is "real" and "false" detonation.

Things get more complicated if you're also trying to maintain emissions compliance.

The fuel varies quite a bit, have watched digester systems vary 150 BTU from late at night to mid day due to sun hitting digester. Landfills can have issues with leaks, damage to gas gathering systems, and migration of "nasties" from old things dumped from the old days. You should see what a bunch of refrigerant in the gas does to an engine.

It's kind of an ongoing science experiment at most plants, you can get the engines humming along, and then they start jumping and swinging. I never found it boring, and there is lot's of inovation in areas like fuel treatment and emissions controls if the plant isn't on a razor margin.

I liked the work, but make sure you take care of yourself if you decide to go into it. Keep your shots up, and practise good hygiene, because the gas can have lots of nasty stuff in it.

I don't know of any forums or user groups other than word of mouth between plant operators and vendors. Some CAT dealers are very involved, like Michigan CAT and Patton Power Systems. Jenbacher has limited support, some DDA dealers worked on them. A few other players in the game for awhile was Deutz, thru Stewart and Stevenson, and some auto derivatives using Ford and GM industrial engines.

Waste Management ran a number of sites for several years, also a company called Minnesota Methane, and Fortistar.

It's not a bad way to get rid of gas that would normally go to waste, but because the fuel is "free' doesn't mean it's an especially cheap way to make energy. We used to figure that biofuel engine maintenance costs were about 150 to 300% of a comperable sized engine running on pipeline fuel, depending on fuel quality and emissions requirements.

Hope that helps, good luck.
 
Thanks
Very helpful info catserveng.Thanks This Co. uses Five large jenbachers .( Why I'm looking for a jenbacher class) And i did see a chiller out in the yard connected to the scrubing system . They require at least a blue seal steam ,company requirement not the state .The state hasn't any license requirement for this type of operator . (YET!) This company runs steam and cw plants also . Anyway they called me !! . They asked me to take a look at the operation and see if i was interested ! To tell you the truth I find it quite intrigueing , new technology and big engines to play with instead of my HD twins !!I was a heavy equipment mech in my younger days so the engines would be play .Had 6 or 7 electrical and electronic courses over the last 6 years pluss some time in a electrical shop so I can handle some ele troubleshooting . I presently handle control and fire sys work at my present job . Only I wish I was 10 years younger !
thank You Seamoose
 
I don't know of any US Jenbacher training. I've done some work on many of their units, and did some subcontract commissioning for them after someone I had worked with at CAT went over to them.

For many years they were the people to beat, their engines always had great efficiency and emissions capabilites, and their control systems performed better than just about everyone else's (including CAT's). Parts was a bit of a challenge at times. There is really nothing magical about their engines, their service manuals can be a challenge at times, but I have found their factory support quite good, except for language issues at times (found emails actually worked best). The newer engines have very complex control systems, but for the most part, once past commissioning I haven't seen many problems with them. If you have been around turbines you'll tend to find them less intimidating than technicians from an IC engine background.

Most of the biofuel plants I know are on long term contracts, so they offer pretty stable employment if you can handle the long hours and lots of interrupted "off time". I haved stay in touch with quite a few operators, all are still working, and the ones who are willing to stay on top of things are staying well employed. But these usually are not easy jobs, and you'll find biofuel engnes and their support equipment take a lot of TLC.

Sounds like the plant your looking at has some cogen as well, with the steam and CW systems, so it looks like there would be plenty to keep you busy.

Good luck!
 
We are in the process of commissioning 2 x 1MVA Jenbachers (containerised, fully automatic, remote operation) on land fill gas The technology has come a long way in the last few years on these type of machines in terms of wear due to landfill gas. Scrubbing system is blowers and chillers, quite basic, with a bypass flare. In our city Jenbacher also supplies sets for operation on sewage gas from digestors.. makes lots of money for the utility, but high maintenance costs
 
Over here in UK there is a mass of technical stuff, since the landfill industry is regulated and mature..

search for "Landfill Technical Guidance Notes" find LFGTN08, it is about engine emissions.

More on biogas than landfill, but useful

look in publications for "DSEAR Industry Codes of Practice".

I know that the regulatory system and standards are different in the usa, so please use these with caution.

Finally, see and look for "layout of power plants". There is some detail about biogas engines

Hope this all helps
 
awesome forum! Lot's of helpful information.

catserveng: I've been employed as a jack-of-all-trades (optr, mech, tech, IT, electrician) for 2 years in the landfill-gas-to-energy industry (working on CAT3616's, both ESS and ADEMIII setup), prior USAF 3E0X2 power production. Your summary of the technology and the challenges facing it could not be any truer. I have a few questions for you, kind sir.

seamoose: It's an awesome and unique field to be in. All of what catserveng said is accurate to the teeth. Engine backfires are the best (if it's night time the stacks look like big ol' cannons on steroids). Do you know what kind of emission standards they have?
 
Hi
, Thank s . I just got word from my BA that the company transfered someone inside to the site .After 2 interviews and 2 trips to the plant on my own time ! I've found it to be interesting but maybe they felt i was a little over the hill for it . oh well . maybe he'll find me a nice boiler job to cuddle up to ! thanks guys Seamoose
 
Seamoose,

Sorry to hear you didn't get the job. Maybe a blessing in disguise, I was at two sites this week, both with CAT G3616's and the operators looked pretty wore out.

Chaosghost, be happy to answer any questions I can, you may want to start a new thread.
And I agree, this is the best forum for technical info I have found, thanks to ALL who contribute, both the questions and the answers.
 
Status
Not open for further replies.
Back
Top