New job on a Jenbacher Gas Engine

[Gunny]

Might be switching jobs. Working on these things.

Video of Starting up a Jenbacher Gasengine 16 cylinders:



http://www.youtube.com/watch?v=CXMaJ...eature=related

[Elden DuRand]

Gunny:

Now that you showed us the flick, tell us something about them.

Take care - Elden

[Ray Cardoza]

whats it for?

[Gunny]

These things run on dry fuel, methane, natural gas, coal mine gas, digester gas or process gas. A lot of that gas used to be vented into the atmosphere or burned off. Now it is collected and burned in an engine, engine turns a generator and the generator puts power on the grid. Talk about green power.

A lot of land fills, especially large ones, make enough gas for it to be economicaly feasible to collect it and use it for fuel. There are a few landfills within a 2 state area here that are doing it right now, as we speak, turn trash into electricity in an enviromentally responsible way.

They pretty much run 24 hours a day, 7 days a week. Oil sample weekly and generally get an oil change once every 2,000 hours.

One of the fuels and the process that I think is real neat is the digester gas system. A waste water plant with a digester where bacterial action breaks down the waste, sewer gas is a desired product of the digester process, it is scrubbed/treated to remove the sulphur and burned as fuel, the engine spins up a generator to make electricity, waste heat from the engine is used to heat the digester to improve the process. A number of plants make all of their own electricty and some even make enough to export.

A little more to it than just taking care of the engines. Except for coal mine and natural gas, it needs treating/scrubbing to remove harmful or undesirable "stuff" in the gas. One problem with running landfill methane gas is lady's cosmetics. When they decomposed in landfills, they generated a very undesirable product that mixed with methane and when burned in an engine causes a build up in the combustion chambers that made a mess. Burned valves, causes rings to stick, raises compression, foules turbo charger blades and clogges mufflers. Engineers have pretty much solved this problem.

A few other things involved with this process is ensuring the engines are running at peak efficiency. No need to waste what we got. Emmissions, we ensure that we are not spewing harmful emmissions out into the atmosphere.

Electrically we also parallel to the grid and export the power we make. A lot more to it than to just connectting and let it run. Got protective devices and relays to protect our equipment and the grid against problems.

The little things at the site that make it all happen safely and efficiently. Gas leak detectors, gas scrubbers and compressors, transformers, circuit breakers, control circuits, heat exchangers, emmission controls, monitoring systems and more, all part of the job.

Doing it all safely and efficiently is the name of this game.

[rrfxxxr]

Interesting. So how many JigaWatts do you get out of that thing?
(Those guys running waste gas in a V16, me running waste cooking oil in 3 cyl lawn mower. We may bankrupt OPEC after all.)
Later,
Sbw

[Gunny]

Steve:

Some V-20 we have in operation now are making 1820kW. Depends some on btu content of the fuel.

GE has a new V-24 out that will make 3mW, first one to be delivered in Holland soon.

6.9 L per cylinder. 7 1/2" bore.

[Raymond]

My grandfather pioneered the use of gas engines using digester gas in Charlotte N.C. around 1920. All of his wastewater plants had engines which produced 100% of the power required. Many plants didn't have a utility connection. The Winston Salem Elledge plant built in 1956 had three 600 KW Worthington Duel fuel engines and was not connected to the power grid until 1969. The new consultants can't even spell engine so they twist the numbers around to show that engines loose money. When they took out the engines at the Elledge plant in 1994, the power bill increased by 1 million dollars a year. That proved that the engines were making 1 million dollars a year with an operating cost of around $25,000 a year. It's hard to imagine that kind of ROI and then see it trashed by twisted math. The environmental impact is enormous. The coal or gas required to generate the power is horendous mainly because fossil fuel power plants are less than 30% efficient. I have the numbers if interested as I did a study to convince them to go back to engines. They refused to look at it because they have already proved it is a loosing proposition.

[IanR]

Something sounds fishy.
Those consultants don't own stock in the POCO do they?

[Raymond]

No. They don't even know what demand is and they just don't have the capability to work with engines and they aren't about to hire their competition to to do what would become the focal point of the job. I designed a computer control system for the Elledge plant upgrade in 1994 which which would have costed 1 million dollars with a payback of less than 2 years. It was a power shifting system that allowed them to run all day on-peak with no utility power and run utility power at night. The demand charge was $60,000 a month. I left the company before it was built and the company convinced the client not to do the job but take out the engines instead. They sold the engines (2 X 360 rpm Delaval Enterprise 2,000 KW Dual fuel, and 2 X 600 KW Delavals one of each fresh rebuilds and all the parts to rebuild the other 2) for $10,000. They couldn't build it without me and the company I went to was the original designer of the plant and they weren't about to have us in the job or even on the plant site. All the preliminary modifications to the plant in preparation were ripped out and scrapped, some equipment still in the box. There are 2 more (Waukesha 2895s) in Durham my Father put in in the mid 80's to replace the original engines installed in 1925. There are just sitting because the engineers have screwed up the cooling and gas systems so that the engines can't develop full power and overheat. Seems the cost to fix them would be more than they could save.

[Gunny]

Friday did a regularly shceduled service on an engine. Was giving a knock alarm if loaded beyond 925kW.

Pulled the valve covers and checked valve clearance, all were fine. Pulled spark plugs and bore scoped the cylinders. Fold the surce of the knock, #19 piston showed evidence of making contact with the exhaust valve, cyclinder wall scored at about 2 o'clock.

Drained the coolant, pulled off the exhaust heat shields, intake manifold and sxhaust manifold off of #19. Removed the engine side cover, pulled the head, pulled the pistone, then the cylinder liner and determined we had a broken ring. In went a new liner, piston w/rings. cleaned the head, new rod bearing and put it back together.

Had it running just over 3 hours after we decided to take it apart and investigate. Ran it at 200kW for 10 minutes, went to 500 for 20 and then ran it to 975kW. Computer showing some ignition misfires once every 2 minutes or so, we left it at 975 and will play with the ignition system Monday to see where our we might have an electrical gremlin. 20 coils, 20 coil wires, 20 spark plugs, could have taken a few hours to track that one down, will be a good job for a rainy Monday.

Wednesday they added some new gas wells to the system. Means they had lines open and air had gotten in. We shut down the engines so they wouldn't get a gulp of air and they purged the gas lines, burned off what was in them. Real nice blue flame about 6 feet across at the bottom and every bit of 60 feet tall, fringed in yellow. Cleared out the lines and put the engines back on line.

Turning out to be an interesting job.

[Bud Tierney]

Was going thru my Wauk stuff the other day; found a 1966 manual for their V12 L-7040G (7040cid) 93/8x81/2, supposedly a good sized engine in its day.
Understand they later made a V16 of some 9000+ci (9390??); sounds almost puny compared to some of these.

[Raymond]

It's all a function of engine speed. The DeLavals at the Elledge Plant were 2600 HP at 360 RPM continuous. They were 28,600 CU. in.(17X21) 6cyl. pix on the net. They were dual fuel not bi-fuel. They inhaled digester gas that was ignited by the injection of diesel fuel by a std. bosch injection system and could run any ratio of fuel from 2% DIESEL to 100%. The fuel consumption was dyno tested ar 7,200 BTU/HP-HR which I have never seen equalled. They also were low emission because of the low combustion temperature and extremely lean mixture.

[The Engineer]

keep it comming this is great thanks
about 3 ks from us is a sewerage treatment plant they run all their equiptment on the gas but they have a big waukesha driving a big genset and if the wind is in the right direction guess who is outside on a still night its the most beautiful deep thump thump thump that you could imagine