forums energies: society, ecology and clean technologies

Hello,

I have a 15Kw diesel generator which I use for various things.
When it works for other purposes, I would like to produce hot water from its own heat (radiator, exhaust), excluding electricity.

Is there a possibility for example a group radiator exchanger and hot water tank?

Who has any ideas? has it already been done?

Thank you, Pierre

The exhaust mounts at what temperature?
If more than 70 ° C (very likely) a copper pipe wrapped around a serious exhaust pipe, tight, with a light insulator on top with water from a circulator at a speed fixed by the outlet temperature water should heat this water !!
3/4 of the energy is lost in heat, so there is enough to heat a house if 15KW electric, there is 3x15 = 45KW of heating !!
So the pot is to be greatly enlarged probably for a good exchanger recovering most of it !!

If less powerful group, try before on low power can identify the problems !!

See if the manufacturer has not looked at and solved this problem, see him ask to solve it, given his commercial interest in the brand image of this manufacturer !!

Since you're talking about a radiator, I assume it's a water-cooled unit?

To start, I would start from the group's cooling circuit, diverting it to a balloon with exchanger.

Caution: the circulation pump may be of insufficient power to support an additional exchanger.
Also provide safety devices to avoid overheating the engine ...

If it works but the recovered power is insufficient, we can try to recover the heat of the exhaust by a circuit:
engine -> heat exchanger on muffler -> heat exchanger in hot water tank -> radiator
But as dedeleco points out, the surface of the exhaust pipe is generally too small to serve as a heat exchanger (the proof: the gases come out hot).

you can also recover the hot air from the fan ........
but is your engine running long enough to dampen the installation?
if it rotates regularly and constantly, even if it means modifying the cooling of the latter, you might as well use the radiator as a central heating unit and replace the radiator with a volume of coolant and rotate it in radiators

if it turns from time to time, you can use it as heating (or preheating) of sanitary water on your cumulus
it's up to you to see the most suitable process

Be careful however to provide a device which allows a rapid rise in temperature of the engine, and similarly not to draw too much heat power which would prevent the engine from running at its nominal temperature.

Gaston wrote:Since you're talking about a radiator, I assume it's a water-cooled unit?

To start, I would start from the group's cooling circuit, diverting it to a balloon with exchanger.

Caution: the circulation pump may be of insufficient power to support an additional exchanger.
Also provide safety devices to avoid overheating the engine ...

If it works but the recovered power is insufficient, we can try to recover the heat of the exhaust by a circuit:
engine -> heat exchanger on muffler -> heat exchanger in hot water tank -> radiator
But as dedeleco points out, the surface of the exhaust pipe is generally too small to serve as a heat exchanger (the proof: the gases come out hot).

Yes, it is a group whose engine is water cooled (radiator).
I was thinking of using a plate heat exchanger like this. http://www.regenebatt.com/index.php?page=shop.product_details&flypage=flypage_lite_pdf.tpl&product_id=87&category_id=9&option=com_virtuemart&Itemid=30 but I am not very competent ..

dedeleco wrote:The exhaust mounts at what temperature?
If more than 70 ° C (very likely) a copper pipe wrapped around a serious exhaust pipe, tight, with a light insulator on top with water from a circulator at a speed fixed by the outlet temperature water should heat this water !!
3/4 of the energy is lost in heat, so there is enough to heat a house if 15KW electric, there is 3x15 = 45KW of heating !!
So the pot is to be greatly enlarged probably for a good exchanger recovering most of it !!

If less powerful group, try before on low power can identify the problems !!

See if the manufacturer has not looked at and solved this problem, see him ask to solve it, given his commercial interest in the brand image of this manufacturer !!

The group is quite powerful, the engine runs at 1500tm as for the temperature at the outlet (or on the pot) it is quite high I burned myself a pair of times!

zorglub wrote:you can also recover the hot air from the fan ........
but is your engine running long enough to dampen the installation?
if it rotates regularly and constantly, even if it means modifying the cooling of the latter, you might as well use the radiator as a central heating unit and replace the radiator with a volume of coolant and rotate it in radiators

if it turns from time to time, you can use it as heating (or preheating) of sanitary water on your cumulus
it's up to you to see the most suitable process

I think I'm going to take temperature measurements!
The radiator solution seems interesting here a link to the photo of my engine.
http://picasaweb.google.com/lh/photo/3r47xl-_Y6f1CO_s2Vpn4A?feat=directlink

to recover the heat from the engine block it is exactly like an oil boiler, it must be allowed to rise in temperature, then circulate the water for heat use when it is hot enough

except that for the boiler if the use of heat decreases the temperature rises and the boiler is shut down, in your case if the temperature rises it is necessary to switch on the original radiator

a large half of the power lost is lost by the water from the engine block, the other half may be lost by the exhaust, and not only the exhaust pipe, also the exhaust pipe

it would be possible to get more than 100 ° C but what good is it, unless you run a steam engine

wind copper on the original pot ... blah, surface too small, it will continue to come out as hot ... it would take a real heat exchanger with sufficient surface

I did it for much smaller group ... to recover all the heat it condenses and it's corrosive conclusion as long as it condenses, I sprinkle the interior of the recuperator with water, and I do pass this hot water through an exchanger ... with a fairly low recovery temperature it condenses the water in the exhaust and the system constantly overflows

with the passage of water through a heap of pebbles to saturate with limestone it retains NOx and other pigs from the engine

there is an interesting tip used on some marine engine: send water into the exhaust pipe: it avoids overheating, and in my case it prevents heat loss from the tube between the engine and the recuperator

I plan to manufacture this kind of water recuperator both for generator and for any boiler: wood or fuel oil: total recovery of waste heat and radical reduction of pollution

another easy solution: replace the exhaust pipe with a small oil fired boiler ... its volume serves as a silencer ... ca surface serves as heat recuperator

The plate heat exchanger is a good track. With an 3 valve and a regulator that takes into account the different temperatures (engine, water to be heated, etc ...) so that the engine always runs at the correct temperature while extracting the maximum calories.

The one you have given in links is maybe a bit small (although I have no idea how you dimmed this kind of device) but it is really cheap (I thought it was more expensive, The ties under the elbow)
To make a first try it avoids an investment too heavy.