Hybrid Car – More Fun with Less Gas

Re: GFX vs home brew - Page 6

register ::  Login Password  :: Lost Password?
Posted by Robert Gammon on April 15, 2006, 11:11 pm
Solar Flare wrote:

GREAT scoring system.

Particularly since GFX is non clogging and works with ALL sewer waters
(grey and black).

Efficiency is NOT the only criteria here. If we recover 40% to 60% of
the waste heat, we have made MAJOR strides in overall DHW production
efficiency.  Convenience, non-clogging, wife friendly are all MAJOR

Price is NOT the only factor either, but price and efficiency are Nick's
main concerns.

Nick's will have to be connected ONLY to non-toilet drains.  Nick's will
have to be periodically cleaned of matter that goes down kitchen sinks
and out the clothes washer drain.

None of these are concerns with GFX.

If we can afford one of these, either of these, these other factors,
besides price and efficiency may well be MORE of a concern to the rest
of us.

Posted by Solar Flare on April 15, 2006, 11:20 pm
Well the efficiency of heat exchange factor is not the only
efficiency. A purchased and installed product at 5% efficiency is much
more economical than a well designed, thought out, project that will
be implemented sometime after getting a 'Round Tuit

 Efficiency of installation ease.
 Efficiency of installation time.
 Efficiency of product parts and pieces aquisition
 Efficiency of marriage after the home space displacement.
 Efficiency of trial and error costs.
 Efficiency of maintenance.
 Efficiency of computer time arguing about imaginary issues.
 Efficiency of home resale after the newfangled frankenstein
paraphenalia is seen.

Posted by nicksanspam on April 16, 2006, 10:08 am

Le mieux est l'ennemi du bien. I'm better at thinking up things
than getting round tuits.

I can relate to that, having spent about 40 hours in the last 2 weeks
visiting various plumbing supply stores. It's been fun learning names
of fittings, like "bullnose T" and "Dismukes crampon lifter."

Spouses care a lot more about what's on the lawn
or in the living room than what's in the basement.

It might be nice to build more than one, with careful directions at

And only empty the crud once a year, using a hose instead of a toothbrush.

Some issues are more important than others, eg daestrom's.

This leads me to make things easy to remove.

Nah. Efficiency should be 8 vs 7, a lower price should give me more
vs fewer points, convenience is TBD, and wives may like saving more
money, or having more to spend in other directions.

20 UPIPEx.5'U-value of 10' section of pipe (Btu/h-F)
30 CFRESH=1.25*8.33'thermal capacitance of 10' of fresh water (Btu/F)
40 VGREY*3.14159*(2/12)^2'volume of 10' of greywater (ft^3)
50 CGREY=VGREY*62.33-CFRESH'thermal capacitance of 10' of greywater (Btu/F)
60 FOR SHOWER = 1 TO 1000'simulate showers
70 FOR M=0 TO 359'simulate 10 min shower + 350 min rest
80 IF M>9 GOTO 200'rest vs shower
90 IF SHOWER <1000 GOTO 120
100 RHEAT=RHEAT+1.25*8.33*(100-TF(0))'reheat energy
105 GLOSS=GLOSS+1.25*8.33*(TG(9)-55)'greywater heat loss
110 PRINT 300+M;"'";M,TF(0),RHEAT,TG(9),GLOSS
120 TF(0)=TF(1)'move fresh water up
130 TG(0)=(100*CFRESH+TG(0)*(CGREY-CFRESH))/CGREY'move greywater in at the top
140 FOR S=1 TO 8'pipe section (9<->fresh water in and greywater out)
150 TF(S)=TF(S+1)'move fresh water up
160 TG(S)=(TG(S-1)*CFRESH+TG(S)*(CGREY-CFRESH))/CGREY'move greywater down
170 NEXT S
180 TF(9)U'move cold water in at the bottom
190 TG(9)=(TG(8)*CFRESH+TG(9)*(CGREY-CFRESH))/CGREY'move greywater down
200 FOR S=0 TO 9'rest
210 HEATFLOW=(TG(S)-TF(S))*UPIPE/60'heatflow into fresh water (Btu)
220 TF(S)=TF(S)+HEATFLOW/CFRESH'new fresh temp (F)
230 TG(S)=TG(S)-HEATFLOW/CGREY'new grey temp (F)
240 NEXT S
250 NEXT M
280 SHOWERGY=1.25*10*8.33*(100-55)

0       94.56091      56.6345       71.68895      173.7736
1       92.93514      130.1973      72.0242       351.0381
2       91.38136      219.9389      72.44145      532.6472
3       89.96538      324.4244      72.83433      718.3472
4       88.72086      441.8685      73.20448      907.9012
5       87.6472       570.492       73.55341      1101.089
6       86.72784      708.6885      73.88255      1297.703
7       85.94302      855.0568      74.19321      1497.553
8       85.27464      1008.385      74.4866       1700.457
9       84.70704      1167.623      74.76389      1906.248

1167.623      4685.625      .7508075

This is confusing. The greywater output seems to warm during the course of
a shower, but I wouldn't expect that in a real system with 100' of 4" pipe.


Posted by Robert Gammon on April 16, 2006, 1:47 pm
 nicksanspam@ece.villanova.edu wrote:

Your spouse maybe, lots of others may diagree.

GFX need NO cleaning EVER, even when hooked to WHOLE house SEWER.

If you wanted to clean a GFX, its simple to remove and HOSE it down
also, but there is no need to do so.

Yours WILL need interior cleaning

This stands to reason that greywater output will rise in temp inyour
heat exchanger as the time required to recapture the heat exceeds the
amount of time that the greywater remains in the heat exchanger.  Need
higher surface area (i.e. longer, or larger diameter tubes).

Posted by Morris Dovey on April 16, 2006, 3:07 pm
 nicksanspam@ece.villanova.edu (in e1t523$v6@acadia.ece.villanova.edu)

<much snippage throughout>

|| Efficiency of installation ease.
|| Efficiency of installation time.
|| Efficiency of product parts and pieces aquisition
| I can relate to that, having spent about 40 hours in the last 2
| weeks visiting various plumbing supply stores. It's been fun
| learning names
| of fittings, like "bullnose T" and "Dismukes crampon lifter."

This may be some of the best and most encouraging news I've seen
posted to alt.solar.thermal!

I've admired Nick's tenacity in dealing with the math of solar issues;
but deplored his seeming inability to "get his wheels on the ground."

Nick, bless you! Get out even more. Take some of those fittings home
with you and play with 'em! Build at least rough prototypes of your
ideas and take pictures to share...

Morris Dovey
DeSoto Solar
DeSoto, Iowa USA

This Thread
Bookmark this thread:
  • Subject
  • Author
  • Date
---> Re: GFX vs home brew AstickfortheMUL...04-14-2006
please rate this thread