More compact DEWATS technology?

  • jankn
  • jankn's Avatar
  • Posts: 35
  • Karma: 8
  • Likes received: 21

Re: More compact DEWATS technology?

Dear Detlef

Thank you for pointing out all those interesting documents and sharing the numbers here - pretty impressive.

As it was with this particular housing complex project, the owner cared about a wastewater treatment system only at a rather late stage of planning (i.e. construction of the houses already started). I see this happening quite some times. This leaves only little flexibility in the kind of system to implement and the low energy and O&M inputs of DEWATS make them worth while without biogas. But I suppose, the numbers you have given speak for themselves.

Would you have any idea in which range the "actual" caloric values of the biogas production in a case like you mentioned earlier (4000 p.eq. with 800 mg/l COD) for a low-tech biogas plant could be?

Jan Knappe

Doctoral Researcher on environmental performance assessment and modeling of on-site wastewater treatment systems
Trinity College Dublin & University of Limerick
Email: jan.knappe(at)tcd.ie, Twitter: @JanKnappe

You need to login to reply
  • AquaVerde
  • AquaVerde's Avatar
  • Posts: 375
  • Karma: 15
  • Likes received: 69

Re: More compact DEWATS technology?

Dear Jan,

I made my self a little Excel, but I am not sure about my theoretical "Milchmädchenrechnung" (simplistic equation), as I am not THE biogas-expert with many years of hands-on field experiences ;-).
I will send you my Excel direct to your e-mail.
Maybe your biogas-colleagues Pedro, Christoph and H-P Mang could comment on it too!?

See Mr. Nils Warburg's very complex EXCEL on " Calculation of Carbon Dioxide Equivalent Emissions of DEWATS in Indonesia " and try it out with your numbers (4,000 p.e. with 800 mg/l COD) too.

CH4 in biogas has a heating value of about 35 MJ/m3. If you are lucky you can produce about 0.12 m3 CH4 / kg COD removed. Treating sewage with a concentration of 1.0 kg COD/m3 you can raise 4.2 MJ/m3 sewage treated. If you can convert this energy in heat- or electrical energy you are lucky.

in short for 0.8 kg COD/m3:
4,000 p.e. (150LPD) with COD 0.8kg/m3 = 480kg/d: (1 kWh = 3.6 MJ)
caloric values: 1,209 kWh/d = 441,504 kWh/a
if 0.07 EURO/kWh = 30,905 EURO/a

Seams to me very valuable, but still I am not "total" sure by my self.
I am interested in commends and advices by colleagues.

All the Best
Detlef

www.aqua-verde.de
Sanitation-Solutions without external energy
Low-Tech Solutions with High-Tech Effects
"Inspired by Circular Economy"
www.flickr.com/photos/aqua-verde/
You need to login to reply
  • jgoyani
  • jgoyani's Avatar
  • Jignesh Goyani
  • Posts: 3
  • Likes received: 0

Re: More compact DEWATS technology?

Yes, you can use vortex system instead of PGF and Polishing pond. Contact for vortex system at CSR auroville.
You need to login to reply
  • AquaVerde
  • AquaVerde's Avatar
  • Posts: 375
  • Karma: 15
  • Likes received: 69

Re: More compact DEWATS technology?

Kind of comprehensive information on VORTEX:

www.blueeconomy.eu/blog/the-power-of-the-vortex/

Vortexes can clean water, as their rotational speed is higher at the bottom than at the top. In this way, particles are sucked down the vortex and can leave the water by a vacuum created at the end. Furthermore, the water is set into a chaotic state. The constant swirl presses air out of the water and sucks it back in, so that microorganisms are stimulated or die.

This technology is not to be confused with expensive vortexes that dubious websites promote to customers, propagating that they would “harmonize”, “revitalize” or bring back the water to a “virgin state”. On the internet one can read the most bizarre promises about vortexes. These attempts of fraud should however not discourage people to realize the real potential the physical use of vortexes has.


www.aqua-verde.de
Sanitation-Solutions without external energy
Low-Tech Solutions with High-Tech Effects
"Inspired by Circular Economy"
www.flickr.com/photos/aqua-verde/
You need to login to reply
  • jgoyani
  • jgoyani's Avatar
  • Jignesh Goyani
  • Posts: 3
  • Likes received: 0

Re: More compact DEWATS technology?

Hi, with DEWATS instead of wetland or secondary treatment you can use vortex developed by CSR, auroville.
Vortex is very good, we have tried at our site for 1.05 MLD DEWATS.
You need to login to reply
  • Marijn Zandee
  • Marijn Zandee's Avatar
    Topic Author
  • Student and part time Biogas and WASH consultant
  • Posts: 240
  • Karma: 21
  • Likes received: 111

Re: More compact DEWATS technology?

Dear Jignesh,

Thank you for your post. Are you associated with CSR-Auroville, or with another organization?

I find the Vortex idea quite interesting, so I am trying to find more information about it. So far I have found:

www.cseindia.org/userfiles/Vortex-dewats%20Aug2013.pdf

From that publication it seems that the working principle is intense aeration of the water as a polishing step. Can you confirm that this is true? Or is there another working principle that I am missing here?

In general, does anyone have some more technical/scientific reading materials regarding these vortices?

Regards

Marijn

Marijn Zandee

Kathmandu, Nepal

E: This email address is being protected from spambots. You need JavaScript enabled to view it.
You need to login to reply
  • AquaVerde
  • AquaVerde's Avatar
  • Posts: 375
  • Karma: 15
  • Likes received: 69

Re: More compact DEWATS technology?

Dear Marjin,

Just use other names for the same "vortex": en.wikipedia.org/wiki/Hydrocyclone
"wirbel separator", de.wikipedia.org/wiki/Fliehkraftabscheider and so on. You will find all on the internet, from explanations up to suppliers.

A Swedish example of a small version of vortex for small luxurious (water flush)-sanitation (which do not need extra power) is called Aquatron: www.aquatron.se/how-it-works/separator/

This cyclone-devices can be used for separation, mixing or aeration.

Regards,
Detlef

www.aqua-verde.de
Sanitation-Solutions without external energy
Low-Tech Solutions with High-Tech Effects
"Inspired by Circular Economy"
www.flickr.com/photos/aqua-verde/
The following user(s) like this post: Marijn Zandee
You need to login to reply
  • Decentral
  • Decentral's Avatar
  • Independent consultant with special interest in decentralized wastewater systems
  • Posts: 10
  • Likes received: 1

Re: More compact DEWATS technology?

Hi,
When land for constructed wetlands or infiltration is not available may be you have to look at a compact aerobic treatment facility, which might achieve the required level of treatment. Alternatively, anaerobic followed by aerobic treatment. In this case of a hospital, may be disinfection would be necessary as a tertiary treatment, if you discharge into surface water.

Regards
You need to login to reply
Share this thread:
Recently active users. Who else has been active?
Time to create page: 1.292 seconds