A New Technique to Purify River Water for Use in Rural Communities

  • varkey
  • varkey's Avatar
    Topic Author
  • Posts: 14
  • Likes received: 2

Re: A New Technique to Purify River Water for Use in Rural Communities

Thank you.
0.25 g of seed powder can be measued with a senstive balance. For practical purpose it is approximately 2 pinches.
Using slightly more than this amount is not very critical. The excess powder that does not take part in the clearing process
will remain in the filtered water. It will not affect the water quality, except a slight increase in turbidity. Use of very tightly woven cloth
(e.g.muslin, if available) can further reduce turbidity. Filter paper is found to reduce turbidity by about 35% compared to cloth.
All the best.
You need to login to reply
  • varkey
  • varkey's Avatar
    Topic Author
  • Posts: 14
  • Likes received: 2

Re: A New Technique to Purify River Water for Use in Rural Communities

Thank you. The article is quite interesting. It is an example of the use of Indigenous Technology (IK). More work is needed
for grey water reuse / treatment.
You need to login to reply
  • F H Mughal
  • F H Mughal's Avatar
  • Senior Water and Sanitation Engineer
  • Posts: 1032
  • Karma: 20
  • Likes received: 221

Re: A New Technique to Purify River Water for Use in Rural Communities

Dear Dr Varkey,

In Table 1, some parameters have increased after 4 hours of operation.

Sulfate has increased from 1 to 4 mg/L; chloride from 4 to 6; potassium from 1 to 5.4; sodium 18.64 to 26.87; and more importantly, copper itself has increased from 0 to 0.24 mg/L. Can you please clarify?

Attached is a WHO publication on copper in drinking water.

Regards,
F H Mughal
This attachment is hidden for guests.
Please log in or register to see it.

F H Mughal (Mr.)
Karachi, Pakistan

This message has an attachment file.
Please log in or register to see it.

You need to login to reply
  • varkey
  • varkey's Avatar
    Topic Author
  • Posts: 14
  • Likes received: 2

Re: A New Technique to Purify River Water for Use in Rural Communities

Thank you for the comments.
This attachment is hidden for guests.
Please log in or register to see it.
This attachment is hidden for guests.
Please log in or register to see it.

My idea of a comparing those parameters in raw water and treated water was to test how far they change after treatment and to find out if the treated water has any of the parameters outside the accepted guidelines for drinking water quality. This was to test the efficacy of the technique to see if it could be recommended for use.(needs more tests for confirmation). After comparing the two, there is increase in some elements after treatment. It is not surprising because moringa seeds contain these elements and after mixing with raw water they can leach into it and can be carried over to treated water during decanting. Increase in copper is not from copper wire or pot used in disinfection. Please see attached file for a list of nutrients in moringas seeds. (This is from literature; I did not do a nutrient analysis of the seeds. They might differ in samples grown in different countries). However they are all within accepted limits for drinking water and therefore I don’t think it should be a concern. Moreover as seen attached file, the daily intake limits of these elements seems to be much higher than what one would get by consuming the treated water.
Trace elements (including copper) are needed in small quantities for proper body function which is obtained from foods. If they are available in the treated water, will it not supplement them by consumption? Just a thought; I am not an authority to say so! A nutritional analysis of the water might be useful.

This message has attachments files.
Please log in or register to see it.

The following user(s) like this post: F H Mughal
You need to login to reply
  • F H Mughal
  • F H Mughal's Avatar
  • Senior Water and Sanitation Engineer
  • Posts: 1032
  • Karma: 20
  • Likes received: 221

Re: A New Technique to Purify River Water for Use in Rural Communities

Thank you for your enlightened reply.

How to know when to replace the seeds. In poor household settings, labs are not available to test the water quality. They go by the thumb rule, say, for example, replace the seeds once a month at 5 liters/day flow rate, or its equivalent (roughly).

Regards,
F H Mughal

F H Mughal (Mr.)
Karachi, Pakistan
The following user(s) like this post: SamOricha
You need to login to reply
  • varkey
  • varkey's Avatar
    Topic Author
  • Posts: 14
  • Likes received: 2

Re: A New Technique to Purify River Water for Use in Rural Communities

Thank you.
Once seed powder is used up, it should be thrown away along with the residual and replaced with fresh ones because during coagulation the seed particles (more specifically the proteins, MOCP) attract dirt from raw water (an electrostatic phenomenon), get clogged and settle down. It cannot be re-sued. At the rate of 0.25 g /L, 5 L raw water needs 1.25 g powder. 1 kg powder costs about $ 1.00 or less (in most countries) which is enough for 800 L water. Very cost effective. Copper can be reused several times. Only needs occasional cleaning which can easily be done using lemon juice mixed with a small amount of salt. Everything can be done in a rural household except quality test which should be done in a laboratory, once in a while by, say, the local water authority.
Regards,
Dr. Varkey
You need to login to reply
  • F H Mughal
  • F H Mughal's Avatar
  • Senior Water and Sanitation Engineer
  • Posts: 1032
  • Karma: 20
  • Likes received: 221

Re: A New Technique to Purify River Water for Use in Rural Communities

Thank you for your response.

Turbidity in canals here is high (500-800 ntu). From Table 1, it appears, you have studies waters with 200 ntu turbidity.
What changes would you suggest for highly turbid waters (500-800 ntu)?

Regards,
F H Mughal

F H Mughal (Mr.)
Karachi, Pakistan
You need to login to reply
  • varkey
  • varkey's Avatar
    Topic Author
  • Posts: 14
  • Likes received: 2

Re: A New Technique to Purify River Water for Use in Rural Communities

Thank you.
If turbidity is high only after rain it can first be reduced by allowing water to stand for some time for natural sedimentaion to occur.
It can then be decanted and use smiliar amount of moriga powder for further clarity. If turbidity is always high, more seed powder
(say 0.3 - 0.35 g/L) may reduce it to desired levels. I think 500 - 800 NTU is not normal in river waters.
Regards,
Varkey
You need to login to reply
  • F H Mughal
  • F H Mughal's Avatar
  • Senior Water and Sanitation Engineer
  • Posts: 1032
  • Karma: 20
  • Likes received: 221

Re: A New Technique to Purify River Water for Use in Rural Communities

Phuleli Canal in Hyderabad has high turbidity. As you rightly say, it goes further high during rains. In addition, there is significant soil erosion.
High turbidity of Phuleli is recorded is recorded in papers.

Natural sedimentation will take a long time. Further, if the turbidity is colloidal in nature, it won't settle.

Would you recommend roughing filters? See this link:

www.ircwash.org/sites/default/files/Wegelin-1996-Surface.pdf

Regards,
F H Mughal

F H Mughal (Mr.)
Karachi, Pakistan
You need to login to reply
  • varkey
  • varkey's Avatar
    Topic Author
  • Posts: 14
  • Likes received: 2

Re: A New Technique to Purify River Water for Use in Rural Communities

Roughing filters are good enough for waste water management and as a pre-treatment procedure for potable water.
Regards,
Dr Varkey
You need to login to reply
  • F H Mughal
  • F H Mughal's Avatar
  • Senior Water and Sanitation Engineer
  • Posts: 1032
  • Karma: 20
  • Likes received: 221

Re: A New Technique to Purify River Water for Use in Rural Communities

Roughing filters are not used for wastewater management. The name of the publication is:

Surface Water Treatment by Roughing Filters

Regards,
F H Mughal

F H Mughal (Mr.)
Karachi, Pakistan
You need to login to reply
  • varkey
  • varkey's Avatar
    Topic Author
  • Posts: 14
  • Likes received: 2

Re: A New Technique to Purify River Water for Use in Rural Communities

Thank you for the information.
I am curious to know the problem in Phuleli. Is canal the only source of water for the community?
Regards,
Dr. varkey
You need to login to reply
Share this thread:
Recently active users. Who else has been active?
Time to create page: 1.649 seconds