CHEMICAL DISPENSING TAPS

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We are working with a rural community who draw water from springs and wells and take it home foruse in 20 litre containers .

We have in mind installing a sodium hypochlorite dispenser which can dispense only 10mls of the Hypo solution  to give 40ppm of disinfection  enough to disinfect the water in the 20 litre containers i.e 2ppm per litre.

Can anyone out there advise on how we get such dispenser taps which can dispense exactly 10mls when pressed.

Best Regards

P.W.Karani

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7 Answers

  1. Dear Karani,

    Please avoid using chemicals. We have alternative solutions that have worked well for communities in Kenya. Talk to us. Check us out at japmorfilters.co.ke

    1 Comment

  2. Hello P W Karani,

    It is best to remove turbidity before chlorinating. We have developed a self washing filtration system for use in off-grid locations to enable this - see case study attached. The chlorine is applied more centrally using a Klorman sanitiser with chlorine cartridges.

    Kindly Nigel Heeler    www.waterreach.co.uk

    1 Comment

  3. Hi Peter, please check your calculations for dosing sodium hypochlorite.  If you have a 3.5% solution (normal household bleach) this equates to 0.35 g in 10ml.  when this is added to 20 litres it gives a concentration of 17.5 mg/l, which is quite high and people are likely to avoid dosing as it will give a strong chlorine taste.  We had usually recommended adding 1 teaspoon to 25 litres which gives a concentration of about 7 mg/l, still quite high but allows for some degradation and random measurements.

  4. Hi Mr Karani - the underground collection of water is a good idea - filtered by a simple micro filter, placed in line, and easy to access. Dosing is dangerous and inconsistent and chemical input is always abused, and naturally on-going which requires management. The collected water must be fed to a holding tank placed nearby and the inlet to the tank must have a Merus Ring on it. The Merus Ring will reduce the effective contamination of most if not all elements contained in the water and continue to do so in the tank before it is used or consumed by anyone. It is the simplest and easiest method to manage  in rural areas. There is no maintenance cost or supervision required and it requires no power source to run. It works 24/7 and covers all pathogens, bacteria, lime scale and metals, trace elements and micro bacteria infestation. It reverses oxidation and dissolves rust and therefore can halt corrosion. It is guaranteed for 5 years by the manufacturer from date of installation.

    Kindly let me know if you need any further information. Best regards,

    Bryan Roberts - Merus South Africa.  

    1 Comment

  5. Although it is better to treat the water than risk disease, chemically treating water usually involves dangerous compounds like sodium hypochlorite and is not ideal, especially when the people using it are not trained professionals.  There exists a substantial risk of poisoning particularly where children are concerned.  Where a spring exits the ground before it has a chance to mingle with animal droppings etc.  the water should be relatively free of harmful bacteria.  The best case scenario would be to build a cistern and capture the water before it reaches the surface where contamination occurs.  There are several good methods for doing this. I’m happy to help if I can.  If the water is captured in a cistern and yet remains contaminated you could then install filtration or even chemical treatment that would accurately maintain potable drinking water.  If none of this will work and treatment has to be done by the two liter bottle then I suggest using a personal micro filter water purifier.  They are becoming better, higher volume and more affordable all the time.  I hope this helps, pleas feel free to contact me if you think I can help in someway. 

  7. Dear Karani,

    I did not use such small system. Please check following file:https://www.aliexpress.com/item/1005001270792428.html

    BR

    3 Comments

    3. Careful even after getting right dispenser the key issue is not disinfection alone but contact time and residual before consumption

       

      1 Comment reply

      1. Thank you Barasa

        The contact time will be between when the water drawing people fill their buckets , dose with chlorine  and transport the water barrels home.

        This is assumed to be adequate time for contact. 

        The initial dosage will be 2ppm so as to wear away to around 0.4 mg/l in 30 mins