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Chlorine Injectors

related country: Ethiopia

Hi all,

Does anyone have any experience with in-line chlorinators such as the below product? If so, do you have any lessons learnt/ other recommendations for similar products? We are looking at using them for a project in Ethiopia for dosing gravity-fed water systems. I would also be interested in any recommendations for dosing water directly from a handpump.

Thanks! Martin


Hello Martin, I have no experience of these chlorinators in particular but just a general comment on chlorination systems. The chemicals used (sodium or calcium hypochlorite) are hazardous and must be handled with care. I am sure the suppliers of the equipment will give you all the necessary health and safety information but you can check it out here Regards John

John Throup gravatar imageJohn Throup ( 2019-08-23 07:50:44 )

7 Answers

Steve Oxtoby

I have used these for chlorination of water in Haiti that was reasonably successful although did have some issues with spares and one specialist part that was needed that had been discarded in error.

Reasonably successful but points to watch out for are that there is a minimum pressure required for operation and that may be an issue in your gravity fed system. Also the operation at a trickle flow is not good and so you would need to ensure that there was a certain flow or no flow to get better results.

The other thing is that the sustained operation will depend on having a supply of spares and a reasonably skilled person to maintain the system.

Similar to all hypochlorite injection systems there will be scaling issues in hard water areas which will increase the maintenance requirement.

The dosing is reasonably flow proportional but there is no control of the actual residual and so the residual achieved will vary depending on the solution strength and this may vary as batches are made up and because of thermal decay of hypochlorite.

Brian Skinner

Hi Martin,

You may like to look at the WELL publication 'Chlorinating small water supplies; a review of gravity-powered and water-powered chlorinators' from

Best wishes,



Hi Brian, thanks for the link. It only appears to be the abstract on that page though. Do you have a link for where I can download the study? Regards, Martin

martin.findlay gravatar imagemartin.findlay ( 2019-08-29 13:05:30 )

Brian Reed gravatar imageBrian Reed ( 2019-09-11 14:14:41 )

Sorry Martin for not noticing your message of 29/8 until now. I've had some messages spammed out. Thank you Brian for posting the link which should work.

Brian Skinner gravatar imageBrian Skinner ( 2019-09-16 07:20:01 )

No problem, thank you for the link!

martin.findlay gravatar imagemartin.findlay ( 2019-09-18 08:58:57 )

Hi Steve,

Thank you for your response. It's useful to get some lessons learnt. Spare parts chains and complexity of O&M are my biggest concerns with this product.

I've since found out that the makers of Aquatabs have now developed two products to install onto the inlet to a tank or in-line, called the Aqua Flo and and Aqua Inline which are much cheaper than the Dosatron or similar devices, but still seem to provide a constant FRC in the water at the point of collection. I don't suppose you have any experience in these as well?

Regards, Martin


Hi Martin, there has been a recent evaluation of the AquaFlor/Aqua Inline, the results are published here: Looks like the product in that specific context was effective in reducing diarrhoea incidences (by 25%) and in reducing expenses on medical treatment.

Matthias gravatar imageMatthias ( 2019-09-30 13:55:03 )

Hey Martin,

we have some dosatron system here in Bangladesh, they are pretty expensive and the spare part issue was already mentionned. The main problem we found is sand, coming through the sieve into the pump and blocking it. Here a frequently maintenance and cleaning might be needed.

Furthermore we are using TEKNA dosing pumps. That comes with a solar panel, charge controler and battery. To trigger the pump you would need a flow meter with a triger cable that triggers chlorine solution injection every e.g. 100l.

Best regards, Andreas*


Great thanks for the feedback! It's good to have some practical feedback on O&M.

martin.findlay gravatar imagemartin.findlay ( 2019-08-29 12:56:15 )

You do need to think about sustainability as well as technical effectiveness.

Is an interesting paper that’s worth reading.

Don’t forget about the whole treatment chain - safe storage is essential if the chlorine is going to make much of a difference.

frank lawson

Hi Martin, I've recently been made aware of an automatic chlorinator for community water supplies called ZIMBA, that is manufactured in India, It has been used in some WaterAid projects in India, but I don't have any feedback on its performance. The manufacturer states that it works without electricity, has no moving parts, weighs around 11 kg and can be easily transported, and installed to a community water source in 30 minutes requiring no special tools, it is capable of chlorinating water at the rate of 15 litres per minute and being community scaled, is more cost effective than domestic water disinfecting systems. These units have been installed, and are operational, in several countries including India, Bangladesh, Kenya and Dominican Republic - in projects run by various NGOs and research organisations including UNICEF, WaterAid, EAWAG, Switzerland, ICDDR, Bangladesh and The Hope Foundation. It has also been used in disaster situations like the Nepal earthquake and Rohingya Refugee crisis. The unit costs around 300 US dollars excluding shipping. Have a look at their website and see what you think. Frank Lawson


Hi Frank, thank you for your response. I'll look into the ZIMBA, it looks great on paper! Are there any M&E studies of their operation available? I also noticed that the makers of Aquatabs have created a similar device, called the Aquatab Flo. Do you have any experience with these? Regards, Martin

martin.findlay gravatar imagemartin.findlay ( 2019-09-18 08:59:25 )

Hi Martin, I'm afriad that I haven't seen any operational reports about the ZIMBA unit, but I agree that it looks good on paper. The Aquatab Flo looks a similar concept and again looks good on paper, however it's new to me. Regards, Frank

frank lawson gravatar imagefrank lawson ( 2019-09-24 15:44:01 )