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Sterilization of water using Chlorine Gas


Founded in 1847, the Institution’s original mission was to give “impulse to innovation” and early meetings would provide engineers with an opportunity to present their ideas to the Institution’s Members.

Captain J. Stanley Arthur O.B.E. was one such individual. Captain Arthur was an Analytical Chemist who saw service in the First World War analysing the gases used on the front. 

Captain Arthur first presented his paper: “Sterilization of water by Chlorine Gas” to the Institution on 19th November 1920. In 2020 we celebrate the 100th anniversary of the presentation of this transformative process.

Captain Arthur’s paper identified the need to purify water supplies and that because filtration alone only reduced around 98% of bacteria, it was important to find a way to remove the final 2%.

Arthur, who had a focus on the purification of drinking water in the field following WWI, identified that far more bleaching powder (chlorine) was being used than necessary. Arthur looked to the new method of sterilisation using Chlorine gas to provide a better solution and made a comparative study of different apparatus to develop a best practice approach.

Arthur identified that water purification installations which used chlorine as the sterilizing chemical along with sulphur dioxide to remove the after taste were efficient, simple and cheap to operate. Additionally a new substance, bromine bleaching powder, was introduced for warmer climates.

Arthur’s five step approach included coagulation, sedimentation, filtration, serialisation and de-chlorination. The longevity of Captain Arthur’s work can be seen today where we still follow many of these steps to purify our drinking water; filtration and sterilisation using ultraviolet, Ozone and Chlorine.

The methods adopted during the First World War resulted in there being no epidemic of any water-borne diseases.

With thanks to Sage Publishing we are able to make the paper open access here:

  • Black and white photograph of Captain Arthur's sterilization lorry
  • Line drawing of a War Office Type Motor Lorry Plant
  • Title page of "Sterilization of Water by Chlorine Gas" by Captain J. Stanley Arthur

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Credit: Captain J. Stanley Arthur, "Sterilization of water by Chlorine Gas", Proceedings of the Institution of Mechanical Engineers, 06/1920, Volume 99, Issue 1. Sage Publishing.