SPECIAL WORKS
Veolia Water Technologies helps food manufacturer to eliminate hydrogen sulphide
As part of a long-term partnership, Veolia Water Technologies has supplied its Hydrex 6935 chemical solution to solve an emerging issue with hydrogen sulphide in the water treatment system at a food manufacturer’s site. The application of the specially formulated water treatment chemical provided immediate results to an issue that was concerning staff at the site.
Veolia Water Technologies has provided a range of services to the business over the last decade, including supplying effluent treatment chemicals and servicing the Dissolved Air Flotation (DAF) water treatment plant at its facility.
In July 2023, the site began experiencing an issue with a foul odour. Staff at the factory had begun reporting a sulphur smell in certain corridors and staff areas within the building, which was initially believed to be an issue with the drains leading from the staff facilities.
The on-site team tried to solve the problem by cleaning and surveying the pipe network. The problem was eventually traced back to the wastewater treatment system on site, some distance from the factory.
As the manufacturer’s water treatment partner, Veolia Water Technologies was contacted to help the team find a solution. Veolia Water Technologies identified the cause as hydrogen sulphide build-up in the sump where treated water from the DAF unit is stored before being discharged to the public sewer. The low flow and long retention times in the system meant that hydrogen sulphide had developed in the water. Although the on-site team carried out daily testing of the water from the DAF plant, the presence of hydrogen sulphide downstream could not be detected.
Hydrogen sulphide is a colourless gas that has a characteristic sulphurous odour. While hydrogen sulphide is toxic, it is not dangerous in low concentrations but can still produce the highly unpleasant smell.
56
Hydrogen sulphide is created by microbes breaking down organic matter under anoxic (oxygen-free) conditions. It often occurs in water that stagnates for a long period of time.
Veolia Water Technologies recommended adding its Hydrex 6935 water treatment chemical to the wastewater stream to correct the issue. Formulated specifically for this purpose, Hydrex 6935 breaks down the hydrogen sulphide into more inert substances, which eliminates the odour. It also stabilises the water to prevent further formation of hydrogen sulphide. Hydrex 6935 requires no specialist dosing equipment and is easy to manage, meaning minimal cost and disruption to the site and simple on-going operation.
The first step was to carry out a trial of the Hydrex 6935 chemical and the result was immediate. Within 30 minutes, the smell had reduced substantially. The Veolia Water Technologies team set up the dosing equipment and provided training to allow the on-site team to manually add the small doses required. Since
| May 2025 |
draintraderltd.com
implementing the Hydrex solution there has been no recurrence of the issue.
Brian Jones, Business Development Manager at Veolia Water Technologies said: “Our work with this long-term client is an excellent demonstration of how effective Hydrex 6935 is in addressing the issue of hydrogen sulphide in wastewater. Some facilities use aerosol spray systems to mask the odour, but this is often ineffective and does not treat the underlying cause. Hydrex 6935 safely and quickly neutralises the compound and can be easily applied on a range of different water treatment systems.”
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76 |
Page 77 |
Page 78 |
Page 79 |
Page 80
