A recent research paper – ‘Pandemic danger to the deep: The risk of marine mammals contracting SARS-CoV-2 from wastewater’ – showed how COVID-19 in wastewater could infect aquatic mammals, serving as a reminder of the environmental risks posed by unsterilised wastewater.
While the UK’s wastewater treatment infrastructure mitigates most of this threat, some buildings require on-site wastewater disinfection integrated into their drainage system. Examples of this include sites working with genetically modified organisms or dangerous microbes, or any site discharging wastewater into environmentally sensitive locations.
Historically, wastewater has been disinfected in Chemical Effluent Decontamination Systems (EDS) using a hazardous and aggressive chemical sterilants.
These substances require specialist storage, regular renewal, and manual handling. Once the wastewater has been sterilised in a holding tank, disinfectant neutralisers —which carry their own risks and requirements— must be added before wastewater is disposed of.
Alongside the health risks of this sterilisation method, there are other shortcomings. While the procedure eradicates most micro-organisms from effluence, hardier bacteria and viruses may survive. Furthermore, harmful sterilants and neutralisers can remain in the effluence, potentially contaminating downstream watercourses.
A safer and more cost-efficient mechanism lays in Thermal EDS, which employ steam generators to sterilise wastewater by heating it to over 121°C. Installed into the lower floors of facilities, these devises require no manual input and little maintenance.
These steam-heated devices are more thorough than chemical sterilisers, capable of eradicating all bacteria, viruses, and microbiology that enter them. Effluence leaving a thermal EDS is not only completely sterilised, but also has no hazardous additives.
Thermal EDS function in a similar way to autoclaves; devices that use heat and pressure to sterilize materials. Astell Scientific Limited, an autoclave manufacturer with a 137-year pedigree, produces steam-heated EDS under the brand name of AstellBio.
“We are proud to provide a cleaner and simpler method of decontaminating waste, which is more hassle-free and requires fewer support facilities than alternative methods,” said AstellBio’s Sales and Marketing Director, Paul Birchmore.