- by Trevor Loveday
Researchers probe land, water and air pollutant control
UK Water Industry Research (UKWIR) has published three reports with accounts on options for storm overflows; the effectiveness of carbon removal through biosolids; and air pollution in wastewater treatment.
UKWIR reported that space and road access were limiting factors for storm overflow solutions and lack of access to power limited options available for organic pollution removal, disinfection and removal of emerging contaminants. Biological treatment, including nature-based solutions, were “challenging due to the intermittent nature of storm overflows”.
UKWIR said “The prevention of rainfall entering the sewer in the first place should be the first option considered any situation before considering the most infrastructure heat options of storm separation, storage or treatment.
UKWIR said findings in the report included: quantification of the current emissions associated with wastewater and bioresources treatment; key areas for further investigation; and potential mitigation measures.”
It said there was “little data available to quantify how significant the five most damaging air pollutants addressed in the government’s Clean Air Strategy: ammonia, nitrogen oxides, sulphur dioxide particulate matter and non-methane volatile, organic compounds. So in an initial step towards achieving the Clean Air Strategy, UKWIR commissioned Atkins to establish the potential sources of the five pollutants and quantify the impact at local and national levels.
Biosolids recycling to agricultural land, according to UKWIR, is considered the best practicable environmental option providing a valuable source of nutrients and organic matter that also offset greenhouse gas emissions produced during artificial fertiliser manufacture.
But knowledge of carbon storage and the factors controlling emissions following biosolids recycling to agricultural land was, UKWIR said, required. Its findings included the rate of increase in the organic carbon content of soil depended on factors including soil type, initial soil carbon content, climate, land use and the frequency of application as limited by nitrogen and phosphorus content.