Sweden has started to implement improvements in sewage treatment for pharmaceutical and other micropollutant removal but is focused mainly on developing its policy for future action. Keith Hayward spoke with Christian Baresel of research institute IVL, which has been providing input on wastewater treatment needs and options, and contributed one of the reports supporting the recent recommendation by the Swedish Environmental Protection Agency for action on pharmaceuticals.
There are two important messages contained in the recent report by the Swedish Environmental Protection Agency to the country’s government on advanced wastewater treatment for removal of pharmaceuticals and other micropollutants. The first is that the agency sees the issue of being of sufficient concern that it recommends action be taken. The second is that action in the form of the addition of more advanced treatment at sewage works is viable.
Input to the report on the treatment options has come in particular from Swedish research institute IVL, especially through a key report it prepared specifically for the latest EPA report. Dr Christian Baresel was part of the team that prepared the IVL report. The work included setting out costs associated with different advanced treatment options. ‘[The costs] are based on our experiences in Sweden. We also used information from more than 40 installations in Germany, for example,’ he explains. ‘I think the costs are really viable.’
Assessing advanced options
This message of viability is important given what lies behind the statement. In particular, the report looked at pharmaceuticals. It also looked at another key current concern for the government – microplastics. More than this, it looked more widely at other pollutants. ‘We have done screening for many, many years – not only in Swedish treatment plants, but also in others,’ says Baresel. Other contaminants are likely to require action, so he says it does not make sense to target them separately with individual treatment steps. ‘That’s just not really resource efficient,’ he adds.
The report therefore includes an assessment of how well different technologies are able to tackle a wide range of contaminants of concern, explains Baresel. These include, for example, the issue of antibiotic-resistant bacteria.
The assessment is focused in terms of the number of substances actually considered. In the case of pharmaceuticals, for example, Baresel puts the total number of medical substances entering Swedish treatment plants at more than 2000. There is therefore a focus on the most important indicator substances, including ones found in high concentrations and others that may have a chronic effect at low concentrations over a long period of time. Baresel sees this can provide a basis for assessing treatment performance. ‘We have to analyse only a few in order to see if the treatment plant works or not,’ he says.
There is extra focus on Swedish conditions given, for example, that most wastewater sludge in the country goes to agricultural land. This contrasts with Germany, where there is more of a focus on use of sludge in incineration or thermal processing. Baresel explains that powdered activated carbon is one option for removing pollutants. ‘It’s the preferred option in Germany,’ he says. However, it ends up in the sludge, which would count against use of the sludge on land. ‘That is quite an important aspect for Sweden,’ he adds.
The overall findings in terms of technology options are summed up in the figure. This highlights technologies that are currently available, as well as emerging options.
There are questions around the cost of adding advanced treatment. ‘The actual cost of installing and operating the techniques are quite easy [to judge],’ says Baresel. More complex are the planning and permitting costs. ‘That is still a big issue in Sweden,’ he adds.
Sweden has just taken a big step forward with its first full-scale installation opening at Linköping, for which IVL carried out the pilot testing. For such early plants, the additional costs will be relatively high, but Baresel sees that over time this will reduce. ‘We can use all the experience on the other ones, so the cost for planning and everything else will be much lower,’ he says.
The way ahead
The message in terms of treatment technologies is that there are viable options. But this does not simply mean that there is a one-size-fits all solution for all treatment plants.
- Sweden, IVL, pharmaceuticals, micropollutants, microplastics