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Works focusing on micro- and nanoplastics analysis in drinking water by means of Raman microscopy have been raising in recent years, however a standardised protocol is still lacking. Moreover, at the best of our knowledge, no paper among them proposed a reliable way to calculating the particles masses. The current research aims to fill this gap by presenting a new analytical method employing Raman microscopy, applied to drinking water samples from a Danish facility. This work supports the above mentioned view and offers a comprehensive application of such principles, with the authors stressing the pivotal role of method validation when dealing with micro- and nanoplastics analysis.

The formation and release of odorous gasses such as hydrogen sulphide from sewer systems have intensified over the last years concurrently with the centralisation of wastewater treatment plants (Hvitved-Jacobsen et al., 2013). Hydrogen sulphide is toxic at low concentrations, and the formation of hydrogen sulphide can result in high cost for rehabilitation and maintenance following biogenic concrete corrosion. Different technologies are applied to prevent hydrogen sulphide emissions where injecting chemicals to either prevent the formation or remove formed sulphide are among the most common ones (Hvitved-Jacobsen et al., 2013). However, the European Parliament has expressed support for the employment of nature-based solutions due to the politic aim for a more sustainable society. Therefore, this paper's underlying theme focuses on a full-scale technical plant based on biological hydrogen sulphide treatment in Aarhus, Denmark.The plant receives air discharge from a sewer system that is then neutralised by mussel shell, which functions as a lime-based filter medium. This technology uses the same bacteria that cause hydrogen sulphides corrosion in sewers but moves the process from the concrete assets and over to the filter medium. This paper takes its onset in the full-scale facility design and uses the loadings and experiences to demonstrate the effectiveness of different lime-based filter media on hydrogen sulphide through an experimental column setup. The different lime-based filter media used in this setup are mussel shells, chalk pellets, crushed concrete and lava stone. The removal rate of hydrogen sulphide in each filter medium is investigated, and each filter medium's functionality is assessed. Hydrogen sulphide is injected in the inlet in concentrations of 50 ppm, 100 ppm, 350 ppm and 750 ppm to simulate various scenarios. When hydrogen sulphide reacts with the lime-based mediums, gypsum is created. The columns are therefore flushed with water comparable to the watering system in the technical plant. A hydrogen sulphide sensor is installed to monitor the columns' hydrogen sulphide transformation.The experimental setup results are finally compared to what is achieved at the full-scale facility in Aarhus, presenting data from both systems.

This report has been prepared by Lucia Margheritini mluc@build.aau.dk as midterm status report for the Velux project Anthropogenic Chemicals in North Jutland Coastline Sediments. This report presents the results from the “first round” of sampling. At present time the “second round” of sampling is practically concluded and we must analyse the collected sediments for heavy metals, PAHs and TBTs. The laboratory tests on the feasibility of the remediation technology and the capacity of catalysing heavy metals have been stopped for the second time due to Covid-19 restrictions. At the end of the report we provide a new time table for the project based on the latest developments. The projected, approved in July 2018 and initially ending in January 2021, was then extended, due to covid19 to June 2021. This report has been prepared by Lucia Margheritini mluc@build.aau.dk as midterm status report for the Velux project Anthropogenic Chemicals in North Jutland Coastline Sediments. This report presents the results from the “first round” of sampling. At present time the “second round” of sampling is practically concluded and we must analyse the collected sediments for heavy metals, PAHs and TBTs. The laboratory tests on the feasibility of the remediation technology and the capacity of catalysing heavy metals have been stopped for the second time due to Covid-19 restrictions. At the end of the report we provide a new time table for the project based on the latest developments. The projected, approved in July 2018 and initially ending in January 2021, was then extended, due to covid19 to June 2021.

The use of sacrificial concrete sewers for controlling sulfide related odor from sewers was investigated in this study. For the purpose of this study, three sacrificial concrete sewers were constructed with the intention of alleviating odor problems associated with discharging wastewater from force mains with extended hydraulic retention time. In all three locations, a 50 m long sacrificial concrete gravity sewer have been implemented in sparsely populated catchments. The monitoring campaign reported in this paper covers the first 5-7 years of operation. The results demonstrate the capability of the systems for reducing hydrogen sulfide gas (H2S(g)) concentrations in the sewer headspace. Based on the results of a sewer process model, the service life of the investigated sacrificial sewers were predicted to be several decades.

Vandsektorens udviklings-og demonstrationsprogram, VUDP, har støttet et projekt med det formål at fremtidssikre kloaknettet mod tæring og reducere omfanget af lugtgener. Projektet blev udført som et samarbejde mellem forsyningsselskaberne Hedensted Spildevand og Vejle Spildevand, Aalborg Universitet, rådgivervirksomheden DHI samt firmaerne Unisense og Bollerup-Jensen.

I perioden fra januar 2016 til december 2017 har virksomheden Hybridfilter A/S i samarbejde med Institut for Byggeri og Anlæg ved Aalborg Universitet gennemført projektet ”Hybridfilter for fjernelse af lugt- og drivhusgasser fra septiktanke og iltfri spildevandsnet”. Projektet var støttet af MUDP og havde til formål at udvikle filterløsninger, der med ét filter kan reducere frigivelse af både lugt- og klimagasser fra spildevandssystemer.

Rapporten viser, at sedimentet i regnvandssøer i byer spiller en væsentlig rolle for tilbageholdelsen af biocider, før regnvandet ledes ud i det naturlige vandmiljø.De konstruerede regnvandssøger og filterjorde er vigtige i forbindelse med afledning af regnvand fra byer, og de finder stadig større udbredelse i forbindelse med klimatilpasning og reduktion af byernes påvirkning af det naturlige vandmiljø. Rapporten viser i hvor stor udstrækning biocider tilbageholdeles og omsættes i regnvandssøer og filterjorde. Derudover blev det undersøgt, hvordan algesamfund i regnvandssøer påvirkes af biocider i afstrømmet regnvand. Rapporten peger endvidere på, at sedimentet i regnvandssøer bidrager væsentligt til en udligning af biocidkoncentrationer ved at tilbageholde biociderne under spidsbelastninger, og derpå igen frigive dem mere jævnt over en længere periode. Herved reduceres størrelsen af spidsbelastningerne med biocider til det naturlige vandmiljø, som regnvandet herefter udledes til. Der sker også en vis omsætning af biociderne i sedimentet, så der samlet sker en reduktion af biocidudledning til det naturlige vandmiljø. Alt i alt tydede undersøgelserne af alger i regnvandssøer på, at biocider i de undersøgte koncentrationer ikke førte til væsentlige ændringer i artssammensætningen. Regnvandssøer er dog påvirket af mange andre faktorer end biocider, så mulige effekter af biocider i afstrømmet regnvand kan derfor have været overskygget af andre typer af påvirkninger.

I forbindelse med projektet ”Svovlbrinte i kloaksystemer - årsager, konsekvenser og løsninger” er der udviklet en ny metode til at dokumentere tilstanden af kloakanlæg, der er udsat for svovlbrinterelateret betonkorrosion. Metoden kan i løbet af kort tid visualisere surhedsgraden af større overflader ved hjælp af en kemisk farvereaktion. På baggrund af denne information er det muligt at estimere betonelementernes nedbrydningshastighed og dermed deres restlevetid.