As a professor of Environmental Engineering and Recycling, my field of activity is global. Even during my studies, I worked internationally, in Algeria. I have done research mainly on water and waste management in urban/rural areas and industries, for technical and practical development, and use in society. In 1997 I established the international conference Linnaeus Eco-tech, which originally focused on the countries around the Baltic Sea but now also counts participants from many countries outside the Baltic region and other parts of the world. Together with researchers from St. Petersburg State Technical University, we sat up the youth international conference Eco-Baltica, running since 1996. I have seen my work as peacekeeping which I still do. The Baltic Sea, in the20th century once a sea of war, I still hope now can be the place where former enemies cooperate for peaceful purposes. Emissions and gases don’t stop at borders, but with concerted efforts, much good can be done. Among all the countries in the world where I have worked is my second home Brazil, where I am linked both for research reasons and by personal ties. The boy from the little village Trekanten now has the world as his field of work. The book presents his life and some important parts of his research and scientific production.

Som professor i miljöteknik och återvinning är mitt verksamhetsområde globalt. Även under mina studier arbetade jag internationellt, i Algeriet. Jag har forskat främst om vatten- och avfallshantering i stad/landsbygd och industrier, för teknisk och praktisk utveckling och användning i samhället. 1997 etablerade jag den internationella konferensen Linnaeus Eco-tech, som från början fokuserade på länderna runt Östersjön men som nu också inberäknar deltagare från många länder utanför Baltikum och andra delar av världen. Tillsammans med forskare från St. Petersburg State Technical University arrangerade vi den internationella ungdomskonferensen Eco-Baltica, som pågått sedan 1996. Jag har sett mitt arbete som fredsbevarande, vilket jag fortfarande gör. Östersjön, som på 1900-talet en gång var ett krigets hav, hoppas jag fortfarande kan bli den plats där tidigare fiender samarbetar för fredliga ändamål. Utsläpp och gaser stannar inte vid gränserna, men med gemensamma insatser kan mycket gott göras. Bland alla länder i världen där jag har arbetat finns mitt andra hemland Brasilien, där jag är knuten både av forskningsskäl och av personliga band. Pojken från den lilla byn Trekanten har nu världen som sitt arbetsfält. Boken presentera hans liv och viktiga delar av hans forskning och vetenskaplig produktion.

During a survey on the island of Öland in south-eastern Sweden, whose aim was to study the local waste-disposal practices, the authors recorded abandoned machinery and cars dating from the 1940s to today in locations close to residential areas and farms, and complemented the investigation by interviewing informants. This led them to conclude that dumping redundant objects in the surroundings of villages forms an entangled network with other behaviour, i.e. collecting things which had outlived their usefulness and embedding them in the landscape. The behaviour observed in Öland is compared with two other cases of collecting abandoned objects in Öland and southern Sweden. Using the location and chronology of the finds, the authors interpret the behaviour by borrowing the concept of heterotopia, as defined by Foucault.

The present work discusses the problems and management options of beach wrack and dredged sediments. Beach wrack and dredged sediments near the shores have affected the coastal ecosystem, badly. The piles of beach wrack residues might be a significant emitter of greenhouse gases (GHGs) and dredged sediment is a substantial source of heavy metals and other pollutants. The recovery of valuable resources such as metals and nutrients from these so-called "wastes" is a sustainable strategy to enhance the resilience of the coastal ecosystem and management. The beach wrack meadows can be a potential source for green energy production. Even the demand for biodegradable polymers can be supplied by utilizing the waste beach wracks. The residues of beach wrack species like Posidonia oceanica, Zostera marina, Ulva spc. and Enhalus acorodies can be very beneficial species in terms of economic growth. Red algae have been the most favored and efficient candidate for methane yield. In case of dredged sediment, dewatering of sediment is an essential step for successful resource extraction. Although, extraction methods are almost similar to that applied for soil treatment, which includes pretreatment, physical partitioning, washing, thermal treatment, biological extraction, and immobilization. The fractionation study can be a beneficial tool for determining the metal species present in the sediment. Immobilization techniques are successful but continuous monitoring is required. The vitrification technique is highly effective but very expensive. Thermal treatment is useful for volatile metals such as mercury (Hg), but costs are high. Biological extractions are comparatively cheap but time-consuming. Henceforth, very few extraction methods are available for sediment and required further advancement in this field.

In this research, biogas production potential from beach wrack collected in Riga Gulf (Ragaciems, Jaunķemeri, Bigauņciems) and in coastline of Sweden (Kalmar) was studied using an anaerobic digestion method. Selected beach wrack masses laying ashore and containing macroalgal biomass of common macroalgae types specific to the Baltic Sea were mixed for consolidated samples. Anoxic fermentation of untreated beach wrack was carried out in 16 bioreactors applying a single filling mode at 38 °C. The study revealed that by utilizing beach wrack accumulated ashore as a feedstock for anaerobic digestion methane can be utilized if pretreatment and conditioning of the samples are performed. The study was continued for selected brown algae containing biomass tested with three dewatering pretreatment methods: a) keeping in tap water for 24 hours; b) washing with running fresh water for one hour, and c) drying to relatively constant weight. The resulting methane outcome was compared with the data corresponding to raw brown algae. The study confirmed that washing of macroalgal biomass applied as pretreatment prior to anaerobic fermentation avoids inhibition of salts and promotes biomethane production.

Global resource limits and increasing demand for non-fossil energy sources have expanded the research on alternative fuels. Among them, algal biomass is designated as a third-generation feedstock with promising opportunities and the capability to be utilized for energy production in the long term. The paper presents the potential for converting beach wrack containing macroalgal biomass into gaseous fuel as a sustainable option for energy production, simultaneously improving the organic waste management that the coastline is facing. Beach wrack collected in the northern Baltic Sea region was converted by gasification technology applicable for carbon-based feedstock thermal recovery, resulting in syngas production as the main product and by-product biochar. Proximate and ultimate analysis, trace and major element quantification, detection of calorific values for macroalgal biomass, and derived biochar and syngas analysis were carried out. A higher heating value for beach wrack was estimated to be relatively low, 5.38 MJ/kg as received (or 14.70 MJ/kg on dry basis), but produced syngas that contained enough high content of CH4 (42%). Due to macroalgal biomass specifics (e.g., high moisture content and sand admixture), an adjusted gasification process, i.e., the combination of thermochemical procedures, such as mild combustion and pyrolytic biomass conversion, might be a better choice for the greater economic value of biowaste valorization.

Dredging of sediments is conducted worldwide to maintain harbours and water bodies. As a result, large amounts of materials generated require proper management and could have useful applications in a circular economy context. The current use of peat as organic material in cultivating plants requires urgent replacement by more sustainable alternatives. In this context, using nutrient-rich sediments generated by dredging could be an attractive option. However, due to contaminants in dredged sediments, more investigations are required. The present study investigated the potential to employ dredged material as a plant-growing substrate to cultivate lettuce (Lactuca sativa). The study employed compost and dredged sediments from Malmfj & auml;rden Bay, Sweden, with low and high nutritional content(LN and HN, respectively), with and without polymer (PO) used for dewatering. The tests were carried out under con-trolled conditions in a greenhouse, and the studied substrates were (% vol): (1) 100 % sediment (100S(HN)); (2) 50 %sediment +50 % compost (50S(LN)-50C); (3) 70 % sediment +30 % compost (70S(LN)-30C); (4) 50 % polymer sediment+50 % compost (50S(PO)-50C);and (5) 100 % compost (100C). Fertilisers were added to 50S(LN)-50Cand 70SLN-30C during the experiment. Lettuces with the highest weight were harvested from substrates 100C, 50S(PO)-50C and 50S(LN)-50C.However, the lettuces only reached a weight of 18.57 +/- 4.67 g. The results showed that a main limitation of the growth was probably a lack of aeration of the sediments during sampling and development of the experiment. The low aeration possibly caused a lack of available forms of N in the substrates, hindering the growth. Lettuces harvested from substrates containing sediments presented Cd concentrations slightly overpassing the Swedish thresholds, and the health risk index was marginally exceeding 1. Hence, sediments need to be pre-treated before using them to cultivate edible crops, or they could be employed to cultivate ornamental or bioenergy plants

In this study, the ecotoxicological effects posed by bulk of the material obtained from landfill mining, that is, fine fraction (<10 mm), were assessed by performing bioassays tests with the aim of using the data in geoenvironmental applications, such as landfill biocover to control residual methane emissions from old landfills. Attention is mainly focused on the possible interaction of fine fractions with the test organism. The tested eluates of fine fraction exhibited low acute toxicity toward the bacteria Allivibrio fischeri and Escherichia coli, the marine rotifer Brachionus plicatilis, and brine shrimp Artemia salina. The eluates showed slight inhibitory effects on the germination of seeds of lettuce Lactuca sativa L. and timothy Phleum pratense L., and no inhibitory effects on germination of seeds of perennial ryegrass Lolium perenne L. The fine fraction studied in the present study can be characterized as acutely nontoxic or slightly acutely toxic. Correlation analysis revealed moderate positive correlation between lethality of rotifers and soluble content of organic compounds in the fine fraction eluates. In conclusion, the conducted experiments demonstrated that the usage of fine fraction for onsite applications such as landfill biocover may pose minimal environmental consequences, based on the ecotoxicity assessment. (C) 2022 American Society of Civil Engineers.