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As mentioned by Bacastow and Bellafiore, Geospatial Intelligence (GEOINT) is a field of knowledge, a process, and a profession. As knowledge, it is information integrated in a coherent space-time context that supports descriptions, explanations, or forecasts of human activities with which decision makers take action. As a process, it is the means by which data and information are collected, manipulated, geospatially reasoned, and disseminated to decision-makers. The geospatial intelligence professional establishes the scope of activities, interdisciplinary associations, competencies, and standards in academe, government, and the private sectors. Taking into account the fact that GEOINT is crucial for broad organizations, BLOM Group, a leading International provider within acquisition, processing and modeling of geographic information and ITHACA, a non-profit organization devoted to products and services delivering to the UN System in the field of geomatics, set up and provided GEOINT data to the main Italian companies operating in the field of mobile phone networking. This data, extremely useful for telecom network planning, have derived and produced using a standardized and effective (from the production point of view) approach. In this paper, all the procedures used for the production are described and tested with the aim to investigate the suitability of the data and the procedures themselves to any others possible fields of application.

Fatty acids are of particular interest for industrial applications of microalgal feedstock, as these have a wide array of different uses such as pharmaceuticals and biofuels. Fourier transform infrared (FTIR) spectroscopic techniques used in combination with multivariate prediction modeling are showing great potential as analytical methods for characterizing microalgal biomass. The present study investigated the use of diffuse reflectance Fourier transform infrared spectroscopy (DRIFTS) coupled with partial least squares regression (PLSR) to estimate fatty acid contents in microalgae. A prediction model for microalgal samples was developed using algae cultivated in both Bold's basal medium (BBM) and sterilized municipal wastewater under axenic conditions, as well as algal polycultures cultivated in open raceway ponds using untreated municipal wastewater influent. This universal prediction model was able to accurately predict microalgal samples of either type with high accuracy (RMSEP = 1.38, relative error = 0.14) and reliability (R2 > 0.92). DRIFTS in combination with PLSR is a rapid method for determining fatty acid contents in a wide variety of different microalgal samples with high accuracy. The use of spectral characterization techniques offers a reliable and environmentally friendly alternative to traditional labor intensive techniques based on the use of toxic chemicals.

Herein, a novel sulfur-doped carbon material has been synthesized via a facile and sustainable single-step pyrolysis method using lignin-sulfonate (LS), a by-product of the sulfite pulping process, as a novel carbon precursor and zinc chloride as a chemical activator. The sulfur doping process had a remarkable impact on the LS-sulfur carbon structure. Moreover, it was found that sulfur doping also had an important impact on sodium diclofenac removal from aqueous solutions due to the introduction of S-functionalities on the carbon material’s surface. The doping process effectively increased the carbon specific surface area (SSA), i.e., 1758 m2 g−1 for the sulfur-doped and 753 m2 g−1 for the non-doped carbon. The sulfur-doped carbon exhibited more sulfur states/functionalities than the non-doped, highlighting the successful chemical modification of the material. As a result, the adsorptive performance of the sulfur-doped carbon was remarkably improved. Diclofenac adsorption experiments indicated that the kinetics was better described by the Avrami fractional order model, while the equilibrium studies indicated that the Liu model gave the best fit. The kinetics was much faster for the sulfur-doped carbon, and the maximum adsorption capacity was 301.6 mg g−1 for non-doped and 473.8 mg g−1 for the sulfur-doped carbon. The overall adsorption seems to be a contribution of multiple mechanisms, such as pore filling and electrostatic interaction. When tested to treat lab-made effluents, the samples presented excellent performance.

Abstract Green microalgae is a possible feedstock for the production of biofuels, chemicals, food/feed, and medical products. Large-scale microalgae production requires large quantities of water and nutrients, directing the attention to wastewater as a cultivation medium. Wastewater-cultivated microalgae could via wet thermochemical conversion be valorised into products for e.g., water treatment. In this study, hydrothermal carbonization was used to process microalgae polycultures grown in municipal wastewater. The objective was to perform a systematic examination of how carbonization temperature, residence time, and initial pH affected solid yield, composition, and properties. Carbonization temperature, time and initial pH all had statistically significant effects on hydrochar properties, with temperature having the most pronounced effect; the surface area increased from 8.5 to 43.6 m2 g−1 as temperature was increased from 180 to 260 °C. However, hydrochars produced at low temperature and initially neutral pH generally had the highest capacity for methylene blue adsorption. DRIFTS analysis of the hydrochar revealed that the pH conditions changed the functional group composition, implying that adsorption was electrostatic interactions driven. This study concludes that un-activated hydrochars from wastewater grown microalgae produced at relatively low hydrothermal carbonization temperatures adsorb methylene blue, despite having low surface area.

Abstract Microalgal biomass may have biostimulating effects on plants and seeds due to its phytohormonal content, and harnessing this biostimulating effect could contribute to sustainable agriculture. Two Nordic strains of freshwater microalgae species Chlorella vulgaris and Scenedesmus obliquus were each cultivated in a photobioreactor receiving untreated municipal wastewater. The algal biomass and the supernatant after algal cultivation were tested on tomato and barley seeds for biostimulating effects. Intact algal cells, broken cells, or harvest supernatant were applied to the seeds, and germination time, percentage and germination index were evaluated. Seeds treated with C. vulgaris, in particular intact cells or supernatant, had up to 25 percentage units higher germination percentage after 2 days and an overall significantly faster germination time (germinated on average between 0.5 and 1 day sooner) than seeds treated with S. obliquus or the control (water). The germination index was higher in C. vulgaris treatments than in the control for both tomato and barley, and this was observed for both broken and intact cells as well as supernatant. The Nordic strain of C. vulgaris cultivated in municipal wastewater thus shows potential for use as biostimulant in agriculture, adding novel economic and sustainability benefits.

Biofuel production using microalgae is a renewable and environmental-friendly alternative to the use of fossil fuels. Microalgae storage lipids are promising resources for biofuel production. In this study, pure strains of the microalgae Scenedesmus dimorphus and Selenastrum minutum were grown in untreated municipal wastewater for six days under mixotrophic conditions. The algae strains were subjected to different stresses such as nutrient deprivation, and 5% (w/v) salinity to trigger lipid production and to study effect on FAME composition. The highest lipid concentrations were found in S. dimorphus (35 and 34%) and in S. minutum (40 and 39%) under nutrient deprivation and 5% salinity, respectively. On the one hand, salt stress decreased biomass production; on the other hand in both S. dimorphus and S. minutum salt stress significantly increased the concentration of saturated fatty acid (SFA) and it decreased the concentration of poly-unsaturated fatty acid (PUFA) contents, which are desirable for the production of good quality biofuel such as biodiesel. Hence our findings show how salt stress could clearly affect FAME composition in short time 1–3 days, greatly improving the FAME quality as source of biofuel.

In order to investigate environmentally sustainable sources of organic carbon and nutrients, four Nordic green microalgal strains, Chlorella sorokiniana, Chlorella saccharophila, Chlorella vulgaris, and Coelastrella sp., were grown on a wood (Silver birch, Betula pendula) hydrolysate and dairy effluent mixture. The biomass and lipid production were analysed under mixotrophic, as well as two-stage mixotrophic/heterotrophic regimes. Of all of the species, Coelastrella sp. produced the most total lipids per dry weight (~40%) in the mixture of birch hydrolysate and dairy effluent without requiring nutrient (nitrogen, phosphorus, and potassium—NPK) supplementation. Overall, in the absence of NPK, the two-stage mixotrophic/heterotrophic cultivation enhanced the lipid concentration, but reduced the amount of biomass. Culturing microalgae in integrated waste streams under mixotrophic growth regimes is a promising approach for sustainable biofuel production, especially in regions with large seasonal variation in daylight, like northern Sweden. To the best of our knowledge, this is the first report of using a mixture of wood hydrolysate and dairy effluent for the growth and lipid production of microalgae in the literature.

Algae are without doubt the most productive photosynthetic organisms on Earth; they are highly efficient in converting CO2 and nutrients into biomass. These abilities can be exploited by culturing microalgae from wastewater and flue gases for effective wastewater reclamation. Algae are known to remove nitrogen and phosphorus as well as several organic contaminants including pharmaceuticals from wastewater. Biomass production can even be enhanced by the addition of CO2 originating from flue gases. The algal biomass can then be used as a raw material to produce bioenergy; depending on its composition, various types of biofuels such as biodiesel, biogas, bioethanol, biobutanol or biohydrogen can be obtained. However, algal biomass generated in wastewater and flue gases also contains contaminants which, if not degraded, will end up in the ashes. In this review, the current knowledge on algal biomass production in wastewater and flue gases is summarized; special focus is given to the algal capacity to remove contaminants from wastewater and flue gases, and the consequences when converting this biomass into different types of biofuels.

Rapid rises in atmospheric CO2 levels derived from fossil fuel combustion are imposing urgent needs for renewable substitutes. One environmentally friendly alternative is biodiesel produced from suitable microalgal fatty acids. Algal strains normally grow photoautotrophically, but this is problematic in Northern areas because of the light limitations for much of the year. Mixotrophic and particularly heterotrophic strains could be valuable, especially if they can be cultivated in municipal wastewater with contents of nutrients such as nitrogen and phosphorous that should be reduced before release into receiving water. Thus, the aim of this study was to screen for microalgal strains suitable for heterotrophic cultivation with a cheap carbon source (glycerol) for biodiesel production in Nordic, and other high-latitude, countries. One of the examined strains, a Desmodesmus sp. strain designated 2-6, accumulated biomass at similar rates in heterotrophic conditions with 40 mM glycerol as in autotrophic conditions. Furthermore, in heterotrophic conditions it produced more fatty acids, and ca. 50% more C18:1 fatty acids, as well as showing a significant decrease in C18:3 fatty acids, all of which are highly desirable features for biodiesel production.