Livestock production is a potential environmental pollutan because of the high concentartions of animals on the small area. Production of biogas with anaerobic degradation from organic waste is one of the pledge alternative energetic solutions, especially from organic manure made from animal farming and other residuals of agricultural production.The aim of this paper was to determine posibillity of using manure different origin from extensive animal breeding for production of biogas in labaratory conditions. The results obtained will be based on posibillity of use waste streams from extensive animal husbandry as basic substrate for anaerobic digestion.In this regard, cosubstrates were formed as mixture 1 chicken excrement; mixture 2 sheep manure; mixture 3 cow manure; all three basic substrates were in mixture with the sludge from the wastewater treatment plant. The results showed production of 71,5 ml CH4/gVS for mixture 1, 68,65 ml CH4/gVS for mixture 2 and 48,68 ml CH4/gVS for mixture 3. KEYWORDS:extensive breeding, manure, anaerobic digestion, biogas, biomethane potentional

Water hardness and deposition of incrustation is a problem in households and industry. In this regard, several technologies have been developed with the purpose of water softening and preventing the deposition of incrustation. The ion exchange method is the most commonly used method and is considered a conventional method. However, due to the shortcomings of this method, there is a need to develop adequate alternative methods. The potential of the method using biosorbents such as moss Leucobryum glaucum and Spaghnum peat moss for the purpose of removing water hardness has recently become the subject of intensive research with growing interest. In this study, the method using Leucobryum glaucum as a biosorbent was tested and a comparison was made with the conventional method and previously conducted studies that used other biosorbents.

Pelotherapy is the application of thermal muds (peloids) for therapeutic purposes. Artificial peloids were prepared usingpyrophilite shale maturated in three different types of thermal water in terms of their pH values. The samples after 30and 60 days of maturation were examined by X-ray diffraction. No significant variations in the mineralogical compositionand diffractograms of pyrophillite peloids were detected after maturation. Only the influence of the maturation processof pyrophillite on the pH value of mineral water with high and low pH value is noticed.

Sludge generated in wastewater treatment processes must be treated in an adequate manner, and therefore disposed of in an environmentally friendly manner. The biggest obstacle to the efficient use of sludge is the high water content, therefore the development of methods to accelerate the sludge dewatering process is particularly important. For the purposes of the research, the waste sludge created in the process of purifying ammoniaphenol wastewater in the GIKIL factory was used. Sludge conditioning was performed by adding a commercial flocculant (0.1 % solution) in combination with pyrophyllite, kaolin clay and shredded cardboard. According to earlier research, the volume of waste sludge with the addition of a suitable flocculant could be reduced by more than 5 times compared to the initial amount, leaving behind a large amount of separated water that can be returned to the process. The results show that the addition of commercial flocculant in the amount of 0.8 % gives the best results (reduction of sludge volume by 78.8 %). A lower percentage was found in samples with a mixture of flocculants with pyrophyllite (78 %) and kaolin (77.6 %), while the combination of flocculants with waste cardboard was ineffective (64.4 %). Addition of flocculant to waste sludge resulted in a decrease in specific filtration resistance (1.15x107 s2/g). A decrease in specific resistance was also observed in flocculant/kaolin clay (0.8x107 s2/g) and flocculant/cardboard (1.09x107 s2/g) samples. Sludge conditioning also resulted in a reduction of suspended solids in the neonate compared to settled raw sludge without additives.

Biodiversity of diatoms and applicability of diatom indices in biomonitoring based on littoral epiphytic samples of Lake Modrac were investigated. Diatoms were taken mostly from Phragmites australis stems in 2017, during which physical and chemical parameters of the water were measured. A total of 85 diatom taxa were identified. Gomphonema (13 spp.), Navicula (11 spp.), and Nitzschia (8 spp.) were the most abundant genera. Obtained values of trophic indices (TID, TvD, and TDIL) pointed to meso- to eutrophic status for most localities, while values of the IBD, EPI, ?D, and IPS indices indicated good ecological status, except for localities at the mouth of 2 main tributaries which had moderate or poor ecological status. Based on the hierarchical group average clustering and nonmetric multidimensional scaling, 4 groups were identified, mainly related to the sampling period, with higher spatial variation in species composition during summer. Since environmental legislation in Bosnia and Herzegovina still does not provide detailed instructions on using diatoms in biological assessment, results of this study can be useful for the development of biomonitoring tools for lakes in Bosnia and Herzegovina.

Biodizel je naziv za gorivo dobiveno iz obnovljivih izvora koje se može upotrebljavati u nemodificiranim dizelskim motorima umjesto uobičajenog fosilnog dizelskog goriva. Biodizel je ustvari komercijalni naziv za smjesu metilnog estera, koja se danas može naći na tržištu tekućih goriva, prije svega u EU-u, gdje se i prodaje krajnjim korisnicima. Globalna proizvodnja biodizela u 2014. godini premašila je 30 milijardi litara od čega oko 39 % otpada na EU.1 Kao osnovna sirovina za dobivanje biodizela mogu poslužiti svi izvori biomase bogati triacilglicerolima. U prvom redu tu spadaju jestiva biljna ulja, zatim nejestiva, otpadna i upotrijebljena ulja, kao i životinjske masti. Metanoliza biljnih ulja može biti podijeljena na osnovu prisutnosti i vrste katalizatora ili topljivosti katalizatora u reakcijskoj smjesi. Ovisno o tome odvija li se reakcija metanolize s ili bez prisutnosti katalizatora, metanoliza može biti katalizirana i nekatalizirana. Kemijski katalizatori metanolize razlikuju se kako po svojoj prirodi tako i na osnovi njihove topljivosti u reakcijskoj smjesi. Ovisno o tome je li katalizator u reakcijskoj smjesi topljiv ili nije, kemijski katalizirana metanoliza može biti podijeljena na homogeno, heterogeno i homogeno-heterogeno kataliziranu metanolizu. Osnovna karakteristika homogeno katalizirane metanolize je otopljen katalizator u reakcijskoj smjesi. Homogeni katalizatori metanolize mogu biti lužine i kiseline. Najčešće istraživan i u komercijalnim procesima najčešće primjenjivan način dobivanja biodizela je metanoliza katalizirana lužinama. Proces transesterifikacije s lužnatim katalizatorom uobičajen je način proizvodnje biodizela iz rafiniranih biljnih ulja. Kao lužnati katalizatori najčešće se upotrebljavaju kalijev hidroksid (KOH), natrijev hidroksid (NaOH) i natrijev metoksid (NaOCH3). Unatoč brojnim prednostima homogeno katalizirane metanolize, glavni nedostatak joj je nemogućnost ponovne uporabe katalizatora. Pored toga, katalizator zaostaje u esterskoj frakciji, odakle ga je potrebno ukloniti, što se najčešće provodi višestrukim ispiranjem s vodom, a otpadna voda čini značajan problem za okoliš.2,3 Uporabom katalizatora koji se ne otapaju u reakcijskoj smjesi, pojednostavljuje se način izdvajanja i rafiniranja proizvoda, smanjuju okolišni problemi i omogućava ponovna uporaba katalizatora. Uporabom heterogenih katalizatora dobiva se kvalitetniji i čišći biodizel kao i glicerol, a zbog jednostavnijeg postupka i mogućnosti višestruke uporabe katalizatora danas se homogena kataliza sve više nastoji zamijeniti heterogenom.3,4,5 U posljednje vrijeme heterogeno katalizirana metanoliza vrlo se intenzivno istražuje. U različitim laboratorijskim istraživanjima heterogeno katalizirane metanolize upotrebljavan je velik broj različitih spojeva u funkciji katalizatora.6 Pri tome je mnogo pozornosti posvećeno istraživanju vrste, načina pripreme i količine heterogenog katalizatora, kao i uvjetima pri kojima se izvodi reakcija metanolize. Katalitička aktivnost heterogenih katalizatora ovisi o mnogo čimbenika, prije svega o njihovoj prirodi, veličini i specifičnoj površini čestica te primijenjenim uvjetima u kojima se reakcija izvodi.7 Između objavljenih rezultata ovih istraživanja postoje razlike oko optimalnih uvjeta procesa, pa čak i oko postojanja katalitičke aktivnosti nekih spojeva. Najveći broj istraživanja heterogeno katalizirane metanolize odnosi se na primjenu zemnoalkalijskih metala, točnije njihovih oksida kao katalizatora reakcije.3 Katalitička aktivnost oksida zemnoalkalijskih metala raste s povećanjem njihove bazičnosti i to redoslijedom;