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Pri korištenju biomase kao sirovine za proizvodnju goriva i toplinske energije, potrebno je odrediti njezina energetska svojstva. Primjenom modela umjetnih neuronskih mreža moguće je s velikom točnošću predvidjeti donju ogrjevnu vrijednost pojedinih energetskih kultura, čime se olakšava pronalaženje optimalnog rješenja. Sposobnost samoorganizacije, optimiziranog učenja i visoke tolerancije na pogreške neuronskim mrežama omogućuje pouzdano i precizno izračunavanje donje ogrjevne vrijednosti biomase. Ispravnom konfiguracijom mreže i prikupljanjem podataka, modeli umjetnih neuronskih mreža mogu se koristiti za predviđanje donje ogrjevne vrijednosti u realnom vremenu.

Lignocelulozni sastav energetskih kultura od velike je važnosti za određivanje energetskog potencijala biomase, kao i za koju vrstu biogoriva ju je bolje iskoristiti. Iz tog razloga cilj ovog rada bio je istražiti lignocelulozni sastav tri energetske kulture: miskantusa, divljeg prosa i virdžinijskog sljeza u dva roka žetve. Nakon provedenih analiza utvrđeno je da rok žetve značajno utječe na sadržaj vlakana u biomasi. Udio lignina se povećao odgodom žetve do proljeća, dok se ne može sa sigurnošću utvrditi utjecaj roka žetve na udio celuloze i hemiceluloze.

Problem zbrinjavanja mulja iz pročistača otpadnih voda na poljoprivrednim površinama je u ograničenju njegove primjene na površine koje nisu namijenjene proizvodnji hrane. Korištenje mulja u uzgoju energetskih kultura na tlima lošije kvalitete nepogodnima za proizvodnju hrane jedno je od rješenja za zbrinjavanje mulja. Cilj ovog rada je utvrditi razlike u energetskim svojstvima miskantusa nakon aplikacije Pravilnikom propisanih 1, 66 t ha-1 suhe tvari mulja iz pročistača otpadnih voda. Nakon provedenih analiza gorivih i negorivih tvari te ogrjevne vrijednosti utvrđeno je kako mulj ne utječe negativno na sastav biomase važnim za energetsku iskoristivost.

The first Directive on the promotion of renewable fuels was adopted in 2003 - Directive 2003/30/ EC of the European Parliament and of the Council of 8 May 2003 on the promotion of biofuels or other renewable fuels for transport. In 2009, a new (so called RED Directive, 2009/28/ EC) was adopted, which creates a legal framework to promote the use of energy from renewable sources. First generation biofuels require an increased share of arable land on which crops are grown for biofuel production. The Directive RED II limits the share of conventional biofuels to 7% and requires a minimum share of advanced biofuels from lignocellulosic feedstocks and waste in final energy consumption in the transport sector of at least 0.2% in 2022, 1% in 2025 and 3.5% in 2030.

The aim of this paper is to determine process differences of anaerobic digestion and digested residue by using different raw material input - solid by-products (bio-waste) after grape processing in wine production from varieties Žlahtina, Syrah and Debit. It was found that digested residue in all of the samples, from which all are mildly alkaline, contains a low level of dry matter, 70% of which is organic matter. Biogenic elements were present in moderate concentration while values of heavy metals were within approved limits. This analysis leads to the conclusion that digested residues of all input materials can be used in agricultural production, especially in plant production and grassland cultivation. Biogas production from wine processing by-product contributes to environmental preservation and good technological solutions in waste treatment, including waste transformation into useful energy. Therefore, biogas production from wine by-products could provide winemakers to become producers of electricity and heat energy which could reduce greenhouse-gas emissions and prevent methane emission from waste decomposition.

The purpose of the paper was to determine the quantity and composition of plate waste left over after the guests had consumed their meals in a res-taurant that serves only vegan meals and in restau-rant that serves dishes including food of animal origin. Both restaurants are located in Zagreb (Cro-atia) and the sample size was 500 plates. After meal consumption, each component was weighed sepa-rately. Subsequently, in-depth interviews were conducted with restaurant staff members. Out of the 500 plates served in the vegan restaurant, 377 were empty after the guests had finished their consump-tion. The remaining 123 plates contained 6, 951 g of plate waste. In the restaurant that serves meals containing meat, 264 out of the 500 serving plates remained empty. The remaining 236 plates contained 20, 966 g of plate waste. In addition, it was assessed whether the size of the portion caused an increase in amount of food waste. Namely, when portion size was larger than 410 g more plate waste was generated, but at the same time also more food was eaten. The results and research methodology could act as a useful guide for decreasing plate waste in restaurants and invoke a possible change of eating habits.

Otpad i gospodarenje s njime jedna je od glavnih tema današnjice. U otpad se ubraja sve što se nakon određene aktivnosti pojavljuje kao nusproizvod bez vrijednosti. Razvoj turizma, a time i ugostiteljstva, generira određene negativne učinke. Jedan od njih je neprikladno gospodarenje otpadom od hrane. Napori da se udovolji novim trendovima gospodarenja otpadom nisu dovoljni ukoliko se pravilno ne uvede sustav prevencije i odvojenog prikupljanja otpada koji nastaje u ugostiteljskoj djelatnosti. Cilj ovog istraživanja je utvrditi količinu otpada iz hrane koju proizvede ugostiteljski objekt te ga kvantificirati po kategorijama. Iz dobivenih rezultata utvrdilo se koja vrsta hrane preostale nakon konzumacije čini najveći udio u otpadu iz hrane. Mjerenjima se pokazalo koliko se otpada od hrane dnevno proizvede po jednom serviranom obroku. Rezultati mogu poslužiti kao smjernice za odgovorno zbrinjavanje ovakve vrste otpada u svrhu unaprjeđenja poslovanja istraživanog ugostiteljskog objekta. Waste and it's management is one of the main topics nowadays. In waste, we count all that occurs after a certain activity as a by-product with no value. Development of tourism, and therefore catering, generates certain negative effects, and one of them is inappropriate food waste management. Efforts to comply with new waste management trends are insufficient unless a system of prevention and separate collection of waste generated in the catering business is properly introduced. The aim of this study is to determine the amount of food waste produced by the catering facility and to quantify it by categories. From the obtained results, it was determined which type of food would later make the largest share of food waste. Measurements have shown how much food waste per day is produced per serving. The results can serve as guidelines for responsible disposal of this type of waste to improve the business of the researched catering facility.

Konoplja je kultura s vrlo širokom mogućnošću primjene. Nema velikih zahtjeva u uzgoju, a vrlo je korisna u plodoredu s drugim ratarskim kulturama. U globalnim gospodarstvima industrijska konoplja svoju glavnu primjenu ima u prerađivačkoj industriji prije svega papira, zatim tekstila, auto industriji, građevinarstvu, a široko se primjenjuje u restauratorskim zahvatima radi nekadašnjeg tradicijskog korištenja. Sjemenke konoplje koriste se i u prehrambenoj industriji. Za ljudsku hranu koristi se brašno i ulje od konoplje.