In the article, a qualitative and quantitative analysis of motor biofuels for water and land types of transport is carried out. In that context, the possibility of increasing their effi ciency is demonstrated through the introduction of the rapid pyrolysis process, which allows up to 25% of renewable fuels to be used in a mixture with conventional diesel. It is established that the most eff ective way is the joint processing of bio-oil with oil products on existing production facilities, which does not require the construction of new plants, signifi cantly reduces the dependence on fossil oil, and the obtained gasoline and diesel fuel have good performance characteristics and their use practically does not require changes in the fuel consumption infrastructure. Sažetak U ovome radu provedena je kvalitativna i kvantitativna analiza motornih biogoriva u vodenom i kopnenom prijevozu. U tom kontekstu prikazuje se mogućnost povećanja učinkovitosti goriva uvođenjem brzog procesa pirolize, kojim se 25% obnovljivih goriva može koristiti u mješavini s konvencionalnim dizelskim gorivom. Utvrđeno je da je najučinkovitiji način obrada bionafte zajedno s naftnim proizvodima u postojećim proizvodnim pogonima, što ne zahtijeva gradnju novih postrojenja, značajno smanjuje ovisnost o fosilnim gorivima, a dobiveno naftno i dizelsko gorivo pokazuju dobre izvedbene karakteristike, dok njihova uporaba ne zahtijeva promjene u infrastrukturi potrošnje goriva. KEY WORDS motor fuel pyrolysis bio-oil vacuum gasoil co-processing KLJUČNE RIJEČI motorno gorivo piroliza bionafta vakuum plinsko ulje koprocesuriranje

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In this work were analyzed factors and working conditions that leads to the wearing of junk mills tools that are a part of junk removal equipment used in drilling and workover of borehole. Such equipment is a part of oil and gas industry and work under condition of intense abrasive wearing with increased pressures and cyclic loads. Was established that traditional hardfacing materials based on the Fe-Cr-C system are not effective for improvement of abrasion resistance of elements of such equipment due to their low crack resistance and low hardness of chromium carbides. The aim of this work was to increase a durability of that equipment by using of flux cored electrodes with reaction components of pure metal powders, which leads to forming the fine-grained structure with increased hardness. Powders of Ti, Mo, B4C and their combinations were used. Structures of the hardfacing coatings were investigated by method of metallography, scanning electron microscopy (SEM). Abrasion wear tests were held under condition of fixed and non-fixed abrasion. Using of pure metal powders led to formation of a fine-grained structure with grains of Mo2FeB2 that forms around TiC, which work as modifier. It was investigated that the researched material based on Fe-Ti-Mo-C-B system that was used for increasing the wear resistance of junk mills led to increasing of the TBO period in 1.5-1.6 times comparing with serial hardfacing materials based on tungsten.