Emissions of motor vehicles propelled by liquefied petroleum gas

Tema ovog rada su emisije ispušnih plinova motornih vozila pogonjenima plinom, te njihov utjecaj na okoliš, a ponajprije na osobnim vozilima (M1 kategorija) pogonjenim ukapljenim naftnim plinom (UNP). U radu su dati kratki opisi rada motora s unutarnjim izgaranjem pogonjenih plinovima koji se trenutno najviše koriste na hrvatskom, ali i svijetskom tržištu. Budući da se podaci o emisijama štetnih tvari i o ispravnosti sustava za naknadnu obradu ispušnih plinova ovakvih vozila nigdje u RH ne evidentiraju niti obrađuju, jer ne postoji zakonska osnova za to, cilj istraživanja je provjeriti kakav je njihov utjecaj na okoliš. Naime, takva vozila nisu u RH obvezna prolaziti Eko test pri redovitom tehničkom pregledu. U radu su objašnjene vrste pogonskih plinova koje postoje i koje se koriste u Republici Hrvatskoj, njihovi sastavi, sastavi emisija pri izgaranju istih, prednosti i nedostaci, te ostale bitne značajke vezane za motorna vozila pogonjena plinom. U planu rada je bilo provesti dva različita ispitivanja vozila, jedno od strane CVH (Centar za vozila Hrvatske), te drugo od strane Laboratorija za motore i vozila na FSB-u. Nažalost, zbog kratkog vremenskog roka, ispitivanje na FSB-u nije uspješno provedeno. Provedena ispitivanja od strane CVH su u suštini mjerenje emisija ispušnih plinova iz vozila pogonjenima UNP-om, te obrada dobivenih podataka. Posebno su interesantni podaci vezani na povijesne podatke. Pod time se misli na procjenu emisija u ovisnosti o prijeđenom putu vozila, odnosno starosti vozila. Očekuje se da će se iz analize rezultata moći utvrditi kakav utjecaj ima starost vozila pogonjenih UNP-om na emisije vozila. Kao prilog analizi ovog problema napravljena je analiza u programskom paketu Copert, koja prikazuje koliki utjecaj imaju ta vozila na ukupnu emisiju vozila u RH. Podaci o strukturi vozila potrebnih za takvu analizu su također dobiveni iz CVH, što pokazuje da je njihova pomoć bila od iznimnog značaja za nastanak ovog rada.This thesis outlines exhaust gas emissions of motor vehicles powered by gaseous fuels and their impact on the environment, especialy on passenger vehicles (M1 category) powered by liquefied petroleum gas (LPG). The paper gives a brief description of internal combustion engines powered by most commonly used gaseous fuels on the Croatian and global market. Since the data about emissions and proper functionining of exhaust gas after treatment systems for such vehicles is not registered nor processed in Croatia, as there is no legal basis for it, the goal of the research is to check their impact on the environment. In fact, in Croatia such vehicles are not required to pass the Eco test during regular technical inspection of the vehicle. In the thesis are descriptions of existing types of gaseous fuels that are used in Croatia, their compositions, compositions of their emissions produced by combustion, advantages and disadvantages of gaseous fuels and other important features related to motor vehicles powered by such fuels. The plan was to conduct two different vehicle tests, one by the Croatian Vehicle Centre (CVH), and the other by the Faculty of Mechanical Engineering and Naval Architecture in Zagreb (FSB) in their Laboratory for engines and vehicles. Unfortunately, due to a short period of available time, the test by FSB was not successfully conducted. The conducted tests by CVH are essentially measuring of exhaust gas emissions of vehicles powered by LPG, and processing of the resulting data. Particularly interesting are the data related to historical data. This refers to emissions evaluations depending on vehicle’s mileage, respectively vehicle’s age. It is expected that the results of the analysis will be able to determine what impact does the age of vehicles powered by LPG have on vehicle’s emissions. As a theoretical approach to this problem, an analysis has been made in a software package named Copert, whose analysis shows what impact these vehicles have on the total emissions of passenger vehicles in Croatia. Data about the vehicle structure in Croatia necessary for this analysis was obtained also from the CVH, which shows that their participation was of significant help for the making of this thesis