Fuel from waste animal fats

Abstract

The hunger of the modern human society for energy is tremendous, which is increasing with the increasing population and with the pursuit of higher standards of living. A significant proportion of this energy demand is made up by the different fuels which ensure mobility. Based on environmental and energetic considerations, a larger proportion of this energy is trying to be covered with renewable energy sources on the whole world. Recently mankind utilised the first generation of biofuels for the transportation sector (bioethanol and biodiesel), but the development has not stopped. Today, the second generation is on the border of utilisation (2nd gen. bioethanol and bio gas oil – mixture of iso and normal paraffins). In this article, we are focusing on the topic of 2nd generation bio derived Diesel fuel, the so-called bio gas oil. We are investigating the possibilities of the utilisation of a new, waste feedstock, namely the brown greases which are the products of rendering facilities, in co-process with high sulphur containing heavy gas oil (1.2% sulphur content). During our experiments we produced bio gas oil containing gas oil fraction via the most favourable process parameters of hydrogenation (T: 330–340°C, p: 50bar, LHSV: 1.0h−1) and isomerisation (T: 340°C, p: 50bar, 1.0h−1) of waste lard containing gas oil stream. We determined that these kinds of waste fatty materials can be appropriate feedstocks for the production of renewable diesel–fuel components. In addition, these materials are cheap, and their iLUC (indirect land use change) value is practically zero. The properties (cetane number: ⩾54, CFPP: −10 to −20°C, yield: >91%) of the product obtained after the two consecutive process steps met the valid standard for diesel fuel, thus we proved that this kind of waste feedstock can be an option for bio derived engine fuel production.