Life cycle environmental impacts of bioethanol production from sugarcane molasses in Iran

Abstract

In recent years, bioethanol from sugarcane molasses has been produced on an industrial scale in Iran. The aim of this study was to evaluate molasses-based bioethanol production from an environmental point of view. Data were collected from Debel Khazai agro-industry situated in southern region of Iran by using face-to-face interviews and annual statistics of 2010 to 2016 (6-year life cycle of sugarcane cultivation). Ten impact categories including abiotic depletion (AD), acidification (AC), eutrophication (EP), global warming potential (GWP), ozone layer depletion (OLD), human toxicity (HT), freshwater aquatic ecotoxicity (FE), marine aquatic ecotoxicity (ME), terrestrial ecotoxicity (TE), and photochemical oxidation (PO) were selected based on CML methodology. Inventory data for production of the inputs were taken from Ecoinvent, BUWAL 250, and IDMAT 2001 databases. The results revealed that in sugarcane cultivation process, electricity and trash burning were the most important contributors to all impact categories except OLD and TE. In industrial phase, natural gas had the highest contribution to the most impact categories. Greenhouse gas (GHG) emission for production of 1000 L molasses-based bioethanol was 1322.78 kg CO eq. By comparing total GHG emissions from 1000 L bioethanol to gasoline, the net avoided GHG emissions came out at 503.17 kg CO eq. According to results, it is clear that with increasing irrigation efficiency and improving performance of heating systems in industrial phase, environmental burdens would be significantly reduced.

Environmental and economic analysis of bioethanol production from sugarcane molasses and agave juice

“…Several recommendations for making bioethanol from sugarcane molasses and agave juice more environmentally friendly could be considered. One of the greatest challenges to meet is making the raw material more productive without damaging the ecosystem (Farahani and Asoodar 2017 , Osei et al 2003 , Papong et al 2017 , Silalertruksa and Gheewala 2009 , Steiner et al 2007 ).…”

“…For sugar and agave juice extraction, coal-produced energy was primarily responsible for the negative environmental impact. In this respect, it is recommended substituting coal with another fuel or using renewable energy such as biomass or hydraulic energy (the most widespread in Veracruz, Mexico) (CEMAD 2016 , Farahani and Asoodar 2017 ) as this reduces GHG emissions and environmental damage in sugar extraction.…”

“…Apart from this strategy, using vinasse as compost may significantly reduce environmental damage. It is also essential to capture and store any CO 2 given off on producing bioethanol by means of carbon capture and storage technology (CEMAD 2016 , Farahani and Asoodar 2017 , Laude et al 2011 , Silalertruksa and Gheewala 2009 ).…”

Life cycle assessment of the agricultural sector in Iran (2007–2014)

“…LCA procedure is described by ISO 14040‐44 . This method can be classified into four steps . These are described in the following sections:…”

Life cycle assessment of a bioelectrochemical system as a new technological platform for biosuccinic acid production from waste

“…Supported by ISO standards (ISO 2006a, b), Life cycle assessment (LCA) is a tool which enables the quantification of the potential environmental impacts of a product or a process throughout its life cycle. LCA has been widely used to assess goods, services, processes including processes in their early development in an eco-design approach (Azapagic 1999;Patel et al 2012;Espinosa et al 2015;Mitterpach et al 2017;Farahani and Asoodar 2017). However, a comparative LCA of non-mature systems with other systems, either non-mature or already up-scaled, is not an easy task because of the lack of step back and sufficient available data for a relevant LCA.…”