Biofuel as an alternative shipping fuel : technological, environmental and economic assessment

© Royal Society of Chemistry 2019Fossil derived fuels available for application within the maritime sector have been dominated by heavy fuel oil (HFO), which is conventionally used in low speed (main) engines, and more refined fuels such as marine diesel oil (MDO), which is consumed in fast or medium speed engines. However, increasing fuel costs and regulatory pressure such as the restrictions placed on sulphur content have increased interest in the use of alternative fuels. A number of alternative fuels have been identified and may be viable for use within the maritime sector including straight vegetable oil (SVO) as an alternative to HFO in low speed engines, biodiesel to replace MDO/MGO in low to medium speed engines and bio-liquefied natural gas (bio-LNG) in gas engines using LNG. The potential sources of biomass feedstocks, conversion pathways and technologies are identified. The key parameters limiting their potential application are examined, in particular, availability, technological development, technical integration, and operational consequences. A proposed solution to overcome these limitations is recommended. The effective implementation of these strategies will enable the more widespread use of biofuels in marine applications, significantly reducing emissions from ships and improving global air quality and also protecting the ecological environment.Peer reviewe

The optimal use of tris-2-ethylhexylamine to recover hydrochloric acid and metals from leach solutions and comparison with other extractants

This document is the Accepted Manuscript version of the following article: Uchenna Kesieme, Andreas Chrysanthou, Maurizio Catulli, and Chu Yong Cheng, ‘The optimal use of tris-2-ethylhexylamine to recover hydrochloric acid and metals from leach solutions and comparison with other extractants’, Journal of Environmental Chemical Engineering, Vol. 6 (2): 3177-3184, April 2018. Under embargo until 1 May 2019. The final, definitive version is available online via: https://doi.org/10.1016/j.jece.2018.05.001This paper describes the use of TEHA for HCl recovery from a leach solution generated by a hydrometallurgical plant. Four organic extractants were tested including TEHA, Alamine 336, Cyanex 923 and TBP. TEHA organic system performed best in terms of acid extraction, stripping and scrubbing efficiency. The successive extraction shows that more than 99% HCl was extracted after three stages of extraction. Scrubbing tests with different A/O ratios at different temperatures were conducted to identify the optimal conditions to separate HCl, Mn and Fe. After scrubbing the loaded organic solution at an A/O ratio of 1:4 and 22 °C, 94–100% of entrained metals were removed in a single contact with only 5.2% acid lost in the loaded scrub liquor. It was found that the phase disengagement time was in the range of 2– 4 min for both extraction and stripping, indicating reasonable fast phase separation. Based on these results from batch tests, it can be expected that after optimisation in a counter current circuit consisting of extraction, scrubbing, selective and bulk stripping, nearly all metals and HCl would be recovered and recycled.Peer reviewe

A review of acid recovery from acidic mining waste solutions using solvent extraction

This is the peer reviewed version of the following article: Uchenna Kesieme, Andreas Chrysanthou, Maurizio Catulli, and Chu Yong Cheng, ‘A review of acid recovery from acidic mining waste solutions using solvent extraction’, Journal of Chemical Technology and Biotechnology, (2018), which has been published in final form at https://doi.org/10.1002/jctb.5728. Under embargo until 1 July 2019. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.The minerals industry is increasingly being forced by regulatory and cost pressures to reduce the amount of liquid acidic waste they produce. This requires a strong focus on waste reduction by recycling, regeneration and reuse. Four mineral acids were examined for recovery from waste acidic solutions including H 2SO 4, HNO 3, HCl, and H 3PO 4. The selection of the optimal extractant for acid recovery was based on extraction, stripping and scrubbing efficiencies. The extractants suitable for the recovery of H 2SO 4 and HCl are in the order of TEHA > Cyanex 923 > TBP > Alamine 336. TEHA has the highest degree of acid extraction and stripping compared with Cyanex 923 and almost 99% of the acid can be stripped. Alamine 336 can extract higher acid (for H 2SO 4 and HCl systems) than Cyanex 923 and TBP. However loaded acid for Alamine 336 system cannot be stripped using water at 60°C. For the recovery of nitric and phosphoric acids from acidic waste effluents, TBP was the best option. This work clearly demonstrates that extractant suitable for acid extraction may not be suitable for its recovery. However such extractant may be applied for the removal of acid from any waste acidic solution sacrificing the back extraction of the loaded acid. The effective implementation of options for acid recovery was examined to improve sustainability in the mineral industry.Peer reviewe

Attributional life cycle assessment of biofuels for shipping: addressing alternative geographical locations and cultivation Systems

Crown Copyright © 2019 Published by Elsevier Ltd. All rights reserved.The purpose of this study is to evaluate a life cycle assessment of straight vegetable oil (SVO) and biodiesel addressing alternative upstream pathways. The pathways are SVO and biodiesel produced in the United Kingdom (UK) using European rapeseed and also, SVO and biodiesel produced in the UK using soybean grain and soybean oil imported from Argentina. Four environmental impact categories have been assessed using the SimaPro (ReCiPe life cycle impact assessment) method: this includes global warming potential (GWP); acidification; eutrophication and particulate matter. Rapeseed based biofuel had the lowest emission impact in terms of GHG emissions. Significant greenhouse gas (GHG) emissions can result from land use change due to the expansion and cultivation of soybean in Argentina. When land use change is not considered, the soy based biofuel system has the lowest GHG impact with more than 70% GHG emission reduction. The GHG emission at cultivation stage far outweighs the impacts of the other life-cycle stages irrespective of the feedstock used for the biofuel production systems. The use of fertilizers and associated soil emissions are the main contributors. The environmental impacts of biofuel can be reduced by avoiding land use change, improving soil management practices and yield, and also optimizing transportation routes. Effective implementation of options for biofuels production were explored to improve sustainability in shipping.Peer reviewe

The Use of New Media by Political Parties in the 2008 National Election

The overall purpose of this research project has been to undertake an empirical, exploratory study into how political parties in New Zealand make use of ICTs in and around the 2008 national election campaign, and their implications. The following research questions have been explored: How, in what form, and to what extent did political parties in New Zealand make use of ICTs during the 2008 national election? How can the use, and non-use, of ICTs be understood and explained? What are the implications of the uptake and use of ICTs by New Zealand political parties for their external relationships with voters? What recommendations can be made regarding the use of ICTs by New Zealand political parties for election campaigning

Mine waste water treatment and acid recovery using membrane distillation and solvent extraction

Waste waters produced and disposed of at modern mine sites are problematic because they contain hazardous substances (e.g. heavy metals, metalloids, acids, process chemicals), and therefore require treatment before disposing to the environment. Three different kinds of mine waters are identified depending on their chemical composition and pH. They are acidic mine waters, alkaline mine waters and neutral mine waters. Acidic mine waters are of interest because they have greater environmental hazards compared to others. Other acidic waste solutions also considered are waste streams from mineral processing plants and smelter sites. The current approaches to manage acidic waste solutions includes, neutralization, flocculation, filtration and bioremediation. However, acid and water recovery using current technologies has not proven to be viable as most of these processes fail to produce sufficient volume and quality of water whereas others do not provide the selectivity necessary to create valuable product streams suitable for recycle or re-use. In these processes, the by-product sludge can itself become a disposal problem. Therefore a novel approach to acid and water recovery are needed to improve the sustainability of the mining industry. The objective of this study is to explore the possibility for the novel combination of two technologies, membrane distillation (MD) and solvent extraction (SX) for water and acid recovery. The focus is the testing on acid and water recovery from industry spent acid streams and acidic mine wastes solutions and also modelling of the economic opportunities for MD to understand its cost sensitivities, in particular in the context of a carbon tax benchmarked against its more well-known application in seawater desalination

Assessment of supply interruption of rhenium, recycling, processing sources and technologies

© 2019 Elsevier Ltd. All rights reserved.Rhenium is a unique, valuable and extremely rare chemical element currently used as an alloying element in high-temperature superalloys for aerospace and industrial gas-fired turbines and also as a catalyst in petrochemical industry. Moving towards a more competitive and sustainable economy requires access to this metal in adequate quantities and at competitive costs. However, minerals containing rhenium are generally found in very small quantities and are currently not commercially viable sources. Thus, the method and route for the extraction of primary rhenium is dependent on other metals (copper, molybdenum and uranium) of which rhenium is a by-product. In addition, focusing on alternative sources such as recycling of rhenium from waste alloy scrap and catalysts, is continually gaining attention in the research community. This paper has focused on the assessment of secondary sources of rhenium. The historical cost and also supply interruption indicators of rhenium were examined and assessed. Finally, opportunities of recovering and reusing existing stocks through Industrial Ecology are discussed.Peer reviewe

Attributional life cycle assessment of biofuels for shipping: addressing alternative geographical locations and cultivation systems

The purpose of this study is to evaluate a life cycle assessment of straight vegetable oil (SVO) and biodiesel addressing alternative upstream pathways. The pathways are SVO and biodiesel produced in the United Kingdom (UK) using European rapeseed and also, SVO and biodiesel produced in the UK using soybean grain and soybean oil imported from Argentina. Four environmental impact categories have been assessed using the SimaPro (ReCiPe life-cycle impact assessment) method: this includes global warming potential (GWP); acidification; eutrophication and particulate matter. Rapeseed based biofuel had the lowest emission impact in terms of GHG emissions. Significant greenhouse gas (GHG) emissions can result from land use change due to the expansion and cultivation of soybean in Argentina. When land use change is not considered, the soy based biofuel system has the lowest GHG impact with more than 70% GHG emission reduction. The GHG emission at cultivation stage far outweighs the impacts of the other life-cycle stages irrespective of the feedstock used for the biofuel production systems. The use of fertilizers and associated soil emissions are the main contributors. The environmental impacts of biofuel can be reduced by avoiding land use change, improving soil management practices and yield, and also optimizing transportation routes. Effective implementation of options for biofuels production were explored to improve sustainability in shipping.</p

Economic analysis of desalination technologies in the context of carbon pricing, and opportunities for membrane distillation, Desalination 323

Abstract The economics membrane distillation (MD) and common seawater desalination methods including multi effect distillation (MED), multistage flash (MSF) and reverse osmosis (RO) are compared. MD also has the opportunity to enhance RO recovery, demonstrated experimentally on RO concentrate from groundwater. MD concentrated RO brine to 361,000 mg/L total dissolved solids, an order of magnitude more saline than typical seawater, validating this potential. On a reference 30,000 m 3 /day plant, MD has similar economics with other thermal desalination techniques, but RO is more cost effective. With the inclusion of a carbon tax of $23 per tonne carbon in Australia, RO remained the economically favourable process. However, when heat comes at a cost equivalent of 10$0.66/m 3 which is cheaper than RO and MED. The favour to MD was due to lower material cost. On low thermally, high electrically efficient installations MD can desalinate water from low temperature (&lt;50°C) heat sources at a cost of $0.57/m 3 . Our assessment has found that generally, MD opportunities occur when heat is available at low cost, while extended recovery of RO brine is also viable