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Biodiesel production from algae grown on food industry waste water
2014
Mureed, K.
Energy crisis is a worldwide problem; Pakistan is facing severe shortage of this, especially in summer. To overcome these crises, huge amount of fossil fuels is being utilized which ultimately resulting in their exhaustion. In order to cope up the increasing energy requirements, alternative energy sources are required that should be cost-effective, environment friendly and technically feasible. In this scenario biodiesel production from algae has attracted scientist's attention worldwide. At present, the major constraint in biodiesel production from algae is nutritional cost for algal growth. Present research work was planned to minimize nutritional requirements of algae by using food industry waste water as a medium for algal growth towards economical biodiesel production. For this purpose four algal strains (A1, A2, A3 and A4) collected from different fresh water sources were evaluated for their potential use in biodiesel production. The waste water was pre-analyzed to determine the concentrations of different nutrients. All algal strains were grown in Bristol media and different dilutions (10, 20, 40, 80 and 100%) of food industry waste water. Growth data was recorded for one week. The results showed that algal biomass gradually decreased with increasing dilution of food industry waste water and was found higher in 100% waste water concentration than other dilutions. Cultivated algae were harvested for biodiesel production with n-Hexane as oil extractant and NaOH as a catalyst in different combinations through a chemical process ca\led transesterification. The FFA (free fatty acid) profile of algae 1 (A1) by using 75% hexane and 0.5% NaOH combination was found to be higher than other combinations. Higher concentration of NaOH (1%) resulted in soap formation. The aforesaid situations, plus owing to the best biomass production using 100% waste water concentration, deemed algae 1 (A1) as the best candidate among all four strains evaluated for biodiesel production.
Показать больше [+] Меньше [-]Interlinkage between water-energy-food for oil palm cultivation in Thailand Полный текст
2020
Jaroenkietkajorn, Ukrit | Gheewala, Shabbir H.
Biofuels for use in on-road transportation have been promoted in Thailand over the past decade to reduce dependence on imported fossil resources as well as possibly reducing greenhouse gas emissions. This has led to an increase in production of biodiesel which is produced from palm oil. However, as palm oil is also used for food, it is important to take this into consideration as well. Also, oil palm cultivation is rather water-intensive. Hence, it is necessary to analyze the interlinkage between water, food, and energy to have a holistic understanding and prevent trade-offs when addressing one issue in isolation. The water-energy-food nexus for oil palm cultivation in Thailand has been conducted following two widely used methods, the Water-Food-Energy Nexus (WFEN) and Water-Energy-Food (WEF) nexus assessment method. The results are demonstrated as a single score, which is easier for suggesting a suitable area for oil palm plantation. The assessment indicates the southern region of Thailand is the most suitable for oil palm plantation. The recommendation is consistent with the suggestion of the government, based on land and climate suitability. However, this study considers more comprehensive aspects including various other environmental aspects. Oil palm cultivation mainly relates to the amount of freshwater consumption, leading to the increment of fuel consumption for pumping water. On the other hand, the effectiveness of fresh fruit bunch yield (for food and energy production) should be developed in the future. Besides, the results recommend the central region for the expansion of oil palm cultivation in the future because of the availability of a good irrigation infrastructure.
Показать больше [+] Меньше [-]Trade-offs and synergies in the water-energy-food nexus: The case of Saskatchewan, Canada Полный текст
2021
Wu, Linuo | Elshorbagy, Amin | Pande, Saket | Zhuo, La
Socioeconomic and climatic changes and limited water resources pose various challenges to water, energy, and food sectors across the globe. The inevitable interactions between water, energy, and food systems bring about trade-offs but also synergies under different decisions and policies. To gain insights into these issues, we developed a water-energy-food (WEF) nexus model that incorporates both production (supply) and demands sides of WEF systems into a single system-of-systems model using the system dynamics (SD) approach. The model is applied to Saskatchewan, Canada, and so is named WEF-Sask. The model results reveal the various levels of sensitivities of water, energy, and food (and feed) sectors to the socioeconomic and climatic drivers. The analysis of trade-offs and synergies shows that the proposed large irrigation expansion (400%) boosts food production by 1.6% while reducing hydropower production by 2.7% in Saskatchewan. Wind energy expansion strategy (from 5% to 30% of total capacity) makes synergies that not only contribute to electricity supply but also reduce greenhouse gas emissions, industrial water demand, and groundwater use by 2.0, 5.7, and 3.8%, respectively. Biofuel use (blending mandate: 10% ethanol and 5% biodiesel) in transportation cuts GHG emissions by 1.2% but reduces the potential food export (food surplus) by 5.0%. The WEF-Sask model allows for scenario analysis toward integrated resources management, and its generic model structure can be expanded to other regions.
Показать больше [+] Меньше [-]Biodiesel sustainability: The global impact of potential biodiesel production on the energy–water–food (EWF) nexus Полный текст
2021
Chong, Cheng Tung | Loe, Ting Yu | Wong, Kang Yao | Ashokkumar, Veeramuthu | Lam, Su Shiung | Chong, Wen Tong | Borrion, Aiduan | Tian, Bo | Ng, Jo-Han
A data-driven model is used to analyse the global effects of biodiesel on the energy–water–food (EWF) nexus, and to understand the complex environmental correlation. Several criteria to measure the sustainability of biodiesel and four main limiting factors for biodiesel production are discussed in this paper. The limiting factors includes water stress, food stress, feedstock quantity and crude oil price. The 155-country model covers crude oil prices ranging from USD10/bbl to USD160/bbl, biodiesel refinery costs ranging from -USD0.30/L to USD0.30/L and 45 multi-generation biodiesel feedstocks. The model is capable of ascertaining changes arising from biodiesel adoption in terms of light-duty diesel engine emissions (NO, CO, UHC and smoke opacity), water stress index (WSI), dietary energy supply (DES), Herfindahl–Hirschman index (HHI) and short-term energy security. With the addition of potential biodiesel production, the renewable energy sector of global primary energy profile can increase by 0.43%, with maximum increment up to 10.97% for Malaysia. At current crude oil price of USD75/bbl and refinery cost of USD0.1/L, only Benin, Ireland and Togo can produce biodiesel profitably. The model also shows that water requirement varies non-linearly with multi-feedstock biodiesel production as blending ratio increases. Out of the 155 countries, biodiesel production is limited by feedstock quantity for 82 countries, 47 are limited by crude oil price, 20 by water stress and 6 by food stress. The results provide insights for governments to set up environmental policy guidelines, in implementing biodiesel technology as a cleaner alternative to diesel.
Показать больше [+] Меньше [-]Growing biofuel demand in Thailand and Malaysia: water use and impacts. Project report submitted to Food and Agriculture Organization (FAO) under the project, "Comparative assessment of water usage and impacts arising from biofuel projects in SOUTHEAST ASIAn Countries? Полный текст
2014
wannipa soda | upali a. amarasinghe | nishadi eriyagama
Report submitted to Food and Agriculture Organization (FAO) under the project, "Comparative assessment of water usage and impacts arising from biofuel projects in SOUTHEAST ASIAn Countries?, commissioned by the Letter of Agreement No LOA/RAP/2009/38. Thailand and Malaysia are two SOUTHEAST ASIAn countries with rapidly growing biofuel demand. Increasing use of biofuel envisages reducing dependence of petroleum products for transport and mitigating environmental impacts by reducing carbon emissions. It also expects to contribute to rural development and poverty reduction. However, the impacts of expanding production of feedstock for biofuel on water supply are not well understood. This paper assesses the water footprints and impacts of sugarcane molasses and cassava based bioethanol in Thailand, and palm oil based biodiesel in Malaysia. The water footprint of a commodity or service is the water depleted in its life cycle of its production or consumption. The total water footprints of sugarcane molasses and cassava bioethanol production in Thailand are estimated to be 1,646 and 2,304 m3/tonne, respectively, and of palm oil biodiesel in Malaysia is 3,730 m3/tonne. However, the contributions from irrigation are only a small fraction --9.0, 0.7 and 0.3%-- of the total water footprints of molasses and cassava bioethanol, and palm oil biodiesel respectively. In terms of irrigation water use,cassava is a better feedstock for bioethanol production than sugarcane molasses. In Thailand, the total annual irrigation water footprints in bioethanol production --54 million m3 (mcm) for molasses and 15 mcm for cassava-- is only 0.02% of the total renewable water resources. In Malaysia, total annual irrigation water footprint of palm oil biodiesel production is only 0.001% of the total renewable water resources. A significant spatial variation of irrigation water footprints of molasses based ethanol exists across provinces in Thailand, indicating potential for reducing water footprints. The total irrigation water footprints in biofuel production in the future in both countries will also be negligible in comparison to total water availability. However, the impact of wastewater generated in the production processes can have significant impacts on quality of local water resources. A part of the waste water, called 'spent wash', is applied as fertilizer, and over use of it can affect soil and neighboring water resources. The proposed plans on biofuel production in the future can generate more 'spent wash' than that can be used in crop fields as fertilizer. Spent wash has found to have high PH value, temperature, biological and chemical oxygen contents etc. The usual practice of storing spent wash in a pond for a long period near a plant can have detrimental impact on soil, streams' and groundwater quality. In sum, this study concludes that from the perspective of quantity of irrigation water use, the increasing biofuel production does not pose a major problem in Thailand or in Malaysia, and cassava is a better feedstock than sugarcane molasses for bioethanol production. However, the quality of water resources with increasing effluents generated by the biofuel plants could be a major environmental bottleneck to guard against | Upali A. Amarasinghe, Nishadi Eriyagama, Wannipa Soda, 'Growing biofuel demand in Thailand and Malaysia: water use and impacts. Project report submitted to Food and Agriculture Organization (FAO) under the project, "Comparative assessment of water usage and impacts arising from biofuel projects in SOUTHEAST ASIAn Countries?', International Water Management Institute (IWMI), 2014
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