Chemical Engineering Department, Universiti Teknologi PETRONAS, 32610 Seri Iskandar, Perak, Malaysia; Centre for Biofuel and Biochemical Research, Institute of Self-Sustainable Building, Universiti Teknologi PETRONAS, 32610 Seri Iskandar, Perak, Malaysia.
Chemical Engineering Department, Universiti Teknologi PETRONAS, 32610 Seri Iskandar, Perak, Malaysia; Centre for Biofuel and Biochemical Research, Institute of Self-Sustainable Building, Universiti Teknologi PETRONAS, 32610 Seri Iskandar, Perak, Malaysia.
Sci Total Environ. 2019 Oct 20;688:112-128. doi: 10.1016/j.scitotenv.2019.06.181. Epub 2019 Jun 14.
The rapid depletion of fossil fuels and ever-increasing environmental pollution have forced humankind to look for a renewable energy source. Microalgae, a renewable biomass source, has been proposed as a promising feedstock to generate biofuels due to their fast growth rate with high lipid content. However, literatures have indicated that sustainable production of microalgae biofuels are only viable with a highly optimized production system. In the present study, a cradle-to-gate approach was used to provide expedient insights on the effect of different cultivation systems and biomass productivity toward life cycle energy (LCEA), carbon balance (LCCO) and economic (LCC) of microalgae biodiesel production pathways. In addition, a co-production of bioethanol from microalgae residue was proposed in order to improve the economic sustainability of the overall system. The results attained in the present work indicated that traditional microalgae biofuels processing pathways resulted to several shortcomings, such as dehydration and lipid extraction of microalgae biomass required high energy input and contributed nearly 21 to 30% and 39 to 57% of the total energy requirement, respectively. Besides, the microalgae biofuels production system also required a high capital investment, which accounted for 47 to 86% of total production costs that subsequently resulted to poor techno-economic performances. Moreover, current analysis of environmental aspects of microalgae biorefinery had revealed negative CO balance in producing microalgae biofuels.
化石燃料的迅速枯竭和日益严重的环境污染迫使人类寻找可再生能源。微藻作为可再生生物质资源，由于其生长速度快、脂质含量高，被认为是生产生物燃料的有前途的原料。然而，文献表明，只有通过高度优化的生产系统，才能实现可持续生产微藻生物燃料。在本研究中，采用摇篮到大门的方法，快速了解不同培养系统和生物质生产力对微藻生物柴油生产途径的生命周期能源（LCEA）、碳平衡（LCCO）和经济（LCC）的影响。此外，还提出了从微藻残渣中联产生物乙醇，以提高整个系统的经济可持续性。本工作的结果表明，传统的微藻生物燃料加工途径存在一些缺点，例如微藻生物质的脱水和脂质提取需要高能量输入，分别占总能源需求的近 21%至 30%和 39%至 57%。此外，微藻生物燃料生产系统还需要大量的资本投资，占总生产成本的 47%至 86%，从而导致技术经济性能不佳。此外，目前对微藻生物炼制厂环境方面的分析表明，生产微藻生物燃料存在负的 CO 平衡。
