Production of lipids for bioconversion to biodiesel using new sludge isolated microorganisms and employing wastewater sludge as a raw material

废水污泥产生量大，其在环境中的安全处置是一个世界性的问题。我们研究的长期目标是利用污泥作为原料生产增值产品。由于原油供应的减少、石油价格的不稳定、减少温室气体排放的必要性以及政府制定措施规定生物燃料在运输中的最低比例，对脂肪酸甲酯（FAME）作为生物柴油的需求显著增加。因此，本研究的主要目的是开发一种经济的工艺，以废水污泥为原料生产生物柴油。事实上，我们已经分离出了新的异养产油菌株，它们积累的脂质高达细胞干重的60%，并在污泥中增殖。根据我们的计算，我们发现，从污泥生产生物柴油的输出/输入的能量比为5.1，并大大减少了绿色气体。因此，本研究项目的具体目标是：鉴定新菌株，优化油脂生产工艺参数（pH值，C：N比，污泥固体浓度，进料策略，温度）;污泥水解以增加产油菌株的生长和油脂积累;建立放大标准并研究从发酵污泥生物质中提取油脂并将油脂转化为生物柴油。研究的成功完成：1）将提供一种经济的生物柴油生产新工艺; 2）减少60 - 70%w/w的污泥处理量，从而最大限度地降低处理成本; 4）通过生物柴油替代石油柴油，最大限度地减少绿色家用气体的产生。此外，这项研究是非常及时的，将有助于加拿大工业发展生态友好和商业上可行的生物柴油加强加拿大的环境政策。3名博士、1名PDF和1名研究助理将接受这一新课题的培训。

Wastewater sludge is produced in large quantityand its safe disposal in the environment is a world wide problem. The long term goal of our research is to produce value added products using sludge as a raw material. Demand for fattyacid methyl esters (FAMEs) as biodiesel has increased significantlydue to the depleting crude oil supplies, instabilityof petroleum prices, necessityto reduce GHG and the development of government measures to establish a minimum proportion of biofuel in transport. Therefore, the principal objective of the present research is to develop an economical process for biodiesel production using wastewatersludge as raw material. In fact, we have isolated new heterotrophic oleaginous strains which accumulate lipids up to 60% of cell dryweight and proliferate in sludge. Based on our calculation we find that biodiesel production from sludge has an output/input energyratio of 5.1 and substantiallyreduced green house gases. Therefore, the specific objectives of the present research project are: identification of new strains, optimize the process parameters for lipid production (pH, C:N ratio, sludge solids concentration, feeding strategy, temperature); sludge hydrolysis to increase growth & lipids accumulation byoleaginous strains; to establish scale-up criteria and to studythe extraction of lipids from fermented sludge biomass and conversion of lipids tobiodiesel. The successful completion of the research: 1) will provide a new process for economical biodiesel production; 2) reduce the sludge volume by60-70 % w/w for disposal and hence minimize disposal cost; and 4) minimize production of green house gases through replacement of petroleum diesel bybiodiesel. Furthermore, this research is verytimelyand will aid Canadian industryto develop eco-friendlyand commerciallyviable biodiesel strengthening Canada`s environmental policy. 3 PhD, 1 PDF and a research assistant will be trained on this new subject.