Publications

1- Mohammad I. Abdel-Hamid. "Researches on freshwater microalgae as renewable feedstock of biodiesel industry". Algae Biofuel Summit 2008, 17-19 September, 2008, Delhi, India.

 

Abstract:

Algae are the most efficient biological transformers of light energy to chemical energy through photosynthesis. The chemical energy is stored in a variety of organic molecules including oils and carbohydrates which are the feedstock of biodiesel and bioethanol industries. Microalgae maintain incredibly high production levels of fixed oils compared to oily seed crops. This was the driving force of the current immense international concern considering algae the magic solution for the expected fuel crisis.

Since December 2006, the Company PetrOtech-ffn, Egypt has established a Research and Development Center in Mansoura City, Egypt. The strategic mission of the R&D Centre is to targeting microalgae through intensive and well planned scientific researches to reveal their reliance of being feedstock for commercial production of biofuels; mainly biodiesel and bioethanol. To fulfill this mission, intensive efforts were devoted to isolate microalgae from different habitats including soil, freshwater, brackish water, and hyper saline salt ponds. The outcome was satisfactory, as 75 different algal species and varieties were isolated, so far. Algal isolates were kept as unialgal cultures, many of them are axenic. Most of the isolated algae are chlorophytes, many are cyanobacteria, and some are diatoms. All algal isolates were subjected to pertinent laboratory investigations to define the optimum growth conditions, calculate growth rates, qualitative and quantitative analyses of principal and accessory photosynthetic pigments, lipid content, total carbohydrates, crude proteins, moisture content, ash-free dry weight, ash content, in addition to K, Na, Ca, and P contents. Particular attention was given to algal isolates with relatively higher levels of energy yield. Energy yield is the product of energy content and specific growth rate. The energy content was roughly considered as the sum of lipid content (ether extract), total carbohydrates, and crude proteins, all estimated as % of air-dried algal biomass. Special attention was given to algal isolates with lipid yield of 5% or more. In this case lipids were extracted with n-hexane to simulate the commercial solvent extraction of fixed oils. The extracted lipid fraction was subjected to certain physical and chemical analyses including, but not limited to, determination of specific gravity, acid value, free fatty acids, saponification value, iodine value, qualitative, and quantitative determination of lipid ingredients using GC/MS analysis. These analyses are of prime importance to assess the suitability of algal lipids for biodiesel industry. Algal isolates having reasonable production of crude lipids suitable for biodiesel production, maintaining relatively higher growth rates, accommodating wide fluctuations in growth controlling environmental factors, exhibiting outstanding competitive performance in mass culture, and able to grow abundantly in naturally fertile  effluents including treated domestic sewage and agricultural runoff, were selected for laboratory and outdoor trials of mass production. The massive production of algal biomass is the backbone of economic and feasible production of biofuels from algae. Based on these criteria, only six algal species were selected; four belong to the green chlorococcalian genera, Monoraphidium, Chlorella, and Scenedesmus and two species belong to the pinnate diatom Nitzschia. Three models of open ponds were designed for scaling up and optimizing the process of mass production. The open ponds include a bench top model, field incubating and seeding pond, and  large raceway open pond with surface areas of 0.2 m2, 10 m2, and 1000 m2, respectively. Specially designed photobioreactors were used to raise some microalgae with incredible yield of hydrocarbon biofuel (30% to 55% of dry biomass) but require specific and well controlled growth conditions including light regime, temperature and composition of the nutrient medium. Intensive scientific researches are currently performed to produce biodiesel and bioethanol form microalgae.