Integrated Biorefinery Approach towards production of sustainable fuel and chemicals from Algal biobased systems

Energy is the next burning issue in the upcoming year when every country requires a huge amount to sustain its economical progress. Continued use of petroleum-sourced fuels is widely recognized as unsustainable because of depleting supplies and their contribution to the accumulation of Green House Gases (GHG) such as CO2 in the environment, which induced potential Global Warming. Mitigation strategies have therefore become a focus of intensive research, and the principal goal of International Environmental Policy.

In a wider context, there are three main drivers for the promotion, development and implementation of biofuels. In principle, these are energy independence, climate change and rural development. The main theoretical reasons for the promotion of biofuels can be summarised as follows:

i) Biofuels can improve independence and energy security: Local, national or global production of energy can avoid the reliance on politically and/or socially unstable energy suppliers. In addition, the global oil demand is increasing exponentially and there is a need to find alternatives to fossil fuels derived from petroleum.

ii) Biofuels may contribute to a reduction in carbon emissions: Biofuels have been often considered a solution to climate change. In fact, net emissions from biofuels have      been reported to be remarkably lower than those generated from the combustion of fossil fuels.

iii) Biofuels can help to increase farm income and contribute to rural development: With a growing biofuels market, many countries will be able to grow more types of crops to cover national or foreign demands on energy crops. The increasing demand for agriculture due to the labor-intensive plant derived technologies is expected to improve farm income.

Biofuels and the energy sector are the component of the newly emerging knowledge based bio-economy. Society is only now beginning to recognise the opportunities offered by such a bio-economy and is starting to develop the technologies required. It is now increasingly recognised globally that plant based raw materials will eventually replace fossil reserves as feedstocks for industrial production addressing both the energy and non-energy sectors include chemicals and materials. Such an integrated approach is necessary, which recognises and supports the variety of uses of plant material to realise the full range of potential benefits to society (The Royal Society, 2008).

Industries such as chemical, food, feed, material and fuel industries are seeking sustainable biomass feedstocks. Microalgae is among the most promising ones, but innovation and industry collaboration efforts are needed to develop it into a commercial activity for bulk products. Therefore, algal biomass and other lignocellulosic aquatic biomass (e.g. water hyacinth, Pistea, etc.) as feedstock can offer the potential to provide novel solutions for the production of biofuels/chemicals. Recently biorefinery concept has received a lot of attention as they are capable of providing a variety of products of various industrial applications from different feed stocks. Biorefinery includes the selective isolation of products (proteins, carbohydrates, lipids) from crude biomass (see the above Figure). This process needs to proceed in a carefully and efficient manner, in order to maintain the functionality of the products (e.g. native protein conformation) constituting their value. The co-production of multiple products from microalgae is a new challenge. This project seeks to assemble and integrate corporate interests with ongoing research efforts to utilize all the potential products available from microalgae in a sustainable manner. We will create and assess a new value-chain around the microalgae feedstocks. Through innovation and industry collaboration we will assemble a model for a sustainable biorefinery with the potential to initiate a demonstration project.

The choice of biomass feedstock ultimately depend on crops yields, regional conditions, food coproduction, economics and the life cycle thermal efficiency (LCTE). Biomass, which is typically in a low density form, must be collected and transported to a central processing facility so that it can be converted into transportation fuel. The edible and     non-edible part of biomass can be separated and the non-edible fraction can then be converted into a fuel. The nutrients from the biomass also can be separated and reused for further biomass growth            

The potential benefits of microalgae cultivation are enormous, and research into algae production using wastewater and power station emissions are inviting a highly prioritize proposition in sustainable and economic development. While microalgae based biodiesel has been found to be sustainable and promising alternative to fossil fuel, the lack of available raw material of suitable lipid producer strain(s) and cost effective cultivation system continues to be the major challenges for large scale commercial production of biofuels. The key bottleneck towards considering microalgal strain as green cell factory for such production is the mutually exclusive nature of their growth, biomass and lipid productivity which results in reduction of net energy gain. Therefore, it would be ideal that a true producer strain would exhibit optimum biomass and lipid productivity along with robust growth under transient change in growth conditions under open or closed cultivation system. In this respect, the proposed research is highly relevant and addresses the problems that hinder large scale production of biofuels. The expected outcome of this endeavor is believed to be integration of cost-effective mass cultivation system with microalgal strain(s) capable of robust growth and biomass production under selective mass cultivation system utilizing industrial wastes (CO2 and waste saline water) as well as production of lipid at desired quantities to enable upgraded downstream processing of resultant biomass towards biofuel production. Apart from that efforts will be made to develop an integrated process for complete utilization of lignocelluloses and aquatic waste biomass for the production of biofuels and value added chemicals by using supercritical CO2 technology and hydrodynamic cavitations technology.

Impact on sustainable Industrial development

In recent times many sectors are working towards development of microalgae mass cultivation system for various biotechnological applications such as biofuel and other high valued co-products development. The final outcome of the proposed project will be a set of ready to use producer strains for biodiesel and high valued co-products production. To that end, the outcome will be one step ahead towards scale up operation. Further, an unbiased and rational designing of cost effective mass cultivation technique of the selected strain(s) will be the principal output of the project. Moreover the integration of microalgae mass cultivation strategy for reduction of industrial CO2 emission may be directly benefitted the sustainability of the proposed outcome of the project. Future research towards developing microalgae mass cultivation will be able to directly use our design strategy in regional development.

Impact on Social and National energy and Environmental security

Successful implementation of the proposed project may directly or indirectly contribute to the achievement of national energy security, eradication of extreme poverty and environmental sustainability. From a social perspective, the major impact of the project will be through generation of employments through large scale commercial cultivation of microalgae based biofuel production that will involve participation and ownership of manpower required at various stages of operations, e.g cultivation, harvesting, drying and processing of oil to fuels and other co-products. The proposed project foresees the sustainable production of renewable fuels using indigenous microalgae resources with auspicious industrial collaboration.