Entropy generation minimization (finite time thermodynamics, or thermodynamic optimization) is the method that combines into simple models the most basic concepts of heat transfer, fluid mechanics, and thermodynamics. These simple models are used in the optimization of real (irreversible) devices and processes, subject to finite‐size and finite‐time constraints. The review traces the development and adoption of the method in several sectors of mainstream thermal engineering and science: cryogenics, heat transfer, education, storage systems, solar power plants, nuclear and fossil power plants, and refrigerators. Emphasis is placed on the fundamental and technological importance of the optimization method and its results, the pedagogical merits of the method, and the chronological development of the field.

Entropy generation minimization: The new thermodynamics of finite-size devices and finite-time processes

As the fossil fuels are depleting day by day, there is a need to find out an alternative fuel to fulfill the energy demand of the world. Biodiesel is one of the best available resources that have come to the forefront recently. In this paper, a detailed review has been conducted to highlight different related aspects to biodiesel industry. These aspects include, biodiesel feedstocks, extraction and production methods, properties and qualities of biodiesel, problems and potential solutions of using vegetable oil, advantages and disadvantages of biodiesel, the economical viability and finally the future of biodiesel. The literature reviewed was selective and critical. Highly rated journals in scientific indexes were the preferred choice, although other non-indexed publications, such as Scientific Research and Essays or some internal reports from highly reputed organizations such as International Energy Agency (IEA), Energy Information Administration (EIA) and British Petroleum (BP) have also been cited. Based on the overview presented, it is clear that the search for beneficial biodiesel sources should focus on feedstocks that do not compete with food crops, do not lead to land-clearing and provide greenhouse-gas reductions. These feedstocks include non-edible oils such as Jatropha curcas and Calophyllum inophyllum , and more recently microalgae and genetically engineered plants such as poplar and switchgrass have emerged to be very promising feedstocks for biodiesel production. It has been found that feedstock alone represents more than 75% of the overall biodiesel production cost. Therefore, selecting the best feedstock is vital to ensure low production cost. It has also been found that the continuity in transesterification process is another choice to minimize the production cost. Biodiesel is currently not economically feasible, and more research and technological development are needed. Thus supporting policies are important to promote biodiesel research and make their prices competitive with other conventional sources of energy. Currently, biodiesel can be more effective if used as a complement to other energy sources.

A comprehensive review on biodiesel as an alternative energy resource and its characteristics

http://biodiesel.persiangig.com/Cultivation/(3)Microalgae%20biofuels-%20A%20critical%20review%20of%20issues,%20problems%20and%20the%20way%20forward%20Review%20Article.pdf

Microalgae biofuels: A critical review of issues, problems and the way forward

https://openscholar.dut.ac.za/bitstream/10321/1400/1/rawat__kumar__mutanda___bux_2013_aplplied_energy.pdf

Biodiesel from microalgae: A critical evaluation from laboratory to large scale production

The economically significant production of carbon-neutral biodiesel from microalgae has been hailed as the ultimate alternative to depleting resources of petro-diesel due to its high cellular concentration of lipids, resources and economic sustainability and overall potential advantages over other sources of biofuels. Pertinent questions however need to be answered on the commercial viability of large scale production of biodiesel from microalgae. Vital steps need to be critically analysed at each stage. Isolation of microalgae should be based on the question of whether marine or freshwater microalgae, cultures from collections or indigenous wild types are best suited for large scale production. Furthermore, the determination of initial sampling points play a pivotal role in the determination of strain selection as well as strain viability. The screening process should identify, purify and select lipid producing strains. Are natural strains or stressed strains higher in lipid productivity? The synergistic interactions that occur naturally between algae and other microorganisms cannot be ignored. A lot of literature is available on the downstream processing of microalgae but a few reports are available on the upstream processing of microalgae for biomass and lipid production for biodiesel production. We present in this review an empirical and critical analysis on the potential of translating research findings from laboratory scale trials to full scale application. The move from laboratory to large scale microalgal cultivation requires careful planning. It is imperative to do extensive pre-pilot demonstration trials and formulate a suitable trajectory for possible data extrapolation for large scale experimental designs. The pros and cons of the two widely used methods for growing microalgae by photobioreactors or open raceway ponds are discussed in detail. In addition, current methods for biomass harvesting and lipid extraction are critically evaluated. This would be novel approach to economical biodiesel production from microalgae in the near future. Globally, microalgae are largest biomass producers having higher neutral lipid content outcompeting terrestrial plants for biofuel production. However, the viscosities of microalgal oils are usually higher than that of petroleum diesel.

Biodiesel from microalgae: a critical evaluation from laboratory to large scale production. Appl Energy

Variables affecting the in situ transesterification of microalgae lipids

Anaerobic digestion of microalgae residues resulting from the biodiesel production process

The production of methane (CH 4 ) via the anaerobic digestion of microalgae biomass residues from the biodiesel production process has the potential to meet some of the energy requirements of the primary biomass to fuel conversion process This paper investigates the practical CH 4 yields achievable from the anaerobic conversion of the microalgae residues (as well as codigestion with glycerol) after biodiesel production using both the conventional and in situ transesterification methods Results demonstrate that the type of lipid extraction solvent utilized in the conventional transesterification process could inhibit subsequent CH 4 production On the basis of actual CH 4 production, a recoverable energy of 87-105 MJ kg -1 of dry microalgae biomass residue was obtained using the lipid extracted and transesterified microalgae samples On codigesting the microalgae residues with glycerol, a 4-7% increase in CH 4 production was observed

https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1757-1707.2009.01029.x

Energy recovery from lipid extracted, transesterified and glycerol codigested microalgae biomass

Synthesis of nano-hydroxyapatite (nHA) from waste mussel shells using a rapid microwave method

http://www.physics.otago.ac.nz/research/ice/publications/PetrichLS_CRST.pdf

Zhifa Sun

Papers

Variables affecting the in situ transesterification of microalgae lipids

Anaerobic digestion of microalgae residues resulting from the biodiesel production process

Energy recovery from lipid extracted, transesterified and glycerol codigested microalgae biomass

Synthesis of nano-hydroxyapatite (nHA) from waste mussel shells using a rapid microwave method

Modelling the interrelationships between permeability, effective porosity and total porosity in sea ice