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Among the three types of technologies available in the fisheries sector in India, seaweed farming, initially promoted as a livelihood option, has emerged as the one area which probably has the maximum potential for up-scaling. This paper has examined the structure, conduct and performance of the value chain in seaweed farming in India inquiring into the production, institutional, marketing, social and community relationships in small-scale seaweed farming in the Ramanathapuram district of Tamil Nadu and the concept of self-help groups (SHG) as an increasingly workable option for coastal resources management. The value chain analysis of the sector has substantially proved that committed and synergistic production, marketing and institutional arrangements enabled by corporate leadership, offers considerable savings in transaction costs. The SHG model has also shown strong gender orientation in the initial years of seaweed culture in the district contributing to strong structural foundations to the movement. The seaweed sector in the coastal India has all the potential to rise from the low-income conditions normally associated with basic livelihood activities to higher levels of employment-income-consumption relationships.

Studies on the growth and reproductive behaviour of Gracilaria corticata carried out at Mandapam and Pudumadam in the Gulf of Mannar, over a period of three years from 1968 to 1970 have been presented, along with some observations on the distribution and harvest of the crop. The growth of the species appears to be irregular and the peak growth occurs during June to August/September and December to February/March, Seasonal changes have not been observed in the abundance of reproductive plants which occurred throughout the year. Tetrasporic plants have predominant in the populations examined at Mandapam and Pudumadam than the sexual plants. Harvesting experiment conducted at Pudumadam showed that the time of harvest and periodic collection of plants influence the rate of production and density of the alga in the natural habitats and that it is profitable to harvest G. corticata twice in a year, during June to August/September and December to February/March.

Colloidal solutions of silver nanoparticles (AgNPs) were synthesized by gamma Co-60 irradiation using different stabilizers, namely polyvinyl pyrrolidone (PVP), polyvinyl alcohol (PVA), alginate, and sericin. The particle size measured from TEM images was 4.3, 6.1, 7.6, and 10.2 nm for AgNPs/PVP, AgNPs/PVA, AgNPs/alginate, and AgNPs/sericin, respectively. The influence of different stabilizers on the antibacterial activity of AgNPs was investigated. Results showed that AgNPs/alginate exhibited the highest antibacterial activity against Escherichia coli (E. coli) among the as-synthesized AgNPs. Handwash solution has been prepared using Na lauryl sulfate as surfactant, hydroxyethyl cellulose as binder, and 15 mg/L of AgNPs/alginate as antimicrobial agent. The obtained results on the antibacterial test of handwash for the dilution to 3 mg AgNPs/L showed that the antibacterial efficiency against E. coli was of 74.6%, 89.8%, and 99.0% for the contacted time of 1, 3, and 5 min, respectively. Thus, due to the biocompatibility of alginate extracted from seaweed and highly antimicrobial activity of AgNPs synthesized by gamma Co-60 irradiation, AgNPs/alginate is promising to use as an antimicrobial agent in biomedicine, cosmetic, and in other fields.

The Department of Energy’s Bioenergy Technology Office (BETO) collaborates with a wide range of institutions towards the development and deployment of biofuels and bioproducts. To facilitate this effort, BETO and its partner national laboratories develop detailed techno-economic assessments (TEA) of biofuel production technologies as part of the development of design cases and state of technology (SOT) analyses. A design case is a TEA that outlines a target case for a particular biofuel pathway. It enables preliminary identification of data gaps and research and development needs and provides goals and targets against which technology progress is assessed. On the other hand, an SOT analysis assesses progress within and across relevant technology areas based on actual experimental results relative to technical targets and cost goals from design cases and includes technical, economic, and environmental criteria as available.

BETO also develops supply chain sustainability analyses (SCSA) for key biofuel production technologies that are the subject of design case or SOT analyses (Dunn et al. 2013). The SCSA utilizes a life-cycle analysis to estimate the energy use and greenhouse gas (GHG) emissions associated with biofuel production and assists in comparing several biofuel pathways. This report documents an SCSA of whole algae hydrothermal liquefaction (AHTL) as the conversion technology to produce renewable diesel (RD). Jones et al. (2014) developed the design case process model that provides the material and energy intensity of the feedstock conversion step in the SCSA.

The SCSA production stages for microalgae-derived RD are presented in Figure 1. Various inputs (red boxes) can be considered for each supply chain step (green boxes). These inputs can include energy, fertilizers for biomass growth, and any materials that may be needed during the conversion process. The major environmental output from the system is GHG emissions, which come from direct sources like fuel combustion during a processing step or indirect sources like fertilizer production. Another common output is coproducts, which can be used to displace materials or energy from other production processes. There can be difficulties in allocating emissions to these co-products (Wang et al., 2011), so care is needed during their consideration.

The SCSA for RD produced via AHTL starts with feedstock production, which requires nutrients (fertilizers), water (not considered in this study), and energy in the form of electricity and other fuels, e.g., natural gas. After production, the feedstock is transported to the conversion facility, or biorefinery, using energy in the form of a transportation fuel. In the case of microalgae, cultivation ponds are assumed to be co-located with the conversion facility (Davis et al., 2012; Frank et al., 2011) meaning a transportation fuel is not required. However, energy is needed for pumping the biomass from the harvesting units to the biorefinery. For the algae-to-RD production reported here, the harvested feedstock goes to a thermal conversion process, which includes material inputs like catalysts and sulfuric acid. A small amount of naphtha, which was treated as a liquid fuel, is produced along with RD in the AHTL pathway. No other co-products are produced in the fully integrated AHTL algae-to- RD pathway. The total supply chain emissions burdens were allocated to total fuel produced, including naphtha and RD.

The renewable fuel, after the conversion process, is transported to a fueling station by train, barge, and truck. The biogenic CO2 released when the fuel is combusted balance out with the atmospheric CO2 that the algae incorporated when it was growing (Frank et al., 2011). The emissions described above are the so-called, “fuel cycle” emissions. Emissions are also associated with the construction of the plant (Canter et al., 2014). These “infrastructure cycle” emissions were estimated in this study.