Millions of pounds of readily usable and renewable byproduct are discarded yearly from the rapidly expanding Louisiana crawfish processing industry. This investigation involved utilization of crawfish waste shell to produce the biopolymers chitin and chitosan, and to utilize chitosan as a coagulant and in ligandexchange column technology for recovery of organic compounds from seafood processing discharge stickwater. Crawfish shell was found to be an excellent source of chitin (23.49% on a dry basis) and applicable physicochemical procedures for isolation of chitin from crawfish shell and its conversion to chitosan were developed. Particular attention was given to characterization of the physicochemical properties of crawfish waste and its chitinous biopolymers. Crawfish chitosan coagulated suspended solids in stickwater obtained from the crawfish pigment extraction process as effectively, or greater, than seven commercial polymers and four inorganic salts under the test conditions. Concentration of suspended solids and turbidity were reduced 97% and 83%, respectively, by treatment with 150 mg/L chitosan at pH 6.0, with a 45% reduction in chemical oxygen demand (COD). Proximate and amino acid

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Application of Crawfish Chitosan as a Coagulant in Recovery of Organic Compounds From Seafood Processing Wastes.

Some of Thai traditional fermented fishery products were found to be a source of angiotensin I-converting enzyme (ACE) inhibitory and antioxidative peptides which could be used for the hypertension control. The highest ACE inhibitory activity was found in the extract from Pla-som. For antioxidative activities, the extracts from Bu-du, Kung-chom and Kem-buk-nud exhibited the highest 2,2-diphenyl-1-picryl hydrazyl (DPPH) radical scavenging activity, 2,2-azino-bis (3-ethylbenzothiazoline-6sulfonic acid) (ABTS) radical scavenging activity and ferric reducing antioxidant power (FRAP) (p<0.05), respectively. Based on principal component analysis (PCA), peptides with high ACE inhibitory activity were more likely present in products with low pH and low salt content. The presence of these peptides was probably governed by the use of garlic and raw material used but not affected by the ratio of free and total free α -amino acids (F/T ratio). For antioxidative activities, peptides with high FRAP were more likely found in products with high F/T ratio. Products with high DPPH radical scavenging activity more likely had high ABTS radical scavenging activity but both activities showed no correlation to pH, salt content and F/T ratio. In addition, ACE inhibitory activity exhibited no correlation to antioxidative activities. Since ACE inhibition is the main effect on blood pressure lowering, Pla-som produced from Puntius gonionotus which showed the highest ACE inhibitory activity was further studied. Inoculation of Pediococcus acidilactici BCC 9545 and Staphylococcus xylosus BCC3710 in Pla-som produced from Puntius gonionotus resulted in a reduction of fermentation time but could not increase the release of ACE inhibitory

https://kb.psu.ac.th/psukb/bitstream/2010/8816/1/345014.pdf

Study on angiotensin I-Converting enzyme inhibitory activity and antioxidative activity of peptides derived from some Thai traditional fermented fishery products

Limitations of the fission fuel resources will presumably mandate the replacement of thermal fission reactors by fast fission reactors that operate on a self-sufficient closed fuel cycle. This replacement might take place within the next one hundred years, so the direct competitors of fusion reactors will be fission reactors of the latter rather than the former type. Also, fast fission reactors, in contrast to thermal fission reactors, have the potential for transmuting long-lived actinides into short-lived fission products. The associated reduction of the long-term activation of radioactive waste due to actinides makes the comparison of radioactive waste from fast fission reactors to that from fusion reactors more rewarding than the comparison of radioactive waste from thermal fission reactors to that from fusion reactors. Radioactive waste from an experimental and a commercial fast fission reactor and an experimental and a commercial fusion reactor has been characterized. The fast fission reactors chosen for this study were the Experimental Breeder Reactor 2 and the Integral Fast Reactor. The fusion reactors chosen for this study were the International Thermonuclear Experimental Reactor and a Reduced Activation Ferrite Helium Tokamak. The comparison of radioactive waste parameters shows that radioactive waste from the experimental fast fission reactormore » may be less hazardous than that from the experimental fusion reactor. Inclusion of the actinides would reverse this conclusion only in the long-term. Radioactive waste from the commercial fusion reactor may always be less hazardous than that from the commercial fast fission reactor, irrespective of the inclusion or exclusion of the actinides. The fusion waste would even be far less hazardous, if advanced structural materials, like silicon carbide or vanadium alloy, were employed.« less

/pdf/a-comparison-of-radioactive-waste-from-first-generation-2s95r1nqf8.pdf

A comparison of radioactive waste from first generation fusion reactors and fast fission reactors with actinide recycling

This report surveys waste production rates and disposal practices at EBR-II, a small-scale liquid-metal fast breeder reactor, for the past decade. Normal airborne wastes have been reduced by switching to low-sulfur fuel oil in auxiliary boilers and converting to use of reactor steam for part of the plant space heating. Atmospheric releases of gaseous radioactive wastes initially increased during the implementation of program for testing reactor fuels to and beyond cladding breach; but the effluent rates have now been reduced to far below permissible limits by use of a cryogenic distillation column. EBR-II's small production of liquid radioactive waste is handled by evaporation, followed by disposal of the evaporator sludge as solid waste. Liquid-waste releases meet all applicable state and federal standards. Solid wastes are sent to two storage/disposal areas- one of which is reserved primarily for storage of materials containing sodium, pending development of a facility for disposal of the sodium.

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L. C. Witbeck

Papers

Waste Production and Management at EBR-II