| Mariculture organic waste mainly consists of bait which is not absorbed by fishand fish waste. These organic compounds contain large amounts of N, P and otherelements as well as cellulose, polysaccharide, protein and other macromolecularcompounds, is a valuable and available raw material resources. If we can effectivelyuse these organic matters, waste can be disposed properly and environment isprotected well at the same time. Since twenty-first Century, one of the most seriouscrises that human face is the shortage of energy, seeking and developing renewable,green energy as a substitute for oil crunch time. In all the alternative energy, hydrogenis a high heat value, no pollution and clean energy. At present, most research methodsof hydrogen product are anaerobic fermentation method, access to energy in thedegradation of organic pollutants. Fermentation from mariculture organic waste hasbroad development space and application prospect, but the technology is still in thestage of laboratory research, various influence factors and mechanism are not veryclear. Especially the mariculture organic wastes contain amounts of inorganic salt,which form certain salinity, the effect of anaerobic fermentation hydrogen productionfrom mariculture organic wastes remains further research. This paper investigatesthree aspects of mariculture organic waste on hydrogen production. First of all,mariculture organic waste is not easy to be directly used by hydrogen-producingbacteria, hydrolysis of this waste is needed to degrade large molecules into smallmolecules, such as glucose, amino acid etc. The second study is the effect of differentsubstrate concentrations conditions on hydrogen production. Finally, the effect ofsalinity on produce hydrogen from mariculture organic waste is investigated. Hydrolysis of mariculture organic waste using treatment methods is investigated.The results show that the best method is compound enzymatic treatment, the releasingof SCOD, carbohydrate and protein are enhanced by1.3,0.9,1.3folds respectively.The optimum processing time is6~8h. Acid and alkali methods are not effective forthe releasing of carbohydrate, but more effective for the releasing of SCOD andprotein than enzymatic treatment. The optimum processing time was8~12h. S-TEmethod can hydrolyze organic waste rapidly, but the optimum time for releasing ofSCOD and protein is10h. The effect of hydrolysis on high concentrations ofmariculture waste using enzymatic treatment is more effective than that on lowconcentrations, it also needs more time.Hydrogen production characteristics of different concentrations of maricultureorganic waste are investigated. The results show that, the hydrogen proportion is thehighest (82.1%) while the concentration is20g/L; and the highest cumulativehydrogen production is45.4mL/mg VSS while the concentration is5g/L. Thereleasing of soluble protein is far greater than utilizing. SCOD fluctuates: firstdecrease and then increase; at the end of the fermentation SCOD is still high. The pHdecrease gradually, pH is6.2~6.6at the fastest stage of hydrogen production.Fermentation products are mainly acetic and ethanol, it belongs to ethanol typefermentation.Effect of hydrogen production on different salinity of mariculture organic wasteis investigated. The results show that, there is no influence on total amount offermentation gas with the increase of salinity, but hydrogen ratio is reduced. Thereleasing of carbohydrates is promoted in a certain range of salinity, but there is noeffect more than3.0%salinity. The increase in salinity can inhibit the production ofpropionic and butyric, and fermentation type of mixed acid converts to aceticfermentation. |
PDF Full Text Request