Effects of Electromagnetic Hydrolysis on Algal Concentration in Warm, Stagnant Surface Water

Background:: The study was conducted in-situ at the INCA Pond system in the City of Boynton Beach, Florida which has experienced issues with the formation of harmful algae blooms that create nuisance complaints and unhealthy conditions in the water and surrounding area. Objective:: The EMOH device is designed to supersaturate water as a means to deter harmful algal blooms. This pilot study was conducted to determine if an Electromagnetic Hydrolysis (EMOH) device can improve the health of residential surface water by adding dissolved oxygen to the water to allow the existing bacteria to remove the substrate that provides a food source for blue-green algae outbreaks when combined with naturally occurring aerobic bacteria. Methods:: Combining the EMOH device with naturally occurring aerobic bacteria demonstrated that a pond that normally contained a low DO and copious amounts of algae, would contain fewer algal blooms, that the bacteria would consume the detrital layer on the bottom of the pond that acts as nutrient source for the algae and that DO levels increase with temperature, in contrast to expectations. Four configurations were compared. Results: : The EMOH device successfully reduced the detrital layer on the bottom of the pond and experienced fewer algal blooms. The use of surface aeration permits the oxygen to escape, so having the EMOH discharge below the surface increases efficiency. Conclusion:: The EMOH device successfully accomplished its intended goals.

Estimate of void fraction and air entrainment flux in hydraulic jump using Froude number

Hydraulic jumps are induced in hydraulic facilities for the purposes of energy dissipation or flow aeration. Presently there is no means for a simple estimate of void fraction distribution and air entrainment flux, without detailed physical modelling. This paper presents a semi-theoretical model to simulate the void fraction and velocity distributions in hydraulic jumps characterized by partially-developed inflow conditions. Relationships were established between the inflow Froude number, jump roller length and key parameters that determine the full expression of void fraction and velocity profiles. The proposed model enables accurate prediction of void fraction, longitudinal velocity, and air flux using the inflow Froude number. The results indicated considerable air flux contribution of free-surface aeration, in addition to the singular air entrainment at the jump toe, for moderate to large Froude numbers. A Froude number between 8 and 9 tended to achieve highest aeration rate with maximum total air flux in the roller.

Solid-State Fermentation of Banana Peels Potential Study for Feed Additive

Agricultural solid wastes present abundantly on earth as crops harvesting as well as processing are countinuesly run. Banana peels are one of agricultural solid wastes produced anywhere the banana processing presents. The peels present abundantly in tropical countries such as Indonesia. The carbohydrate content of banana peels make it useful for the production of many chemicals, including feed. Meanwhile the large need in feed in farming including fish farming could prevent farmer to obtain substantial profit. This research studied the possibility of banana peel as one of abundant Indonesian agricultural solid waste to be utilized as fish feed which is known requiring certain level of protein content. This was done by fermenting the peels in fixed bed reaction mode using surface aeration and non-aeration. The fermentation was conducted using yeast Saccharomyces cerevisiae Y1536 and Rhizopus Oryzae FNCC 6157. The reaction time was varied for 1, 3, and 5 days. The important parameters studied were protein contents, and amylase activity of the fermented banana peels. Despite aeration indicated more operational cost, it showed significant impact on the fermentation of banana peels. The best condition for fermentation using Saccharomyces cerevisiae Y1536 were 5 day fermentation with surface aeration which result in the increase of protein content up to 4.05%, the decrease of fiber content up to 1.08%, and amylase activity of 9.99 DP. Whilst the fermentation using Rhizopus Oryzae FNCC 6157 obtained its best result at 1 day fermentation with aeration, which are protein content increase up to 4.04% and fiber content decrease up to 0.69%. However, the fermentation using this mold showed its best amylase activity result of 12.75 DP at 5 day surface aerated fermentation.

Turbulence in continuous flow surface aeration systems

Turbulence characteristics in an optimal continuous surface aeration system were investigated in this study. The experimental system consists of a rectangular tank, where flow is driven by equally spaced aerators placed on the liquid surface. The mass-transfer coefficient and turbulent parameters at the tank's inlet and outlet were measured to enable analysis of their interdependent relationships. The turbulence parameters are linked closely to the system's mass-transfer process. Turbulent bursting analysis has shown that ejection and sweep events govern the hydrodynamics of the systems. Turbulent intensity increases with increasing speed of rotation, and consequently the mass-transfer coefficient also increases. The universal probability distribution functions of the velocity fluctuations in continuous flow surface aeration systems follow the Gram-Charlier series, based on exponential distribution, and the theoretical and experimental curves match.