Savremeni pristupi u monitoringu kvaliteta voda u akvakulturi

Merenje fizičkih, hemijskih, bioloških parametara je važno za praćenje stanja kvaliteta voda, a samim tim i veoma važno i u akvakulturi. Visokofrekventna merenja kvaliteta voda se poslednjih godina uspešno obavljaju i u Srbiji upotrebom multiparametarske sonde, jednostavne za rukovanje a složene po pitanju parametara koje može meriti u istom trenutku. Potreba za kontrolom kvaliteta vode raste sa povećanjem produkcije ribnjaka. Od ekstenzivnog gajenja, poluintezivnog, preko intenzivnog i superintenzivnog gajenja ribe, proces kontrole kvaliteta vode se usložnjava, dakle od povremenog kontrolisanja kvaliteta (mesečno, kod ekstenzivne proizvodnje), preko dnevne, kontrole na sat, i konačno do kontinuiranog praćenja kontrole kvaliteta (super-intenzivno). Praćenje kvaliteta senzorima i sondom je moguce u svim navedenim tipovima ribnjaka, ali je svakako primena takve metode najpotrebnija u superintenzivnoj ribnjačkoj proizvodnji

Broadening the urban sustainable energy diapason through energy recovery from waste: A feasibility study for the capital of Serbia

Metropolitan areas are large consumers of energy and there is a growing need to broaden the urban sustainable energy diapason and increase the share of renewable and sustainable energy in overall energy consumption. This is especially important in countries such as Serbia that have limited domestic fossil fuel resources and rely on energy imports, from the environmental, financial and energy security points of view. In the Serbian capital of Belgrade electricity is produced in coal-fired power plants that have been shown to be vulnerable to flooding and the district heating system is reliant on imported natural gas. The objective of this work was to perform a feasibility study of a combined heat and power municipal solid waste mass burn incineration facility in Belgrade. The feasibility study included a financial and an economic analysis. The City of Belgrade has a developed district heating system and locating the incineration facility next to an existing heating plant would enable the utilization of the heat energy produced by incineration and substitution of a portion of the imported natural gas currently used for district heating. The contributions of energy derived from waste incineration to the total energy consumption in Belgrade were also evaluated. The feasibility study showed that municipal solid waste incineration would be financially and economically positive and viable

Antimicrobial Resources for Disinfection of Potable Water Systems for Future Spacecraft

As human exploration adventures beyond low earth orbit, life support systems will require more innovation and research to become self-sustaining and durable. One major concern about future space travel is the ability to store and decontaminate water for consumption and hygiene. This project explores materials and technologies for possible use in future water systems without requiring point-of-use (POU) filtering or chemical additives such as iodine or silver that require multiple doses to remain effective. This experimentation tested the efficacy of a variety of antimicrobial materials against biofilm formation in a high shear CDC Biofilm Reactor (CBR) and some materials in a low shear Drip Flow Reactor (DFR) which(also utilizes ultra violet light emitting diodes (UVLEDs) as an antimicrobial resource. Most materials were tested in the CBR using the ASTM E 2562-07 1method involving the Pseudomonas aeruginosa and coupon samples that vary in their antimicrobial coatings and surface layer topographies. In a controlled environmental chamber (CEC), the CBR underwent a batch phase, continuous flow phase (CFP), and a harvest before analysis. The DFR portion of this experimentation was performed in order to assess the antimicrobial capabilities of ultraviolet-A LEDs (UV-A) in potable water systems. The ASTM E 2647-08 was modified in order to incorporate UV-A LEDs and to operate as a closed, re-circulating system. The modified DFR apparatus that was utilized contains 4 separate channels each of which contain 2 UV-A LEDs (1 chamber is masked off to serve as a control) and each channel is equipped with its own reservoir and peristaltic pump head. The 10 DFR runs discussed in this report include 4 initial experimental runs that contained blank microscope slides to test the UVA LEDs alone, 2 that incorporated solid silver coupons, 2 that utilized titanium dioxide (Ti02) coupons as a photocatalyst, and 2 runs that utilized silver coated acrylic slides. Both the CBR and DFR experiments were analyzed for microbial content via heterotrophic plate counts (HPC) and acridine orange direct counts (AODC). Ofthe materials used in the CBR, only two materials performed as anti~icrobials under high shear conditions (a reduction of 5 or more logs) showing a>7 log reduction in viable microbes

Modeling and design of an ultraviolet water disinfection system for long -term space missions

The nature of long-term space missions that involve extended stays by astronauts in locations beyond near-Earth orbit is such that complete water reuse is required. When combined with the high profile of these missions and other constraints imposed by NASA (e.g., restricted use of mercury, extreme space and energy limitations), this project represents a challenging design for water treatment. The proposed water recycling loop consists of a series of biological and physicochemical treatment processes, including disinfection as one of the last components in the water cycle. In conjunction with NASA\u27s interests in conducting long-duration human space travel, a UV system was designed based on XeBr excimer lamp technology. XeBr excimer lamps emit nearly monochromatic radiation at a characteristic wavelength of 282 nm. Baseline experiments conducted with a XeBr excimer lamp demonstrated its germicidal UV output to be highly effective for inactivation of Bacillus subtilis spores. A numerical prototype of this new reactor system was developed using a Lagrangian modeling scheme. The modeling approach involved simulation of fluid mechanics and particle trajectories using commercially available computational fluid dynamics software (FLUENT Inc.). Accurate simulations of the radiation intensity field within the reactor required the development of a new intensity field model. This new model, termed the Surface Power Apportionment for Cylindrical Excimer lamps (SPACE) radiation intensity model, was developed specifically for this purpose. The SPACE model accounts for the geometry and emission characteristics of the XeBr excimer lamp; it also provides a detailed accounting of the effects of absorption, dissipation, reflection, and refraction within the reactor system. The final design of the reactor was produced by an iterative procedure using these modeling tools, thereby allowing for optimization of reactor characteristics. Simulations of the behavior of the numerical prototype indicated high efficiency, in terms of microbial inactivation. The reactor system designed in this effort is being considered for inclusion in the next generation of NASA space vehicles. Reactors of this type could also be used in terrestrial applications, and may be of particular interest in applications where mercury use is restricted or undesirable

The Development and Performance of a Fluence Rate Distribution Model for a Cylindrical Excimer Lamp Supporting Information

Ultraviolet disinfection systems employing excimer lamp technology represent a suitable choice in situations where lamp mercury content is restricted, or otherwise undesirable. The XeBr* excimer lamp emits nearly monochromatic radiation at 282 nm, and dose-response experiments with Bacillus subtilis spores have shown that it is germicidally effective. A numerical model was developed to describe the fluence rate (E ) distribution emanating from a cylindrical XeBr* excimer lamp, based on liquid water or air as the surrounding medium. The E distribution model is based on physical phenomena that areknownto govern excimer lamps; the model also accounts for refraction, reflection, and absorbance effects of the quartz lamp envelope and the media surrounding the lamp. Measurements of the E distribution by local actinometry supported the validity of the numerical model. This model can be used as a component (submodel) of a more general model to simulate the behavior of photochemical reactors that employ excimer lamps as their source of electromagnetic radiation. Description:10 page

Ultraviolet Water Disinfection System for Long-Term Space Missions: Zorana Naunovic

22 slide

Complementary Drinking Water Disinfection: Outline

20 slides Provider Notes: Blatchley group repor

Process Performance of Ultraviolet Disinfection Systems for Long-term Space Missions

The effectiveness of ultraviolet (UV) disinfection is governed by the UV dose to which microorganisms are exposed. In treatment operations, all UV disinfection systems deliver a distribution of UV doses. The ability to accurately estimate the dose distribution delivered by an operating UV system is a critical aspect of its design. Moreover, the availability of tools to accurately predict the dose distribution for an existing UV system makes it possible to develop reliable, quantitative predictions of process performance in these systems. The dose distribution can be estimated by employing computational fluid dynamics (CFD) and UV radiation intensity field modelling. UV dose-distribution data is then coupled with UV dose-response behavior for target microorganisms to yield an estimate of process performance

Water Disinfection: UV Irradiation--EAC Presentation 2004

Disinfection is a component of an ALS closed-loop water recycling and purification system for long-term space missions. A proposed means of disinfection involves primary disinfection by ultraviolet (UV) irradiation and residual (secondary) disinfection by iodination. The goal of this research is to design an ultraviolet (UV) disinfection reactor that will inactivate pathogenic microorganisms present in the wastewater generated during long-term space missions. This design must ensure microbial inactivation efficacy, as well as minimize volume, mass, power and maintenance requirements. A mathematical model of the process has been developed to represent the fundamental physical and chemical behavior of the system. The validity of the model was assessed with continuous, flow-through experiments employing Bacillus subtilis spores as the target microorganism and a commercially available UV disinfection reactor. The validated model will be used to investigate alternative UV reactor geometries that can be incorporated into an ALS water purification system for long-term space missions. Related Documents:WM1, WM2, WM3, WM8 1 slid

Water Disinfection: UV Irradiation--Poster Presentation

Disinfection is a component of an ALS closed-loop water recycling and purification system for long-term space missions. A proposed means of disinfection involves primary disinfection by ultraviolet (UV) radiation and residual (secondary) disinfection by iodine. The effectiveness of UV disinfection is governed by the UV dose to which microorganisms are exposed. The UV dose is defined as the product of UV radiation intensity and exposure time (I?t). In a continuous-flow system, microorganisms will experience a broad range of local radiation intensities and exposure times; therefore, these systems will deliver a distribution of doses. The ability to accurately estimate the dose distribution delivered by an operating UV system is a critical aspect of its design. For this research, the flow field and particle trajectories in a UV reactor were simulated using computational fluid dynamics (CFD). The UV radiation intensity field was computed using a numerical method known as line-source integration (LSI). The outputs from the CFD and LSI simulations were then integrated to estimate the dose distribution delivered by the disinfection system. 1 slide Related Documents:WM1, WM2, WM3, WM