scholarly journals Performance of different biofilters in a recirculating system for rainbow trout farming

2016 ◽  
pp. 5426-5440 ◽  
Author(s):  
Iván Sánchez O ◽  
Dolly Revelo R ◽  
Álvaro Burbano M ◽  
Roberto García C ◽  
Camilo Guerrero R ◽  
...  

Objective. To evaluate the performance of different biofilters in a recirculating aquaculture system (RAS) for trout farming. Materials and methods. It was used a 1m3 plastic tank for fries farming; fabric bags to solids retention; a submersible pump; a constant water level and flow distribution box; six up flow biofilters in 3” PVC tube; sand of D10=0.45mm as carrier. The reactors were operated at local temperature and with hydraulic retention time (HRT) of 11 min, the biofilters were inoculated in the next way: R1-Control: RAS water; R2-Fish culture farm sludges; R3- Water from aerated lagoon of Antanas landfill (AL); R4-Aquarium sediments; R5- Aerated lagoon of AL sludges; R6-Sludges from sulfidogenic reactor of AL. The weight gain (WG) and the food conversion (FC) were evaluated, some physic-chemical parameters were monitored and the nitrogen and suspended solids removal efficiency were evaluated. Results. The WG of the cultured animals was 1.58 g/d and the FC was 1.41. There were no differences for ammonium and nitrite removal between the reactors; the average removal efficiencies were: ammonium 4.78%, nitrite 27.2%, nitrate 32.3%, suspended solids 37.5%; R4 and R5 reactors presented the best performance on nitrate removal, with average efficiencies of 47.4% and 42.8%. R3 presented the best SS removal with an average of 58.2%. Conclusions. The RAS water treatment system guaranteed appropriated liquid quality conditions for trout farming; the most efficient reactor for removal of the different forms of nitrogen was the inoculated with the aerated lagoon of AL sludges.RESUMEN Objetivo. Evaluar el desempeño de diferentes biofiltros en un sistema de recirculación (SRA) para cultivo de trucha arcoiris. Materiales y métodos. Se utilizó: un tanque de 1m3 para cultivo de alevines, bolsas de lienzo para retención de sólidos, bomba sumergible, caja de nivel constante y distribución de flujo, seis biofiltros en tubo de PVC de 3”, arena con D10=0.45mm como medio soporte. Los biofiltros se operaron a temperatura ambiente y con tiempo de retención hidráulica (TRH) de 11 min, se inocularon así: R1-Control: Aguas del SRA; R2-Lodos estación piscícola; R3-Agua Laguna aireada relleno sanitario Antanas (RSA); R4-Sedimentos acuarios; R5-Lodos laguna aireada RSA; R6-Lodos reactor sulfidogénico RSA. Se evaluó la ganancia de peso (GP) y la conversión alimenticia (CA), se monitorearon parámetros físico-químicos y se evaluó la eficiencia de remoción de nitrógeno y sólidos suspendidos. Resultados. La GP de los animales fue de 1.58 g/d y la CA de 1.41. No hubo diferencias para remoción de amonio ni nitritos entre reactores; las eficiencias medias de remoción fueron: amonio 4.78%, nitrito 27.2%, nitrato 32.3%, sólidos suspendidos 37.5%. Los reactores R4 y R5 presentaron mejor remoción de nitratos, con eficiencias medias de 47.4% y 42.8%. El R3 reportó la mejor remoción de SS con promedio del 58.2%. Conclusiones. El sistema de tratamiento del agua en el SRA garantizó condiciones de calidad del líquido, apropiadas para el cultivo de la trucha; el reactor más eficiente para la remoción de las formas de nitrógeno evaluadas fue el inoculado con lodos de la laguna aireada del RSA.

1987 ◽  
Vol 22 (3) ◽  
pp. 474-490 ◽  
Author(s):  
R.L. Droste ◽  
S.R. Guiot ◽  
S.S. Gorur ◽  
K.J. Kennedy

Abstract Anaerobic treatment of dilute synthetic wastewater (300-1,000 mg chemical oxygen demand/L using laboratory upflow sludge blanket filter reactors with and without effluent recycle is described. Treatment of dilute synthetic wastewater at hydraulic retention times less than 1 and 2 h in reactors without and with recycle, respectively, resulted in biomass washout as the solids retention time decreased to less than 12 d. Reseeding would be required to operate at these critical hydraulic retention times for extended periods. Treatment of dilute synthetic wastewater at hydraulic retention times between 3-12 h resulted in soluble COD removal efficiencies between 84-95% treating 300 mg COD/L. At a 3 h hydraulic retention time, solids retention time of 80 d and stable reactor biomass concentrations of 25 g volatile suspended solids/L were maintained.


1999 ◽  
Vol 40 (3) ◽  
pp. 57-65 ◽  
Author(s):  
Martin M. Karpiscak ◽  
Robert J. Freitas ◽  
Charles P. Gerba ◽  
Luis R. Sanchez ◽  
Eylon Shamir

An integrated wastewater treatment facility, consisting of upper (solids separators, anaerobic lagoons, and aerobic ponds) and lower (wetland cells) subsystems, has been built to replace the lagoon at a dairy in Arizona, USA. The collection sump of the new waste treatment facility collects all dairy wastewater outflow. Wastewater is then pumped to solids separators, and flows by gravity to anaerobic ponds and aerobic ponds. The upper subsystem is expected to treat the water sufficiently so that the wetland cells may achieve further pollutant reductions. The lower subsystem, comprised of 8 surface wetland cells with an approximate surface area of 5,000 m2, receives outflow from the ponds. The cells are planted with cattail (Typha domingensis), soft-stem bulrush (Scirpus validus), and reed (Phragmites australis). After treatment is completed via the lagoons and ponds followed by the wetland cells, the wastewater can be reused to flush barns or to irrigate crops. Performance of the overall system is evaluated by measuring physical, chemical and biological parameters in water samples taken from selected locations along the treatment system. Chemical parameters studied include biochemical oxygen demand, pH, total suspended solids, nitrogen species. Biological monitoring included coliforms (total and fecal) and Listeria monocytogenes.


2012 ◽  
Vol 65 (3) ◽  
pp. 403-409 ◽  
Author(s):  
A. Ya. Vanyushina ◽  
Yu. A. Nikolaev ◽  
A. M. Agarev ◽  
M. V. Kevbrina ◽  
M. N. Kozlov

The process of anaerobic thermophilic digestion of municipal wastewater sludge with a recycled part of thickened digested sludge, was studied in semi-continuous laboratory digesters. This modified recycling process resulted in increased solids retention time (SRT) with the same hydraulic retention time (HRT) as compared with traditional digestion without recycling. Increased SRT without increasing of HRT resulted in the enhancement of volatile substance reduction by up to 68% in the reactor with the recycling process compared with 34% in a control conventional reactor. Biogas production was intensified from 0.3 L/g of influent volatile solids (VS) in the control reactor up to 0.35 L/g VS. In addition, the recycling process improved the dewatering properties of digested sludge.


1994 ◽  
Vol 30 (9) ◽  
pp. 133-139 ◽  
Author(s):  
M. F. Dahab ◽  
S. Sirigina

In this paper, a study on using fixed-film biological denitrification to remove nitrates from water supplies is reported. Fixed-film biological systems have not been used in water supply systems in the U.S. although they are proven to be efficient and economical for removing nitrates with the reason being the possibility of imparting residual organics, suspended solids and bacteria to the treated water. In this research, fixed-film upflow biodenitrification columns were operated under carbon-starved conditions and the effluent was treated with a granular activated carbon (GAC) and sand filter system (combined in one unit) to remove residual organics and suspended matter. The system resulted in an average effluent turbidity of 0.8 NTU, and COD and total suspended solids (TSS) concentrations of 5.7 and 0.6 mg/L, respectively.


2015 ◽  
Vol 10 (1s) ◽  
Author(s):  
Bruno Boz ◽  
Giuseppina Pipitone ◽  
Bruna Gumiero ◽  
Paolo Bazzoffi ◽  
Luigi Sansone

Several studies have described the effectiveness of vegetated buffer strips, interposed between the cultivated areas and water bodies, in removal of suspended solids and other pollutants such as Glyphosate conveyed through surface runoff. This monitoring study has quantified the effects of a 5-metre wide herbaceous buffer zone, adjacent to a vineyard, built according to the Standard 5.2 of Cross-compliance (M.D. 27417). The amount of runoff generated was 3.9% of the total annual rainfall, with negligible differences in terms of volume after flowing through the buffer zone. The effectiveness of the buffer zone in suspended solids removal was, in terms of mass balance, of 45.5%. The glyphosate outputs from the vineyard, unlike in other experiences, were negligible and therefore it was not possible to evaluate the efficiency of the buffer zone in removing it. This is due to the low rainfall occurred in the period following distribution that has favoured <em>in situ</em> degradation of Glyphosate.


2018 ◽  
Vol 18 (2) ◽  
pp. 286 ◽  
Author(s):  
Aris Mukimin ◽  
Agus Purwanto

In general, wastewater treatment by physical, chemical and biological methods are only focused on TSS, BOD and COD removals that the effluent still contains anion pollutant as NO2- and S2-. Electrochemical technology is a proper method for those pollutants treatment due to its fast process, easy operation and minimum amount of sludge. Electrocatalytic reactor with 8 L capacity using Ti/RuIrO2 cylinder as anode and Fe plate as cathode was arranged and applied to treat anion pollutants. Hydraulic retention time (30, 60, 90 and 120 min), salt concentration (250, 500 and 750 mg/L) and voltage (4, 5, and 6 V) were chosen as operation variables and NO2- and S2- concentrations as parameter indicators. Nitrite removal efficiency reached 75 and 99.7% after 60 and 120 min of electrolysis, respectively, while sulfide could obtain higher efficiency, i.e., 97 and 99.9% after 60 and 90 min, respectively, at operation variables of potential of 5 V and salt of 500 mg/L. Removal process is dominated by indirect oxidation mechanism by HClO/ClO- oxidators generated at anode surface as intermediate products. The lifespan of electrode and electric consumption are two main factors of operation cost. Electric consumed was 0.452 kWh per 1 g nitrite removed.


2018 ◽  
Vol 44 ◽  
pp. 00072
Author(s):  
Małgorzata Komorowska-Kaufman ◽  
Filip Ciesielczyk ◽  
Alina Pruss ◽  
Teofil Jesionowski

The paper presents the results of analyzes of the granulometric composition of suspended solids in backwash water from biological activated carbon (BAC) filters and its changes during sedimentation. Backwash water samples were taken during backwashing of two pilot filters after different filtration time. It was found that regardless of the concentration of suspended solids in the collected backwash water, particle sizes vs. their percentage volume contributions for all samples were similar. Particle sizes were in the range of 2–100 μm. However, the two-hour sedimentation for most of the samples proved to be effective (total suspended solids removal up to 93%), which is caused by self-coagulation of the sample.


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