Field application of a planted fixed bed reactor (PFR) for support media and rhizosphere investigation using undisturbed samples from full-scale constructed wetlands

2015 ◽  
Vol 72 (4) ◽  
pp. 553-560 ◽  
Author(s):  
A. B. Barreto ◽  
G. R. Vasconcellos ◽  
M. von Sperling ◽  
P. Kuschk ◽  
U. Kappelmeyer ◽  
...  
Keyword(s):  
Constructed Wetlands ◽  
Mobile Device ◽  
Fixed Bed ◽  
Field Application ◽  
Full Scale ◽  
Fixed Bed Reactor ◽  
Environmental Research ◽  
Operational Conditions ◽  
Undisturbed Samples ◽  
Real Scale

This study presents a novel method for investigations on undisturbed samples from full-scale horizontal subsurface-flow constructed wetlands (HSSFCW). The planted fixed bed reactor (PFR), developed at the Helmholtz Center for Environmental Research (UFZ), is a universal test unit for planted soil filters that reproduces the operational conditions of a constructed wetland (CW) system in laboratory scale. The present research proposes modifications on the PFR original configuration in order to allow its operation in field conditions. A mobile device to obtain undisturbed samples from real-scale HSSFCW was also developed. The experimental setting is presented with two possible operational configurations. The first allows the removal and replacement of undisturbed samples in the CW bed for laboratory investigations, guaranteeing sample integrity with a mobile device. The second allows the continuous operation of the PFR and undisturbed samples as a fraction of the support media, reproducing the same environmental conditions outside the real-scale system. Investigations on the hydrodynamics of the adapted PFR were carried out with saline tracer tests, validating the proposed adaptation. Six adapted PFR units were installed next to full-scale HSSFCW beds and fed with interstitial liquid pumped from two regions of planted and unplanted support media. Fourteen points were monitored along the system, covering carbon fractions, nitrogen and sulfate. The results indicate the method as a promising tool for investigations on CW support media, rhizosphere and open space for studies on CW modeling, respirometry, kinetic parameters, microbial communities, redox potential and plant influence on HSSFCW.

An Anaerobic Fixed Bed Reactor with a Porous Ceramic Carrier

1989 ◽  
Vol 21 (4-5) ◽  
pp. 77-86 ◽  
Author(s):  
Mitsuo Kawase ◽  
Tadashi Nomura ◽  
Tsuyoshi Majima
Keyword(s):  
Loading Rate ◽  
Unit Area ◽  
Porous Ceramic ◽  
Fixed Bed ◽  
Anaerobic Treatment ◽  
Fixed Bed Reactor ◽  
Operational Conditions ◽  
Treatment Performance ◽  
Fixed Bed Reactors ◽  
Highly Loaded

To date, a large number of studies on anaerobic fixed bed reactors have been reported, but there have been few studies on the application of this technology to thermophilic anaerobic treatment. One of the reasons for the small number of applications is the difficulty of attaching thermophilic anaerobic organisms to carriers. The study reported in this paper was conducted to examine the thermophilic treatment performance of an anaerobic fixed bed reactor containing a porous ceramic carrier (‘microbe immobilized ceramic', MIC) developed for the immobilization of anaerobic organisms. When boiled soybean wastewater (55,000 mg/l COD) was treated anaerobically at a high temperature (54°C) in a reactor where 31% of the volume was filled with the MIC carrier, it was found that highly loaded operation with up to 65 kg COD/m3/d was possible. The COD load per unit area of carrier surface under these operational conditions reached 0.397 kg COD/m3/d, and the performance of the reactor was excellent. Stable anaerobic treatment was achieved when the COD loading rate fluctuated from 26 to 51 kg COD/m3/d.

scholarly journals Solar-Driven Thermochemical Water-Splitting by Cerium Oxide: Determination of Operational Conditions in a Directly Irradiated Fixed Bed Reactor

Energies ◽  
2018 ◽  
Vol 11 (9) ◽  
pp. 2451 ◽  
Author(s):  
Lucía Arribas ◽  
José González-Aguilar ◽  
Manuel Romero
Keyword(s):  
Water Splitting ◽  
Cerium Oxide ◽  
Radiation Power ◽  
Fixed Bed ◽  
Fixed Bed Reactor ◽  
Solar Simulator ◽  
Operational Conditions ◽  
Concentrated Solar Energy ◽  
Production Of Hydrogen ◽  
Temperature Levels

Concentrated solar energy can be transformed into electricity, heat or even solar fuels, such as hydrogen, via thermochemical routes with high exergetic efficiency. In this work, a specific methodology and experimental setup are described, developed to assess the production of hydrogen by water splitting making use of commercial cerium oxide, ceria (CeO2), in a solarized reactor. A fixed bed reactor, directly irradiated by a 7 kWe high flux solar simulator (HFSS) was used. Released H2 and sample temperature levels were continuously monitored. Three tests were carried out consisting of three consecutive redox cycles each, with irradiances in the range of 1017–2034 kWm−2. It was necessary to achieve a compromise between sample temperatures (higher temperatures lead to higher reduction rates) and sample stability, since absorbed radiation can degrade a sample at lower temperature (1280–1480 °C) than in a conventional infrared oven (T > 2000 °C). Irradiating the surface of the sample with an irradiance of 2034 kWm−2 (270 W of total radiation power) during 9.5 min eventually degraded the sample, resulting in a conversion into stoichiometrically reduced oxide (Ce2O3) of 11%. A similar conversion was achieved (9.7%) after 2 min of irradiation at 270 W (100% of radiation), but without irreversibly damaging the sample.

The Optimization of an Ammonia Synthesis Reactor Using Genetic Algorithm

2009 ◽  
Vol 6 (1) ◽  
Author(s):  
Mohammad Taghi Sadeghi ◽  
Azam Kavianiboroujeni
Keyword(s):  
Genetic Algorithm ◽  
Ammonia Synthesis ◽  
Fixed Bed ◽  
Fixed Bed Reactor ◽  
Ammonia Production ◽  
Dimensional Model ◽  
Reactor Performance ◽  
One Dimensional ◽  
Operational Conditions ◽  
Quench Temperature

An industrial ammonia synthesis reactor was studied in order to optimize its operational conditions by means of increasing overall ammonia production. A heterogeneous, one-dimensional model and a two-dimensional rigorous model were utilized to evaluate the process behavior. The simulation results of the two models were compared with data from an industrial ammonia plant. The one-dimensional model was found to be adequate for optimization purposes. Applying the Genetic Algorithm (GA) as a powerful method for complex problems, the model was employed to optimize the reactor performance in varying its quench flows. The optimal temperature profile along the fixed bed reactor was studied by changing independent variables including the quench temperature and the quench flow rates. Optimization results show that the optimum quench temperature is about 615°K and that the optimum quench flows can enhance ammonia production rate by 3.3%.

scholarly journals PENGOLAHAN LIMBAH CAIR INDUSTRI PERCETAKAN UANG KERTAS (UTAS) MENGGUNAKAN PROSES BIOLOGIS ANAEROB

2018 ◽  
Vol 4 (1) ◽  
Author(s):  
Rudi Nugroho ◽  
Ikbal Mahmud ◽  
Nurtya Sulasmi
Keyword(s):  
Wastewater Treatment ◽  
Fixed Bed ◽  
Domestic Wastewater ◽  
Full Scale ◽  
Cod Removal ◽  
Laboratory Scale ◽  
Fixed Bed Reactor ◽  
Optimum Conditions ◽  
Treatment Technology ◽  
Anaerobic Bioreactor

A research of wastewater treatment technology come from money producing industry was conducted in laboratory scale using 10 lt of Anaerobic Fixed Bed Reactor. The money producing wastewater was treated by mixing with domestic wastewater with various compositions. The wastewater was fed into the bioreactor by draw and fill daily.The results show that the optimum of COD removal is 52,5%, optimum loading is 0, 95 g-COD/l/day and optimum flowrate is 0,5 l/day. The optimum compossition of money producing wastewater towards domestic wastewater is 30%. These optimum conditions can be used as a designed criteria for full scale of anaerobic bioreactor in the money producing industry. Katakunci : Wastewater, Anaerobic, Fixed Bed Reactor

scholarly journals Prediction of the fixed-bed reactor behavior for biotransformation with parallel enzyme deactivation using dispersion model: A case study on hydrogen peroxide decomposition by commercial catalase

2019 ◽  
Vol 21 (4) ◽  
pp. 106-115
Author(s):  
Ireneusz Grubecki ◽  
Katarzyna Kazimierska-Drobny
Keyword(s):  
Hydrogen Peroxide ◽  
Dispersion Model ◽  
Fixed Bed ◽  
Fixed Bed Reactor ◽  
Transfer Model ◽  
Hydrogen Peroxide Decomposition ◽  
Economic Point ◽  
Operational Conditions ◽  
Enzyme Deactivation ◽  
Peroxide Decomposition

Abstract The problems of process costs and pollution of residual waters in the textile industry require increasing attention due to the new ecological regulations and also those resulting from an economic point of view. Hence, the behavior of non-isothermal fixed-bed reactor applied for hydrogen peroxide decomposition by immobilized Terminox Ultra catalase attached onto the outer surface of glass beads was studied to determine the operational conditions at which hydrogen peroxide decomposition is most effectively. A dispersion model for bioreactor applied in this work, and verified experimentally, took into account the coupled mass and heat balances as well as the rate equation for parallel enzyme deactivation. The effect of feed temperature, feed flow rate, feed hydrogen peroxide concentration, and diffusional resistances were analysed. In the calculations the global effectiveness factor based on the external mass-transfer model developed previously was employed to properly predict the real bioreactor behavior.

scholarly journals Encapsulated catalase from Serratia genus for H2O2 decomposition in food applications

2018 ◽  
Vol 20 (4) ◽  
pp. 39-43 ◽  
Author(s):  
Katarzyna Czyzewska ◽  
Anna Trusek
Keyword(s):  
High Activity ◽  
Fixed Bed ◽  
Industrial Applications ◽  
Fixed Bed Reactor ◽  
Reactor Performance ◽  
Operational Conditions ◽  
H2o2 Decomposition ◽  
Wide Range ◽  
Immobilized Catalase ◽  
Food Applications

Abstract The recombinant catalase isolated from a psychrotolerant microorganism belonging to Serratia genus exhibits a high activity in a wide range of pH. Due to a great catalytic potential in operational conditions, it can be used in various industrial applications whereby it acts as a hydrogen peroxide scavenger. To reduce the cost of biocatalyst the enzyme encapsulation into a hydrogel structure was proposed. The obtained results showed a high activity of encapsulated catalase in acidic conditions (pH in range 4.4 - 6.6) and at low temperatures (6-15°C). Moreover, immobilized catalase exhibited a high stability in natural media, especially in milk. Its activity during peroxide decomposition in milk, the possibility of re-using, as well as the fixed bed reactor performance confirmed wide application possibilities. High values of enzyme and substrate concentrations led to the beads burst due to rapid oxygen diffusion from the capsules, thus they are limited.

Pyrolysis of sugarcane bagasse in a fixed bed reactor: Influence of operational conditions in the distribution of products

2017 ◽  
Vol 95 (12) ◽  
pp. 2249-2257 ◽  
Author(s):  
Edvan Vinícius Gonçalves ◽  
Carlos Teodoro ◽  
Fernanda Lini Seixas ◽  
Edmilson Antonio Canesin ◽  
Mara Heloisa Neves Olsen Scaliante ◽  
...  
Keyword(s):  
Sugarcane Bagasse ◽  
Fixed Bed ◽  
Fixed Bed Reactor ◽  
Operational Conditions

scholarly journals Steam Reforming of Glycerol for Hydrogen Production over Ni/SiO2 Catalyst

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
G. Sadanandam ◽  
N. Sreelatha ◽  
M. V. Phanikrishna Sharma ◽  
S. Kishta Reddy ◽  
B. Srinivas ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Fixed Bed ◽  
Product Distribution ◽  
Fixed Bed Reactor ◽  
Bet Surface Area ◽  
Molar Ratio ◽  
Water Mixture ◽  
Glycerol Water ◽  
X Ray ◽  
Operational Conditions

The performance of Ni/SiO2 catalyst for glycerol reforming has been investigated in fixed-bed reactor using careful tailoring of the operational conditions. In this paper, a commercial Engelhard catalyst has been sized and compared to gas product distribution versus catalyst size, water-to-carbon ratio, and stability of the catalyst system. Ni/SiO2 catalysts of three sizes (2×2, 2×4, and 3×5 mm) are evaluated using glycerol: water mixture at 600°C to produce 2 L H2 g−1 cat h−1. The results indicate that 3×5 mm size pellet is showing minimum coking and maintaining same level of conversion even after several hours of reforming activity. Whereas studies on 2×2 and 2×4 mm pellets indicate that carbon formation is affecting the reforming activity. Under accelerated aging studies, with 1 : 9 molar ratio of glycerol to water, 3 mg carbon g−1 cat h−1 was generated in 20 cycles, whereas 1 : 18 feed produced only 1.5 mg carbon g−1 cat h−1 during the same cycles of operation. The catalysts were characterized before and after evaluation by X-ray diffraction (XRD), BET surface area, scanning electron microscopy (SEM) with energy dispersive X-ray spectroscopy (EDAX), CHNS analysis, transmission electron microscopy (TEM), and X-ray photo electron spectroscopy (XPS).

scholarly journals Experimental Study on Hydrocracking Process of Asbuton Hydrocarbon Based on the Aromatic, and Waxy Residue Based on Paraffinic, by using Pt/Pd and γ-Alumina Catalyst in a Fixed Bed Reactor

2014 ◽  
Vol 14 (1) ◽  
pp. 59
Author(s):  
Bardi Murachman ◽  
Deendarlianto Deendarlianto ◽  
Nissaraly H.F. ◽  
Wakhid Hasyim
Keyword(s):  
Experimental Study ◽  
Reaction Mechanisms ◽  
Fixed Bed ◽  
Carbon Chain ◽  
Heating Time ◽  
Oil Refinery ◽  
Fixed Bed Reactor ◽  
Liquid Fuels ◽  
Operational Conditions ◽  
Hydrocracking Process

The studies on the hydrocracking process to obtain the fuel by cracking of the carbon chain from the hydrocarbon compound both in the form of gas and liquid fuels have been carried-out massively by researchers over three decade. In the present experimental study, heavy hydrocarbon represented by asphaltic base materials (named as Extracted Asbuton) and paraffinic (waxy residue from Cepu oil refinery) were used as the object of the study; by observing the differences of the reaction mechanisms and the results that can be obtained. Here the operational conditions such as pressure, temperature, and time as well as the kinds of catalyst were considered as the main parameters. The experiments were carried-out under the similar operating condition such as temperature around 350 – 500oC, pressure around 5 up to 15 atmospheres, and evaporation time was (1 – 3) hours. As a result, it was obtained (a) the higher the temperature, pressure, and heating time, the higher hydrocracking conversion both of hydrocarbons, (b) reaction mechanism of hydrocracking by using asphalt extract as the material follows the Model 3 of the present work, in which asphalt vapor was trapped in catalyst surface, meanwhile the waxy residue followed the Model 1, (c) under the same condition, the conversion of asphalt extract was smaller than waxy residue, and (d) the conversion of asphalt extract using Pt/Pd catalyst was higher than γ-Alumina catalyst.Keywords : Asbuton, Waxy Residue, Hydrocracking, Reaction Mechanisms.

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