A continuous, multistage tower fermentor. II. Analysis of reactor performance

1970 ◽  
Vol 12 (3) ◽  
pp. 465-482 ◽  
Author(s):  
Edvard A. Falch ◽  
Elmer L. Gaden
Keyword(s):  
Reactor Performance ◽  
Tower Fermentor

The anaerobic treatment of a ligno-cellulosic substrate offering little natural pH buffering capacity

1998 ◽  
Vol 38 (4-5) ◽  
pp. 29-35 ◽  
Author(s):  
C. J. Banks ◽  
P. N. Humphreys
Keyword(s):  
Ph Control ◽  
Anaerobic Treatment ◽  
Buffering Capacity ◽  
Single Stage ◽  
Stable Operation ◽  
Reactor Performance ◽  
Two Stage ◽  
Ph Buffering ◽  
Stage System ◽  
The Stability

The stability and operational performance of single stage digestion with and without liquor recycle and two stage digestion were assessed using a mixture of paper and wood as the digestion substrate. Attempts to maintain stable digestion in both single stage reactors were unsuccessful due to the inherently low natural buffering capacity exhibited; this resulted in a rapid souring of the reactor due to unbuffered volatile fatty acid (VFA) accumulation. The use of lime to control pH was unsatisfactory due to interference with the carbonate/bicarbonate equilibrium resulting in wide oscillations in the control parameter. The two stage system overcame the pH stability problems allowing stable operation for a period of 200 days without any requirement for pH control; this was attributed to the rapid flushing of VFA from the first stage reactor into the second stage, where efficient conversion to methane was established. Reactor performance was judged to be satisfactory with the breakdown of 53% of influent volatile solids. It was concluded that the reactor configuration of the two stage system offers the potential for the treatment of cellulosic wastes with a sub-optimal carbon to nitrogen ratio for conventional digestion.

Anaerobic/aerobic biodegradation of pentachlorophenol using GAC fluidized bed reactors: optimization of the empty bed contact time

1997 ◽  
Vol 36 (6-7) ◽  
pp. 107-115 ◽  
Author(s):  
Gregory J. Wilson ◽  
Amid P. Khodadoust ◽  
Makram T. Suidan ◽  
Richard C. Brenner
Keyword(s):  
Fluidized Bed ◽  
Oxygen Demand ◽  
Aerobic Biodegradation ◽  
Fluidized Bed Reactors ◽  
Reactor Performance ◽  
Reactor Operation ◽  
Significant Cost ◽  
Second Stage ◽  
Primary Substrate ◽  
Chlorinated Phenolic Compounds

An integrated reactor system has been developed to remediate pentachlorophenol (PCP) containing wastes using sequential anaerobic and aerobic biodegradation. Anaerobically, PCP was degraded to predominately equimolar concentrations (>99%) of monochlorophenol (MCP) in two GAC fluidized bed reactors at Empty Bed Contact Times (EBCTs) ranging from 18.6 to 1.15 hours. However, at lower EBCTs, MCP concentrations decreased to less than 10% of the influent PCP concentration suggesting mineralization. The optimal EBCT was determined to be 2.3 hours based on PCP conversion to MCPs and stable reactor operation. Decreasing the EBCT fourfold did not inhibit degradation of PCP and its intermediates, thus allowing removal of PCP at much lower detention time and resulting in a significant cost advantage. Analytical grade PCP was fed via syringe pumps into two fluidized bed reactors at influent concentrations of 100 mg/l and 200 mg/l, respectively. Acting as the primary substrate, ethanol was also fed into the reactors at concentrations of 697 and 1388 mg/l. Effluent PCP and chlorinated phenolic compounds were analyzed weekly to evaluate reactor performance. Biodegradation pathways were also identified. 3-chlorophenol (CP) was the predominant MCP and varied simultaneously with 3,5-dichlorophenol (DCP) concentrations. Likewise, 4-CP concentrations varied simultaneously with 3,4-DCP concentrations. A second stage aerobic GAC fluidized bed reactor was added after the anaerobic reactor to completely mineralize the remaining MCP and phenols. Data show no presence of phenol and MCP in the effluent or on the GAC. Overall, the chemical oxygen demand (COD) fed to the system was reduced from 75 g/d in the influent to less than 1.5 g/d in the effluent.

Mass Transfer Limited Wet Oxidation in Trickle-Bed Reactor

1998 ◽  
Vol 63 (11) ◽  
pp. 1938-1944 ◽  
Author(s):  
Vratislav Tukač ◽  
Jiří Vokál ◽  
Jiří Hanika
Keyword(s):  
Supported Catalyst ◽  
Reaction Rates ◽  
Gas Transfer ◽  
Wet Oxidation ◽  
Reactor Performance ◽  
Catalytic Wet Oxidation ◽  
Environmental Application ◽  
Trickle Bed Reactor ◽  
Fine Glass ◽  
Trickle Bed

Catalytic activity of CuO-supported catalyst in phenol oxidation, and the influence of reaction conditions, viz. temperature (125-170 °C), oxygen partial pressure (1-7 MPa) and liquid feed (30-760 ml h-1), in the continuous operation using 17.9 mm i.d. trickle-bed reactor is presented. The hydrodynamic impact on the three-phase trickle-bed reactor performance in an environmental application of catalytic wet oxidation was also investigated. The results of trickle-bed operation were strongly influenced by wetting efficiency. An insufficient catalyst wetting can be to compensated by filling the catalyst bed voids by fine glass spheres. In the case of the gas transfer limited reaction, a better wetting of the catalyst can lead to worse reactor performance due to lower reaction rates.

Effect of the Scale-Up Process on the Reactor Performance within the Riser: Simulation Using Ozone Decomposition

2021 ◽  
Author(s):  
Congjing Ren ◽  
Yao Yang ◽  
Zhengliang Huang ◽  
Jingyuan Sun ◽  
Yongrong Yang ◽  
...  
Keyword(s):  
Scale Up ◽  
Ozone Decomposition ◽  
Reactor Performance

scholarly journals A Cyanobacteria-Based Biofilm System for Advanced Brewery Wastewater Treatment

2020 ◽  
Vol 11 (1) ◽  
pp. 174
Author(s):  
Konstantinos P. Papadopoulos ◽  
Christina N. Economou ◽  
Athanasia G. Tekerlekopoulou ◽  
Dimitris V. Vayenas
Keyword(s):  
Wastewater Treatment ◽  
Biomass Production ◽  
Low Cost ◽  
Oxygen Demand ◽  
Dry Weight ◽  
Surface Hydrophobicity ◽  
Reactor Performance ◽  
Brewery Wastewater ◽  
Kjeldahl Nitrogen ◽  
Supporting Materials

Algal/cyanobacterial biofilm photobioreactors provide an alternative technology to conventional photosynthetic systems for wastewater treatment based on high biomass production and easy biomass harvesting at low cost. This study introduces a novel cyanobacteria-based biofilm photobioreactor and assesses its performance in post-treatment of brewery wastewater and biomass production. Two different supporting materials (glass/polyurethane) were tested to investigate the effect of surface hydrophobicity on biomass attachment and overall reactor performance. The reactor exhibited high removal efficiency (over 65%) of the wastewater’s pollutants (chemical oxygen demand, nitrate, nitrite, ammonium, orthophosphate, and total Kjeldahl nitrogen), while biomass per reactor surface reached 13.1 and 12.8 g·m−2 corresponding to 406 and 392 mg·L−1 for glass and polyurethane, respectively, after 15 days of cultivation. The hydrophilic glass surface favored initial biomass adhesion, although eventually both materials yielded complete biomass attachment, highlighting that cell-to-cell interactions are the dominant adhesion mechanism in mature biofilms. It was also found that the biofilm accumulated up to 61% of its dry weight in carbohydrates at the end of cultivation, thus making the produced biomass a suitable feedstock for bioethanol production.

Improvement of the Inertial Fusion Energy Reactor Performance by Means of UF4and ThF4

2003 ◽  
Vol 43 (2) ◽  
pp. 230-249 ◽  
Author(s):  
Sebahattin Ünalan ◽  
S. Orhan Akansu ◽  
Hanifi Saraç
Keyword(s):  
Fusion Energy ◽  
Inertial Fusion ◽  
Inertial Fusion Energy ◽  
Reactor Performance ◽  
Fusion Energy Reactor

scholarly journals Development of downflow hanging sponge (DHS) reactor as post treatment of existing combined anaerobic tank treating natural rubber processing wastewater

2016 ◽  
Vol 75 (1) ◽  
pp. 57-68 ◽  
Author(s):  
Takahiro Watari ◽  
Trung Cuong Mai ◽  
Daisuke Tanikawa ◽  
Yuga Hirakata ◽  
Masashi Hatamoto ◽  
...  
Keyword(s):  
Natural Rubber ◽  
Loading Rate ◽  
Oxygen Demand ◽  
Nitrogen Loading ◽  
Post Treatment ◽  
Organic Loading Rate ◽  
Anammox Bacteria ◽  
Rrna Gene ◽  
Sequencing Analysis ◽  
Reactor Performance

Conventional aerated tank technology is widely applied for post treatment of natural rubber processing wastewater in Southeast Asia; however, a long hydraulic retention time (HRT) is required and the effluent standards are exceeded. In this study, a downflow hanging sponge (DHS) reactor was installed as post treatment of anaerobic tank effluent in a natural rubber factory in South Vietnam and the process performance was evaluated. The DHS reactor demonstrated removal efficiencies of 64.2 ± 7.5% and 55.3 ± 19.2% for total chemical oxygen demand (COD) and total nitrogen, respectively, with an organic loading rate of 0.97 ± 0.03 kg-COD m−3 day−1 and a nitrogen loading rate of 0.57 ± 0.21 kg-N m−3 day−1. 16S rRNA gene sequencing analysis of the sludge retained in the DHS also corresponded to the result of reactor performance, and both nitrifying and denitrifying bacteria were detected in the sponge carrier. In addition, anammox bacteria was found in the retained sludge. The DHS reactor reduced the HRT of 30 days to 4.8 h compared with the existing algal tank. This result indicates that the DHS reactor could be an appropriate post treatment for the existing anaerobic tank for natural rubber processing wastewater treatment.

Production of hydrocarbons from fatty acids and animal fat in the presence of water and sodium carbonate: Reactor performance and fuel properties

Fuel ◽  
2012 ◽  
Vol 94 ◽  
pp. 262-269 ◽  
Author(s):  
Bernd Weber ◽  
Ernst A. Stadlbauer ◽  
Sabrina Stengl ◽  
Mohammad Hossain ◽  
Andreas Frank ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Sodium Carbonate ◽  
Fuel Properties ◽  
Reactor Performance ◽  
Animal Fat
Sign in / Sign up

Export Citation Format

Share Document