Anaerobic biodegradation of chlorinated aliphatic compounds using packed bed reactors

2006 ◽  
Vol 54 (10) ◽  
pp. 193-200 ◽  
Author(s):  
P. Mijaylova-Nacheva ◽  
A. Canul-Chuil
Keyword(s):  
Activated Carbon ◽  
Anaerobic Biodegradation ◽  
Packed Bed ◽  
Cod Removal ◽  
Electron Donors ◽  
Anaerobic Sludge ◽  
Biodegradation Rate ◽  
Aliphatic Compounds ◽  
Packed Bed Reactors ◽  
Support Materials

The feasibility of anaerobic packed bed reactors with tezontle (volcanic stone widely available in Mexico) and mineral granular activated carbon (GAC) was explored for the degradation of the main chlorinated aliphatic compounds present in the effluent from chemical industry for ethylene and polyvinyl chloride production. The biofilm on the support materials was developed using as inoculums anaerobic sludge. The biodegradation of the halogenated aliphatic compounds (1,2-dichloroethane; 1,1,1-trichloroethane; trichloroethylene and carbon tetrachloride) was possible without addition of external electron donors. High COD removal was obtained in the reactors with both materials. The use of GAC as a biomass support allows a complete biodegradation of the chlorinated aliphatic compounds at organic loads up to 1.24 kgCOD.m−3.d−1, with 94% of COD removal and with a biodegradation rate of 2.062 gCOD.kgGAC−1.d−1. The reactor with tezontle also had high biodegradation capacity, but the biodegradation of the 1,1-dichloroethene, which appeared as intermediate product, was not reached at the required level in the studied range of organic loads.

Anaerobic treatment of organic chemical wastewater using packed bed reactors

2006 ◽  
Vol 54 (10) ◽  
pp. 67-77 ◽  
Author(s):  
P. Mijaylova-Nacheva ◽  
B. Peña-Loera ◽  
S. Cuevas-Velasco
Keyword(s):  
Activated Carbon ◽  
Packed Bed ◽  
Treatment Method ◽  
Anaerobic Treatment ◽  
Cod Removal ◽  
Organic Chemical ◽  
Methanogenic Activity ◽  
Packed Bed Reactors ◽  
Suitable Treatment ◽  
Granulated Activated Carbon

The studied organic chemical wastewater had a high COD, 20–45 g/L, and low TSS, less than 200 mg/L, making anaerobic bio-filtration a suitable treatment method. The organic matter consisted of alcohols, amines, ketones and aromatic compounds, such as toluene and phenol. Granulated activated carbon (GAC) and a porous stone called tezontle, widely available in Mexico, were used as a bio-film support. Once inoculated, the mesophilic reactors with granulated activated carbon (GAC-BFs) reached stability with 80% COD removal in 40 days, while the reactors with tezontle material (tezontle-BF) required 145 days. Biodegradation of more than 95% was obtained with both support media: at organic loads less than 1.7 kg m−3 d−1 in tezontle-BF and with loads of up to 13.3 kg m−3 d−1 in GAC-BFs. The bio-filters with GAC allowed COD removal efficiency of 80% at a load as high as 26.3 kg m−3 d−1, while the same efficiency with tezontle was obtained at loads up to 4.45 kg m−3 d−1. The use of GAC as support material allows greater biodegradation rates than tezontle and it makes the bio-filters more resistant to organic increases, inhibition effects and toxicity. Methanogenic activity was inhibited at loads higher than 1.7 kg m−3 d−1 in bio-filters with tezontle and 22.8 kg m−3 d−1 in bio-filters with GAC. At loads lower than the previously mentioned, high methane production yield was obtained, 0.32–0.35 m3CH4/kg CODremoved. The biomass growth rates were low in the bio-filters with both kinds of material; however, a sufficiently high biomass holdup was obtained.

The Influence of Different Support Materials to Treatment Efficiency in Packed Bed Reactors

1992 ◽  
Vol 25 (1) ◽  
pp. 119-122 ◽  
Author(s):  
M. Roš ◽  
J. Vrtovšek ◽  
M. Dular
Keyword(s):  
Activated Carbon ◽  
Ceramic Material ◽  
Nitrogen Removal ◽  
Packed Bed ◽  
Packed Bed Reactor ◽  
Support Material ◽  
Packed Bed Reactors ◽  
Support Materials ◽  
Volumetric Loading ◽  
Granulated Activated Carbon

Biological treatment, especially nitrogen removal, in an upflow packed bed reactor with immobilised biomass was studied. As a support material granulated activated carbon (GAC), ceramic material (crush brick), brown coal and cut polyethylene tubes were used. The size of the support material was 4 to 6 millimetres. In laboratory scale studies pharmaceutical wastewater was treated. Volumetric loading was from 6.8 to 7.6 g/l/day. Results of investigations showed us that aerated packed bed reactors are usable for nitrogen removal because in the reactor originates aerobic and anoxic conditions. In anoxic cones the denitrification of nitrate, nitrite and ammonia ions takes place. The most effective systems for nitrogen removal were reactors filled with granulated activated carbon and with ceramic material. In the reactor with granulated activated carbon also colour from wastewater was degraded.

Maximal Biodegradation Rates of Chloroform and Trichloroethylene in Anaerobic Treatment

1992 ◽  
Vol 25 (3) ◽  
pp. 121-130 ◽  
Author(s):  
E. Rhee ◽  
R. E. Speece
Keyword(s):  
Loading Rate ◽  
Anaerobic Biodegradation ◽  
Anaerobic Treatment ◽  
Process Efficiency ◽  
Maximal Rate ◽  
Biodegradation Rate ◽  
Aliphatic Compounds ◽  
Metabolic Intermediates ◽  
Computer Controlled ◽  
Primary Substrate

Computer controlled reactors were used to determine the maximal rate of anaerobic biodegradation of chloroform and trichloroethylene using three important anaerobic intermediates (propionate, hydrogen, and acetate) as primary substrates. Maximal biodegradation rate was defined as that loading rate of chloroform and trichloroethylene which can be achieved while reducing process efficiency of the primary substrate to 50 %. The systems were controlled by a computer in response to the pH of the reactor in order to establish the unlimited equilibrium utilization levels of the three primary substrates and the chlorinated aliphatic compounds. From 89 to 99 % of chloroform and trichloroethylene was biodegraded at maximal loading rate of 15-109 mg/l of reactor-day in the primary substrate enrichment cultures. Biodegradation potentials, the affected class of microorganisms, and the fate and metabolic intermediates of chloroform and trichloroethylene also were examined.

Treatment of chemical-pharmaceutical wastewater in packed bed anaerobic reactors

2006 ◽  
Vol 54 (2) ◽  
pp. 157-163 ◽  
Author(s):  
P.M. Nacheva ◽  
B. Peña-Loera ◽  
F. Moralez-Guzmán
Keyword(s):  
Activated Carbon ◽  
Organic Compounds ◽  
Packed Bed ◽  
Organic Load ◽  
Support Material ◽  
Biological Degradation ◽  
Pharmaceutical Wastewater ◽  
Methanogenic Activity ◽  
Support Materials ◽  
Anaerobic Reactors

Biological degradation in packed bed anaerobic mesophilic reactors with five different support materials was studied for the treatment of chemical-pharmaceutical wastewater with high COD (23–31 g/L), which contains toxic organic compounds. Experimental up-flow bio-filters were operated at different organic loads for a two-year period. Removals of 80–98% were obtained in the reactors with sand, anthracite and black tezontle, but at relatively low organic loads, less than 3.6 kg m−3 d−1. The reactor with granular activated carbon (GAC) had a better performance; efficiencies higher than 95% were obtained at loads up to 17 kg m−3 d−1 and higher than 80% with loads up to 26 kg m−3 d−1. Second in performance was the reactor with red tezontle which allows COD removals higher than 80% with loads up to 6 kg m−3 d−1. The use of GAC as support material allows greater biodegradation rates than the rest of the materials and it makes the process more resistant to organic load increases, inhibition effects and toxicity. Methanogenic activity was inhibited at loads higher than 21.9 kg m−3 d−1 in the GAC-reactor and at loads higher than 3.6 kg m−3 d−1 in the rest of the reactors. At loads lower than the previously mentioned, high methane production yield was obtained, 0.32–0.35 m3CH4/kg CODremoved.

Anaerobic Semi-Continuous Culture Biodegradation of Dichlorophenols Containing an Ortho Chlorine

1987 ◽  
Vol 22 (3) ◽  
pp. 427-436 ◽  
Author(s):  
S.E. Hrudey ◽  
E. Knettig ◽  
P.M. Fedorak ◽  
S.A. Daignault
Keyword(s):  
Activated Carbon ◽  
Continuous Culture ◽  
Chlorine Atom ◽  
Degradation Process ◽  
Anaerobic Sludge ◽  
Continuous Cultures ◽  
Complete Mineralization

Abstract Rapid and preferential dechlorination of the ortho chlorine from 2,6-, 2,4- and 2,3- dichlorophenol substrates was observed in semi-continuous cultures inoculated with 50% unacclimated anaerobic sludge. The rate of further dechlorination depended on the position of the second chlorine atom. The dechlorination rates for the second chlorine ranked ortho > para > meta. Complete mineralization to methane was only observed in cultures fed 2,6-dichlorophenol. Addition of activated carbon to the anaerobic cultures showed some benefit to the degradation process.

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