Selective reduction of lead sulfate containing slag using the fluidized bed reactor

TiO2-coated granular activated carbon was employed for the removal of toxic microcystin-LR from water. High surface area of the activated carbon provided sites for the adsorption of microcystin-LR, and the adsorbed microcystin-LR migrated continuously onto the surface of TiO2 particles which located mainly at the exterior surface in the vicinity of the entrances of the macropores of the activated carbon. The migrated microcystin-LR was finally degraded into nontoxic products and CO2 very quickly. These combined roles of the activated carbon and TiO2 showed a synergistic effect on the efficient degradation of toxic microcystin-LR. A continuous flow fluidized bed reactor with the TiO2-coated activated carbon could successfully be employed for the efficient photocatalytic of microcystin-LR.

Download Full-text

Influence of Seeding Conditions on Initial Biofilm Development during the Startup of Anaerobic Fluidized Bed Reactors

Water Science & Technology ◽

10.2166/wst.1989.0219 ◽

1989 ◽

Vol 21 (4-5) ◽

pp. 157-165 ◽

Cited By ~ 2

Author(s):

F. Ehlinger ◽

J. M. Audic ◽

G. M. Faup

Keyword(s):

Fluidized Bed ◽

Future Development ◽

Protein Concentration ◽

Specific Activity ◽

Fluidized Bed Reactor ◽

Fluidized Bed Reactors ◽

Support Material ◽

Biofilm Development ◽

Initial Biofilm

The characterization of the biofilm of an anaerobic fluidized-bed reactor was completed under standard conditions. The distribution of the fixed protein concentration depended on the level in the reactor. The protein concentration reached 1520 µg.g−1 of support at the top of the reactor and only 1200 µg.g−1 at the bottom after 504 hours of operation but the specific activity of the biofilm was 33×10−4 µM acetate.h−1.mg−1 proteins at the bottom and only 26×10−4 µM.h−1.mg−1 at the top. The efficiency of a fluidized bed reactor and the composition of the biofilm changed with an increase of the pH from 7 to 8.5 during the seeding of the support material. Future development of the biofilm and the specific activity of the support were affected.

Download Full-text

The Kinetics of Glucose Decomposition with Sulfate Reduction in the Anaerobic Fluidized Bed Reactor

Water Science & Technology ◽

10.2166/wst.1993.0092 ◽

1993 ◽

Vol 28 (2) ◽

pp. 135-144 ◽

Cited By ~ 3

Author(s):

S. Matsui ◽

R. Ikemoto Yamamoto ◽

Y. Tsuchiya ◽

B. Inanc

Keyword(s):

Sulfate Reduction ◽

Fluidized Bed ◽

Kinetic Equations ◽

Fluidized Bed Reactor ◽

Order Reaction ◽

First Order Reaction ◽

First Order ◽

Glucose Decomposition ◽

Reaction Equations ◽

Kinetics Of

Using a fluidized bed reactor, experiments on glucose decomposition with and without sulfate reduction were conducted. Glucose in the reactor was mainly decomposed into lactate and ethanol. Lactate was mainly decomposed into propionate and acetate, while ethanol was decomposed into propionate, acetate, and hydrogen. Sulfate reduction was not involved in the decomposition of glucose, lactate, and ethanol, but was related to propionate and acetate decomposition. The stepwise reactions were modeled using either a Monod expression or first order reaction kinetics in respect to the reactions. The coefficients of the kinetic equations were determined experimentally. The modified Monod and first order reaction equations were effective at predicting concentrations of glucose, lactate, ethanol, propionate, acetate, and sulfate along the beight of the reactor. With sulfate reduction, propionate was decomposed into acetate, while without sulfate reduction, accumulation of propionate was observed in the reactor. Sulfate reduction accelerated propionate conversion into acetate by decreasing the hydrogen concentration.

Download Full-text

Experimental Study of Hydrodynamic Characteristics and CO2 Absorption in Producer Gas Using CaO-sand Mixture in a Bubbling Fluidized Bed Reactor

International Journal of Chemical Reactor Engineering ◽

10.2202/1542-6580.2445 ◽

2011 ◽

Vol 9 (1) ◽

Author(s):

M.M. Mahadzir ◽

Z.A. Zainal

Keyword(s):

Experimental Study ◽

Fluidized Bed ◽

Fluidized Bed Reactor ◽

Hydrodynamic Characteristics ◽

Producer Gas ◽

Sand Mixture ◽

Bubbling Fluidized Bed

Download Full-text

Biological granulated activated carbon fluidized bed reactor for atrazine remediation

Water Science & Technology ◽

10.2166/wst.2004.0845 ◽

2004 ◽

Vol 49 (11-12) ◽

pp. 215-222 ◽

Cited By ~ 11

Author(s):

M. Herzberg ◽

C.G. Dosoretz ◽

S. Tarre ◽

M. Beliavski ◽

M. Green

Keyword(s):

Fluidized Bed ◽

Fluidized Bed Reactor ◽

Batch Adsorption ◽

Pseudomonas Sp ◽

Partial Penetration ◽

Biofilm Carrier ◽

Degradation Rates ◽

Degrading Bacteria ◽

Atrazine Degradation ◽

Granulated Activated Carbon

To show that an adsorbing biofilm carrier (GAC) can be advantageous for atrazine bioremediation over a non-adsorbing carrier, fluidized bed (FB) reactors were operated under atrazine limiting concentrations using Pseudomonas sp. strain ADP as the atrazine degrading bacteria. The following interrelated subjects were investigated: 1) atrazine adsorption to GAC under conditions of atrazine partial penetration in the biofilm, 2) differences in atrazine degradation rates and 3) stability of atrazine biodegradation under non-sterile anoxic conditions in the GAC reactor versus a reactor with a non-adsorbing biofilm carrier. Results from batch adsorption tests together with modeling best described the biofilm as patchy in nature with covered and non-biofilm covered areas. Under conditions of atrazine partial penetration in the biofilm, atrazine adsorption occurs in the non-covered areas and is consequently desorbed at the base of the biofilm substantially increasing the active biofilm surface area. The double flux of atrazine to the biofilm in the GAC reactor results in lower effluent atrazine concentrations as compared to a FB reactor with a non-adsorbing carrier. Moreover, under non-sterile denitrification conditions, atrazine degradation stability was found to be much higher (several months) using GAC as a biofilm carrier while non-adsorbing carrier reactors showed sharp deterioration within 30 days due to contamination of non-atrazine degrading bacteria.

Download Full-text