Fibrous Carrier Research Articles

Evaluation on a pilot-scale attached-growth pond system treating domestic wastewater

Pilot-scale experiments on attached-growth ponds (AGP) had been conducted to investigate the feasibility of improving waste stabilization ponds (WSP) performance through the incorporation of attached-growth media (AGM) or the so-called artificial fibrous carriers in the pond water. Better removal efficiencies of COD, BOD 5 and NH 4 -N had been obtained in the AGP than in the conventional WSP through the comparative studies. On the basis of these results, a pilot-scale AGP system had been built and run, which had shown to have great advantages and stabilities with better effluent quality in performance in comparison with conventional WSP.

Removal of nitrogen from coal gasification and coke plant wastewaters in A/O submerged biofilm-activated sludge (SBF-AS) hybrid system

Experimental research involving both laboratory and full-scale studies has been carried out to evaluate the nitrification-denitrification process carried out in a submerged biofilm (in anoxic zone)-activated sludge (in oxic zone) (SBF-AS) hybrid system for nitrogen removal from coal gasification and coke plant wastewaters. The anoxic reactor in the system was packed with fibrous carriers fixed on plastic plates of circular form for the attached growth of submerged biofilm with facultative denitrifying bacteria as dominant species to carry out denitrification, and the activated sludge process was used in the aerobic reactor for nitrification. As the denitrifying and nitrifying bacteria live under anoxic and aerobic conditions respectively in the hybrid system, the process was tested under the conditions of high organic and ammonia loading rates and short hydraulic retention time(HRT). The experimental results show that ammonia nitrogen, NH3-N removal is between 94% and 99.9% and COD removal between 80% and 95%.

Production of Gibberellic Acid in Gibberella fujikuroi Adhered onto Polymeric Fibrous Carriers

Gibberella fujikuroi cells were immobilized on the surface of fibrous carriers with copolymers obtained by a radiation polymerization technique. The gibberellic acid (GA) production in the immobilized cells was investigated by varying the immobilization conditions and using various monomers. GA productivity in cells immobilized with the carrier-covered copolymer of hydrophylic hydroxyethyl acrylate and hydrophobic trimethylpropane triacrylate was higher than that in the free cells. The stability of the immobilized cells was evaluated by repetition of the batch fermentation. The immobilized cells produced GA with high stability. GA productivity by immobilized cells varied with the chemical nature of the carriers covered by the polymers.

Characteristics of filamentous cells immobilized with ionic-hydrophobic polymers prepared by a radiation polymerization method

Abstract Filamentous cells of Trichoderma reesei were immobilized using a fibrous carrier covered with ionic-hydrophobic polymers, prepared by radiation copolymerization. The effect of the ionic properties of the polymers was investigated by changing the monomer composition in a trimethylpropane triacrylate (A-TMPT) — acrylic acid (AA) or methacrylic acid diethylaminoethyl ester (DEAEMA) system. More positive charge or less negative charge in the polymers led to an increase in the growth of the cells immobilized on their surface. Enzyme productivity in the immobilized cells with AA-A-TMPT polymer was higher than with a DEAEMA-A-TMPT polymer.

Intensification of a Pond System by Fibrous Carriers

A study was carried out on the intensification of a pond system, consisting of an anaerobic pond, a facultative pond and a polishing pond, in Anda City, Heilongjiang Province, by fibrous carriers packed in the anaerobic pond, by means of which the performance of the pond system was remarkably improved with higher removal capacities and efficiencies for SS, BOD5, COD, TN, TP and bacteria, compared with the conventional system. The mechanism for the intensified effect was found to be ascribed to the increase of biomass in the form of biofilm attached to the surface of the fibrous carriers and more even distribution of the biomass in the pond. A mathematical model based on the complete mixed flow pattern was developed both for the intensified and conventional anaerobic pond, and the organic degradation rate constant value K in the former was found to be much greater than that in the latter. The microbial communities in both the ponds were also observed.

Nitrogen Removal by a Submerged Biofilm Process with Fibrous Carriers

A study on nitrogen removal by submerged biofilm attaching on fibrous carriers in A/0 process was carried out, with the emphasis put on finding out the optimal conditions for nitrification and denitrification with highest nitrogen removal. The influence of return flow ratio of nitrified effluent on the removal capacities of the system for organic substances and nitrogen was studied as well.

Cellulase production in Trichoderma reesei immobilized with polymeric fibrous carriers

Trichoderma reesei mycelia were immobilized on polymeric fibrous carriers covered with various polymers, using a radiation polymerization technique. The mycelia were firmly attached to the surface of the fibril of the carrier covered with hydrophobic polymers. Cellulase production was in some cases higher by immobilized mycelia than by free mycelia and was affected by the chain structure of the polymer.Key words: Trichoderma reesei, immobilization, radiation, cellulase, fibril.

Effect of antimicrobial protection on tolerance to hepatic chemoembolization with a fibrous collagen carrier.

The effect of antimicrobial prophylaxis on tolerance to hepatic embolization and chemoembolization with collagen particles was examined in porcine liver. Embolization in the 36 animals consisted of hepatic artery injection of 3 mL of collagen (10 mg/mL) alone or combined with one to three drugs (cisplatin, mitomycin, and doxorubicin). Embolization was performed with or without antimicrobial protection, and the animals were killed at 5 days for gross and histologic evaluation of liver and for bacterial culture. When present, liver damage consisted of focal to whole-lobe necrosis. Liver damage was correlated with positive bacterial culture (P less than .002) and was reduced by antimicrobial protection. Vessel recanalization was inhibited by addition of drug to collagen (P less than .001) and by lack of antimicrobial protection (P less than .001). Perivascular necrosis was directly related to vessel size (P = .0001). Antimicrobial prophylaxis is recommended to enhance hepatic chemoembolization safety.

Immobilization of microbial cell and yeast cell and its application to biomass conversion using radiation techniques

Abstract The recent results of immobilization of cellulase-producing cells and ethanol-fermentation yeast by radiation were reported. The enzyme of cellulase produced by immobilized cells was used for saccharification of lignocellulosic wastes and immobilized yeast cells were used for fermentation reaction from glucose to ethanol. The wastes such as chaff and bagasse were treated by γ-ray or electron-beam irradiation in the presence of alkali and subsequent mechanical crushing, to form a fine powder less than 50 μm in diameter. On the other hand, Trichoderma reesei as a cellulase-producing microbial cell was immobilized on a fibrous carrier having a specific porous structure and cultured to produce cellulase. The enzymatic saccharification of the pretreated waste was carried out using the produced cellulase. The enhanced fermentation process to produce ethanol from glucose with the immobilized yeast by radiation was also studied. The ethanol productivity of immobilized growing yeast cells thus obtained was thirteen times that of free yeast cells in a 1:1 volume of liquid medium to immobilized yeast cells.

Chromafol®—ein neues material für die chromatographie in flächenanordnung

Chromafol® — a new material for flat-bed chromatography The material consists of an organic porous polymer fixed in a fibrous carrier having the function of a binding agent. Chromatographic properties have been studied on a series of sheets (thin layers) of a macroporous styrene-ethylvinylbenzene-divinylbenzene terpolymer (70% by weight) with cellulose as a fibrous binding agent.