巻号一覧
38 巻 (2002)
- 4 号 p. 175-
- 3 号 p. 117-
- 2 号 p. 57-
- 1 号 p. 1-
38 巻, 4 号
選択された号の論文の7件中1～7を表示しています
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佐藤 義典, 長坂 實上, 丁 国際2002 年 38 巻 4 号 p. 175-182
発行日: 2002/12/15
公開日: 2010/02/26
ジャーナル フリーThe effect of agitation on the treatment performance and sludge settleability in a SBR process in the operating condition that no NH4-N were detected in effluent were investigated. The influent used in this study was domestic wastewater. Two agitation methods: stirring by using a stirrer and a pump were used for this study. In the condition (controlled system) that diameter of stirring impeller was 90mm and stirring speed was 100rpm, the treatment performance and settleability of activated sludge was very stable. However, in the condition that diameter of stirring impeller installed with two sheets (impellers) was 50mm and stirring speed was over 190rpm, efficiency of oxygen transfer was increased, but floc of activated sludge was segmented. It was observed that suspended solid (SS) in effluent was increased with the increase of stirring speed. Moreover, the increase of stirring speed resulted in apparent increase of sludge volume index (SVI) and caused the deterioration of sludge settleability. The flock diameter of the activated sludge dccreased from 82μm to 65μm due to the increased stirring speed from 100rpm to 190rpm.抄録全体を表示PDF形式でダウンロード (2384K) -
黒木 征一朗, 洪 静蘭, 中岡 元信, 古川 憲治2002 年 38 巻 4 号 p. 183-192
発行日: 2002/12/15
公開日: 2010/02/26
ジャーナル フリーThe development of effective and economical treatment of textile waste water is required. Simultaneous removal of dye and nitrogen by photo-dependent denitrifying sludge (PDDS), which has the potential to remove the color and nitrate nitrogen under denitrifying and lighting conditions, was developed. A successful continuous dye treatment system was demonstrated by bench-scale experiments. The optimal C/N ratio for the degradation of dyes by PDDS was determined to be 1.5: 1. The specific removal rate of Acid Blue 92 (AB-92) decreased with an increase in nitrate loading rate. And, the specific removal rate of AB-92 increased with a decrease in MLSS concentration. Bench scale treatment system which has nitrifying reactor and denitrifying reactor was constructed and its treatment capabilities were experimentally evaluated through continuous treatment of synthetic textile waste water. The nitrifying reactor in this system could nitrify the synthetic textile waste water which contains urea as organic nitrogen and several kinds of dyes. The denitrifying reactor could reduce the color intensity under light-denitrifying condition by PDDS.抄録全体を表示PDF形式でダウンロード (1150K) -
IKBAL, SHIGERU MORIMURA, TORU SHIGEMATSU, KENJI KIDA2002 年 38 巻 4 号 p. 193-201
発行日: 2002/12/15
公開日: 2010/02/26
ジャーナル フリーDistributions of bacterial populations and degradation of sewage sludge components in a two-series digestion process with liquefaction of thickened surplus sludge (hereinafter called the modified two-series digestion) and in a conventional mono-phase digestion (hereinafter called the conventional digestion) process were investigated. A high level of 2.7 × 1010 MPN/ml acidogenic bacteria in the thermophilic liquefaction reactor of the modified two-series digestion was observed at a volatile suspended solid (VSS) volumetric loading rate of 14 g/l⋅d. This count was three orders of magnitude higher than that of all other anaerobic bacteria enumerated in the reactor. At a VSS loading rate of 6 g/l⋅d, the levels of hydrogenotrophic and aceticlastic methanogens in the mesophilic digestor of the modified two-series digestion were 1.2 × 108 and 1.9 × 107 MPN/ml, respectively, which were 3 and 1.5 times higher than those in the reactor of the conventional digestion. In the modified two-series digestion, the degradation efficiencies of lipid, protein, carbohydrate and lignin in the sludge were 69.8%, 57.7%, 46.8% and 24.5%, respectively, at a VSS loading rate of 3 g/l⋅d. These values were over 10% higher than those of the conventional digestion at the same loading rate, except for lignin which was only 5% higher. The specific resistances of sludges after treatment by the modified two-series and conventional digestions were 4.58 × 1011 m/kg and 6.15 × 1011 m/kg, respectively. The modified two-series digestion process demonstrated performance superior to the conventional digestion process.抄録全体を表示PDF形式でダウンロード (1040K) -
ZEN'ICHIRO KAWABATA, PATHMALAL MARAKKAL MANAGE, YASUYUKI MIYAI, MAKOTO ...2002 年 38 巻 4 号 p. 203-210
発行日: 2002/12/15
公開日: 2010/02/26
ジャーナル フリーThis is a first report of the use of cavitation treatment, an innovative method, to suppress phytoplankton biomass. It was found that cavitation treatment immediately kil1ed some algal cells in pond waters; about 75% of Peridinium sp. died when exposed to cavitation for one minute at 1800 rpm of the shaft rotation in a cylinder. The effectiveness of cavitation for causing algal death varied with different species. These results showed the possibility of using cavitation treatment to suppress algal biomass for a short time. Experiments combining different cavitation powers and treatment times with different species are required if we are to develop an effective system for suppressing specific algal blooms in particular bodies of water.抄録全体を表示PDF形式でダウンロード (838K) -
WATARU TAKATSUJI, MOTONOBU NAKAOKA, YUKIHIRO SAKAI, KENJI FURUKAWA2002 年 38 巻 4 号 p. 211-218
発行日: 2002/12/15
公開日: 2010/02/26
ジャーナル フリーIn a conventional activated sludge aeration tank, organic nitrogen was almost completely converted to ammonium but very little was converted to oxidized forms of nitrogen (nitrite and nitrate) . Nitrification and denitrification in the aerated unit process, though, was achieved by using three submerged cells with porous sides consisting of nonwoven materials for retention of biomass. When synthetic wastewater with nitrogen only in organic form was fed directly into a cell (as opposed to the surrounding aeration tank), T-N decreased from 42 to 30 mg/l and TOC levels, from 110 to 10 mg/l. Because virtually all activated sludge was attached to cell walls, there was essentially no excess sludge wastage over 100 days of operation. Denitrification efficiency using the novel apparatus was shown to be effected by TOC and alkalinity in the influent wastewater as well as dissolved oxygen levels and the method of influent feed. When wastewater was fed simultaneously into two cells, versus only one, the T-N removal efficiency improved from 34% to 45%. Effluent T-N was shown to decrease with a decrease in DO in the aeration tank and careful control of TOC and alkalinity levels in the wastewater feed allowed for nitrogen removal efficiencies as high as 75%.抄録全体を表示PDF形式でダウンロード (2967K) -
KINYA UCHIHASHI, MASAHIRO TAKEO, SEIJI NEGORO2002 年 38 巻 4 号 p. 219-229
発行日: 2002/12/15
公開日: 2010/12/09
ジャーナル フリーTwo 2, 6-naphthalenedisulfonate (2, 6NDS) degrading bacteria were isolated from the activated sludge of a wastewater treatment plant and designated NDS-1 and NDS-2. Only strain NDS-1 showed a floc-forming ability in such media as synthetic wastewater. Sequence analysis of the partial 16S ribosomal DNA (rDNA) sequence of strain NDS-1 revealed that it is a strain closely related to Pigmentiphaga kullae, which was recently established in the family Alcaligenaceae, and that the sequence was in perfect agreement with that of strain NDS-2. Strain NDS-1 could mineralize 2, 6NDS and 1, 6-naphthalenedisulfonate (1, 6NDS) with sulfate ion release, but showed no assimilating or desulfonating activity on 8 other sulfonated naphthalenes, indicating that it has a very narrow substrate specificity. 2, 6NDS-induced NDS-1 cells exhibited a high oxygen uptake for 2, 6NDS, while non-induced cells showed a very low oxygen uptake, demonstrating that 2, 6NDS oxidation is inducible in strain NDS-1.抄録全体を表示PDF形式でダウンロード (3159K) -
史 江紅, 中井 智司, 細見 正明2002 年 38 巻 4 号 p. 231-235
発行日: 2002/12/15
公開日: 2010/02/26
ジャーナル フリーIn this paper, the biodegradability of estrogens; estrone (E1), 17β-estradiol (E2), and ethynylestradiol (EE2) ; was evaluated using a nitrifying activated sludge (NAS) . NAS could degrade E1, E2, EE2 with the biodegradation rate constants, i.e.0.035h-1, 0.056h-1, 1.3h-1 respectively, indicating that E2 was the most biodegradable among the three estrogens.
It should be noted that biodegradation of E2 produced E1, which was confirmed by a spike test on a reversed phase high performance liquid chromatography equipped with an electrochemical detector (HPLC-ECD) . An sequential reaction analysis where it was assumed that E2 was biodegraded to an unknown compound via E1 showed that E1 was firstly produced by biodegradation of E2. As for the unknown intermediates of E1 and EE2 were detected by HPLC-ECD. Based on the result that these electrochemically detectable compounds were eluted faster than the parent compounds, i.e. E1 and EE2, On the HPLC-ECD, it was suggested that more polar compounds containing phenolic group than the three estrogens were produced by NAS. Because significant decrease of the peak area of these compounds on the HPLC-ECD chromatogram was observed during biodegradation of E1 and EE2, it was suggested that NAS could cleavage phenolic group of E1 and EE2.抄録全体を表示PDF形式でダウンロード (544K)
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