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Volume 30 (1994)
- Issue 2 Pages 65-
- Issue 1 Pages 1-
Volume 30, Issue 2
Displaying 1-8 of 8 articles from this issue
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MICHIHIKO IKE, HITOMI SUZUKI, MASANORI FUJITA1994 Volume 30 Issue 2 Pages 65-71
Published: December 15, 1994
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSDistribution of bacterial plasmids in a wastewater treatment plant using activated sludge process wasinvestigated. Each 10 strains of dominant bacteria, enteric bacteria, ampicillin (Ap) -, kanamycin (Km) -, tetracycline (Tc) -, and streptomycin (Sm) -resistant bacteria and bacteria which show resistant triply toAp, Km and Tc were isolated from the influent, activated sludge and effluent from Minami-Suitaactivated sludge treatment plant (Suita, Osaka, Japan) and their plasmid contents were examined. In all, 150plasmids were detected in 52 (25%) of 210 strains, 37 strains of which harbored multiple (2to9) plasmids. Although 40ut of 10 dominant bacteria isolated from the influent possessed plasmids, theywere observed in only one out of 10strains isolated from the activated sludge, suggesting that the plasmidpossession may give no or little advantage to their host in the aeration tank. On the other hand, ratio ofplasmid-harboring bacteria in the effluent was higher (4out of 10 strains) than that in the activatedsludge. Such tendency was observed for not only dominant bacterial population but also for otherantibiotic-resistant bacterial populations. Dominant bacteria mainly harbored small plasmids (smallerthan 5 kilobase (kb) ) . Plasmids larger than 30 kb, that can code gene transfer function, were alsodetected at frequency of 30%.View full abstractDownload PDF (818K) -
YUTAKA NAKAMURA, MUNETAKA ISHIKAWA1994 Volume 30 Issue 2 Pages 73-82
Published: December 15, 1994
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSSince the wastewater regulation on nitrogen and phosphate was enforced in October 1991, measures against stockbreeding waste have been an urgent subject. Furthermore, the consolidation of the standards on nitrogen and phosphate as for nutrient substrate is expected, because of the new environmental standards for public water established in June 1993.
But, it is difficult to expect the construction of advanced treatment plants for stockbreeding wastewater, as almost of all stockbreeding, such as hog and cattle raising and poultry farming, facilities are small scale and the burden of the wastewater treatment plant construction cost is heavy. For the solution of the problem, several stockbreeding farms are lumped together, and intensive farms are constructed. The wastewater from all of the farms in the lump is treated at one plant. Simultaneously, wastewaer treatment technologies applicable for small scale plant have been extensively developed.
An existing small scale oxidation ditch process plant, in which dairy cattle stockbreeding farms and domestic wastewater had been treated, was reconstructed and established effective advanced treatment with easy maintenance. The details of the reconstruction were as follows; 1) existing brush type sixsurface aerators were taken away, 2) a barrier was constructed in one section of the ditch, 3) two units of down draft type submerged turbine aerators were mounted at the upper stream of the barrier and mixed liquor with air bubbles were discharged down stream of the barrier. Thereby, effluent quality improved, especilly an increase in nitrogen removal and a clearing away of the problems involved in pH decrease, and maintenance become easy.
In this paper, test performance is explained and investigetion results based on the performance, applicability of this process to stock breeding wastewater treatment, advanced treatment object nitrogen removal and plant design factors are repoted.View full abstractDownload PDF (858K) -
TOHRU IYO, TSUNEO YOSHINO, SHIGERU OHNO1994 Volume 30 Issue 2 Pages 83-95
Published: December 15, 1994
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSWe investigated the treatment characteristics of the fluidized/expanded bed reactor (reactor A) using corn cob flour (CCF) as microcarriers and compared it to a UASB reactor (reactor B) .The fluidized/expanded bed reactor using CCF was used as a methane fermentation reactor of mesophilic two-phase digestion type, and synthetic wastewater used in this study was a mixtere of volatile fatty acids. The loading rates in both reactors were increased gradually by mainly decreasing the hydraulic retention time (HRT) .After 120 days, COD loading rate in reactor A was 30kg-CODcr⋅m-3⋅day-1 with a biogas production of about 90l⋅day-1.On the other hand, the COD loading rate in reactor B was over 20kg-CODcr⋅m-3⋅day-1 after 90 days with a biogas production of about 85l⋅day-1. The methane content and gas yield in both reactors were calculated to be 70-80% and 600l⋅kg-COD removed-1 for reactor A and 70-80% and 570l⋅kg-COD removed-l for reactor B. The lag between the start-up period in reactor A compared to that in reactor B appears to be affected by the amount of anaerobic seed sludge. The low C3-VFA removal rate caused the accumulation of propionic acid. The operation of both the reactors resulted in the accumulation of granule-like particles made up of anaerobic microorganisms. We found cocci, short rods and rod-type microorganisms on the surface of both sludges. These microorganisms resembled the genus of Methanococcus, Methanobacterium and Methanothix. From this data, it was concluded that CCF may be utilized as microcarriers for the fluidized/expanded bed reactor.View full abstractDownload PDF (1868K) -
TOHRU IYO, TSUNEO YOSHINO, SHIGERU OHNO1994 Volume 30 Issue 2 Pages 97-106
Published: December 15, 1994
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSWe investigated the suppressive effects on filamentous bulking by the addition of calcium polysulfide (CPS) . Laboratory experiments were conducted on three activated sludge systems with various loadings of CPS. The influent CPS in the three systems were 0, 100, and 200mg⋅l-1. All systems were operated under the same conditions, that is 0.24kg⋅m-3⋅day-1 of TOC volumetric loading rate, 24 hours of hydraulic retention time, temperature at 25°C, and were approximately operated at the same sludge loadings. A mixture of glucose and pepton was used as the substrate and easily caused the filamentous bulking. The mixed cultures developed in the systems mentioned possessed average SVI values of 400, 232, and 129ml⋅g-1 respectively. From microscopic and microbial observation, the high SVI value was caused by a high content of filamentous microorganisms in the developed mixed cultures. The series with CPS had different microflora compared with the control series with no loading of CPS. It was concluded that CPS suppressed the growth of filamentous microorganisms, and led to the growth of non-filamentous ones, i.e., Zooglea-like flocs.View full abstractDownload PDF (3566K) -
TAKUYA ODA, HIROYUKI ITO, HIROSHI YANO1994 Volume 30 Issue 2 Pages 107-112
Published: December 15, 1994
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSSummaries of succession of phytoplankton since 1954 in Sengari Reservoir, Hyogo Prefecture, Japan, are presented. The changes of dominant phytoplankters are associated with eutrophication of the reservoir. Between 1954 and 1964, the bacillariophytes were dominant most of the year.Afterwards the summer phytoplankton communities changed, that is, the chlorophytes were dominant between 1965 and 1972, and the cyanophytes were dominant between 1973 and 1982, although the bacillariophytes were dominant in the other seasons. Since 1984, the cyanophytes have disappeared and various species belonging to the chlorophytes, the cryptophytes, the bacillariophytes and the chrysophytes have been dominant throughout the years.View full abstractDownload PDF (907K) -
SOO-LIM RYU, KENJI FURUKAWA, MASANORI FUJITA1994 Volume 30 Issue 2 Pages 113-120
Published: December 15, 1994
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSThe preparation of acclimated marine denitrifying sludge (AMDS) with high denitirifying activity from activated sludge obtained from night soil treatment plant employing a sea water dilution system was successful within only one month of acclimatizing period. The optimum pH and temperature for denitrification by the AMDS were 6-8 and 30°C, respectively. AMDS was successfully immobilized by PVA-freezing method. Continuos denitrification experiments of NO3-N polluted synthetic sea water using column type bioreactor packed with these immobilized AMDS were carried out. Maximum allowable NO3-N loading rate to obtain 90% of NO3-N removal was determined experimentally to be 6.0 mg-NO3-N/g-pellet/d.View full abstractDownload PDF (3000K) -
KEISUKE IWAHORI, SHIGERU TATSUTA, MASANORI FUJITA, KOICHIRO YAMAKAWA1994 Volume 30 Issue 2 Pages 121-128
Published: December 15, 1994
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSA theoretical discussion on the biomass evaluation of pellet based on the respiratory activity was made and its experimental investigations were carried out using pellets formed by Aspergillus niger, of which average diameters were 2.0mm, 5.0mm and 10.0mm, respectively. The maximum respiration rate (Rr) was recognized when the initial TOC concentration exceeded about 5, 000mg/l. The biomass concentration is linearly related to the Rr value in case of the same pellet diameter. However, the Rr value decreased as the pellet diameter became larger in case of the same biomass concentration, because of the oxygen limitation. Comparing the theory based on the oxygen limitation with the experimental results, it was suggested that the area in 0.5-0.7mm from the pellet surface was an aerobic and active area not susceptible to the oxygen limitation. It was shown by the proposed theory that the maximum respiration rate was effective as an index of biomass evaluation of pellets, which were formed by the five-day culture and of which diameter was more than 5.0mm.View full abstractDownload PDF (2596K) -
SEIKO KANEMATU1994 Volume 30 Issue 2 Pages 129-134
Published: December 15, 1994
Released on J-STAGE: February 26, 2010
JOURNAL FREE ACCESSA report about microorganisms adhered to a river bed in the spring and the summer seasons run on Japanese Journal of Water Treatment Biology, Vol, 29, No.1 (1993) .This time microorganisms adhered to river bed were investigated during the autumn and the winter seasons at every points. A cycle of a year about microorganisms adhered to river bed was round off.The dominant species of the microorganisms adhered to the river bed were also investigated separately.The saprobity in the surface water in terms of saprobic index of the species was following;
autumn winter
Points 1, 2, 4, 6 1, 2, 3, 4, 8 : oligo-saprobity s=1.0±0.5
Points 3, 5, 8, 9, 10, 12 5, 6, 7, 9, 11, 12 : β-meso-saprobity s=2.0±0.5
Points 7, 11 10 : α-meso-saprobity s=3.0±0.5
About 10 species were observed at every points in the four seasons. At the same time, discript the result of the investigation on microorganisms quantities. Microorganisms indicate the past career of water quality for a fairly long time. But because of the differences in temperature, environment of a river bed, the water current and the time of the year the dominant species assume a different aspect. So a deeper understanding of the water environment is the best measure to prevent water pollution. Needless to say, the origin of water pollution should be managed and controlled. Cleaning and putting a river side in good condition is very important. And is necessary to care for the change of a river bed by bridging work.View full abstractDownload PDF (491K)
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