All issues
Predecessor
Volume 15, Issue 9
Displaying 1-5 of 5 articles from this issue
- |<
- <
- 1
- >
- >|
ORIGINALS
-
Kuniharu YOSHIMOTO, Tadahiro MORI1992 Volume 15 Issue 9 Pages 587-592
Published: September 10, 1992
Released on J-STAGE: April 21, 2008
JOURNAL FREE ACCESSThe potential of sulfide flux formed by the anaerobic slime on the surface of the gravity sewer pipe wall was found to be 250μg·h-1 per lg of slime at 30°C. The density of slime is estimated to be 60mg·cm-3 and the effective thickness of slime is approximately 1-2mm. Therefore, the weight of unit slime becomes 6-12mg per 1cm2. The potential of sulfide flux formed by the slime is calculated to be 0.015-0.030g·h-1 per 1m2 of slime. By selecting the reaction-rate constants to be 1.07 per 1°C, it is concluded that the potential of sulfide flux formed by the slime is 0.008-0.015g·h-1 per 1m2 of slime at 20°C.View full abstractDownload PDF (501K) -
Kohei URANO, Yoko IWASE, Koichi FUJIE1992 Volume 15 Issue 9 Pages 593-599
Published: September 10, 1992
Released on J-STAGE: April 21, 2008
JOURNAL FREE ACCESSModel surface water which had been prepared by extracting a leaf mold and adding a corn steep liquor was treated by the fixed beds of glanular activated carbon(GAC) and sand. The removal efficiency of organic pollutants and the consumption of disolved oxygen in the both beds were studied.
In the sand column, 5-10% of the organic pollutants in the water was decomposed by the biofilm formed on the surface of the sand. GAC made from coconut shell showed a little adsorption effect beside the biofilm effect. On the other hand, GACs made from coal showed larger adsorption effect and biological effect due to the biological regeneration for a long time.View full abstractDownload PDF (570K) -
Yoshishige HAYASHI, Takuya KAWANISHI, Akihiro OKUYA, Hiroshi MATSUOKA1992 Volume 15 Issue 9 Pages 600-611
Published: September 10, 1992
Released on J-STAGE: April 21, 2008
JOURNAL FREE ACCESSThe fundamental characteristics for the operation of dewatering of an activated sludge with coaxial cylindrical electrodes, which has a feature that the activated sludge is dewatered without mechanical filtrations or the use of coagulating agents, were investigated. The experiment was performed by applying the interfacial electrokinetic phenomena to the activated sludge in a D.C. electric field and a dewatering model, estimating the charge time with electricity required to get the desired water content, was proposed on investigating the mechanism for dewatering in a cell.
The results show that the profile of the strength of electric field in the vicinity of anode is the most important variable for dewatering, and that it is more useful to reduce the generation of gases on electrode reactions at anode and cathode by preparing the pH of sludges in alkali fields.View full abstractDownload PDF (952K) -
Improvement in the Shape of ElectrodesYoshishige HAYASHI, Takuya KAWANISHI, Masafumi NISHINO, Hitoshi SAKAI1992 Volume 15 Issue 9 Pages 612-620
Published: September 10, 1992
Released on J-STAGE: April 21, 2008
JOURNAL FREE ACCESSThe best method for dewatering of activated sludges with a nonuniform electric field was investigated using a cylindrical cell with improved electrodes. The experiment was carried out in a D.C. electric field with a buffered solution of 0.03 mol·l-1 Na2B4O7·10H2O to keep the pH of activated sludge about 9.0.
The results showed that the buffer action was very effective for dewatering of an activated sludge, and that the stainless steel cylindrical cell with improved electrodes produced the profile of strong electric field in a cell. It was comfirmed that when the water separated from the sludge in a cell pumped out at 16 ml·min-1 with microtube-pump by the amount of about 50 wt% water in a sludge from 2 hours after the start of the turning on electricity, with 30 volt of external field almost all sludge particles were coagulated around the outside of the anode and the water contents in a dewatered activated sludge could be reduced up to about 60%, and further the amount of electricity was reduced.View full abstractDownload PDF (676K) -
Minoru TAKEDA, Jun-ichi KOIZUMI, Isei NAKAMURA, Ryuichiro KURANE1992 Volume 15 Issue 9 Pages 621-625
Published: September 10, 1992
Released on J-STAGE: April 21, 2008
JOURNAL FREE ACCESSThe effect of carbon sources on the growth of an actinomycete Nocardia amarae isolated from scum were investigated. Neutral fat medium allowed faster proliferation and greater cell yield of the actinomycete than glucose and organic acid media : polyester granules were intracellularly stored in the neutral fat medium. More than 7 days of lag were required for growth when hydrocarbon was used. Long chain fatty acids did not afford the cell growth.
The hydrophobic carbon sources brought about the floatation of the actinomycete, while the hydrophilic carbon sources allowed dispersive growth. Surface proteins of N. amarae exhibited affinity to hydrophobic substances. It was likely that hydrophobic property of cell exterior constructed by the surface proteins caused the capture of the actinomycete at the gas-liquid and oil-water interfaces together with that of cell wall.View full abstractDownload PDF (918K)
- |<
- <
- 1
- >
- >|