Solid, slightly soluble phosphorus compounds as nutrient source in activated sludge treatment of forest industry wastewaters

1997 ◽  
Vol 35 (2-3) ◽  
pp. 131-138 ◽  
Author(s):  
Pirjo-Riitta Rantala ◽  
Hannu Wirola
Keyword(s):  
Activated Sludge ◽  
The Other ◽  
Phosphorus Compounds ◽  
Forest Industry ◽  
Phosphorus Concentration ◽  
Nutrient Source ◽  
Sludge Treatment ◽  
Grain Sizes ◽  
Soluble Phosphorus ◽  
The Mean

The aim of the study was to determine if solid, slightly soluble compounds can be used as nutrient source in activated sludge treatment plants instead of liquid phosphoric acid. Four different solid materials were tested in lab-scale solubility tests to find compounds which are least soluble. Two materials were chosen for further studies: apatite and raw phosphate. The use of apatite and raw phosphate as nutrient source was studied in lab-scale activated sludge reactors along with a control reactor where phosphorus was added in liquid form. The phosphorus dosage, measured as elementary phosphorus, was the same for all three reactors. The reactors were fed with pre-clarified chemi-thermomechanical pulp mill (CTMP) wastewater. There were no significant differences in the reductions of organic matter between the three reactors. The mean effluent concentration of total phosphorus was 3 mg P/l in the control reactor and less than 1 mg P/1 in the other two reactors. The soluble phosphorus concentration was more than 2 mg P/l in the control reactor and less than 0.5 mg P/l in the other two. Apatite was an even better nutrient source than raw phosphate. Further lab-scale tests were conducted using two different grain sizes of apatite. No significant differences were found between the studied grain sizes (<0.074 mm and 0.074 mm-0.125 mm). Apatite was then used in full-scale at a CTMP-mill two different times. The experiments showed that the mean concentrations of phosphorus can be reduced radically by using apatite as a nutrient source instead of liquid phosphorus. Solid phosphorus compounds are a viable alternative to reduce the phosphorus load from forest industry wastewater treatment plants.

Elimination of human enteric viruses during conventional waste water treatment by activated sludge

1986 ◽  
Vol 32 (12) ◽  
pp. 922-925 ◽  
Author(s):  
Pierre Payment ◽  
Sylvie Fortin ◽  
Michel Trudel
Keyword(s):  
Waste Water ◽  
Water Treatment ◽  
Activated Sludge ◽  
Waste Water Treatment ◽  
Enteric Viruses ◽  
Sludge Treatment ◽  
Poliovirus Type ◽  
The Mean ◽  
Human Enteric Viruses ◽  
Type 3

The present study was undertaken to determine if viruses were selectively eliminated during waste water treatment. Human enteric viruses were detected at all steps of treatment in a conventional activated sludge waste water treatment plant. Liquid overlays and large volume sampling with multiple passages on BGM cells permitted the detection of poliovirus (serotypes 1, 2, and 3), coxsackievirus B (serotypes 1, 2, 3, 4, and 5), and echovirus (serotypes 3, 14, and 22), as well as reoviruses. The mean virus concentration was 95.1 most probable number of infectious units per litre (mpniu/L) in raw sewage, 23.3 in settled water, 1.4 in effluent after activated sludge treatment, and 40.3 mpniu/L in sludge samples. All samples of raw sewage and settled water, 79% of effluent water, and 94% of sludge samples contained viruses. The mean reduction was 75% after settling and 98% after activated sludge treatment. Poliovirus type 3 was rarely isolated after the activated sludge treatment, but was still detected in about one-third of the sludge samples. Reoviruses and coxsackieviruses were detected at similar rates from all samples and appear to be more resistant to the activated sludge treatment than poliovirus type 3. Poliovirus types 1 and 2 were present in almost every sample of raw sewage and settled water and still found in about half of the effluent and sludge samples, indicating a level of resistance similar to that of reoviruses and coxsackieviruses.

Effect of sludge type on poliovirus association with and recovery from sludge solids

1981 ◽  
Vol 27 (3) ◽  
pp. 279-287 ◽  
Author(s):  
Oscar C. Pancorbo ◽  
Phillip R. Scheuerman ◽  
Samuel R. Farrah ◽  
Gabriel Bitton
Keyword(s):  
Activated Sludge ◽  
The Other ◽  
Virus Concentration ◽  
Poliovirus Type ◽  
Virus Adsorption ◽  
The Mean ◽  
Degree Of Association ◽  
Aerobic Sludge ◽  
Aerobically Digested

Sludge type was found to affect the degree of association between seeded poliovirus type 1 (LSc) and sludge solids. The mean percent of solids-associated viruses for activated sludge mixed liquors, anaerobically digested sludges, and aerobically digested sludges was 57.2, 70.4, and 94.7, respectively. The degree of association between poliovirus and sludge solids was significantly greater for aerobically digested sludges than for the other two sludge types. Sludge solids associated viruses were eluted using 0.05 M glycine buffer, pH 10.5–11.0, and subsequently concentrated by organic flocculation. The effectiveness of the glycine method in the recovery of solids-associated viruses was also found to be affected by sludge type. Significantly lower mean poliovirus recovery was found for aerobically digested sludges (14.5%) than for mixed liquors or anaerobically digested sludges (72.3 and 60.2%, respectively). The eluent used in the method was not as effective in dissociating the virus from aerobic sludge solids as it was for the other two sludge types. All other virus adsorption–elution steps of the method (i.e., virus concentration steps) were equally effective in poliovirus recovery for all three sludge types. It is suggested that future methods developed for the recovery of viruses from sludges be evaluated for the various sludge types likely to be tested.

Iron Phosphate and Anaerobic Digestion

1970 ◽  
Vol 5 (1) ◽  
pp. 102-128
Author(s):  
A. Grikis ◽  
G.M. Cornwall
Keyword(s):  
Anaerobic Digestion ◽  
Activated Sludge ◽  
Iron Phosphate ◽  
Phosphorus Concentration ◽  
Batch Reactors ◽  
Biological Sludge ◽  
Soluble Phosphorus ◽  
Chemical Sludge ◽  
Biological Component ◽  
Expected Increase

Abstract This research was undertaken in order to clarify some of the apparent inconsistencies in the literature concerning the fate of phosphates in iron phosphate sludges during anaerobic digestion. Three anaerobic batch reactors were started and acclimatized to a feed of waste activated sludge. While one digester was maintained as a control, with a feed of only biological sludge, the other two digesters were loaded with different mixtures of biological sludge and iron phosphate sludge. When the digesters had stabilized with respect to influent and effluent total phosphorus, critical measurements of all the phosphorus fractions were made. The soluble phosphorus in the control digester remained the same from the influent to the effluent. This observation seems to contradict the expected increase in soluble phosphates during the anaerobic digestion process. When the activated sludge was mixed with the ferric phosphate sludge, it was observed that a reduction in soluble phosphorus took place. After this combined biological-chemical sludge had been digested anaerobically, an increase in the soluble phosphorus concentration, to a level roughly equivalent to that in the biological component of the influent, was observed.

Is a rainfall simulator useful for estimating phosphorus runoff from pastures — a question of scale-dependency?

2002 ◽  
Vol 42 (7) ◽  
pp. 953 ◽  
Author(s):  
P. S. Cornish ◽  
R. Hallissey ◽  
E. Hollinger
Keyword(s):  
Management Practices ◽  
Agricultural Land ◽  
Dairy Farm ◽  
Particulate Phosphorus ◽  
Phosphorus Concentration ◽  
Catchment Scale ◽  
Rainfall Simulator ◽  
Soluble Phosphorus ◽  
The Mean ◽  
Mean Concentration

Research on management practices that aim to reduce phosphorus in runoff from agricultural land has been hampered by the need to study large catchments over relatively long time periods to account for both the temporal and spatial effects of scale. The concentrations of pollutants such as phosphorus in runoff, similarly to suspended sediment, may diminish with increasing catchment scale. However, the runoff from well-covered dairy pastures contains predominantly soluble rather than particulate phosphorus. This paper examines the hypothesis that the concentration of soluble phosphorus in runoff from dairy pastures is insensitive to scale, and that small-plot rainfall simulators can be used to estimate concentrations of phosphorus in runoff at the farm or subcatchment scale.Over 2 years and 9 runoff events, the mean concentration of soluble phosphorus in runoff from a 140 ha dairy farm (0.95 mg/L) was not significantly different from a 4 ha representative subcatchment (paddock) within the dairy farm (0.66 mg/L). Relative concentrations from the 2 sources varied between events, depending on the duration of the runoff event. This variation was attributed to changes in the relative importance of different source areas as events progressed; runoff from the more distant parts of the larger catchment area, typically in higher positions in the landscape, apparently increased in importance in longer events.A hand-held rainfall simulator, with plots of only 1 m2, provided a quick, useful estimate of soluble phosphorus concentration in runoff. The mean concentration of soluble phosphorus in runoff from simulated rainfall at 9�locations in the 4 ha paddock (0.64 mg/L) was very similar to the value obtained from the paddock over a 2-year period (0.66 mg/L). We conclude that the concentration of soluble phosphorus in runoff from dairy pasture does depend on scale, and other variables, but the effect of scale was small for the catchment studied. A rainfall simulator may be used, with adequate replication, to estimate the soluble phosphorus concentrations in runoff that could be expected from dairy pastures over much larger areas.

Isolation and Identification of Actinomycetes Present in Activated Sludge Scum

1988 ◽  
Vol 20 (11-12) ◽  
pp. 257-263 ◽  
Author(s):  
Mesut Sezgin ◽  
Mary P. Lechevalier ◽  
Philip R. Karr
Keyword(s):  
Activated Sludge ◽  
Environmental Conditions ◽  
Treatment Plant ◽  
The Other ◽  
Plant Design ◽  
Isolation And Identification ◽  
Sludge Treatment ◽  
Common Organism ◽  
Plant Samples

A study was carried out to isolate and identify actinomycetes present in activated sludge scum. Samples from two activated sludge treatment plants were analyzed. One hundred and five strains were isolated. The predominant organism in both treatment plant samples was Nocardiaamarae. Fifty-one strains of N. amarae were isolated. The second most common organism (24 strains) was N. asteroides. The other isolates were identified as Rhodococcuscoprophilus, R. equi, R. erythropolis, R. maris, Mycobacteriumfortuitum, and strains belonging to the genera Nocardia, Rhodococcus, Oerskovia, Amycolatopsis and Micromonospora. Distribution of actinomycetes in the samples varied. This observation appeared to indicate that plant design, operational and environmental conditions might play an important role in determining the types of actinomycetes in aeration basins.

Multi-Center Study of Thromboplastin Calibration Precision – Influence of Reagent Species, Composition, and International Sensitivity Index (ISI)

1993 ◽  
Vol 69 (01) ◽  
pp. 035-040 ◽  
Author(s):  
A M H P van den Besselaar ◽  
R M Bertina
Keyword(s):  
Oral Anticoagulants ◽  
International Normalized Ratio ◽  
The Other ◽  
World Health ◽  
Rabbit Brain ◽  
Sensitivity Index ◽  
Bovine Plasma ◽  
Significant Difference ◽  
The Mean ◽  
International Sensitivity Index

SummaryFour thromboplastin reagents were tested by 18 laboratories in Europe, North-America, and Australasia, according to a detailed protocol. One thromboplastin was the International Reference Preparation for ox brain thromboplastin combined with adsorbed bovine plasma (coded OBT/79), and the second was a certified reference material for rabbit brain thromboplastin, plain (coded CRM 149R). The other two thromboplastin reagents were another rabbit plain brain thromboplastin (RP) with a lower ISI than CRM 149R and a rabbit brain thromboplastin combined with adsorbed bovine plasma (RC). Calibration of the latter two reagents was performed according to methods recommended by the World Health Organization (W. H. O.).The purpose of this study was to answer the following questions: 1) Is the calibration of the RC reagent more precise against the bovine/combined (OBT/79) than against the rabbit/plain reagent (CRM 149R)? 2) Is the precision of calibration influenced by the magnitude of the International Sensitivity Index (ISI)?The lowest inter-laboratory variation of ISI was observed in the calibration of the rabbit/plain reagent (RP) against the other rabbit/plain reagent (CRM 149R) (CV 1.6%). The highest interlaboratory variation was obtained in the calibration of rabbit/plain (RP) against bovine/combined (OBT/79) (CV 5.1%). In the calibration of the rabbit/combined (RC) reagent, there was no difference in precision between OBT/79 (CV 4.3%) and CRM 149R (CV 4.2%). Furthermore, there was no significant difference in the precision of the ISI of RC obtained with CRM 149R (ISI = 1.343) and the rabbit/plain (RP) reagent with ISI = 1.14. In conclusion, the calibration of RC could be performed with similar precision with either OBT/79 or CRM 149R, or RP.The mean ISI values calculated with OBT/79 and CRM 149R were practically identical, indicating that there is no bias in the ISI of these reference preparations and that these reference preparations have been stable since their original calibration studies in 1979 and 1987, respectively.International Normalized Ratio (INR) equivalents were calculated for a lyophilized control plasma derived from patients treated with oral anticoagulants. There were small but significant differences in the mean INR equivalents between the bovine and rabbit thromboplastins. There were no differences in the interlaboratory variation of the INR equivalents, when the four thromboplastins were compared.

Prothrombin Time Standardization: Report of the Expert Panel on Oral Anticoagulant Control

1979 ◽  
Vol 42 (04) ◽  
pp. 1073-1114 ◽  
Keyword(s):  
Prothrombin Time ◽  
Expert Panel ◽  
The Other ◽  
Rabbit Brain ◽  
Calibration Constant ◽  
Freeze Dried ◽  
The Mean ◽  
Point Of Intersection ◽  
And Control ◽  
Standardization Report

SummaryIn collaborative experiments in 199 laboratories, nine commercial thromboplastins, four thromboplastins held by the National Institute for Biological Standards and Control (NIBS & C), London and the British Comparative Thromboplastin were tested on fresh normal and coumarin plasmas, and on three series of freeze-dried plasmas. One of these was made from coumarin plasmas and the other two were prepared from normal plasmas; in each series, one plasma was normal and the other two represented different degrees of coumarin defect.Each thromboplastin was calibrated against NIBS&C rabbit brain 70/178, from the slope of the line joining the origin to the point of intersection of the mean ratios of coumarin/normal prothrombin times when the ratios obtained with the two thromboplastins on the same fresh plasmas were plotted against each other. From previous evidence, the slopes were calculated which would have been obtained against the NIBS&C “research standard” thromboplastin 67/40, and termed the “calibration constant” of each thromboplastin. Values obtained from the freeze-dried coumarin plasmas gave generally similar results to those from fresh plasmas for all thromboplastins, whereas values from the artificial plasmas agreed with those from fresh plasmas only when similar thromboplastins were being compared.Taking into account the slopes of the calibration lines and the variation between laboratories, precision in obtaining a patient’s prothrombin time was similar for all thromboplastins.

Platelet Suruival and Function in Rats with Enhanced Thrombotic Tendency

1985 ◽  
Vol 54 (04) ◽  
pp. 739-743 ◽  
Author(s):  
Federica Delaini ◽  
Elisabetta Dejana ◽  
Ine Reyers ◽  
Elisa Vicenzi ◽  
Germana De Bellis Vitti ◽  
...  
Keyword(s):  
Arachidonic Acid ◽  
Nephrotic Syndrome ◽  
Platelet Function ◽  
Laboratory Tests ◽  
Thrombus Formation ◽  
The Other ◽  
Mean Survival Time ◽  
The Mean ◽  
And Function ◽  
Thrombotic Tendency

SummaryWe have investigated the relevance of some laboratory tests of platelet function in predicting conditions of thrombotic tendency. For this purpose, we studied platelet survival, platelet aggregation in response to different stimuli, TxB2 and 6-keto-PGFlα production in serum of rats bearing a nephrotic syndrome induced by adriamycin. These animals show a heavy predisposition to the development of both arterial and venous thrombosis. The mean survival time was normal in nephrotic rats in comparison to controls. As to aggregation tests, a lower aggregating response was found in ADR-treated rats using ADP or collagen as stimulating agents. With arachidonic acid (AA) we observed similar aggregating responses at lower A A concentrations, whereas at higher AA concentrations a significantly lower response was found in nephrotic rats, despite their higher TxB2 production. Also TxB2 and 6-keto-PGFlα levels in serum of nephrotic rats were significantly higher than in controls. No consistent differences were found in PGI2-activity generated by vessels of control or nephrotic rats.These data show that platelet function may appear normal or even impaired in rats with a markedly increased thrombotic tendency. On the other hand, the significance of high TxB2 levels in connection with mechanisms leading to thrombus formation remains a controversial issue.

Voronoi Analysis of a Soccer Game

2004 ◽  
Vol 9 (3) ◽  
pp. 233-240 ◽  
Author(s):  
S. Kim
Keyword(s):  
Collective Behavior ◽  
Quantitative Assessment ◽  
The Other ◽  
Analysis Method ◽  
Random System ◽  
Soccer Game ◽  
Voronoi Polygons ◽  
The Mean

This paper describes a Voronoi analysis method to analyze a soccer game. It is important for us to know the quantitative assessment of contribution done by a player or a team in the game as an individual or collective behavior. The mean numbers of vertices are reported to be 5–6, which is a little less than those of a perfect random system. Voronoi polygons areas can be used in evaluating the dominance of a team over the other. By introducing an excess Voronoi area, we can draw some fruitful results to appraise a player or a team rather quantitatively.

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