Obtaining Secondary Treatment with RBC/Underflow Clarifiers

1982 ◽  
Vol 14 (6-7) ◽  
pp. 429-442
Author(s):  
I L Bogert
Keyword(s):  
Treatment Process ◽  
High Rate ◽  
Experimental Program ◽  
Secondary Treatment ◽  
Lower Zone ◽  
Treatment Efficiency ◽  
Winter Conditions ◽  
Rotating Biological Contactors ◽  
One Year ◽  
The U.S

A one-year experimental program conducted at Edgewater, New Jersey, U.S.A. evaluated the concept of providing secondary treatment by the installation of rotating biological contactors (RBC's) in modified primary sedimentation tanks. A primary tank was divided horizontally into two zones separated by an intermediate floor. Four RBC's were placed in the upper zone. The lower zone provided secondary sedimentation. High rate primary sedimentation was provided to remove grit and trash without removing substantial portions of BOD and SS. The experimental program funded by the U.S. EPA and the Borough of Edgewater was conducted over a full year at different loads. The system proved to be an effective secondary treatment process with little difference in treatment efficiency between summer and winter conditions.

High-rate stormwater clarification with polymeric flocculant addition

2005 ◽  
Vol 51 (2) ◽  
pp. 79-88 ◽  
Author(s):  
J. Wood ◽  
C. He ◽  
Q. Rochfort ◽  
J. Marsalek ◽  
P. Seto ◽  
...  
Keyword(s):  
Treatment Process ◽  
Pilot Scale ◽  
High Rate ◽  
Surface Load ◽  
Stormwater Treatment ◽  
Storm Events ◽  
Treatment Efficiency ◽  
Treated Effluent ◽  
Inlet Zone ◽  
Runoff Events

Treatment of urban stormwater by clarification, with flocculant addition, was studied in Toronto, Canada using a pilot-scale clarifier with removable lamellar plates. Almost 90 stormwater runoff events were characterised at the study site and found fairly polluted. The previous research phase indicated good treatability of this stormwater by lamellar clarification with flocculant addition (total suspended solids, TSS, removal of 84%, at a surface load of 15 m/h), but there were concerns about cleaning plates after storm events. With the aid of numerical modelling, hydraulic improvements to the clarifier inlet zone were retrofitted in 2004 and permitted the removal of the lamellar pack without a loss in treatment efficiency. In the modified clarifier, a cationic polymeric flocculant dosage of 4 mg/L with conventional clarification provided a TSS removal of 77%, at surface loads up to 43 m/h. The use of the polymer did not increase the acute toxicity of the treated effluent. The clarifier sludge was severely polluted by several heavy metals and would require special disposal. The treatment process tested could be well applied in projects requiring intensive stormwater treatment at compact sites.

scholarly journals DISABILITY IN PRISON ACTIVITIES OF DAILY LIVING AND DEPRESSION IN OLDER PRISONERS: A PROSPECTIVE STUDY

2019 ◽  
Vol 3 (Supplement_1) ◽  
pp. S713-S713
Author(s):  
Lisa C Barry ◽  
Dorothy Wakefield ◽  
David C Steffens ◽  
Yeates Conwell
Keyword(s):  
Activities Of Daily Living ◽  
Prospective Study ◽  
Daily Living ◽  
Prison Population ◽  
High Rate ◽  
Older Prisoners ◽  
One Year ◽  
A Prospective Study ◽  
The U.S

Abstract The U.S. prison population is aging; more persons are being incarcerated in the second half of life and are aging “in place.” In the first prospective study to evaluate older prisoners’ mental health (Aging INSIDE), we determined if disability in activities of daily living specific to prison, prison activities of daily living (PADLs), predicts depression in this vulnerable population. To date, 134 older prisoners (age ≥50) sentenced at 9 Connecticut correctional facilities completed in-person interviews (baseline and one-year follow-up). A score of ≥10 on the 9-item Physician Health Questionnaire (PHQ-9) indicated depression. Participants were considered to have PADL disability if they reported any of the following as “very difficult” or “cannot do”: climbing on/off the top bunk (34%), cleaning their cell (5%), hearing orders (6%), walking while wearing handcuffs (33%) or shackles (34%), standing in line for medications (4%), and walking to chow (5%). Participants were mean age 57.0±6.6 years (range 50-79 years), racially diverse (43% White, 38% Black, 19% Hispanic/Other), 69 (50%) had PADL disability, and 35 (25%) were depressed at follow-up. Using logistic regression and controlling for gender, number of chronic conditions, lifetime suicide attempt, and baseline depression, baseline PADL disability was associated with depression one year later (OR = 3.41; 95%CI = 1.16, 9.97). As depression is a strong risk factor for subsequent suicide, and given the high rate of suicide among older prisoners in the U.S., these preliminary results indicate that PADL assessment may offer a simple means of identifying older prisoners at risk of depression.

Tennis- und Golfer-Ellenbogen

2015 ◽  
Vol 63 (4) ◽  
Keyword(s):  
Spontaneous Recovery ◽  
Clinical Symptoms ◽  
Lateral Epicondylitis ◽  
High Rate ◽  
Evidence Based ◽  
Physical Methods ◽  
Local Injections ◽  
One Year ◽  
Golfer’S Elbow ◽  
Non Surgical Treatment

“Tennis and golfer’s elbow” are common pathologies due to overload of forearm extensors and flexors, and actually occur mostly outside tennis and golf sports. Several differential diagnoses of medial and lateral epicondylitis have to be excluded as there are a number of other conditions with similar clinical symptoms. The high rate of spontaneous recovery has to be considered in treatment. Evidence based conservative treatment comprises excentric physiotherapy, local injections, and physical methods. Surgery is reserved for patients with persistence of symptoms for more than one year despite non-surgical treatment.

Usacerl's Experiences with Small Wastewater Treatment Plants in the USA

1990 ◽  
Vol 22 (3-4) ◽  
pp. 49-56
Author(s):  
E. D. Smith ◽  
R. J. Scholze
Keyword(s):  
Wastewater Treatment ◽  
Waste Treatment ◽  
Wastewater Treatment Plants ◽  
Remote Site ◽  
Corps Of Engineers ◽  
Military Installations ◽  
Recreation Areas ◽  
The Usa ◽  
Rotating Biological Contactors ◽  
The U.S

This paper presents a review of collected experience of one of the U.S. Corps of Engineers research laboratories in the area of small systems for wastewater treatment. Findings and experiences are presented for the use of package plants such as rotating biological contactors (RBCs), and remote site waste treatment at military installations and recreation areas.

The application of the root zone method for the treatment and reuse of high-strength abattoir waste in Mexico

1997 ◽  
Vol 35 (5) ◽  
pp. 271-278 ◽  
Author(s):  
Fermin Rivera ◽  
Alan Warren ◽  
Colin R. Curds ◽  
Esperanza Robles ◽  
Alejandro Gutierrez ◽  
...  
Keyword(s):  
Treatment Process ◽  
Root Zone ◽  
Ornamental Plants ◽  
High Strength ◽  
Faecal Coliforms ◽  
Treatment Efficiency ◽  
Zone Method ◽  
Stage System ◽  
Flow Through ◽  
Two Stages

A two-stage system for treating high-strength wastewater from an abattoir at Pachuca, Mexico is described. The system consists of an anaerobic digester followed by an artificially-constructed wetland which employs horizontal subsurface flow through the root zone of emergent hydrophytes planted in a gravel substrate. The main goals of this study were to monitor the treatment efficiency of the system for the first twelve months of operation and to assess the suitability of the effluent for irrigation purposes. The treatment efficiency during the twelve month period was generally good with mean removal efficiencies of 88.5% for BOD5, 87.4% COD, 89% suspended solids, 73.6% organic nitrogen and >99% faecal coliforms. Removal rates were generally poor for orthophosphates, NH3-nitrogen and NO3-nitrogen. The differing roles of the two stages in the treatment process are discussed. Although not suitable for irrigating crops, the effluent is being successfully used for the irrigation of ornamental plants and recreational lands.

scholarly journals One-year outcomes of the U.S. and Japanese regulatory trial of the Misago stent for treatment of superficial femoral artery disease (OSPREY study)

2016 ◽  
Vol 63 (2) ◽  
pp. 370-376.e1 ◽  
Author(s):  
Takao Ohki ◽  
John F. Angle ◽  
Hiroyoshi Yokoi ◽  
Michael R. Jaff ◽  
Jeffrey Popma ◽  
...  
Keyword(s):  
Femoral Artery ◽  
Superficial Femoral Artery ◽  
Artery Disease ◽  
One Year ◽  
The U.S

Occurrence and elimination of antibiotics at four sewage treatment plants in Japan and their effects on bacterial ammonia oxidation

2009 ◽  
Vol 59 (4) ◽  
pp. 779-786 ◽  
Author(s):  
Gopal Chandra Ghosh ◽  
Takashi Okuda ◽  
Naoyuki Yamashita ◽  
Hiroaki Tanaka
Keyword(s):  
Oxygen Uptake ◽  
Nalidixic Acid ◽  
Removal Efficiency ◽  
Treatment Process ◽  
Ammonia Oxidation ◽  
Oxygen Uptake Rate ◽  
Sewage Treatment ◽  
Secondary Treatment ◽  
Mixed Condition ◽  
Sewage Treatment Plants

The occurrence and elimination of seventeen antibiotics (three macrolides: azithromycin, clarithromycin and roxithromycin; five quinolones: ciprofloxacin, enrofloxacin, levofloxacin, nalidixic acid and norfloxacin; five sulfonamides: sulfadimethoxine, sulfadimizine, sulfamerazine, sulfamethoxazole and sulfamonomethoxine; and others: tetracycline, lincomycin, salinomycin and trimethoprim) were investigated at four full-scale sewage treatment plants in Japan. The highest concentration was recorded for clarithromycin (1,129 to 4,820 ng/L) in influent, followed by azithromycin (160 to 1,347 ng/L), levofloxacin (255 to 587 ng/L) and norfloxacin (155 to 486 ng/L). A vary inconsistence picture was obtained with negative to over 90% removal. Nalidixic acid (53 to100%) exhibited higher removal efficiency followed by norfloxacin (75 to 95%), levofloxacin (40 to 90%), ciprofloxacin (60 to 83%) and enrofloxacin (38 to 74%). Among macrolides, clarithromycin (50 to 88%) and azithromycin (34 to 86%) showed relatively higher removal efficiency than roxithromycin (−32 to 59%). For most of the antibiotics removal efficiency was higher in A2O and AO based secondary treatment process than CAS process. The effect of the antibiotics on bacterial ammonia oxidation determined by oxygen uptake rate presented that there was no significant effect below 0.05 mg/L of each antibiotics. Even at the same concentration, antibiotics in mixed condition had higher inhibition effects than individuals.

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