scholarly journals Diversity of Iron Oxidizers in Groundwater-Fed Rapid Sand Filters: Evidence of Fe(II)-Dependent Growth by Curvibacter and Undibacterium spp.

2018 ◽  
Vol 9 ◽  
Author(s):  
Arda Gülay ◽  
Yağmur Çekiç ◽  
Sanin Musovic ◽  
Hans-Jørgen Albrechtsen ◽  
Barth F. Smets
Keyword(s):  
Sand Filters ◽  
Iron Oxidizers ◽  
Dependent Growth

Low-pressure membrane filtration with unconventional coagulation regimes

2005 ◽  
Vol 5 (5) ◽  
pp. 1-8 ◽  
Author(s):  
K.Y. Choi ◽  
B.A. Dempsey
Keyword(s):  
Activated Carbon ◽  
Membrane Filtration ◽  
Membrane Surface ◽  
Cross Flow ◽  
Chemical Cleaning ◽  
Sand Filters ◽  
Charge Neutralization ◽  
Floc Size ◽  
Filtration System ◽  
Pre Treatment

The objective of the research was to evaluate in-line coagulation to improve performance during ultrafiltration (UF). In-line coagulation means use of coagulants without removal of coagulated solids prior to UF. Performance was evaluated by removal of contaminants (water quality) and by resistance to filtration and recovery of flux after hydraulic or chemical cleaning (water production). We hypothesized that coagulation conditions inappropriate for conventional treatment, in particular under-dosing conditions that produce particles that neither settle nor are removed in rapid sand filters, would be effective for in-line coagulation prior to UF. A variety of pre-treatment processes for UF have been investigated including coagulation, powdered activated carbon (PAC) or granular activated carbon (GAC), adsorption on iron oxides or other pre-formed settleable solid phases, or ozonation. Coagulation pre-treatment is often used for removal of fouling substances prior to NF or RO. It has been reported that effective conventional coagulation conditions produced larger particles and this reduced fouling during membrane filtration by reducing adsorption in membrane pores, increasing cake porosity, and increasing transport of foulants away from the membrane surface. However, aggregates produced under sweep floc conditions were more compressible than for charge neutralization conditions, resulting in compaction when the membrane filtration system was pressurized. It was known that the coagulated suspension under either charge-neutralization or sweep floc condition showed similar steady-state flux under the cross-flow microfiltration mode. Another report on the concept of critical floc size suggested that flocs need to reach a certain critical size before MF, otherwise membranes can be irreversibly clogged by the coagulant solids. The authors were motivated to study the effect of various coagulation conditions on the performance of a membrane filtration system.

Denitrification of Sewage Effluents in Deep Bed Sand Filters

1993 ◽  
Vol 27 (5-6) ◽  
pp. 381-390 ◽  
Author(s):  
John Upton
Keyword(s):  
Waste Water ◽  
Pilot Study ◽  
Water Industry ◽  
Trickling Filter ◽  
Sand Filters ◽  
The United Kingdom ◽  
The Usa ◽  
Water Plants ◽  
The Cost ◽  
Pilot Plant Study

The European waste water industry will need to develop denitrification processes to remove nitrogen as pressures increase to reduce nutrient levels discharged in effluents. In the USA deep bed filter technology has been used extensively to provide denitrification to levels less than 5 mg/l TN. This paper describes this technology and the full scale performance at some waste water plants in Florida, USA. This paper also describes a pilot study in the United Kingdom at Severn Trent Water. The results of the pilot plant study indicate that denitrification in deep bed sand filters is a sound robust technology using methanol addition. Nitrogen removals greater than the 70% required in the EC Directive 1991 are possible at winter sewage temperatures. The process is most suitable for achieving nitrogen removal at trickling filter plants. The cost of methanol addition is calculated to be ₤10/1000m3.

Upgrading effluent quality for lagoon-based systems

1995 ◽  
Vol 31 (12) ◽  
pp. 379-387 ◽  
Author(s):  
Henryk Melcer ◽  
Brian Evans ◽  
Stephen G. Nutt ◽  
Anthony Ho
Keyword(s):  
Urban Communities ◽  
Ammonia Concentration ◽  
Sand Filters ◽  
Plant Operation ◽  
Capital Costs ◽  
Effluent Quality ◽  
Waste Sludge ◽  
Best Available Technology ◽  
Available Technology ◽  
Aeration Plant

To establish Best Available Technology Economically Achievable (BATEA) in non-urban communities which presently use conventional lagoon technology, an investigation was undertaken to evaluate alternatives which can be used to improve lagoon effluent and establish costs. Evaluated were the “Sutton” and the intermittent sand filtration or “New Hamburg” processes. The Sutton concept consists of a nitrifying extended-aeration plant followed by polishing lagoons, with waste sludge discharged into the lagoons. The New Hamburg concept consists of aerated or facultative lagoons, with the lagoon effluent sprayed intermittently over sand filters. The Sutton plants produce an improved effluent quality relative to conventional facultative lagoons in terms of BOD5 and TSS concentrations. Increases in ammonia concentration across the polishing pond occur after 5-7 years of plant operation, suggesting a need to implement a regular program of sludge removal from the lagoon. The New Hamburg process results in a significant improvement in effluent quality in terms of BOD5, TSS, TP, TKN, NH3-N and H2S concentrations. Approximate capital costs for upgrading the existing conventional lagoons in Ontario to Sutton and New Hamburg process facilities are estimated at US $221 million and US $93 million, respectively.

Up-flow roughing filtration: rehabilitation of a water treatment plant in Tarata, Bolivia

1998 ◽  
Vol 37 (9) ◽  
pp. 105-112 ◽  
Author(s):  
Ana María Ingallinella ◽  
Luis María Stecca ◽  
Martin Wegelin
Keyword(s):  
Water Treatment ◽  
Pilot Plant ◽  
Laboratory Tests ◽  
Treatment Plant ◽  
Water Treatment Plant ◽  
Horizontal Flow ◽  
Design Parameters ◽  
Sand Filters ◽  
Chemical Products ◽  
Made In

This paper presents the methodology used for the rehabilitation of the pretreatment stage in a water treatment plant for a village located in Bolivia which has 3500 inhabitants. The treatment plant was initially composed by horizontal-flow roughing filters and slow sand filters, but due to the high contents of colloidal turbidity of the providing source, it did not work properly. A plan of rehabilitation was made which comprised laboratory tests, pilot tests and proposal of modifications based on the results of previous stages. The laboratory tests were made in order to find the optimum conditions to coagulate the raw water. It was found that horizontal-flow roughing filters must be turned into up-flow roughing filters, so a pilot plant was built and was operated for three months in order to find suitable design parameters. The results obtained obtained during the operation of the pilot plant and the proposal of modifications are presented. The results of operation of the final plant, which are also reported, demonstrated the advantages of the up-flow roughing filtration as a pretreatment stage when it is necessary to add chemical products in small treatment plants.

scholarly journals Toxic Animal-Based Medicinal Materials Can Be Effective in Treating Endometriosis: A Scoping Review

Toxins ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 145
Author(s):  
Su-In Hwang ◽  
Young-Jin Yoon ◽  
Soo-Hyun Sung ◽  
Ki-Tae Ha ◽  
Jang-Kyung Park
Keyword(s):  
Side Effects ◽  
Clinical Studies ◽  
Malignant Tumors ◽  
Experimental Studies ◽  
Herbal Medicines ◽  
Treatment Method ◽  
Reproductive Age ◽  
Dependent Growth ◽  
Gynecological Disorder ◽  
Preclinical And Clinical Studies

Animal toxins and venoms have recently been developed as cancer treatments possessing tumor cell growth-inhibitory, antiangiogenesis, and proapoptotic effects. Endometriosis is a common benign gynecological disorder in reproductive-age women, and no definite treatment for this disorder is without severe side effects. As endometriosis and malignant tumors share similar characteristics (progressive, invasive, estrogen-dependent growth, and recurrence), animal toxins and venoms are thought to be effective against endometriosis. The objective of this study was to outline studies using toxic animal-based medicinal materials (TMM) as endometriosis treatment and to explore its clinical applicability. Preclinical and clinical studies using TMM were searched for in four databases from inception to October 2020. A total of 20 studies of TMM on endometriosis were included. In eight clinical studies, herbal medicines containing TMM were effective in relieving symptoms of endometriosis, with no side effects. In twelve experimental studies, the main therapeutic mechanisms of TMM against endometriosis were proapoptotic, antiangiogenesis, estrogen level-reducing, and possible anti-inflammatory effects. TMM are thus considered promising sources for the development of an effective treatment method for endometriosis. Further studies are needed to clarify the therapeutic mechanism of TMM against endometriosis and to provide sufficient grounds for clinical application.

Simulation of Cell Cycle Dependent Growth and Metabolism in Animal Cell Fermentation

1995 ◽  
Vol 28 (3) ◽  
pp. 326-329
Author(s):  
B. Szperalski ◽  
F. Geipel ◽  
U. Behrendt ◽  
J. Wahl
Keyword(s):  
Cell Cycle ◽  
Animal Cell ◽  
Dependent Growth ◽  
Cycle Dependent
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