Tertiary filtration in small wastewater treatment plants

2007 ◽  
Vol 55 (7) ◽  
pp. 219-225 ◽  
Author(s):  
V. Naddeo ◽  
V. Belgiorno
Keyword(s):  
Particle Size ◽  
Wastewater Treatment ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Wastewater Treatment Plants ◽  
Rotating Disk ◽  
Quality Parameters ◽  
Particle Removal ◽  
Sand Filters ◽  
Filter Performance

Tertiary filtration can be proposed in small wastewater treatment plants with impact on protected water bodies. Rotating disk filters may be adopted, in respect to conventional sand filters, when low availability of space and low investment costs are the prevailing conditions. The overall objective of this research was to evaluate the filtration efficiency of rotating disk filters; to compare effectiveness with traditional sand filters; to analyse thoroughly the importance of particle size distribution in wastewater tertiary filtration. In the experimental activity, conventional wastewater quality parameters were investigated and particle size distribution (PSD) was characterized to discuss the filter effectiveness. The effect of design and operation parameters of tertiary filters were discussed related to particle removal curves derived from particles counts. Analysis of particle size distribution can be very useful to help comprehension of filtration processes, design of filtration treatments and to decide the best measures to improve filter performance.

Particle size analysis as a tool for performance measurements in high rate effluent filtration

2001 ◽  
Vol 43 (10) ◽  
pp. 303-311 ◽  
Author(s):  
J. H. J. M. van der Graaf ◽  
J. de Koning ◽  
J. Tang
Keyword(s):  
Particle Size ◽  
Wastewater Treatment ◽  
Membrane Filtration ◽  
Suspended Solids ◽  
Wastewater Treatment Plants ◽  
Treatment Plant ◽  
Size Analysis ◽  
Particle Removal ◽  
Deep Bed Filtration ◽  
Filter Performance

In the Netherlands almost all wastewater treatment plants have been redesigned and adapted in order to remove nitrogen, phosphorus and suspended solids to a very low level. The improved effluent quality leads to a growing interest in the reuse of effluent of the modernised wastewater treatment plants. This again results in investigations on filtration techniques as deep bed filtration and membrane filtration. At the wastewater treatment plant Ede research was done on deep bed filtration in order to develop relations between particle removal and filter performance and to explore ways of optimization. The results of the experiments are rather typical for effluent of modern Dutch wastewater treatment plants. The very low concentrations of suspended solids and precipitable substances result in poor flocculating properties. From turbidity measurements it may be concluded that the best results were obtained with a dosage of flocculant. However, the particle size measurements indicated the opposite. Suspended solids calculations, based on the particle volume distributions, showed a better removal without a dosage of flocculant. From this it is concluded that a dosage of coagulant (Fe3+ or Al3+) has an adverse effect on the removal efficiencies even at low dosages (1 mg/l).

The Influence of Biofilm Treatment Systems on Particle Size Distribution in Three Wastewater Treatment Plants

2010 ◽  
Vol 212 (1-4) ◽  
pp. 37-49 ◽  
Author(s):  
Juan José García-Mesa ◽  
José M. Poyatos ◽  
Fernando Delgado ◽  
Ernesto Hontoria
Keyword(s):  
Particle Size ◽  
Wastewater Treatment ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Wastewater Treatment Plants

Particle removal in different filtration systems for tertiary wastewater treatment - a comparison

1997 ◽  
Vol 36 (4) ◽  
pp. 259-267 ◽  
Author(s):  
Daniel Kobler ◽  
Markus Boller
Keyword(s):  
Particle Size ◽  
Wastewater Treatment ◽  
Particle Number ◽  
Quality Parameters ◽  
Particle Analysis ◽  
Particle Removal ◽  
Small Particles ◽  
Filter Performance ◽  
Filtration Step ◽  
Filter Particle

In seven wastewater installations in the area of Zürich, Switzerland, four different filtration systems for tertiary wastewater treatment (deep bed, cloth drum, continuous up-flow and cell filters) were investigated with special attention to particle size distributions in the in- and outflow of the flocculation and the filtration step. Flocculation and filter performance was characterised by the shift of particle number curves. For each filter, particle number, surface and volume removal as a function of particle size was determined and revealed to be an excellent tool to evaluate the filter plants under practical conditions. The number removal efficiency for small particles in the colloidal size range proved to be the most sensitive parameter and could be related to operating parameters such as flocculant dose and filtration rate. The results of the particle analysis were compared to quality parameters related to small particles such as micro-organism and heavy metal concentrations. A good agreement between the removal of small size particles (< 8 μm) and bacteria counts as well as copper was found in the different filter systems. The filters were finally classified according to their particle removal performance.

A Study of Particle Size Distribution from a Low Temperature Combustion Heavy-Duty Diesel Engine

2011 ◽  
Vol 130-134 ◽  
pp. 2379-2382
Author(s):  
Da Yu ◽  
Yi Qiang Pei ◽  
Suo Zhu Pan ◽  
Tong Li ◽  
Zhi Qiang Han ◽  
...  
Keyword(s):  
Particle Size ◽  
Diesel Engine ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Major Change ◽  
Quality Parameters ◽  
Injection Timing ◽  
Low Temperature Combustion ◽  
Heavy Duty Diesel ◽  
Engine Emission

The use of a variety of means of control in the engine combustion temperature in the low load has been more widely used. Although the opacity of the filter paper on smoke (FSN) was used as a standard in many laboratories PM quality parameters measured, but cannot be measured under different conditions the engine size and number of particles in a major change, especially in smaller size The particles on the human body more dangerous trends. So a study of particle size distribution of a heavy diesel engine emission was investigated under the condition of different intake valve closing timing, different EGR, different injection timing and multiple injections.

Cleanroom Mats: An Investigation of Particle Removal

1996 ◽  
Vol 39 (4) ◽  
pp. 19-27
Author(s):  
W. Whyte ◽  
T. Shields ◽  
T. Prvan
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Removal Efficiency ◽  
Adhesive Strength ◽  
Particle Removal ◽  
High Concentration ◽  
Low Concentration

The variables that influence the particle removal efficiency of cleanroom mats were investigated. The removal efficiency was generally found to be greater if the mat was of a softer type, the particles smaller, the particle size distribution more homogeneous, the distance between the particles greater, and the adhesive strength of the mat surface greater. One application of a mat surface was sufficient to remove a low concentration of similarly sized particles from a surface but it could require up to four mat surfaces to remove a high concentration of heterogeneously sized particles. It was found with heterogeneously sized particles that larger particles were removed first, thus allowing access to the smaller particles which could then be removed. If the mat was soft, it allowed larger particles to sink into it and smaller particles than normal to be picked up.

scholarly journals Changes in Particle Size Distribution in Hydroponic Lagoons Working as A Third Stage of Wastewater Treatment

2020 ◽  
Author(s):  
Aleksandra Bawiec ◽  
Katarzyna Pawęska ◽  
Krzysztof Pulikowski ◽  
Kinga Marek
Keyword(s):  
Particle Size ◽  
Wastewater Treatment ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Developed Surface ◽  
Third Stage ◽  
Summer Half ◽  
Wastewater Samples ◽  
Solids Removal ◽  
The Impact

Abstract The aim of research was to evaluate changes in the particle size distribution in two hydroponic lagoons working as a third stage of wastewater treatment where purification processes are based on plants and algae activity. Wastewater samples were taken during the winter and summer half of the year. In the samples taken from analyzed hydroponic lagoons the range of particles size was very wide (0.01 – 1000.0 μm). In both of the research facilities, the fractal dimension (Df) of particles was close to 2.0 what decides about developed surface of the particles. The results may indicate the predominance of algae cells in the total amount of suspensions. This information may pay a key role in determination the impact of discharged particles on the receiving water bodies quality as well as can be the main factor that allows to improve the system of suspended solids removal.

HEPA Filter Performance Under Adverse Conditions

2007 ◽  
Author(s):  
Michael Parsons ◽  
Kristina Hogancamp ◽  
Steven Alderman ◽  
Charles Waggoner
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
High Efficiency ◽  
Department Of Energy ◽  
Emission Rates ◽  
Filter Function ◽  
Filter Performance ◽  
The Media ◽  
Effect Of Particle Size

This study involved challenging nuclear grade high-efficiency particulate air (HEPA) filters under a variety of conditions that can arise in Department of Energy (DOE) applications such as: low or high RH, controlled and uncontrolled challenge, and filters with physically damaged media or seals (i.e., leaks). Reported findings correlate filter function as measured by traditional differential pressure techniques in comparison with simultaneous instrumental determination of up and down stream PM concentrations. Additionally, emission rates and failure signatures will be discussed for filters that have either failed or exceeded their usable lifetime. Significant findings from this effort include the use of thermocouples up and down stream of the filter housing to detect the presence of moisture. Also demonstrated in the moisture challenge series of tests is the effect of repeated wetting of the filter. This produces a phenomenon referred to as transient failure before the tensile strength of the media weakens to the point of physical failure. An evaluation of the effect of particle size distribution of the challenge aerosol on loading capacity of filters is also included. Results for soot and two size distributions of KCl are reported. Loading capacities for filters ranged from approximately 70 g of soot to nearly 900 g for the larger particle size distribution of KCl.

Particle size distribution and wastewater filter performance

1997 ◽  
Vol 36 (4) ◽  
pp. 217-224 ◽  
Author(s):  
Iris Kaminski ◽  
Nicolae Vescan ◽  
Avner Adin
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Power Law ◽  
Filter Performance ◽  
Natural Lakes ◽  
Size Groups ◽  
Filter Operation ◽  
Power Law Function ◽  
And Function

Particle size distribution (PSD) allows more accurate simulations of filtration models and better understanding of filter performance. PSD in municipal activated sludge effluent filtration is determined, varying filtration rate, grain size, flocculant type and dosage and function parameters are examined in this work. Results show, that removal efficiency varies for different size groups: small particles in the range of 5-10 μm in initialization stage, with no chemical aids, are poorly removed. Higher rate filters were more sensitive to the particle size than lower rate filters. Filtration with chemical aids is more sensitive to filtration conditions than filtration with no chemical additions. Particle size distribution in filtrate generally fits power law function behavior better than in raw effluent. The treatment smoothens the function somewhat. In a similar manner to the effect of settling in tanks or in natural lakes. Degree of correlation to power law function may indicate the mode of filter operation: high - working stage, low - breakthrough stage. β may also reflect on filters performance: high values - initial filtration stages. Decrease in β values - cycle progress towards breakthrough. Low β values, with low PSD correlation to power law function, may indicate low filtration efficiency or breakthrough.

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