scholarly journals The laminar/turbulent transition in a sludge pipeline

2012 ◽  
Vol 65 (4) ◽  
pp. 697-702 ◽  
Author(s):  
Nicky Eshtiaghi ◽  
Flora Markis ◽  
Paul Slatter
Keyword(s):  
Predictive Models ◽  
Suspended Solids ◽  
Wastewater Treatment Plants ◽  
Total Suspended Solids ◽  
High Concentration ◽  
Sludge Treatment ◽  
Turbulent Transition ◽  
Solids Concentration ◽  
Fluid Behaviour ◽  
Behaviour Changes

Globally, wastewater treatment plants are under pressure to handle high concentration sludge in a sludge treatment line. Unawareness of the non-Newtonian behaviour of the thickened sludge has the potential to cause unexpected problems when the fluid behaviour changes from turbulent to laminar flow. In this study, sludge apparent viscosity was plotted as a function of total suspended solids concentration (TSS) and shear rate. Then, the transition velocity based on several predictive models in the literature was determined. This analysis provides a practical basis for the prediction of the pipe flow behaviour of thickened sludge in troubleshooting and engineering design.

Uncertainties of spectral in situ measurements in wastewater using different calibration approaches

2006 ◽  
Vol 53 (12) ◽  
pp. 187-197 ◽  
Author(s):  
L. Rieger ◽  
G. Langergraber ◽  
H. Siegrist
Keyword(s):  
Suspended Solids ◽  
Wastewater Treatment Plants ◽  
Total Suspended Solids ◽  
Data Sets ◽  
Global Calibration ◽  
Nitrite Nitrogen ◽  
Calibration Methods ◽  
Using Data ◽  
Nitrate And Nitrite

Three calibration methods were applied to UV/VIS spectra recorded in the influent of six wastewater treatment plants (WWTPs) to measure total COD (CODtot), filtered COD (CODfil), nitrate and nitrite nitrogen (NOx-N) and total suspended solids (TSS). It could be shown that a calibration of the sensor using data sets from four Swiss WWTPs leads to an improvement of the precision in comparison to the global calibration provided by the manufacturer. A calibration to the specific wastewater matrix always improves the results and gives the highest accuracy. For CODtot a mean coefficient of variation CVx of 12.5% could be reached, whereas for NOx-N only weak results were achieved (average CVx=36%).

Performance of activated sludge diffusion for biological treatment of hydrogen sulphide gas emissions

2013 ◽  
Vol 68 (9) ◽  
pp. 1932-1939 ◽  
Author(s):  
Vera L. Barbosa ◽  
Richard M. Stuetz
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Hydrogen Sulphide ◽  
Biological Treatment ◽  
Suspended Solids ◽  
Wastewater Treatment Plants ◽  
Broad Application ◽  
H2s Removal ◽  
Treatment Performance ◽  
Solids Concentration

Odours from wastewater treatment plants are comprised of a mixture of various gases with hydrogen sulphide (H2S) often being the dominant constituent. Activated sludge diffusion (ASD) as a biotreatment system for odour abatement has been conducted for over 30 years but has limited broad application due to disagreement in the literature regarding the effect that ASD may have on wastewater treatment performance. The effects of continuous H2S diffusion at 25 ppmv, with weekly peaks of approximately 100 ppmv, on H2S removal efficiency and wastewater treatment performance was evaluated over a 2-month period using an activated sludge pilot plant. H2S removal averaged 100% during diffusion at 25 ppmv, and 98.9% during the 100 ppmv peak periods. A significant increase in mixed liquor volatile suspended solids concentration (P < 0.01) was observed during H2S diffusion, which may be due to an increase in H2S-degrading microorganisms. There was no adverse effect of H2S on nitrification throughout the ASD trials. Ammonia (NH3) removal was slightly better in the test receiving H2S diffusion (87.6%) than in the control (85.4%). H2S diffusion appeared to improve robustness of the AS biomass to operational upsets.

Increased performance of secondary clarifiers using dynamic distribution of minimum return sludge rates

2009 ◽  
Vol 60 (9) ◽  
pp. 2439-2445 ◽  
Author(s):  
A. Lynggaard-Jensen ◽  
P. Andreasen ◽  
F. Husum ◽  
M. Nygaard ◽  
J. Kaltoft ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Suspended Solids ◽  
Considerable Increase ◽  
Wastewater Treatment Plants ◽  
Treatment Plant ◽  
Total Flow ◽  
Equal Distribution ◽  
Solids Concentration ◽  
Hydraulic Load ◽  
And Control

Most wastewater treatment plants have several secondary clarifiers or even more sets of clarifiers including several secondary clarifiers, and in practice it is a well known problem that equal distribution of the load to the single clarifier (or set of clarifiers) is very difficult—not to say impossible—to obtain. If the problem is neglected, quite a big percentage of the total clarifier capacity—measured as the max. allowed hydraulic load—can be lost. Further, return sludge rates are seldom controlled by any other means than as a (typically too high) percentage of the inlet to the wastewater treatment plant—giving a varying and too low suspended solids concentration in the return sludge, which again can lead to an unnecessary use of polymer in the pre-dewatering of the surplus sludge taken from the return sludge. A control of the return sludge rate divided into two parts - control of the total return sludge flow and control of how the total flow shall be distributed between the secondary clarifiers - is able to solve the mentioned problems. Finally, as shall be demonstrated on full scale wastewater treatment plants, a considerable increase of the hydraulic capacity of the treatment plants can be obtained.

Spectral reflectance of suspended solid sediments: a laboratory experiment.

2020 ◽  
Author(s):  
Martina Carlino ◽  
Silvia Di Francesco
Keyword(s):  
Remote Sensing ◽  
Laboratory Experiment ◽  
Spectral Reflectance ◽  
Suspended Solids ◽  
Ocean Color ◽  
Total Suspended Solids ◽  
Reflectance Spectra ◽  
Optical Data ◽  
Band Selection ◽  
Solids Concentration

<p>Ocean color remote sensing proved to be a good alternative to traditional methods for total suspended solids concentration (TSS) monitoring purposes: numerous sensors have been developed for ocean color applications and different algorithms to retrieve TSS from remotely sensed data already exist.</p><p>Nevertheless, their application is generally limited by site-specific factors, and presently there is no uniform remote sensing model to estimate TSS.</p><p>The present study is focused in the development, evaluation and validation of different algorithms to estimate total suspended solids concentration based on laboratory reflectance data.</p><p>At this aim, a laboratory experiment was designed to collect the spectral reflectance of water containing fixed suspended particulate matter in terms of its concentration.</p><p>During the experiment, a total of 10 silty clay loam sediment samples were introduced into a tank filled with clear water up to a depth of 22 cm, illuminated by two 45 W lamps focused on center of water surface. After sieving, sediments were weighed so that TSS concentration ranging from 150 up to 2000 mg/L were obtained in the tank, being soil sediments suspension guaranteed by means of a mechanical pump-driven device.</p><p>Optical data were collected few minutes after each sediment introduction, using an Ocean Optics Jaz spectroradiometer mounted on a platform above the tank.</p><p>In accordance with previous studies, collected reflectance spectra of water containing sediments showed that, whatever is sediment concentration in water, reflectance in the red region is larger than that in the NIR region. Furthermore, reflectance spectra generally present two peaks: one between 550 nm and 750 nm, and the other between 750 nm and 850 nm, being the second peak insignificant for samples with very small TSS (e.g., SSC=150 mg/L), due to strong absorption of water.</p><p>After collection, laboratory reflectance spectra were integrated over the bandpass of different sensors’ selected bands, modulated by their relative response functions (RSR).</p><p>The basic principle of using a specific band, or band ratios to estimate a water parameter is to select spectral bands representative of its scattering/absorption features.</p><p>Band selection was achieved testing some previously formulated ocean color algorithms for the estimation of water quality parameters.</p><p>After band selection, linear regression model was applied to estimate the relationship between sensors’ reflectance at these bands and suspended solids concentration.</p><p>Results showed high correlation between selected sensors’ spectral red band and total suspended solids concentration higher than 500 mg/L up to 1360 mg/L, while less accuracy was observed for TSS concentrations higher than 1360 mg/L. Furthermore, the ratio between spectral red and green bands better estimates TSS in waters where total suspended concentration is not higher than 500 mg/L.</p><p> </p>

Reed beds: constructed wetlands for municipal wastewater treatment plant sludge dewatering

2001 ◽  
Vol 44 (11-12) ◽  
pp. 393-398 ◽  
Author(s):  
J.S. Begg ◽  
R.L. Lavigne ◽  
P.L.M. Veneman
Keyword(s):  
Wastewater Treatment ◽  
Total Phosphorus ◽  
Biochemical Oxygen Demand ◽  
Suspended Solids ◽  
Oxygen Demand ◽  
Total Suspended Solids ◽  
Sludge Dewatering ◽  
Sludge Treatment ◽  
Reed Beds ◽  
Reed Bed

Reed beds are an alternative technology wastewater treatment system that mimic the biogeochemical processes inherent in natural wetlands. The purpose of this project was to determine the effectiveness of a reed bed sludge treatment system (RBSTS) in southern New England after a six-year period of operation by examining the concentrations of selected metals in the reed bed sludge biomass and by determining the fate of solids and selected nutrients. Parameters assessed in both the reed bed influent and effluent: total suspended solids, biochemical oxygen demand, nitrate-nitrogen and total phosphorus. In addition, the following metals were studied in the reed bed influent, effluent and Phragmites plant tissue and the sludge core biomass: boron, cadmium, chromium, copper, iron, lead, manganese, molybdenum, nickel, and zinc. The removal efficiencies for sludge dewatering, total suspended solids and biochemical oxygen demand were all over 90%. Nitrate and total phosphorus removal rates were 90% and 80% respectively. Overall metals removal efficient was 87%. Copper was the only metal in the sludge biomass that exceeded the standards set by the Massachusetts Department of Environmental Protection for land disposal of sludge. The highest metal concentrations, for the most part, tended to be in the lower tier of the sludge profile. The exception was boron, which was more concentrated in the middle tier of the sludge profile. The data and results presented in this paper support the notion that reed bed sludge treatment systems and the use of reed beds provide an efficient and cost effective alternative for municipal sludge treatment.

scholarly journals Reliability of removal of selected pollutants in different technological solutions of household wastewater treatment plants

2017 ◽  
Vol 35 (1) ◽  
pp. 141-148 ◽  
Author(s):  
Michał Marzec
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Suspended Solids ◽  
Wastewater Treatment Plants ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Total Suspended Solids ◽  
Hybrid Reactor ◽  
Limit Values

AbstractThe reliability of removal of selected contaminants in three technological solutions of the household sewage treatment plants was analysed in this paper. The reliability of the sewage treatment plant with activated sludge, sprinkled biological deposit and hybrid reactor (activated sludge and immersed trickling filter) was analyzed. The analysis was performed using the Weibull method for basic indicators of impurities, BOD5, COD and total suspended solids. The technological reliability of the active sludge treatment plant was 70% for BOD5, 87% for COD and 66% for total suspended solids. In the sewage treatment plant with a biological deposit, the reliability values determined were: 30% (BOD5), 60% (COD) and 67% (total suspended solids). In a treatment plant with a hybrid reactor, 30% of the BOD5and COD limit values were exceeded, while 30% of the total suspended solids were exceeded. The reliability levels are significantly lower than the acceptable levels proposed in the literature, which means that the wastewater discharged from the analysed wastewater treatment plants often exceeds the limit values of indicators specified in currently valid in Poland Regulation of the Minister of Environment for object to 2000 population equivalent.

scholarly journals Efficiency of Sewage Treatment Plants in the Sequential Batch Reactor

2018 ◽  
Vol 28 (3) ◽  
pp. 121-131 ◽  
Author(s):  
Anita Jakubaszek ◽  
Artur Stadnik
Keyword(s):  
Wastewater Treatment ◽  
Total Nitrogen ◽  
Total Phosphorus ◽  
Suspended Solids ◽  
Wastewater Treatment Plants ◽  
Batch Reactor ◽  
Sewage Treatment ◽  
Total Suspended Solids ◽  
Sewage Treatment Plants ◽  
Sequential Batch Reactor

Abstract The article analyzes the effectiveness of individual Actibloc wastewater treatment plants (produced by Sotralentz) working in the technology of low-rate activated sludge in the Sequential Batch Reactor (SBR) system. The assessment of the effectiveness of household wastewater treatment plants was made on the basis of pollutants: BOD5, COD, total suspended solids, total nitrogen and total phosphorus. The research objects were four household sewage treatment plants located in: Lubań, Kłębanowice, Stara Rzeka and Kościan. The efficiency of removing pollutants in the examined facilities was in the range of: BOD5 92.2 ÷ 97.2%, COD 82.6 ÷ 89.9%, total suspended solids 90.2 ÷ 96.2%, total nitrogen 50.8 ÷ 83.1%, total phosphorus 46.5 ÷ 73.6%. The treated wastewater met the requirements set out in the Regulation of the Minister of the Environment on the conditions to be met when discharging sewage into water or soil, and on substances particularly harmful to the aquatic environment (Journal of Laws 2014, item 1800) in terms of indicators such as BOD5, COD, total suspended solids and total nitrogen. The effectiveness of phosphorus removal in the studied treatment plants was much lower.

scholarly journals KUALITAS PERAIRAN SUNGAI MUSI BAGIAN HILIR DITINJAU DARI KARAKTERISTIK FISIKA-KIMIA DAN STRUKTUR KOMUNITAS MAKROZOOBENTHOS

2017 ◽  
Vol 13 (3) ◽  
pp. 167
Author(s):  
Husnah Husnah ◽  
Eko Prianto ◽  
Siti Nurul Aida
Keyword(s):  
Water Quality ◽  
Organic Carbon ◽  
Dissolved Organic Carbon ◽  
Total Organic Carbon ◽  
Suspended Solids ◽  
Total Suspended Solids ◽  
Total Dissolved Solids ◽  
High Concentration ◽  
Dissolved Solids ◽  
Musi River

Sungai Musi merupakan sungai besar mengaliri wilayah Sumatera Selatan, Lampung, dan Bengkulu , dan bervariasi dalam pemanfaatannya, khususnya di bagian hilir, didominasi oleh kegiatan industri yang membuang limbahnya ke Sungai Musi. Kajian pengaruh industri terhadap Sungai Musi telah dilakukan, namun sebatas analisis fisik dan kimia lingkungan dan belum mengarah kepada pengaruhnya terhadap organisme air. Organisme air adalah indikator penting perubahan lingkungan karena organisme khususnya organisme dasar (benthos) menyimpan sejarah proses-proses terjadi di perairan. Riset yang bertujuan untuk mengetahui kualitas perairan Sungai Musi bagian hilir ditinjau dari karakteristik fisik dan kimia dan struktur makrozoobenthos telah dilakukan di Sungai Musi, Sumatera Selatan pada bulan Mei dan September 2006. Riset dilakukan bersifat survei lapangan. Delapan stasiun ditentukan di Sungai Musi bagian hilir berdasarkan pada perbedaan mikrohabitat. Stasiun riset masing masing antara lain Sejagung, Pulokerto, Jembatan Ampera, Sebokor, Pulau Burung, Upang, Pulau Payung, dan Sungsang. Pada masing masing stasiun, dilakukan pengambilan contoh air untuk parameter fisika, kimia, dan makrobenthos. Contoh air diambil dari atas perahu motor pada kedalaman 1,0 m dari permukaan air dengan menggunakan kemmerer water sampler. Sebagian contoh dianalisis di lapangan (suhu, pH, dan oksigen terlarut) dan sebagian lagi yaitu jumlah padatan tersesuspensi (total suspended solids), jumlah padatan terlarut (total dissolved solids), jumlah karbon organik (total organic carbon), organik karbon terlarut (dissolved organic carbon), konsumsi oksigen biologi (biochemical oxygen demand), nitrat, dan fosfat dianalisis di laboratorium kimia. Contoh makrozoobenthos diambil pada 10 titik di masing-masing stasiun, dengan menggunakan ekman dredge dengan bukaan mulut 400 cm2. Contoh makrobenthos pada masingmasing titik tersebut disortir dengan menggunakan saringan dan kemudian digabungkan (dikomposit) dan diawetkan dengan formalin 10%. Data kualitas air dianalisis dengan principle component analysis dan kelimpahan makrozoobenthos dianalisis dengan analisis cluster. Kualitas perairan di Sungai Musi bagian hilir dikelompokkan atas 2 yang mengalami tekanan berat yaitu dari Sejagung sampai dengan Pulau Burung dan tekanan ringan yaitu dari Upang sampai dengan Muara Sungai Musi. Kelompok pertama dicirikan oleh nilai konsentrasi total dissolved solids, total organic carbon, dan dissolved organic carbon yang tinggi diiringi dengan kelimpahan makrozoobenhthos yang rendah serta didominasi oleh Tubifex sp. Kelompok ke-2 dari Upang sampai dengan Muara Sungai Musi dicirikan oleh nilai konsentrasi total suspended solids yang tinggi, dengan kelimpahan makrozoobenthos yang tinggi dan didominasi oleh Gammarus. Musi River is a large river , crossing three provinces, South Sumatra, Lampung and Bengkulu, and differeing in types and levels of its resources ultization, particularly at the down stream of Musi River, mostly dominated by industries activities producing a waste which flows to the river. Several studies on the effect of industries on the Musi River have been conducted , however , limmieted on physical dan chemical aspects of the water, not yet to evaluate its effect on aquatic organism. Aquatic organism such macrozoobenthos is important indicator of environmental changes since this organism records the history of processes occurred in the water. Study to assess water quality of the down stream Musi River based on physical, chemical water characteristics and macrozoobenthos community structure was conducted at may and september 2006 in Musi River located in South Sumatera Province of Indonesia. The study used inventory field survey. Eight sampling sites; Sejagung, Pulokerto, Jembatan Ampera, Sebokor, Pulau Burung, Upang, Pulau Payung, and Sungsang were selected based on the microhabitat difference. water sampling for physical and chemical parameters and sediment, and  macrozoobenthos were carried in each sampling site. Water sample was collected at a depth of 1.0 m from the water surface by using kemmerer water sampler. Some water quality parameters such as temperature, pH, and dissolved oxygen) were directly analyzed in the field, while the others such as total suspended solids, total dissolved solids, total organic carbon, dissolved organic carbon, biochemical oxygen demand, nitrate, and phosphate were analyzed in laboratory. Macrozoobenthos was collected at ten sampling points in each sampling sites using Ekman Dredge of 400 cm2 mouth opening. Macrozoobenthos from ten sampling points was composited, sorted and preserved with formalin 10%. Water quality parameters were analyzed with principle component analysis while macrozoobenthos abundance was analyzed with cluster. Results revealed that water quality at the down stream Musi River was classified into two groups. The first group was the heavy degraded sites from Sejagung to Pulau Burung, characterized by having high concentration of total dissolved solids, total organic carbon, and dissolved organic carbon, low abundance of macrozoobenthos with Tubifex sp. as the dominant species. The second group was light degraded sites from Upang to the mouth of Musi River, characterized by high concentration of total suspended solids and high macrozoobenthos abundance with Gammarus sp. as the dominant species.

scholarly journals Comparative analysis of the quality of sewage discharged from selected agglomeration sewerage systems

2016 ◽  
Vol 30 (1) ◽  
pp. 35-42 ◽  
Author(s):  
Krzysztof Chmielowski ◽  
Piotr Bugajski ◽  
Grzegorz B. Kaczor
Keyword(s):  
Comparative Analysis ◽  
Total Nitrogen ◽  
Total Phosphorus ◽  
Suspended Solids ◽  
Wastewater Treatment Plants ◽  
Total Suspended Solids ◽  
Design Stage ◽  
Research Papers ◽  
Pollution Indicators

AbstractThe study provides a comparative analysis of the quality of sewage discharged from selected sewerage systems. The analyzed data were collected from 10 agglomeration sewerage systems discharging sewage into collective wastewater treatment plants (WTP). The investigated pollution indicators included BOD5, CODCr, total suspended solids and biogenic indicators such as total nitrogen and total phosphorus. These results were compared with the outcomes reported in commonly available research papers on sewage disposal. Considering the concentration of individual pollution indicators, more detailed categories of sewage pollution were adopted in this work. The sewage was divided into five basic groups: I – highly concentrated, II – concentrated, III – moderately concentrated, IV – diluted, and V – highly diluted. The sewage categories accounted for the following pollution indicators: BOD5, CODCr, total suspended solids, total phosphorus and total nitrogen. Mean BOD5, CODCr and total suspended solids in raw sewage were higher than average values reported in the referenced literature. Contrary to that, concentration of total phosphorus in raw sewage was significantly lower than reported by other authors. The outcomes of this study suggest that the predictions concerning pollution degree of raw sewage made at WTP design stage should not be based exclusively on general values provided in literature reports.

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