scholarly journals Effect of Thermal Drying and Chemical Treatments with Wastes on Microbiological Contamination Indicators in Sewage Sludge

2020 ◽  
Vol 8 (3) ◽  
pp. 376 ◽  
Author(s):  
Andreia F. Santos ◽  
Cátia P. Santos ◽  
Ana M. Matos ◽  
Olga Cardoso ◽  
Margarida J. Quina
Keyword(s):  
Sewage Sludge ◽  
Wastewater Treatment Plants ◽  
Coal Fly Ash ◽  
Microbiological Contamination ◽  
Salmonella Spp ◽  
Positive Role ◽  
E Coli ◽  
Chemical Treatments ◽  
Green Liquor Dregs ◽  
Thermal Drying

This work aims to evaluate the microbiological contamination of sewage sludge (SS) collected in urban wastewater treatment plants (WWTP) from Portugal. Two types of SS were considered: urban mixed (UM) and from anaerobic digestion (AD). The two types of samples were characterized in relation to the main physical and chemical parameters, as well as the microbiological contamination (Escherichia coli and Salmonella spp). Then, sanitation tests were conducted through thermal drying and chemical treatments. Towards a circular economy, industrial alkaline wastes (green liquor dregs - GLD, lime mud, coal fly ash, eggshell) were tested as alternatives to lime. Only six out of nineteen samples complied with the legal limits for both microorganisms. However, drying at 130 °C sanitized selected samples below the E. coli limit, regardless of the initial moisture or contamination. Additionally, CaO (obtained from eggshell) led to the complete elimination of E. coli at any dosage studied (0.05–0.15 g/g SSwet basis). GLD evidenced the ability to reduce E. coli contamination at room temperature, but not enough to comply with the legal limit. In general, this work highlights the need to sanitize the SS before its application to the soil, and the positive role of some wastes on this goal.

scholarly journals Agro-ecological Characterization of Vermicomposted Sewage Sludge from Municipal and Poultry Enterprise Wastewater Treatment Plants

2021 ◽  
Vol 50 (8) ◽  
pp. 2167-2178
Author(s):  
Diyana Dermendzhieva ◽  
Toncho Dinev ◽  
Gergana Kostadinova ◽  
Georgi Petkov ◽  
Georgi Beev
Keyword(s):  
Wastewater Treatment ◽  
Sewage Sludge ◽  
Wastewater Treatment Plants ◽  
Poultry Meat ◽  
Plate Count ◽  
Lumbricus Rubellus ◽  
Microbiological Analysis ◽  
Salmonella Spp ◽  
E Coli

The purpose of this study was to make an agro-ecological characterization of vermicompost (VC) produced from sewage sludge (SS). As a substrate, SS from municipal and poultry meat processing enterprise wastewater treatment plants (MTP and PTP, respectively) was utilized. The substrates were vermicomposted by Red Californian earthworm (Lumbricus rubellus) for 120 days. For VC quality assessment, 19 physicochemical and 6 microbiological parameters were used. The evaluation of physicochemical parameters was done according to ISO standard methods and microbiological analysis-by plating 1 mL of sample dilutions on selective, chromogenic culture medium sheets. It was found that the vermicompost from MTP (VC-M) had higher levels of EC, mineral elements (N, P and K compounds in forms available to plants), heavy metals (Mn, Cu, Zn, Cr, Ni, Pb, Cd) and coliforms, and lower levels of pH, TOC, C/N ratio, Fe, total plate count (TPC), Enterobacteriaceae and Salmonella spp. counts compared to VC from PTP (VC-P). During the vermicomposting process, the substrates from both wastewater treatment plants (TPs) showed similar trends towards decrease in pH, TOC, N-NH4+, C/N ratio, TPC, coliforms, E. coli, Enterobacteriaceae and Salmonella spp. counts, whereas the opposite trends were established for EC, TKN, N-NO3-, TP, P2O5, TK, and K2O values. The vermicomposting had a negligible effect on heavy metal concentrations. In the final substrates E. coli were not detected, while the bacterial spore forms (Clostridium perfringens) were not eliminated. The final substrates cannot be used as fertilizers or soil amendments because of the presence of Salmonella spp. and C. perfringens over the permissible limits according to EU and Bulgarian regulations.

scholarly journals Effects of Chemical Treatments on Microflora Species on Eggshell and Hatchability of Broiler Eggs

2021 ◽  
Vol 37 (1) ◽  
pp. 25-33
Author(s):  
L. T. Egbeyale ◽  
S. S. Abiola ◽  
A. O. Fanimo ◽  
O. M. Sogunle ◽  
O. S. Sowande ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Proteus Mirabilis ◽  
Embryonic Mortality ◽  
Salmonella Spp ◽  
E Coli ◽  
Chemical Treatments ◽  
Weight Losses ◽  
Randomized Design ◽  
Egg Shell ◽  
Dominant Bacteria

This study was conducted to determine the effects of three disinfectants on the microbes and hatchabilty of broiler eggs. One hundred and ninety-two medium-sided hatchable broiler eggs were divided into four groups with three replications of sixteen eggs each. Each group of eggs was assigned to each of the following treatments; untreated, NaOCl, H2O2 and KMnO4:HCHO combination (1:2). The eggs were incubated for 21 days. Data were analyzed using one-way analysis of variance in a completely randomized design. The bacteria isolated were Escherichia coli (225-390cfu/ml), Pseudomonas aeruginosa (78-139cfu/ml), Staphylococcus aureus and Proteus mirabilis (210-268cfu/ml), Salmonella spp (258-313cfu/ml) and fungi (63-101cfu/ml). Significant (P<0.05) variation was observed in the population of the micrfloral species on the egg shell. Escherichia coli were the pre-dominant bacteria recovered from all the samples before treatment. Effects of disinfectants on the microorganisms varied significantly (P<0.05) with KMnO4 + formaldehyde combination having the highest (57.36) effect on Salmonella spp. Similar effect of NaOCI and H2O2 was observed on S. aureus and proteus mirabilis, E. coli, P. aeruginosa and fungi. Eggs treated with KMnO4  + formaldehyde combination had the least significant (P<0.05) incubation weight losses value (14.63), while eggs treated with H2O2 had the highest value (17.00%). The results further showed that hatchability, chick hatchinh weight and early embryonic mortality were not significantly (P<0.05) affected by the treatments unlike the late embryonic mortality which was significant (P<0.05). Although, KMnO4 + formaldehyde combination is commonly used in the hatchery, in this experiment NaOCI and H2O2 compared favourably with formaldehyde as hatching disinfectants without adversely affecting hatching potentials.

Risk evaluation for pathogenic bacteria and viruses in sewage sludge compost

2002 ◽  
Vol 46 (11-12) ◽  
pp. 325-330 ◽  
Author(s):  
T. Watanabe ◽  
D. Sano ◽  
T. Omura
Keyword(s):  
Sewage Sludge ◽  
Risk Evaluation ◽  
Pathogenic Bacteria ◽  
Agricultural Activities ◽  
Acceptable Risk ◽  
Salmonella Spp ◽  
Sludge Compost ◽  
E Coli ◽  
Infectious Risk ◽  
O 157

Composting can be regarded as the most available option for recycling of sewage sludge. However, the existence of pathogenic bacteria and viruses in the compost has been scarcely investigated until now. So there is little information on the infectious risk through agricultural activities or gardening in using the compost. In this study, several kinds of composts were investigated for detection of pathogenic bacteria (Salmonella spp. and Escherichia coli O 157) and enteric viruses. It was concluded from the result that these bacteria and viruses could not be detected in 1.0 g-wet of any kinds of composts. Infectious risks through agricultural activities or gardening were evaluated by Monte Carlo simulation in the case that the compost was polluted by Salmonella spp., E. coli O 157:117 and Poliovirus 1. Criteria satisfying the acceptable risk (less than 10−4 per year) for these pathogenic bacteria and virus in the compost were determined from the result of simulations. 1.0 [CFU or PFU/g-wet] was available as the criteria for E. coli O157 and Poliovirus 1 in the compost. On the other hand, the criterion for Salmonella spp. in the compost should be established on a lower concentration than 0.001 CFU/g-wet.

scholarly journals Microbial safety of air-dried and rewetted biosolids

2011 ◽  
Vol 9 (2) ◽  
pp. 403-414 ◽  
Author(s):  
Duncan A. Rouch ◽  
Tania Mondal ◽  
Sneha Pai ◽  
Florian Glauche ◽  
Vennessa A. Fleming ◽  
...  
Keyword(s):  
Sewage Sludge ◽  
Membrane Filtration ◽  
Wastewater Treatment Plants ◽  
Microbial Safety ◽  
Layered Plates ◽  
Air Drying ◽  
E Coli ◽  
Treated Sewage ◽  
The Usa ◽  
The Uk

To assess microbial safety of treated sewage sludge (biosolids), we examined the inactivation of microbial indicators for potential bacterial, viral and protozoan pathogens. The levels of indicators were determined throughout the air-drying and storage phases of anaerobically digested sewage sludge. Samples were collected from two wastewater treatment plants (WWTPs) in Victoria, Australia. Established methods were applied for analysis of bacteria and coliphages, based on membrane filtration and layered plates, respectively. In the pan drying phase, the prevalence of Escherichia coli was reduced by &gt;5 log10 compared with sludge entering the pan. Thus, after pan drying of 8-11 months at WWTP A and 15 months at WWTP B, the numbers of E. coli were reduced to below 102 cfu/g dry solids (DS). This level is acceptable for unrestricted use in agriculture in Australia (P1 treatment grade), the UK (enhanced treatment status) and the USA (Class A pathogen reduction). Coliphage numbers also decreased substantially during the air-drying phase, indicating that enteric viruses are also likely to be destroyed during this phase. Clostridium perfringens appeared to be an overly conservative indicator. Survival, but not regrowth, of E. coli or Salmonella was observed in rewetted biosolids (15–20% moisture content), after being seeded with these species, indicating a degree of safety of stored biosolids upon rewetting by rain.

Surveillance of Antibiotic Resistance Among Enterobacteriaceae Strains Isolated in an Infectious Diseases Hospital from Romania

2018 ◽  
Vol 69 (5) ◽  
pp. 1240-1243
Author(s):  
Manuela Arbune ◽  
Mioara Decusara ◽  
Luana Andreea Macovei ◽  
Aurelia Romila ◽  
Alina Viorica Iancu ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Infectious Diseases ◽  
Salmonella Spp ◽  
Resistance Level ◽  
E Coli ◽  
Bacterial Genus ◽  
Antibiotic Resistance Profile ◽  
Carbapenem Resistant ◽  
Invasive Infections ◽  
Klebsiella Spp

The aim of the present study was to characterize the antibiotic resistance profile of enterobacteriaceae strains isolated in Infectious Diseases Hospital Galati, Romania, during 2016, in order to guide the local antibiotic stewardship strategy. There are 597 biological samples with positive cultures for enterobacteriaceae, related to invasive and non-invasive infections. The main bacterial genus were E. coli 62%, Klebsiella spp 15%, Proteus spp 11% and Salmonella spp 6%. Over a half of isolated strains have one or more antibiotic resistance. The resistance level depends on bacterial genus, with highest level found among the rare isolates: Enterobacter spp, Citrobacter spp, Morganella spp and Serratia spp. The rate of MDR was 17.,6% for E. coli, 40.9% for Klebsiella spp and 50.7% for Proteus spp. while the rate of strains producing Extended Spectrum of Beta Lactamase are 7.2% for E. coli, 28.4% for Klebsiella spp and 12.3% for Proteus spp. The carbapenem resistant strains were found in 1.1% cases.

Production of fuels on the basis of sewage sludge through conditioning using high calorific value fractions

2008 ◽  
Vol 3 (1) ◽  
Author(s):  
Karl-Georg Schmelz ◽  
Anja Reipa ◽  
Hartmut Meyer
Keyword(s):  
Sewage Sludge ◽  
Wastewater Treatment Plants ◽  
Treatment Plant ◽  
Calorific Value ◽  
Fluidised Bed ◽  
Sludge Treatment ◽  
Heating Value ◽  
Fine Coal ◽  
Used Cars ◽  
Plastic Components

Emschergenossenschaft and Lippeverband operate 59 wastewater treatment plants which produce approx. 100,000 Mg TS of sewage sludge each year. Using sludge pressure pipelines, about 60 % of this sludge are transported to the central sludge treatment plant in Bottrop. The digested sludges are conditioned using fine coal and polymers and are dewatered using membrane filters. By adding coal, the heating value of the sludge is raised which enables autothermal combustion of the dewatered sludges in fluidised bed furnaces at the central sludge treatment plant. In order to replace coal, a fossil fuel, as conditioning agent, experiments were conducted using alternative materials with high heating values. The addition of shredder fluff agglomerates proved to be particularly successful. Shredder fluff agglomerates are a residue from the recycling of used cars and are generated in a multistage process (e.g. Volkswagen-SiCon Process) by separating the light shredder fraction (plastic components etc.) from the total shredder fluff. The fibrous material is outstandingly suitable for improving the dewaterability and for sufficiently raising the heating value of the dewatered sludge in order to enable autothermal combustion. Since first experiments showed very positive results, a full-scale long-term test-run will take place in 2007.

Sludge minimization by disintegration at different wastewater treatment plants

2008 ◽  
Vol 3 (1) ◽  
Author(s):  
Luchien Luning ◽  
Paul Roeleveld ◽  
Victor W.M. Claessen
Keyword(s):  
Organic Matter ◽  
Wastewater Treatment ◽  
Anaerobic Digestion ◽  
Sewage Sludge ◽  
New Technologies ◽  
Wastewater Treatment Plants ◽  
Treatment Plant ◽  
Biological Degradation ◽  
Ongoing Research ◽  
Sludge Minimization

In recent years new technologies have been developed to improve the biological degradation of sewage sludge by anaerobic digestion. The paper describes the results of a demonstration of ultrasonic disintegration on the Dutch Wastewater Treatment Plant (WWTP) Land van Cuijk. The effect on the degradation of organic matter is presented, together with the effect on the dewatering characteristics. Recommendations are presented for establishing research conditions in which the effect of sludge disintegration can be determined in a more direct way that is less sensitive to changing conditions in the operation of the WWTP. These recommendations have been implemented in the ongoing research in the Netherlands supported by the National Institute for wastewater research (STOWA).

Treatment and Quality of Sewage Sludge in Germany - Results of a Survey

2007 ◽  
Vol 2 (1) ◽  
Author(s):  
A. Meda ◽  
C. Schaum ◽  
M. Wagner ◽  
P. Cornel ◽  
A. Durth
Keyword(s):  
Sewage Sludge ◽  
Treatment Process ◽  
Wastewater Treatment Plants ◽  
Current Status ◽  
Sludge Treatment ◽  
Sewage Sludge Treatment ◽  
Treatment And Disposal ◽  
German Association ◽  
Entire Treatment

TIn 2004, the German Association for Wastewater, Water and Waste (DWA) carried out a survey about the current status of sewage sludge treatment and disposal in Germany. The study covered about one third of the wastewater treatment plants and about two thirds of the entire treatment capacity (expressed in population equivalents) in Germany. This provides an up-to-date and representative database. The paper presents the most important results regarding sludge treatment, process engineering, current disposal paths and sewage sludge quality.

scholarly journals Ultrafiltration Process in Disinfection and Advanced Treatment of Tertiary Treated Wastewater

Membranes ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 221
Author(s):  
Rafał Tytus Bray ◽  
Katarzyna Jankowska ◽  
Eliza Kulbat ◽  
Aneta Łuczkiewicz ◽  
Aleksandra Sokołowska
Keyword(s):  
Wastewater Treatment ◽  
Wastewater Treatment Plants ◽  
Microscopic Analysis ◽  
Fecal Coliforms ◽  
Treated Wastewater ◽  
Chemical Parameters ◽  
Virus Particles ◽  
E Coli ◽  
The One ◽  
Physical And Chemical

The paper presents the results of research on the use of ultrafiltration, using membranes of 200 and 400 kDa separation, for disinfection of municipal treated wastewater. The research was conducted on a fractional technical scale using real municipal treated wastewater from two large wastewater treatment plants treating most of the wastewater over the one-million polycentric Gdańsk agglomeration (1.2 million inhabitants). UF 200 kDa and UF 400 kDa processes enabled further improvement of the physical and chemical parameters of treated wastewater. Total phosphorus (to below 0.2 mg/L–UF 200 kDa, 0.13 mg/L–UF 400 kDa) and turbid substances (to below 0.2 mg/L, both membranes) were removed in the highest degree. COD was reduced efficiently (to below 25.6 mgO2/L–UF 200 kDa, 26.8 mgO2/L–UF 400 kDa), while total nitrogen was removed to a small extent (to 7.12 mg/L–UF 200 kDa and 5.7 mg/L–UF 400 kDa. Based on the reduction of indicator bacteria; fecal coliforms including E. coli (FC) and fecal enterococci (FE) it was found that the ultrafiltration is an effective method of disinfection. Not much indicator bacterial were observed in the permeate after processes (UF 200 kDa; FC—5 CFU/L; FE—1 CFU/L and UF 400 kDa; FC—70 CFU/L; FE—10 CFU/L. However, microscopic analysis of prokaryotic cells and virus particles showed their presence after the application of both membrane types; TCN 3.0 × 102 cells/mL–UF 200 kDa, 5.0 × 103 cells/mL–UF 400 kDa, VP 1.0 × 105/mL. The presence of potentially pathogenic, highly infectious virus particles means that ultrafiltration cannot be considered a sufficient disinfection method for treated wastewater diverted for reuse or discharged from high load wastewater treatment plants to recreational areas. For full microbiological safety it would be advisable to apply an additional disinfection method (e.g., ozonation).

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