scholarly journals Cost Effective Method for Toxicity Screening of Pharmaceutical Wastewater Containing Inorganic Salts and Harmful Organic Compounds

2019 ◽  
Vol 23 (1) ◽  
pp. 52-63 ◽  
Author(s):  
Elina Strade ◽  
Daina Kalnina
Keyword(s):  
Activated Sludge ◽  
Biological Treatment ◽  
Oxygen Demand ◽  
Cost Effective ◽  
Practical Implementation ◽  
Toxicity Screening ◽  
Pharmaceutical Wastewater ◽  
Cost Effective Method ◽  
Wide Range ◽  
Wastewater Biological Treatment

Abstract Pharmaceutical wastewater biological treatment plants are stressed with multi-component wastewater and unexpected variations in wastewater flow, composition and toxicity. To avoid operational problems and reduced wastewater treatment efficiency, accurate monitoring of influent toxicity on activated sludge microorganisms is essential. This paper outlines how to predict highly toxic streams, which should be avoided, using measurements of biochemical oxygen demand (BOD), if they are made in a wide range of initial concentration. The results indicated that wastewater containing multivalent Al3+ cations showed a strong toxic effect on activated sludge biocenosis irrespectively of dilutions, while toxicity of phenol and formaldehyde containing wastewater decreased considerably with increasing dilution. Activated sludge microorganisms were not sensitive to wastewater containing halogenated sodium salts (NaCl, NaF) and showed high treatment capacity of saline wastewater. Our findings confirm that combined indicators of contamination, such as chemical oxygen demand (COD), alone do not allow evaluating potential toxic influence of wastewater. Obtained results allow identifying key inhibitory substances in pharmaceutical wastewater and evaluating potential impact of new wastewater streams or increased loading on biological treatment system. Proposed method is sensitive and cost effective and has potential for practical implementation in multiproduct pharmaceutical wastewater biological treatment plants.

Savings with upgraded performance through improved activated sludge denitrification in the combined activated sludge–biofilter system of the Southpest Wastewater Treatment Plant

2008 ◽  
Vol 57 (8) ◽  
pp. 1287-1293 ◽  
Author(s):  
A. Jobbágy ◽  
G. M. Tardy ◽  
Gy. Palkó ◽  
A. Benáková ◽  
O. Krhutková ◽  
...  
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Wastewater Treatment Plant ◽  
Biological Treatment ◽  
Treatment Plant ◽  
Oxygen Demand ◽  
Process Efficiency ◽  
Initial Value ◽  
Initial Profile ◽  
Biological Treatment System

The purpose of the experiments was to increase the rate of activated sludge denitrification in the combined biological treatment system of the Southpest Wastewater Treatment Plant in order to gain savings in cost and energy and improve process efficiency. Initial profile measurements revealed excess denitrification capacity of the preclarified wastewater. As a consequence, flow of nitrification filter effluent recirculated to the anoxic activated sludge basins was increased from 23,000 m3 d−1 to 42,288 m3 d−1 at an average preclarified influent flow of 64,843 m3 d−1, Both simulation studies and microbiological investigations suggested that activated sludge nitrification, achieved despite the low SRT (2–3 days), was initiated by the backseeding from the nitrification filters and facilitated by the decreased oxygen demand of the influent organics used for denitrification. With the improved activated sludge denitrification, methanol demand could be decreased to about half of the initial value. With the increased efficiency of the activated sludge pre-denitrification, plant effluent COD levels decreased from 40–70 mg l−1 to < 30–45 mg l−1 due to the decreased likelihood of methanol overdosing in the denitrification filter

scholarly journals Isolation of two salt-tolerant strains from activated sludge and its COD degradation characteristics from saline organic wastewater

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Guizhong Zhou ◽  
Xitong Wang ◽  
Huiyang Zhao ◽  
Weiqian Zhang ◽  
Guishan Liu ◽  
...  
Keyword(s):  
Activated Sludge ◽  
Biological Treatment ◽  
Soluble Sugar ◽  
Oxygen Demand ◽  
Salt Tolerant ◽  
Bacterial Strains ◽  
Saline Wastewater ◽  
High Salt Stress ◽  
Relative Membrane Permeability ◽  
Organic Wastewater

Abstract The efficient biological treatment of saline wastewater has been limited by the low activities of microorganisms under saline conditions. High salinity poses unbalance osmotic stress across the cell wall and even leads to cell plasmolysis. In this work, we aim to isolate salt-tolerant bacterial strains from activated sludge, and apply them for degrading chemical oxygen demand (COD) of saline organic wastewater. Two salt-tolerant strains were screened and isolated from activated sludge, which was domesticated with salty water for over 300 days. The two strains were identified as Bacillus cereus (strain A) and Bacillus anthracis (strain B) through 16S rRNA sequencing. The degradation characteristics of strain A were explored. The results showed the relative membrane permeability of strain A remained stable under high salt stress, which glycine and proline play an important role to maintain cell osmotic. The protein and soluble sugar amounts of strain were increased by higher salt concentrations. In simulating saline wastewater, the optimum culture temperature, pH, salinity, influent COD concentration and inoculation amount of strain A were 35 °C, 9, 4%, 8000 mg L−1, 6%, respectively. Optimal conditions could provide guidance for the treatment of practical saline wastewater. The linear regression model of each impact factor built based on the result PB experiment revealed that cross-linking time has the most significant influence on COD removal for salt-tolerant strains. It will provide theoretical basis for biological treatment of saline organic wastewater.

Low temperature microwave and conventional heating pre-treatments to improve sludge anaerobic biodegradability

2013 ◽  
Vol 69 (3) ◽  
pp. 518-524 ◽  
Author(s):  
P. Vergine ◽  
J. Zábranská ◽  
R. Canziani
Keyword(s):  
Low Temperature ◽  
Activated Sludge ◽  
Oxygen Demand ◽  
Cost Effective ◽  
Conventional Heating ◽  
Waste Activated Sludge ◽  
Experimental Conditions ◽  
Primary Sludge ◽  
Batch Tests ◽  
Pre Treatment

This paper presents the results of lab-scale experiments on low temperature thermal pre-treatment (less than 100 °C) prior to anaerobic digestion of sewage sludge. Two heating ways, microwave heating (MH) and conventional heating (CH), and two types of sludge, primary and waste activated sludge, were compared under the same experimental conditions. The degree of solubilisation produced by MH and CH up to 72, 82 and 93 °C was firstly estimated. For both types of heating, increase in soluble chemical oxygen demand (COD) caused by the pre-treatment was about 14% on waste activated sludge and only 3% on primary sludge. The final temperature of 72 °C resulted as the most cost-effective in terms of additional soluble COD per unit of energy required. Subsequently, five series of biochemical methane potential mesophilic assays were run in 120 mL serum bottles on sludge samples pre-treated at 72 °C. When compared with control reaction vessels, no significant differences were noticed in net methane production of pre-treated primary sludge, whereas a relevant increase occurred regarding the pre-treated waste activated sludge. It was also observed that the trend of methane content in biogas during the batch tests can be described by a second order polynomial.

Practical experience with full-scale structured sheet media (SSM) integrated fixed-film activated sludge (IFAS) systems for nitrification

2014 ◽  
Vol 71 (4) ◽  
pp. 545-552 ◽  
Author(s):  
Hua Li ◽  
Jia Zhu ◽  
James J Flamming ◽  
Jack O'Connell ◽  
Michael Shrader
Keyword(s):  
Activated Sludge ◽  
Wastewater Treatment Plants ◽  
Contact Process ◽  
Plug Flow ◽  
Oxygen Demand ◽  
Cost Effective ◽  
Practical Experience ◽  
Full Scale ◽  
Fixed Film ◽  
The Usa

Many wastewater treatment plants in the USA, which were originally designed as secondary treatment systems with no or partial nitrification requirements, are facing increased flows, loads, and more stringent ammonia discharge limits. Plant expansion is often not cost-effective due to either high construction costs or lack of land. Under these circumstances, integrated fixed-film activated sludge (IFAS) systems using both suspended growth and biofilms that grow attached to a fixed plastic structured sheet media are found to be a viable solution for solving the challenges. Multiple plants have been retrofitted with such IFAS systems in the past few years. The system has proven to be efficient and reliable in achieving not only consistent nitrification, but also enhanced bio-chemical oxygen demand removal and sludge settling characteristics. This paper presents long-term practical experiences with the IFAS system design, operation and maintenance, and performance for three full-scale plants with distinct processes; that is, a trickling filter/solids contact process, a conventional plug flow activated sludge process and an extended aeration process.

ACTIVATED SLUDGE DIFFUSION FOR COST EFFECTIVE BIOLOGICAL TREATMENT OF ODORS FROM WASTEWATER TREATMENT WORKS

2002 ◽  
Vol 2002 (5) ◽  
pp. 765-787 ◽  
Author(s):  
Vera L. Barbosa ◽  
Adam W. R. Brookes ◽  
Suzy Morton ◽  
Joanna E. Burgess ◽  
Richard M. Stuetz
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Biological Treatment ◽  
Cost Effective

scholarly journals Diagnostic optical sequencing

2019 ◽  
Author(s):  
Lee E. Korshoj ◽  
Prashant Nagpal
Keyword(s):  
Single Molecule ◽  
Point Of Care ◽  
Cost Effective ◽  
Diagnostic Methods ◽  
Sequencing Platform ◽  
Molecular Variants ◽  
Cost Effective Method ◽  
Wide Range ◽  
Lactamase Gene ◽  
Modified Nucleobases

AbstractAdvances in precision medicine require high-throughput, inexpensive, point-of-care diagnostic methods with multi-omics capability for detecting a wide range of biomolecules and their molecular variants. Optical techniques have offered many promising advances towards such diagnostics. However, the inability to squeeze light with several hundred-nanometer wavelengths into angstrom-scale volume for single nucleotide measurements has hindered further progress. Recently, a block optical sequencing (BOS) method has been shown for determining relative nucleobase content in DNA k-mer blocks with Raman spectroscopy, and a block optical content scoring (BOCS) algorithm was developed for robust content-based genetic biomarker database searching. Here, we performed BOS measurements on positively-charged silver nanoparticles to achieve 93.3% accuracy for predicting nucleobase content in DNA k-mer blocks (where k=10), as well as measurements on RNA and chemically-modified nucleobases for extensions to transcriptomic and epigenetic studies. Our high-accuracy BOS measurements were then used with BOCS to correctly identify a β-lactamase gene from the MEGARes antibiotic resistance database and confirm the Pseudomonas aeruginosa pathogen of origin from <12 content measurements (<15% coverage) of the gene. These results prove the integration of BOS/BOCS as a diagnostic optical sequencing platform. With the versatile range of available plasmonic substrates offering simple data acquisition, varying resolution (single-molecule to ensemble), and multiplexing, this optical sequencing platform has potential as the rapid, cost-effective method needed for broad-spectrum biomarker detection.

Denitrificiation in a Non-Nitrifying Activated Sludge System

1992 ◽  
Vol 26 (5-6) ◽  
pp. 1097-1104 ◽  
Author(s):  
A. Lyngå ◽  
P. Balmér
Keyword(s):  
Organic Matter ◽  
Activated Sludge ◽  
Nitrogen Removal ◽  
Cost Effective ◽  
Pilot Scale ◽  
Anoxic Zone ◽  
Sludge Treatment ◽  
Activated Sludge System ◽  
Cost Effective Method ◽  
Nitrate Supply

Post-nitrification and recycling of the nitrified effluent to an anoxic zone in an activated sludge system for denitrification is proposed as a potentially cost-effective method for nitrogen removal in existing activated sludge treatment plants. Denitrification in a non-nitrifying activated sludge system with a SRT of 3-4 days has been studied in pilot scale. The results show that denitrification rates of at least 10 g N03-N/(kgVSS h) can be achieved. At COD/NO3-N ratios above 15, nitrate supply appears to control the denitrification rate while at COD/NO3-N ratios below 15 the rate appears to be controlled by the supply of easily biodegradable organic matter.

A Practical Access to Functionalized Alkyl Sulfinates

Synlett ◽  
2018 ◽  
Vol 29 (12) ◽  
pp. 1622-1626
Author(s):  
M. Haddad ◽  
P. Phansavath ◽  
V. Ratovelomanana-Vidal ◽  
C. Tran ◽  
B. Flamme ◽  
...  
Keyword(s):  
Functional Groups ◽  
Cost Effective ◽  
Good Tolerance ◽  
Mild Conditions ◽  
Cost Effective Method ◽  
Wide Range

We describe herein a three-step synthesis of aliphatic sulfinates. This cost-effective method involves the use of 2-mercaptobenzothiazole under mild conditions and exhibits good yields (up to 78% over three steps). This approach provides an access to a wide range of functionalized sulfinates. A good tolerance with respect to diverse functional groups (alkene, alkyne, ether, acetal) was also noted.

scholarly journals A SIMPLE CO2 EXTRACTION METHOD FOR RADIOCARBON ANALYSES OF DISSOLVED INORGANIC CARBON IN WATER SAMPLES WITHOUT A CARRIER GAS

Radiocarbon ◽  
2021 ◽  
pp. 1-15
Author(s):  
Hiroshi A Takahashi ◽  
Hiroko Handa ◽  
Masayo Minami
Keyword(s):  
Water Samples ◽  
Extraction Method ◽  
Inorganic Carbon ◽  
Dissolved Inorganic Carbon ◽  
Cost Effective ◽  
Carrier Gas ◽  
Vacuum Line ◽  
Cost Effective Method ◽  
Wide Range ◽  
Cryogenic Trapping

ABSTRACT We developed a simple and cost-effective method for extracting carbon from dissolved inorganic carbon (DIC) in water samples without a carrier gas. This method only slightly modifies the existing vacuum line for CO2 purification in radiocarbon research laboratories by connecting several reservoirs and traps. The procedure consists of repeated cycles of CO2 extraction from water into the headspace of the reaction container, expansion of the extracted gas into the vacuum line, and cryogenic trapping of CO2. High CO2 yield (∼98%) was obtained from a variety of water samples with a wide range of DIC concentrations (0.4–100 mmol·L−1, in the case of 1.2 mgC). The δ13C fractionation depended on the CO2 yield, while the 14C concentration was constant within the error range, regardless of the CO2 yield. The average δ13C discrepancy between the results of this method and direct analyses made using the GC-IRMS was 0.02 ± 0.06‰. The standard deviations (1σ) in fraction of modern carbon (F14C) ranged from 0.0002 to 0.0004 for waters below 0.01 of F14C, and below 0.8% of F14C values for waters above 0.1. We conclude that this method is useful for effectively extracting CO2 from DIC in water and yields accurate 14C data.

Sign in / Sign up

Export Citation Format

Share Document