Mass balance analysis of triclosan, diethyltoluamide, crotamiton and carbamazepine in sewage treatment plants

2010 ◽  
Vol 61 (7) ◽  
pp. 1739-1747 ◽  
Author(s):  
N. Nakada ◽  
M. Yasojima ◽  
Y. Okayasu ◽  
K. Komori ◽  
Y. Suzuki
Keyword(s):  
Mass Balance ◽  
Water Distribution ◽  
Early Stage ◽  
Sewage Treatment ◽  
Distribution Coefficients ◽  
Water Soluble ◽  
Return Flow ◽  
Sewage Treatment Plants ◽  
Treatment Techniques ◽  
Water Soluble Drugs

The behavior of antibacterial triclosan, insect-repellent diethyltoluamide (DEET), anticonvulsant carbamazepine, and antipruritic crotamiton was investigated at two sewage treatment plants (STPs) to clarify their complete mass balance. Twenty-four-hour flow-proportional composite samples were collected from the influent and effluent of primary and final sedimentation tanks, a biofiltration tank and disinfection tanks. Sludge samples (i.e., activated and excess sludge) and samples of the return flow from the sludge treatment process were collected in the same manner. The analytes in both the dissolved and particulate phases were individually determined by a gas chromatograph equipped with mass spectrometer. Triclosan was dominantly detected in the particulate phase especially in the early stage of treatment (up to 83%) and was efficiently removed (over 90%) in STPs, mainly by sorption to sewage sludge. Limited removal was observed for DEET (55±24%), while no significant removal was demonstrated for crotamiton or carbamazepine. The solid-water distribution coefficients (Kd, n=4) for triclosan (log Kd: 3.7–5.1), DEET (1.3–1.9) and crotamiton (1.1–1.6) in the sludge samples are also determined in this study. These findings indicate the limitations of current sewage treatment techniques for the removal of these water-soluble drugs (i.e. DEET, carbamazepine, and crotamiton).

Extraction efficiency of phosphate from pre-coagulated sludge with NaHS

2006 ◽  
Vol 54 (5) ◽  
pp. 119-129 ◽  
Author(s):  
F. Kato ◽  
H. Kitakoji ◽  
K. Oshita ◽  
M. Takaoka ◽  
N. Takeda ◽  
...  
Keyword(s):  
Sewage Sludge ◽  
Mass Balance ◽  
Extraction Method ◽  
Extraction Efficiency ◽  
Sewage Treatment ◽  
Limited Resource ◽  
High Concentration ◽  
Sludge Treatment ◽  
Extraction Mechanism ◽  
Sewage Treatment Plants

The recovery of phosphorus from sewage and sludge treatment systems is particularly important because it is a limited resource and a large proportion of the phosphorus currently used in Japan must be imported. We have been experimentally evaluating recovery methods with sulphide. In this study, we focussed on the extraction of phosphate from the sludge, and sought to achieve a greater extraction efficiency and to validate the extraction mechanism. We conducted three experiments, i.e. a sludge-type experiment, a coagulant ratio of pre-coagulated sludge experiment, and a concentration of pre-coagulated sludge experiment. Phosphate was extracted not with normal sewage sludge but with pre-coagulated sludge and FePO4 reagent at S/Fe=1.0–2.0. A coagulant ratio of 23 mg Fe L−1 was required in the pre-coagulation process to effectively extract phosphate. A high concentration of pre-coagulated sludge was required for the phosphate extraction. The mass balance was calculated, and 44.0% of phosphorus was extracted to supernatant, and 98.5% of iron and 98.3% of sulphur (44.1% of sulphur was sulphide). Thus, phosphate can be selectively separated from iron by the phosphate extraction method with NaHS, and phosphorus and iron can be recovered and reused at sewage treatment plants using ferric chloride as a coagulant.

Calculation methods to perform mass balance of endocrine disrupting compounds in a submerged membrane bioreactor: fate and distribution of estrogens during the biological treatment

2011 ◽  
Vol 64 (11) ◽  
pp. 2158-2168 ◽  
Author(s):  
E. B. Estrada-Arriaga ◽  
P. Mijaylova
Keyword(s):  
Mass Balance ◽  
Water Distribution ◽  
Membrane Bioreactor ◽  
Dry Weight ◽  
Endocrine Disrupting Compounds ◽  
Distribution Coefficients ◽  
Operational Conditions ◽  
Submerged Membrane Bioreactor ◽  
Endocrine Disrupting ◽  
Adsorption Processes

The purpose of this paper is to report the study of the fate and distribution of three endocrine disrupting compounds (estrogens); Estrone (E1), 17β-estradiol (E2), and 17α-ethinylestradiol (EE2) in a laboratory scale submerged membrane bioreactor (SMBR). For this matter, both aqueous and solids phases were analyzed for the presence of E1, E2 and EE2. The outcome of this study was that three SMBRs showed enhanced elimination of estrogens in different operational conditions; the estrogen removal was close to 100% in SMBR. Additionally, E1, E2 and EE2 were detected in SMBR sludge at concentrations of up to 41.2, 37.3 and 36.9 ng g−1 dry weight, respectively. The estrogen removal in the SMBRs was directly influenced by a combination of simultaneous biodegradation–adsorption processes, indicating that the main removal mechanism of the estrogens in the SMBRs is the biodegradation process. The E1, E2 and EE2 were biologically degraded in the SMBR (87–100%). The sorption of estrogens onto activated sludge was from 2%. Therefore, a high potential for estrogen removal by biodegradation in the SMBR was observed, allowing less estrogen concentration in the dissolved phase available for the adsorption of these compounds onto biological flocs. Two different methods were carried out for mass balance calculations of estrogens in SMBR. For the first method, the measured data was used in both liquid and solid phases, whereas for the second one, it was in aqueous phase and solid–water distribution coefficients (Kd) value of E1, E2 and EE2. The purpose of these methodologies is to make easier the identification of the main mechanisms involved in the removal of E1, E2 and EE2 in a SMBR. Both methods can be applied in order to determine the mechanism, fate and distribution of estrogens in a SMBR.

Review of the Environmental Occurrence of Alkylphenols and Alkylphenol Ethoxylates

1999 ◽  
Vol 34 (1) ◽  
pp. 79-122 ◽  
Author(s):  
Donald T. Bennie
Keyword(s):  
Agricultural Soils ◽  
Degradation Products ◽  
Sewage Treatment ◽  
Aquatic Organisms ◽  
Water Soluble ◽  
Natural Environments ◽  
Limited Information ◽  
Alkylphenol Ethoxylates ◽  
Environmental Matrices ◽  
Sewage Treatment Plants

Abstract Alkylphenol ethoxylates and, in particular, nonylphenol ethoxylates have found many industrial, commercial, institutional and household uses in Canada. These nonionic surfactants are very efficient and cost effective. Their widespread use has led to the detection of the parent surfactants and their degradation products in various environmental matrices. Alkylphenol ethoxylates can be degraded aerobically and anaerobically in natural environments and sewage treatment plants.. The resulting degradation products are more persistent, more toxic, more lipophilic, less water soluble and more estrogenic than their parent compounds. This article reviews the occurrence of nonylphenol polyethoxylates and their degradation products as well as octylphenol poly-ethoxylates and their degradation products. There is limited information available about the concentrations of these substances in their original product formulations. The highest levels of the degradation products, especially nonylphenol, occur in the anaerobically digested sludge of sewage treatment plants. Sludge from these sewage treatment plants may be used as an amendment to agricultural soils. Various sewage treatment plants have wide ranges of discharged effluent concentrations of these compounds — some appear to be very efficient at removing alkylphenolics from their effluent stream. Little information is available about the fate of these substances in their receiving environment, and environmental concentrations and bioaccumulation factors of these contaminants in aquatic biota. More research is required on the uptake, persistence and bioaccumulation of alkylphenolic metabolites in fish, mussels and other aquatic organisms

Triterpene Saponin Glycosides Impact the Percutaneous Delivery of Water Soluble Drugs

2008 ◽  
Author(s):  
V. Prasad Shastri ◽  
Christopher Pino ◽  
Michael A. Scherer ◽  
Chenxia Monica. Guan
Keyword(s):  
Water Soluble ◽  
Triterpene Saponin ◽  
Water Soluble Drugs

Changes of microbial indices of water quality in the Vistula and Brda rivers as a result of sewage treatment plant operation

2008 ◽  
Vol 37 (2) ◽  
Author(s):  
Maciej Walczak
Keyword(s):  
Water Quality ◽  
Sewage Treatment ◽  
Sewage Treatment Plant ◽  
Treatment Plant ◽  
Sewage Treatment Plants ◽  
Plant Operation ◽  
Treated Sewage ◽  
Microbiological Parameters ◽  
Microbial Indices

Changes of microbial indices of water quality in the Vistula and Brda rivers as a result of sewage treatment plant operationThis paper reports the results of studies of microbiological changes in the water quality of the Vistula and Brda rivers after the opening of sewage treatment plants in Bydgoszcz. The study involved determining the microbiological parameters of water quality. Based on the results obtained, it was found that the quality of the water in both rivers had improved decidedly after the opening of the plants, although an increased number of individual groups of microorganisms was found at the treated sewage outlet from one of the plants.

Solid Dispersions: A Review

2014 ◽  
Vol 4 (2) ◽  
Author(s):  
Sumant Saini ◽  
Yashwant .
Keyword(s):  
Solid Dispersions ◽  
Physicochemical Characterization ◽  
Water Soluble ◽  
Absolute Minimum ◽  
Technology Transfers ◽  
Molecular Arrangement ◽  
Water Soluble Drugs ◽  
Carrier Solvent ◽  
Preparation Techniques ◽  
Selection Of

Solid dispersions are one of the most promising strategies to improve the oral bioavailability of poorly water soluble drugs. By reducing drug particle size to the absolute minimum, and hence improving drug wettability, bioavailability may be significantly improved. This article reviews the various preparation techniques for solid dispersion and compiles some of the recent technology transfers. The different types of solid dispersions based on the molecular arrangement have been highlighted. Some of the practical aspects to be considered for the preparation of solid dispersions, such as selection of carrier, solvent and methods of physicochemical characterization, along with an insight into the molecular arrangement of drugs in solid dispersions are also discussed. In this review, it is intended to discuss the recent advances related on the area of solid dispersions.

Sign in / Sign up

Export Citation Format

Share Document