Wyniki wyszukiwania - BazTech

1

Carbon and nutrient removal from domestic wastewaters in a modified 5-stage Bardenpho process via fuzzy modeling approach

Manav Demir Neslihan, Yildirim Asuman, Coskun Tamer, Balcik Canbolat Cigdem, Debik Eyup

Environment Protection Engineering

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2019

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Vol. 45, nr 1

5--16

EN

Gradual increase in the generation of wastewater results from the increasing global population. Thus, new treatment techniques and systems for controlling the treatment process depending on wastewater characteristics are desirable. This paper presents the use of a pilot-scale modified five-stage Bardenpho process with a 10 m3/day capacity for the treatment of real municipal wastewater. The process was developed for this study, and the steady-state removal efficiencies for COD (chemical oxygen demand), TKN (total Kjeldahl nitrogen), NH4+-N (ammonium nitrogen), PO43--P (phosphate phosphoms), SS (suspended solids), and VSS (volatile suspended solids) were 87±5%, 86±12%, 93±14%, 89±9%, 88±8%, 94±4%, and 94±4%, respectively. In the study, the effluent COD, TKN, and TP concentrations were also estimated using a fuzzy logic approach. The results showed that coefficients of determination are higher than 0.80 suggesting that the presented fuzzy logic approach may confidently be used for the estimation of the treatment performance.

2

Changes of the quality of activated sludge during the biological treatment of landfill leachate

Pieczykolan B., Płonka I., Kosel M.

Environment Protection Engineering

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2016

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Vol. 42, nr 3

33--42

EN

The effect of chemically pretreated landfill leachate on the properties of activated sludge has been investigated. The leachate was pretreated by a two-stage method consisting of coagulation and oxidation. The mixture of pretreated leachate (from 2.5 to 15 wt. %) and municipal wastewater was fed into a bioreactor. Results of the studies showed that the pretreated leachate contributed to the dispersion of the activated sludge flocs. As a result, a very low value of volume index (30 cm3gTS) and a significant turbidity of supernatant liquid were observed at the same time. The dispersion phenomenon was also confirmed by floc size distribution. An increase of the amount of small and very small flocs was observed.

3

Upgrading the effluent quality of an aerated lagoon with horizontal roughing filtration

Nabizadeh R., Naddafi K., Khazaei M., Fard R. F., Izanloo H., Yavari Z.

Environment Protection Engineering

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2015

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Vol. 41, nr 3

121--136

EN

Removal of suspended solids and microorganisms from an aerated lagoon effluent with a horizontal roughing filter (HRF) was investigated. The aerated lagoon receives Qom municipal wastewater. The HRF was operated at three filtration rates of 0.5, 1.0 and 1.5 m3/(m2·h) during four month operation period. The measured values of turbidity, TSS, COD, pH, temperature and flow rate of HRF at the former filtration rate were 79±12 NTU, 100±11 mg/dm3, 190±12 mg/dm3, 7±0.1 °C, 17±8 °C and 0.82 dm3/min, respectively. The differences between inlet and outlet values of pH and temperature were not significant (P > 0.05). Measures turbidity, TSS and COD in HRF final effluent were 15±13.7 NTU, 37±295 mg/dm3, 64±39.7 mg/dm3, respectively, which corresponds to 81.1%, 63% and 66.3% removal efficiencies, respectively. A decrease of removal efficiency was observed upon increasing filtration rates. The Spearman correlation coefficients between the head-loss and removal efficiencies ranged from 0.578 to 0.968 pointing to a direct relationship. Results of modeling approach revealed appropriate compliance between the values of the observed and predicted TSS for higher filtration rates.

4

Comparison of effectiveness of advanced treatment of municipal wastewater by sorption and nanofiltration. Separate processes and integrated systems

Bohdziewicz J., Kamińska G., Pawlyta M., Łukowiec D.

Environment Protection Engineering

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2015

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Vol. 41, nr 2

119--132

EN

The feasibility of effluent treatment in separate processes and in integrated systems has been compared. In the sorption process, carbon nanotubes were used in a pressure installation, enabling execution of the process of sorption with nanofiltration in a cross-flow system. Evaluation of treatment effects based on the measurement of typical pollution parameters (COD, TOC, phenolic index, forms of nitrogen and phosphorus) and concentration of bisphenol A. The results show poor feasibility of sorption as a process for advanced treatment of municipal effluent. Effluent polishing in integrated sorption-nanofiltration systems, however, guaranteed high removal rates of organic and inorganic pollutants.

5

Analiza jakościowa śladowych zanieczyszczeń organicznych w ściekach komunalnych z miast północno-wschodniej Polski

Kotowska U., Jasińska M.

Inżynieria i Ochrona Środowiska

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2011

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T. 14, nr 3

223-232

PL

W prezentowanej pracy przedstawiono wyniki analizy jakościowej śladowych zanieczyszczeń organicznych obecnych w surowych i oczyszczonych ściekach komunalnych z trzech miast północno-wschodniej Polski. Do izolacji analitów wykorzystano ekstrakcję do fazy stałej (SPE). Oznaczenia przeprowadzano techniką chromatografii gazowej sprzężonej ze spektrometrią mas (GC-MS). Identyfikację związków prowadzono w oparciu o dwa niezależne parametry widma mas oraz indeksy retencji. W badanych ściekach zidentyfikowano ponad 200 związków organicznych. Większość z nich to substancje wprowadzane do ścieków ze źródeł naturalnych: cyklu pokarmowego człowieka i rozkładu materii organicznej. Do substancji syntetycznych wykrytych w analizowanych próbkach należą m.in.: alkilobenzeny mezytylen i ksylen (składniki rozpuszczalników, olejów syntetycznych, smarów, mas bitumicznych), limonen i mentol (aromaty płynów do mycia naczyń i past do zębów), sole kwasu fosforowego i borowego (składniki czynne proszków do prania), ftalany, bezwodnik ftalowy, bisfenol A (stosowane w produkcji tworzyw sztucznych), paracetamol, naproksen, ibuprofen, karbamazepina (pozostałości leków). Dziesięć związków (fenol, 4-metylofenol, cykloheksan, p-ksylen, naftalen, benzaldehyd, ftalan dietylu, ftalan di-nbutylu, ftalan bis-(2-etyloheksylu), ftalan di-n-oktylu) wykrytych w ściekach uznawanych jest za szkodliwe dla środowiska i zdrowia człowieka. Substancje te znajdują się na listach priorytetowych zanieczyszczeń w USA i Unii Europejskiej. Potencjalnie szkodliwymi substancjami są także 2,6-ditertbutylo-p-krezol, kwas fosforowy oraz pozostałości farmaceutyków.

EN

Municipal wastewaters are outflows that come from households, offices, laundries, hospitals and small industrial plants. Also rain waters and snow-melt alongside with impurities washed away from streets access municipal wastewaters. Wastewaters are channelled to purification plants where they undergo processes which are designed to remove the excess of organic and inorganic matter and where their chemical analyses are carried out. Standard procedures used to mark organic compounds employed in wastewater treatment plants e.g.: biochemical and chemical oxygen demand allow to establish the total content of all, or certain group of, organic substances. The aim of presented work was the qualitative study of trace organic pollutants in municipal wastewater from three cities of north-eastern Poland. Identification of unknown organic compounds provides significant information about the composition of sewage and can be useful to maintain the suitable purity of surface waters. The procedure of qualitative analysis contains concentration of analytes on divinylbenzene (DVB) extraction disks and its subsequent eluting with organic solvents of different polarity: n-hexane, ethyl ether and methanol. Each eluate is directed to gas chromatography/mass spectrometry (GC/MS) separation and detection. Silylation of compounds eluted with ethyl ether and methanol were done prior to chromatographic analysis. For reliable identification of unknown organic compounds a combination of two independent parameters: mass spectra and retention indices were employed. More than 200 compounds were identified in municipal wastewater from the Wastewater Treatment Plants in Białystok, Łomża and Suwałki. This compounds belongs mainly to groups of aliphatic and aromatic acids, alcohols and phenols, carbonyl compounds and esters. The majority of detected compounds are natural substances, originating mainly in decomposition of remains of food and human excrements. Some substances (phenol, 4-methylphenol, cyclohexane, p-xylene, naphthalene, benzaldehyde, diethyl phthalate, di-n-butyl phthalate, di-n-octyl phthalate, bis-(2-ethylhexyl) phthalate) detected in wastewaters are known from their harmful influence on human health and natural environment and they are included in lists of priority and target pollutants in USA and European Union. Compounds potentially harmful for the environment found in analyzed municipal wastewaters are: 2,6-ditertbutylhydroxytoluene, phosphoric acid and drugs remnants: ibuprofen, naproxen, paracetamol, carbamazepine and caffeine.