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Distillation Cleanup Preceded GC Determination of Short-Chain Monocarboxylic Acids in Aqueous and Solid Samples of Wastewater Origin

Short-chain monocarboxylic acids (SCMAs) (C2-C5) formed in the process of aerobic biodegradation of larger organic molecules should often be monitored to optimize wastewater biological treatment and study the processes of converting organic waste matter into methane, etc. Gas chromatography (GC) seems a method of choice for such a task. Majority of samples require clean up before they can be injected into GC system. In this work a special refluxing apparatus is applied to concentrate and clean up the troublesome environment samples before injection into GC. To optimize separation of SCMAs in aqueous sample a special arrangement of two capillary columns, of very different polarity was used. The operational parameters of sample preparation were optimized and enrichment factors determined. The procedure developed was applied to determine SCMAs in troublesome aqueous and solid samples of wastewater treatment origin.

Effectiveness of Removal of Humic Substances and Heavy Metals from Landfill Leachates During their Pretreatment Process in the SBR Reactor

In the paper the removal efficiency of heavy metals as well as humic compounds, in the treatment of leachate mixed with municipal waste in a sequencing batch reactor was studied. Also, the accumulation of those metals in the activated sludge was examined. It has been shown that the removal efficiency of contamination with humic compounds, for Bx ranging from 0.23 to 0.45 mg COD mg-1 d.m. can reach 71÷74%. An increase in the concentrations of heavy metals in the activated sludge was recorded for Bx in the range 0.23÷1.64 mg COD mg-1 d.m. The amount of heavy metals in the effluent of the SBR in carrying out the process at Bx = 0.23÷0.96 mg COD mg-1 d.m. does not limit their discharge into water and sewer system.

Abstract

This paper presents the results of the research conducted on the installation designed for physico-chemical pretreatment of technological wastewater in the volume of up to 5.0 m3/day discharged from the production of protective and decorative coating materials used for wooden surfaces. The subject-matter installation constructed on a mobile pallet, consisted of a storage-averaging tank where concentrations were equalised with the use of circulation aeration and mixing. A variant, preliminary pre-oxidation with the use of hydrogen peroxide was conducted in this tank. A substantial installation set for the wastewater treatment plant consisted of two preliminary tube reactors, one cylindrical-conical processing reactor, stations for preparing and dispensing reagents and the sediment dewatering station. Considerable reductions in main chemical indicators of water pollution were obtained in the installation: both total suspended solids (TSS) and ether extract (EE) - more than 98%, chemical oxygen demand (COD) - 46-54%, biochemical oxygen demand (BOD5) - 39-46%, and free formaldehyde (HCHO) - 14-27% due to the use of pre-oxidation and the acid - alkaine double coagulation by applying the ALCAT 105 - SAX 25 system. The use of pre-oxidation with hydrogen peroxide in doses 250.0-450.0 mg/l and then two-stage coagulation resulted in an increase in the reduction of: COD and BOD5 by ca 10-15%, and HCHO by ca 58-66% with reference to the water pretreatment without pre-oxidation. The assessment of sediments formed during the process of pretreatment was made determining the leachable forms of metals (Cu, Ni and Ti) according to methodology of TCLP in compliance with the US EPA Method 1311.

Abstract

Vegetables are important source of nutrients for human body. Wastewater irrigation may lead to contamination of these vegetables and cause possible health risk. In the present study impact of waste water irrigation on metals uptake (Fe, Mn, Ni, Co, Zn, Cd, Cr and Pb) by five commonly consumed vegetables (radish, cabbage, lettuce, cauliflower and spinach) grown in the suburbs of Peshawar were investigated using AAS (Atomic Absorption spectrophotometer). The uptake and accumulation of metals for vegetables irrigated with wastewater were significantly (p < 0.05) higher than tube well irrigated vegetables and permissible limits of WHO/FAO. Among the edible parts of vegetables maximum accumulation of Mn, Pb and Cd occurred in radish followed by Ni and Fe in spinach while Cr and Zn were high in cauliflower and cabbage. The estimated daily intake of metals (DIM) revealed that at present the consumption of studied vegetables were under the tolerable limits of (US-EPA, IRIS), however intake of metals in waste water irrigated vegetables were significantly high and can cause health hazards in the long run

Abstract

The paper presents results of research concerning operating of five small wastewater treatment plants working in two different technologies: hydrobotanical wastewater treatment plant and constructed wetland. Each object was designed for the treatment of domestic sewage after preliminary mechanical treatment in a septic tank. Hydrobotanical wastewater treatment plants and one of constructed wetland beds were built for treating sewage produced in educational institutions and resort. In the article attention is paid to possibility of exceeding the maximum allowable concentration of pollutants for three main indicators of pollution: BOD5, COD, and total suspension. The reduction of these indices is required by the Regulation of the Minister of Environment [14] for wastewater treatment plants with PE < 2000. In addition, the paper presents the effects of wastewater treatment to reduce biogens. The best quality of outflow was reached by outflows from constructed wetland treatment plants. None of the observed objects fulfilled the requirements in terms of allowable concentrations for total suspension. The most effective were objects operating in technology of “constructed wetland”.

Abstract

A number of inorganic anions and metals, especially heavy metals, at certain conditions, have been found in potentially harmful concentrations in numerous water sources. The maximum permissible levels of these compounds, in drinking water and wastewaters discharged to environment, set by the WHO and a number of countries are very low (from μg/dm3 to a few mg/dm3). Several common treatment technologies, which are nowadays used for removal of inorganic contaminants from natural water supplies, represent serious exploitation problems. Membrane processes such as reverse osmosis and nanofiltration, ultrafiltration and microfiltration in integrated systems, Donnan dialysis and electrodialysis as well as membrane bioreactors, if properly selected, offer the advantage of producing high quality drinking water without inorganic substances as well as purified wastewater which can be drained off to natural water sources

Abstract

Escherichia coli is Gram-negative optionally anaerobic roads which belongs to Enterobacteriaceae family. Includes in a physiological bacterial flora of human and warm-blooded animals large intestine. Escherichia coli is being met in abiotic elements of the environment so as waters, wastewater, sewage sludge, soil and the food. This bacterium is showing the pathogenicity in named terms for the peoples, triggering diseases mainly: gastrointestinal tract and urinary.

Quality and quantitative proposed detections method of the bacteria E. coli contains five/six steps:

- appointment dry suspended solid,

- preparation averaged, test of sample and resuscitation of bacteria,

- making dilutions,

- enrichment and differentiation in chromogenic-selective medium,

- enumerating the amount of cfu E. coli in 1 g of a dry weight,

- optionally, the biochemical identification

., Dobrzański D.: Hydrogeochemia strefy aktywnej wymiany wód podziemnych , Warszawa, Wyd. PWN, 2007. 7. Mrozowska J.:, Laboratorium z mikrobiologii ogólnej i środowiskowej . Gliwice, Wyd. Politechniki Śląskiej, 1999. 8. POLSKA NORMA PN-C-04615-21:1980 - Woda i ścieki. Badania mikrobiologiczne. Oznaczanie bakterii Thiobacillus ferrooxidans metodą hodowli na pożywce płynnej . 9. Schlegel H. G.:, Mikrobiologia ogólna , Warszawa, PWN, 2003.

wodą w stawach rybnych na stosunki wodne przyległych gruntów ornych [The effect of water management in fishponds on water relations in adjacent arable lands]. Inżynieria Rolnicza. Nr 8 (28) p. 303-310. PŁOWENS T. 2004. Operat wodno-prawny. Ośrodek Pstrągowy Łoźnica. Rzeka Gowienica. Powiat Goleniów, Gmina Przybiernów [Legal water documentation. Rainbow trout farm Łoźnica. The Gowienica River. Goleniów County, commune Przybiernów]. pp. 24. PN-C-045760-6:1973. Woda i ścieki. Badania zawartości związków azotu. Oznaczanie azotu azotynowego metodą kolorymetryczną z kwasem

Abstract

The Służew Stream, a 14.9 km long watercourse, is part of an ancient river called Sadurka that starts its course in the Warsaw district of Ochota and flows into the Wilanów Lake. In the 19th and 20th centuries, the watercourse received industrial and municipal sewage from Warsaw and its environs, but nowadays only rain and snow meltwater is discharged into the stream. Freshwater sediments of five reservoirs in the catchment area of the Służew Stream - Wilanów Lake, Powsinów Lake, Pond in the Horse Racing area, Lake at Morgi and South Pond in the Wilanów Park - were analysed for the contents of Cr, Cu, Pb, Zn, Ni, Cd and Hg. The following concentrations have been determined: chromium - from 5 to 274 mg/kg, copper - from 5 to 274 mg/kg, lead - from 3 to 310 mg/kg, zinc - from 44 to 1430 mg/kg, nickel - from 3 to 55 mg/kg, cadmium - from 0.3 to 37.3 mg/kg and mercury - from 0.010 to 0.810 mg/kg (Fig. 2-5). The studies have shown that water sediments of Pond in the Horse Racing area, South Pond and Wilanów Lake, supplied by the Służew Stream waters, are characterised by a very high content of heavy metals. In contrast, water sediments of Powsinów Lake and Lake at Morgi, recharged by drainage ditches flowing into the stream, are characterised by much lower concentrations of these elements, but the levels are still much greater than the geochemical background.