Wyniki wyszukiwania - BazTech

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Modeling of solubilization dynamics of manure organic matter and phosphorus as a function of pH control and enzyme supplementation

Gungor K., Alkan-Ozkaynak A., Karthikeyan K. G., Evrendilek F., Gunasekaran S.

Environment Protection Engineering

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2016

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Vol. 42, nr 2

155--170

EN

The potential use of commercial enzyme and pH control has been investigated for enhancing dairy manure fermentation and modeling dissolved organic matter and orthophosphate (PO4-P) dynamics of fermenters. Anaerobic lab-scale batch fermenters (initial total solids concentration (TSo) = 3.8 wt. %) were fed with separated dairy manure solids and operated under pH controls (5 and 9.5). The enzyme-supplemented alkaline fermenters clearly outperformed the acidic fermenters in terms of chemical oxygen demand (COD) solubilization: ca. 50% vs. 20%, respectively. Soluble PO4-P in the acidic fermenters was comparably higher but constituted less than 20% of total phosphorus. Better soluble COD (>80%) and soluble PO4-P (>70%) yields were noted for the dilute fermenters (TSo = 0.6–0.8 wt. %). An existing model was retrofitted, calibrated and validated for simulating dynamics of soluble COD, volatile fatty acids, and soluble orthophosphate under various pH and enzyme conditions.

2

Characteristics of natural organic matter removed from water along with its treatment

Urbanowska A., Kabsch-Korbutowicz M.

Environment Protection Engineering

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2016

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Vol. 42, nr 2

183--195

EN

The object of this study was to examine the nature of natural organic matter (NOM) removed on each stage of water treatment train used in the “Mokry Dwór” Wrocław Water Treatment Plant (WTP) and to compare obtained results with water treatment efficiencies achieved with the use of membrane ultrafiltration, ion-exchange and UF/ion-exchange integrated processes. In the experiments fractional analysis with the use of polymeric resins (DAX-8, XAD-4 and IRA-958) was used. Obtained results have shown that most (56%) of the raw water NOM was found in fraction characterized by presence of humic and fulvic acids (VHA and SHA fractions). VHA fraction made the most of DOC removed in examined water treatment train and coagulation was mainly responsible for this effect. Integrated process consisting of MIEX®DOC ion exchange and PES 10 kDa ultrafiltration turned out to be very effective at high molecular weight hydrophobic compounds removal from water being much less efficient with hydrophilic compounds.

3

Comparison of mineral and organic nitrogen forms in regulated and restored sections of a small lowland river

Zieliński P., Jekatierynczuk-Rudczyk E.

Environment Protection Engineering

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2014

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Vol. 40, nr 2

33--46

EN

The lower, ending part of a small lowland Rudnia River (RR) in NE Poland was restored in 1999 and transformed into a meandering river. In this study, a few years after the natural connection between the main channel and its historic floodplain was restored, we examined the impact of river channel restoration on nitrogen dynamics and its biogeochemistry. Data were collected over a period of a year at monthly intervals from two sections of the river located on the regulated and restored sections. Spatial and temporal variations in the occurrence of mineral (NH(+4), NO(-2), NO(-3) and organic forms of nitrogen were investigated. Much higher average concentrations of organic nitrogen forms were found in the water from the restored part of the river than in the regulated one. Mineral nitrogen contribution to the total nitrogen (TN) pool was the highest, and the total organic nitrogen (TON) to total inorganic nitrogen (TIN) ratio exceeded 2 mg•dm-3 in the restored river section. The seasonal trend in concentration of organic nitrogen forms for the restored section was higher and statistically significantly different from the data recorded at the regulated river section. Geological, hydrological, and biogeochemical factors caused elevated organic nitrogen concentrations in the water at the restored part. The most important environmental parameters for nitrogen dynamics are geological structure of river valley, formation and condition of river banks ecotone zone, and water retention time in the river channel. Results from this study suggest that properly restored lowland river floodplains can be effective nitrate sink for mineral forms of nitrogen.

4

Isotopic effects of suspended organic matter fluxes in the Solina reservoir (SE Poland)

Koszelnik P.

Environment Protection Engineering

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2009

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Vol. 35, nr 4

13-19

EN

The aim of the study was to describe the source and fate of lacustrine suspended organic matter on the basis of nitrogen and carbon isotope effects. During complete depletion of dissolved silica in epilimnion, the differences in nitrogen isotope between substrates and products show that a primary production of organic matter (OM) in the euphotic zone of the reservoir is stimulated by nitrates. Additionally, in the hypolimnion, the decomposition of OM occurs, which in the case of a high primary production may lead to oxygen depletion.