Katarzyna Ignatowicz

The impact of sewage sludge treatment on the content of selected heavy metals and their fractions

ABSTRACT The aim of the study was to assess the physicochemical properties of compost made of municipal sewage sludge from selected Municipal Sewage Treatment Plant. Content of basic macroelements and heavy metals (Zn, Cu, Cr, Cd, Ni, Pb, Hg, Mg, Ca, N, P, K, Na) and their fractions was determined by means of BCR method. Based on the analyzes, it was found that the content of heavy metals in compost did not exceed the limits set by natural land management of sewage sludge; the compost is very abundant in biogenic elements ‐ nitrogen and phosphorus – and it can be also considered a significant source of calcium and magnesium. The analysis of results obtained from the three‐stage chemical extraction revealed that deposits subjected to aerobic stabilization and composting accumulate metals (in descending sequence) in fractions III and II, i.e. fractions virtually inaccessible to the ecosystem in optimal conditions of use. HighlightsContent of heavy metals in the compost does not exceed the limits set for natural utilization.Sewage sludge after treatment accumulate metals in fractions III and II.Compost is very abundant in biogenic elements calcium and magnesium.

Influence of bio-preparation on wastewater purification process in constructed wetlands

Technological system of analyzed wastewater treatment plant is in part a biological bed of soil-reed in parallel arrangement. Unusual application is the application of two independent purification lines where in the second line, a bio-preparation is additionally dosed. The constructed wetland provides high removal of organic compounds expressed as BOD5 and COD, as well as reducing the concentration of ammonia nitrogen and phosphates. This indicates a high performance of such a sewage treatment plant.

USING PHYTOREMEDIATION AND BIOREMEDIATION FOR PROTECTION SOIL NEAR GRAVEYARD

The aim of present research was to assess the usefulness of Basket willow (Salix viminalis) to phytoremediation and bioremediation of sorption subsoil contaminated with pesticides. Studies upon purification of sorption material consisting of a soil and composting sewage sludge were conducted under pot experiment conditions. The study design included control pot along with 3 other ones polluted with pesticides. The vegetation season has lasted since spring till late autumn 2015. After acclimatization, the mixture of chloroorganic pesticides was added into 3 experimental pots. After harvest, it was found that pesticide contents in sorption subsoil (from 0.0017 to 0.0087 mg kg DM) were much higher than in control soil (from 0.0005 to 0.0027 mg kg DM). Achieved results initially indicate that Basket willow (Salix viminalis) can be used for reclamation of soils contaminated with pesticides, particularly for vitality prolongation of sorption barrier around the pesticide burial area. In future, it would allow for applying the sorption screen around pesticide burial area, which reduces pesticide migration into the environment, and grown energetic plants – through phytoremediation – would prolong the sorbent vitality and remove pesticides from above ground parts by means of combustion.

THE ASSESSMENT USABILITY OF VIRGINA MALLOW Sida Hermaphrodita FOR PHYTOREMEDIATION OF SOIL CONTAMINATED WITH PESTICIDES

The aim of present research was to assess the usefulness of Virgina mallow Sida Hermaphrodita to phytoremediation of sorption subsoil contaminated with pesticides. Studies upon purification of sorption material consisting of a soil and sewage sludge were conducted under pot experiment conditions. The vegetation season lasted since spring until late autumn 2015. After acclimatization, the mixture of chloroorganic pesticides was added into experimental pots. After harvest, it was found that pesticide contents in sorption subsoil (from 0.3588 to 0.3991 mg kg DM) were much higher than in control soil (from 0.1600 to 0.2170 mg kg DM). The achieved results initially indicate that Virginia mallow can be used for reclamation of soils contaminated with pesticides, particularly for vitality prolongation of sorption barrier around the pesticide burial area. In the future, it would allow for applying the sorption screen around pesticide burial area, which reduces pesticide migration into the environment, and grown energetic plants – through phytoremediation – would prolong the sorbent vitality and remove pesticides from above ground parts by means of combustion.

COD FRACTIONS CHANGES DURING SEWAGE TREATMENT WITH CONSTRUCTED WETLAND

The purpose of the presented research work was to find out COD fractions in raw wastewater and during treatment with constructed wetland (CW) system. The tests were performed in CW system with average flow of about 4 m3/day. In raw wastewater the highest concentration of fraction in organic suspended solid easy biodegradable (XS – 250 mg O2/l) was observed. The same situation was with dissolved organic easy biodegradable matter (SS – 250 mg O2/l). Lower quantity of non-biodegradable fractions dissolved and in suspended solids were observed (SI – 27 mg O2/l, XI – 83.33 mg O2/l). More than 80% of total COD was as biodegradable fractions (SS + XS). After treatment with CW system the highest concentration was observed for dissolved nonbiodegradable fraction (SI – 27 mg O2/l). Lower concentration was for biodegradable fraction in suspended solid (XS – 3.33 mg O2/l). More than 89% of total COD was in biological non-biodegradable fraction (SI + XI).

Application of Sokolka compost to protect pesticide graveyard area

The paper presents the results of the researches in sorption process. Selected waste materials were checked to build a barrier for pesticide migration from existing graveyards. Due to primary researches Sokolka compost was selected for further researches. The sorption barrier was designed by the surface and underground water run-off. The line of the barrier was made around the centre of graveyard, 0.5 meter width and 4.0 meters deep up to the non-permeable ground layer. GC analyses have shown the presence of pesticides in piezometer before the barrier and no pesticides in water outside sorption barrier. Due to researches it was found that prevention barrier was successful.

Pesticide Burial Grounds in Poland – Actuality Problem

Until 30th June 2010, Poland liquidated a total of 180 burial grounds containing about 16.4 thousand Mg of expired pesticides and 97 warehouses containing 0.54 thousand Mg of waste. In the period from 1st January 2011 till 31st December 2013, a total of 28 burial grounds containing about 5.4 thousand Mg of obsolete pesticides were liquidated. Only 4 burial grounds containing about 278.43 Mg wastes remained for liquidation on 31st December 2013. Currently, 3 objects remained for the liquidation. The adopted course of action connected with burial grounds is to increase the involvement of the public administration to remove them in the provinces of Lower Silesia, Opole and Podlasie (finalization of conducted administrative proceedings and enforcement of their provisions).

Removal of Nitrogen Compounds from Wastewater in SBR Reactors with Brenntaplus VP1

The paper presents the efficiency of nitrogen removal from wastewater using Brenntaplus VP1 as an external carbon source. The study was conducted during the municipal wastewater treatment process in two independent activated sludge chambers of SBR type. One of the chambers contained glycerol as the source of easily available organic compounds. The study showed that the use of Brenntaplus VP1 as the external carbon source during wastewater treatment resulted in a higher efficiency of nitrogen removal than in the reactor without the external carbon source applied, resulting in low level of the COD value in the treated wastewater. There was a significant acceleration of the denitrification process as compared to the control reactor.

Chloroorganic Pesticide Adsorption from Water Solution Using Sewage Sludge Vermicompost as a Natural Sorbent

Dozens of thousands of tons of pesticide waste have been stored since 1950s. The corrosion of concrete bunkers and wells where the expired pesticides are deposited causes the risk of toxic leakage due to deteriorating conditions of these constructions. Such hazardous spill might be transported by underground waters in the form of so-called underground inflow and subsequently might reach a network of surface waters. Evaluating the adsorption potential of natural sorbent for pesticide was the main goal of this research. The adsorption balance was examined in order to analyze the influence of the adsorption mechanism of HCH molecules on vermicompost. The adsorption of HCH isotherms by vermicompost at constant temperature was tested experimentally. The Freundlich, Langmuir and BET’s adsorption isotherm models describe the experimental data within the acceptable error ranges. The Freundlich model proved to be more suitable for the experimental data. The form of isotherms indicates that HCH is adsorbed as a monolayer; therefore no obstacles occur in order for water and pesticide molecules to cover the adsorption surface.

Removal of carbon, nitrogen and phosphorus in constructed wetland for single household wastewater treatment

The article presents the results of the research with the household sewage treated by constructed wetland system. For effectiveness evaluation of sewage treatment plant, the sampling events were performed in 2015-2018. The samples were taken from: septic tank, after treatment in vertical flow constructed wetland and from aerobic pond. The removal efficiency of organic matter as well as biogenic compounds was evaluated. The carried out investigation confirmed the high efficiency of organic compounds removal. The removal of BOD5 was up to 94,45% and COD up to 75,8%.