Malgorzata Pawlowska

The effect of bed properties on methane removal in an aerated biofilter--model studies.

The capacity of laboratory-scale aerated biofilters to oxidize methane was investigated. Four types of organic and mineral-organic materials were flushed with a mixture of CH(4), CO(2) and air (1:1:8 by volume) during a six-month period. The filter bed materials were as follows: (1) municipal waste compost, (2) an organic horticultural substrate, (3) a composite of expanded perlite and compost amended with zeolite, and (4) the same mixture of perlite and compost amended with bentonite. Methanotrophic capacity during the six months of the experiment reached maximum values of between 889 and 1036 gm(-2)d(-1). Batch incubation tests were carried out in order to determine the influence of methane and oxygen concentrations, as well as the addition of sewage sludge, on methanotrophic activity. Michaelis constants K(M) for CH(4) and O(2) were 4.6-14.9%, and 0.7-12.3%, respectively. Maximum methanotrophic activities V(max) were between 1.3 and 11.6 cm(3)g(-1)d(-1). The activity significantly increased when sewage sludge was added. The main conclusion is that the type of filter bed material (differing significantly in organic matter content, water-holding capacity, or gas diffusion coefficient) was not an important factor in determining methanotrophic capacity when oxygen was supplied to the biofilter.

A Possibility to Reduce Methane Emission from Landfills by Its Oxidation in the Soil Cover

Landfills of municipal wastes are considered to be a source of total methane emission to the atmosphere estimated at 20 to 70 Tg annually which is an important contribution (6–20%) to total anthropogenic emission (about 360 Tg). Atmospheric concentration of this very radiatively active gas (about 30 times more than CO2) is increasing at a rate of approximately 1% per year. One of the possibilities to reduce the ongoing methane concentration growth in the atmosphere is the reduction of anthropogenic emission by about 10%, which corresponds to the oxidation of 3/4 of methane emitted from landfills. According to some authors the cheapest and the most feasible way of decreasing methane emission from municipal wastes is increasing the degree of methane oxidation in the landfill cover soil.

Management of Pollutant Emission from Landfills and Sludge

Mitigation of gas emission from landfills. Pathway of POPs in the waste, wastewater and landfill leachate. Migration of heavy metals from waste disposal sites and sewage sludge. Minimization of the impact of waste and sewage sludge on the environment. Chemical composition and treatment of landfill leachate. Possibility of practical utilization of waste and sewage sludge. Miscellanea.

The Effect of Texture on Methane Oxidation Capacity in a Sand Layer — a Model Laboratory Study

The microbiological process of methane oxidation in soils has been recognised as an important component of the global budget of atmospheric methane, contributing in 6% to its removal from the atmosphere. However, this process plays an important role in decreasing methane emission from these sources which are isolated from the atmosphere by a soil layer e.g. recultivated municipal landfills. The consumption of methane in aerated soils is affected by many factors; one of them being the gas transport resistance within the soil. Four sand and gravel fractions characterised by different gas diffusion properties viz. 0.25–0.5 mm, 0.5–1.0 mm, 1.0–2.0 mm, 2.0–4.0 mm, were used in our study. Each of the fractions placed in columns (1m by 0.15 m in diameter) was purged from the bottom with methane with a constant rate. The difference between the amount of CH entering and leaving the column was a measure of the capacity for methane oxidation. The highest methane oxidation capacity (9.47±0.44 dm3m-2h-1) was observed in the case of 0.51.0mm fraction.

Effect of drilling mud addition on activated sludge and processes in sequencing batch reactors

AbstractLaboratory-scale sequencing batch reactors (SBR) with activated sludge were used for co-treatment of drilling mud and municipal wastewater. The influence of two doses of drilling mud, 1% (SBR2) and 3% (SBR3) of total added wastewater volume, on wastewater treatment efficiency and community of eukaryotes in activated sludge was examined. Addition of drilling mud significantly decreased the efficiency of TSS removal in SBR2 and SBR3 (from 97% in control bioreactor SBR1 to 75% and 49%, respectively), COD removal (from 93% to 57% and 48%, respectively) and removal (from 93% to 56% and 48%, respectively). Values of TSS concentration in outflow from SBR2 and SBR3 greatly exceeded the limit value appointed for the wastewater discharged into the environment. Drilling mud addition led to decrease in population and diversity of eukaryotes’ groups in activated sludge, which was reflected by changes in sludge biotic index (SBI). It amounted to 10 in all the SBRs at the beginning of the experiment, and in SBR1...

Shrink-swell potential, hydraulic conductivity and geotechnical properties of clay materials for landfill liner construction

Abstract This paper presents studies concerning the applicability of two clay materials for the construction of a sustainable landfill liner. The studies consisted in determination of basic characteristics of the materials, eg particle size distribution, bulk density, particle density, total porosity, pore size, mineralogy, specific surface area, nanoparticle size, and Atterberg limits, as well as measurements of their geotechnical and hydraulic parameters, such as in situ saturated hydraulic conductivity, modules of primary and secondary compression, cohesion, and angle of internal friction. Furthermore, the effects of compaction performed by the Proctor method at various water contents on swelling and shrinkage characteristics and saturated hydraulic conductivity were investigated in order to determine the compliance with the national requirements for selection of material for landfill liner construction. The determined characteristics and geotechnical parameters of the tested clay materials allowed qualifying them as suitable for municipal landfill construction. The shrinkage potential of the tested clays observed was rated as moderate to very high. The cyclic drying and rewetting of the clay materials performed resulted in a significant increase in saturated hydraulic conductivity. Thus, the clay sealing layers, as part of a multilayer liner, should be very carefully operated, preventing the drying out of the clay sealing and assuring the possibility of its constant saturation.

Control of Landfill Gases Emission with Particular Emphasis on Btex

Control of Landfill Gases Emission with Particular Emphasis on Btex Landfilling is the most popular way for waste disposal and has been widely applied globally. A large quantity of volatile organic compounds (VOCs) is released from landfills. Among them, BTEX (benzene, toluene ethylbenzene and xylene) is a major group of pollutants, which have now become a cause for concern worldwide because of their toxic properties. For this reason, strict regulations have come into force which induce researchers to find methods to reduce their emissions. This article contains descriptions of several aerobic metabolic pathways for the degradation of BTEX, which are provided by two enzymatic systems (dioxygenases and monooxygenases). Special attention was paid to biofiltration - a method for improving the efficiency of treatment of BTEX released from landfills. Degradacja gazów składowiskowych ze szczególnym uwzględnieniem BTEX Składowiska odpadów są najtańszą i najprostszą metodą ich zagospodarowania. Ze względu na uwalnianie z nich znacznych ilości lotnych związków organicznych (VOC) składowiska stanowią zagrożenie dla czystości powietrza, wód gruntowych oraz gleb. W grupie VOC uwalnianych ze składowisk odpadów najbardziej powszechne i jednocześnie bardzo toksyczne są BTEX (benzen, toluen, etylobenzen, ksyleny). Z tego też względu ważne jest poszukiwanie efektywnych metod eliminacji tych związków ze składowisk odpadów. W artykule przedstawiono obecny stan wiedzy odnoszący się do degradacji BTEX przez mikroorganizmy oraz opis metod stosowanych do usuwania BTEX ze składowisk odpadów ze szczególnym uwzględnieniem procesu biofiltracji.

Short-term Influence of Drilling Fluid on Ciliates from Activated Sludge in Sequencing Batch Reactors

Spent drilling muds are the liquid residues of rock drilling operations. Due to a high concentration of suspended solids and potentially detrimental chemical properties, they can negatively affect microorganisms participating in wastewater treatment processes. We evaluated the addition of a potassium-polymer drilling fluid (DF) to activated sludge in laboratory sequencing batch reactors (SBRs) for municipal wastewater treatment. Ciliate assemblage, the most dynamic component of eukaryotes in activated sludge, and which is highly sensitive to changes in the system, was evaluated. The average ciliate abundance dropped by about 51% (SBR 2; 1% DF added) and 33% (SBR 3; 3% DF added) in comparison to the control (SBR 1; wastewater only). A decrease in the total number of ciliate species during the experiment was observed, from 25 to 24 in SBR 2 and from 17 to 13 in SBR 3. Moreover, a drop in the number of dominant (>100 individuals mL) ciliate species was observed during the experiment-from eight in the control to five in SBR 2 and four in SBR 3-signaling noticeable changes in the quantitative structure of ciliate species. The species analyzed showed different responses to DF addition. The most sensitive was , which is bacteriovorus. In contrast, two predators, and , showed no reaction to DF addition. Our results indicate that addition of potassium-polymer DF, in doses of 1 to 3% of the treated wastewater volume, had no toxic effects on ciliates, but qualitative and quantitative changes in their community were observed.

Effects of Soil-Like Materials Mix from Drill Cuttings, Sewage Sludge And Sawdust on the Growth of Trifolium pratense L. and Transfer of Heavy Metals

Approximately 80000 tons of drilling waste is produced in Poland annually. This type of waste is relocated and deposited in waste neutralization plants or landfills. Eventually, it must be managed. Reuse of solid wastes might constitute a method of their utilization. The article investigates the use of drill cuttings, sewage sludge and sawdust for production of soil-like mixtures. The studies on evaluation of the possibility of economic application of soillike materials were carried out. The assessment was conducted on the basis of metal content in soil-like materials and plants cultivated on substrates produced of soil-like materials. In accordance with the valid legal regulations, the concentration of metals in soil-like materials enables their application on class II soils, i.e. arable land. The concentration of heavy metals in the plants cultivated on the substrates produced with soil-like materials is low and does not exceed the concentration of metals determined in animal feeding standards.

Short-term Influence of Two Types of Drilling Fluids on Wastewater Treatment Rate and Eukaryotic Organisms of Activated Sludge in Sequencing Batch Reactors

This work presents the results of studies on the impact of spent drilling fluids cotreated with municipal wastewater on the rate of the wastewater treatment process and the structure of the community of eukaryotic organisms inhabiting an activated sludge. The studies were conducted under laboratory conditions in sequencing batch reactors. The effect of added polymer-potassium drilling fluid (DF1) and polymer drilling fluid (DF2) at dosages of 1 and 3% of wastewater volume on the rate of removal of total suspended solids, turbidity, chemical oxygen demand, and the content of total and ammonium nitrogen were analyzed, taking into account the values of these parameters measured at the end of each operating cycle. In addition to the impacts on the aforementioned physicochemical indices, the influence of drilling fluid on the biomass of various groups of eukaryotes in activated sludge was analyzed. The impact of the drilling fluid was highly dependent on its type and dosage. A noticeable slowdown in the rate of the wastewater treatment process and a negative effect on the organisms were observed after the addition of DF2. This effect intensified after an increase in fluid dose. However, no statistically significant negative changes were observed after the introduction of DF1. Conversely, the removal rate of some of the analyzed pollutant increased.