Pranas Baltrėnas

Use of Dynamic Factors to Assess Metal Uptake and Transfer in Plants—Example of Trees

To evaluate plant responses and compare metal uptake by different plants, several parameters and references have been used by researchers in the last few years. However, they express only the first-level comparison, i.e. biogeochemical comparison of different media (plant and soil) occurs in one place, at the same time and under the same circumstances. To integrate information about metal concentration in different media or plant organ and provide comparison of the process between control and treated cases, the second-level factors, the dynamic factors, are needed. Differently from the factors mentioned in the existing literature, they are able to show changes in processes under environmental changes rather than changes only in metal quantities. They are related both to internal (physiological) and external (ecological) factors. The paper introduces the use of dynamic factors for assessment of transfer and translocation of metals (Zn, Pb, Ni, Mn, Cu and Cr) in Scots pine (Pinus sylvestris L.), silver birch (Betula pendula) and black alder (Alnus glutinosa). Factor values and their implications are discussed in the paper.

Integrated evaluation of aerogenic pollution by air-transported heavy metals (Pb, Cd, Ni, Zn, Mn and Cu) in the analysis of the main deposit media

The composition of the ambient air is constantly changing; therefore, the monitoring of ambient air quality to detect the changes caused by aerogenic pollutants makes the essential part of general environmental monitoring. To achieve more effective improvement of the ambient air quality, the Directive 2008/50/EC on ‘Ambient Air Quality and Cleaner Air for Europe’ was adopted by the European Parliament and the European Council. It informed the public and enterprises about a negative effect of pollution on humans, animals and plants, as well as about the need for monitoring aerogenic pollutants not only at the continuous monitoring stations but also by using indicator methods, i.e. by analysing natural deposit media. The problem of determining the relationship between the accumulation level of pollutants by a deposit medium and the level of air pollution and its risks is constantly growing in importance. The paper presents a comprehensive analysis of the response of the main four deposit media, i.e. snow cover, soil, pine bark and epigeic mosses, to the long-term pollution by aerogenic pollutants which can be observed in the area of oil refinery influence. Based on the quantitative expressions of the amounts of the accumulated pollutants in the deposit media, the territory of the oil refinery investigated in this paper has been referred to the areas of mild or moderate pollution.

Experimental investigation of biogas production using biodegradable municipal waste

Abstract Waste is undesirable matter, which is most frequently generated by human activity. It is one of the sources of environmental pollution. In the contemporary world, with growing population, the amounts of generated waste are increasing as well. Unsorted municipal waste, including biodegradable waste, is transported to operated landfills. A negative impact of landfills on the environment is determined by waste as well as gas emissions and polluted sewage. Annual increase in amounts of waste is one of the most urgent problems of today, and therefore effective measures have to be employed to address it. In order to apply anaerobic organic waste treatment technologies and minimise the harmful effect on the environment, waste has to be sorted. The article presents the results of experimental investigations performed with fruit, vegetable and meat waste and its mixtures. The concentrations of methane, hydrogen sulphide and oxygen under mesophilic operation of a bioreactor were observed during the experim...

Testing of Chlorella/Scenedesmus microalgae consortia for remediation of wastewater, CO2 mitigation and algae biomass feasibility for lipid production

AbstractIndustry, transport and unsustainable agriculture result in the increased quantity of wastewater, release of nutrients and emission of carbon dioxide that promotes eutrophication of water bodies and global climate change. The application of microalgae for phycoremediation, their biomass use for human needs may increase sustainability and have a positive effect on the regional development. The experiments were carried out in order to establish the feasibility of treating the local municipal wastewater with microalgae consortia and their biomass potential for biofuel production. The results revealed that Chlorella/Scenedesmus consortium eliminated up to 99.7–99.9% of inorganic phosphorus and up to 88.6–96.4% of inorganic nitrogen from the wastewater within three weeks. The ammonium removal was more efficient than that of nitrate. Chlorella algae grew better in diluted, while Scenedesmus – in the concentrated wastewater. The consortium treated wastewater more efficiently than a single species. The ma...

A biochar-based medium in the biofiltration system: Removal efficiency, microorganism propagation, and the medium penetration modeling

ABSTRACT Biofiltration is a method of biological treatment belonging to cleaner technologies because it does not produce secondary air pollutants, but helps to integrate natural processes in microorganisms for decomposing volatile air pollutants and solving odor problems. The birch wood biochar has been chosen as a principal material for biofilter bed medium. The experiments were conducted at the temperatures of 24, 28, and 32 °C, while the concentration of acetone, xylene, and ammonium reached 300 mg/m3 and the flow rate was 100 m3/hr. Before passing through the stage of the experimental research into the packing material inside biofilters, microorganisms were introduced. Four strains of microorganisms (including micromycetes Aspergillus versicolor BF-4 and Cladosporium herbarum 7KA, as well as yeast Exophiala sp. BF1 and bacterium Bacillus subtilis B20) were selected. At the inlet loading rate of 120 g/m3/hr, the highest elimination capacity of xylene in the biochar-based biofilter with the inoculated medium was 103 g/m3/hr, whereas that of ammonia was 102 g/m3/hr and that of acetone was 97 g/m3/hr, respectively. The maximum removal efficiency reached 86%, 85%, and 81%, respectively. The temperature condition (though characterized by some rapid changes) can hardly have a considerable influence on the biological effect (i.e., microbiological activity) of biofiltration; however, it can cause the changes in physical properties (e.g., solubility) of the investigated compounds. Implications: The birch biochar can be successfully used in the biofiltration system for propagation of inoculated microorganisms, biodegrading acetone, xylene, and ammonia. At the inlet loading rate of 120 g/m3/hr, the highest elimination capacity of xylene was 103 g/m3/hr, that of ammonia was 102 g/m3/hr, and that of acetone was 97 g/m3/hr, respectively. The morphological structure of biochar can be affected by the aggressive air contaminants, causing the change in the medium specific surface area, which is one of the factors controlling the biofilter performance. Although biological effects in biofiltration are typically considered to be more important than physical effects, the former may be more important for compounds with high Henry’s Law coefficient values, and the biofilter design should thus provide conditions for better compound absorption.

Trace metal concentration and speciation in storm water runoff on impervious surfaces

AbstractUrban storm water runoff (USWR) often transports various trace metals, affecting the quality of receiving waters. Metal concentration and speciation in USWR were investigated by analysing data collected during a storm event on 19 July 2012. USWR samples were taken from a low–traffic intensity road, a pathway in a car–free pedestrian zone, and a galvanized metal roof located in the area of Vingio Park in the city of Vilnius, Lithuania. The metals were mostly in the insoluble form at all three sites, being more than 80% of the total amount measured, irrespective of the water quality characteristics and types of surface area. The partitioning coefficient (log Kd) of trace metals decreases in the order Zn > Cu ≈ Mn ≈ Pb >> Cd. The USWR types characterized by a higher pH or dissolved organic carbon (DOC) concentration produced a higher fraction of Cd, Mn, Pb, and Zn bound to fulvic acids (FA).

Investigation and evaluation of carbon dioxide emissions from soil in Neris Regional Park

Abstract. Soils release around 20% of the total CO2 content to the atmosphere; consequently, forest and agricultural ecosystems have a big influence on CO2 balance. Until recently, the majority of CO2 measurements of Lithuanian soils were either carried out under laboratory conditions or obtained by applying outdated research methods. CO2 investigations in Neris Regional Park were carried out under field conditions during plant vegetation by using the CO2 emission measuring instrument ADC BioScientific and soil chamber, the analysis system of which includes a metal collar of ∼0.9 m2 area. This infrared gas analysis system performs measurements within the range of 0–2000 ppm, with an error of 1 ppm. The emissions error is a mere ±2%. The system allows making reliable measurements within the temperature range of −5 °C to +50 °C.

Investigation and Evaluation of Copper and Zinc Concentration Tendencies in Pinus sylvestris L. Tree-Rings

Abstract Free trace metals are one of the most relevant environmental problems of today; consequently, it is becoming important to evaluate their spatial distribution and accumulation rates in the natural environment. For this analysis, Scots pine (Pinus sylvestris L.) was chosen as suitable for indication of environmental stress because of its simple wood structure and of well distinct tree-rings for evaluation of temporal trace metals concentration changes. For the primary study, we chose the most evenly forested territory – the south-eastern part of Lithuania. The study results revealed that the background Zn concentration in Scots pines is 7.2 mg·kg−1 and that of Cu amounts to 2.5 mg·kg−1 The anomaly concentration of both trace metals in Scots pine defined to be higher than 21.3 for Zn and 9.0 mg·kg−1 of d.w. for Cu. The Cu and Zn concentration in Scots pine stem distributed gradually with slightly increased values towards the bark. However, a lower concentration rate was noticed in the wood formed in...

DEM Simulation of the Impact of Ultrafine Glass Particles on the Partition Wall of the Multichannel Cyclone

This article focuses on the simulation of the impact of ultrafine particles on the rigid partition wall of the multichannel cyclone by applying the discrete element method (DEM). Ultrafine particles with diameters ranging from 0.1 to 10 µm are assumed to be most dangerous pollutants because of their property to easily penetrate the human circulatory system through the respiratory tract. An emphasis is placed on demonstrating the stick-rebound behavior of glass pollutant particles. The numerical experiment simulating the oblique impact load induced by mechanically generated inlet air flow has been numerically conducted. Hertz contact and short-range van der Waals attraction are the main forces describing normal contact, while their tangential counterpart is defined according to Coulomb friction law and by considering normal compression and attraction. Both normal and tangential models are modified to comprise the effect of energy dissipation due to adhesion hysteresis. Simulation results provide a theoretical framework for designing of the cyclone when a device is applied to capture ultrafine pollutant particles.

Research into acetone removal from air by biofiltration using a biofilter with straight structure plates

The biological air treatment method is based on the biological destruction of organic compounds using certain cultures of microorganisms. This method is simple and may be applied in many branches of industry. The main element of biological air treatment devices is a filter charge. Tests were carried out using a new-generation laboratory air purifier with a plate structure. This purifier is called biofilter. The biofilter has a special system for packing material humidification which does not require additional energy inputs. In order to extend the packing materials durability, it was composed of thermally treated birch fibre. Pollutant (acetone) biodegradation occurred on thermally treated wood fibre in this research. According to the performed tests and the received results, the process of biodestruction was highly efficient. When acetone was passed through biofilters packing material at 0.08 m s−1 rate, the efficiency of the biofiltration process was from 70% up to 90%. The species of bacteria capable of removing acetone vapour from the air, i.e. Bacillus (B. cereus, B. subtilis), Pseudomonas (P. aeruginosa, P. putida), Stapylococcus (S. aureus) and Rhodococcus sp., was identified in this study during the process of biofiltration. Their amount in the biological packing material changed from 1.6 × 107 to 3.7 × 1011 CFU g−1.