Editor's comment
I. Simeonov 3-4
I. Human and biosphere
“Mars-500” project - ground-based experiment facilityTania Ivanova, Ivan Dandolov 5-14
In situ laser elemental and isotopic analysis of industrially-polluted with heavy metals water samples
Biana Simeonova, Lubomir Simeonov 15-20
Estimation of the dynamics of the Lumina lake floating reed islands in the territory of the Danube Delta biosphere reserve, using aerospace and GPS data for the period 1972 - 2009
Iva Ivanova, Roumen Nedkov 21-26
II. Noise and environment
Port complex, ports and noise factor
Nikolai Nikolov, Asen Pisarski, Jeni Staykova 27-36
III. Technologies for depolution
Environmental pollution control of Pb(II)-ions in thermal power plant byproducts by a selective chemical sensorSylvia Boycheva 37-42
IV. Microrganisms and environment
Tatyana Avramova, Anna Sotirova, Nadejda Fuchedjieva, Irina Lazarkevich, Danka Galabova 43-47
V. Ecological and sustainable agriculture
Changes in soil properties
resulting from fertilization by digestate obtained in biogas
production
E. Zlatareva, S. Marinova, K. Pchelarova, R. Toncheva, A. Katsarova, S. Myhaylova 48-52
VI. Renewable energy
sources
Microbial fuel cells in
wastewater treatment
Husein Yemendzhiev, Gergana Peeva, Valentin Nenov 53-59
VII. New developments
Pilot-scale biogas plant
for research and development of new technologies
Ivan Simeonov, Boyko Kalchev, Snezhanka Mihaylova, Venelin Hubenov, Georgi Valevski Anatoliy Aleksandrov, Rashko Georgiev 60-67
VIII. Jubilee
Prof. Alexander
Sadovski at the age of 75
68-69
IX. In Memoriam
Prof. Nikolai Nikolov 70
“MARS-500” PROJECT: GROUND-BASED EXPERIMENT FACILITY
Tania Ivanova, Ivan Dandolov
Abstract: A 520-day experiment "Mars-500", simulating manned mission to Mars was completed successfully in the Institute of BioMedical Problems (IBMP) in Moscow on 5 November 2011. An international crew have been sealed in a Ground-Based Experiment Facility (GEF), mock-up of a long-distance spacecraft, since 3 June 2010. The main purpose of the experiment was to help prepare for a real mission to Mars, gathering data, knowledge, and experience, and to assess the technical and operational characteristics of the facility. The study will be of great help to shed light on key psychological and physiological effects of being in such an enclosed environment for such an extended period of time. Greenhouse facilities and related experiments in GEF, to study the biological, technological and psychological aspects of their use, as part of the Life Support Systems during the Martian mission, are described in brief.
Keywords: Mars-500, SVET Space Greenhouse, Greenhouse module
Biana Simeonova, Lubomir Simeonov
Asbtract: A description of a simple method for preparation of laser targets from water solutions with different concentrations of the metals Na, Mg, Fe, Ni, Cd and Hg is presented. In a descending row from 1000 to 62.5 ppb and in quantities of a 0.25 ml each, the solutions were carefully evaporated on glass holders and the produced sedimentation residues were investigated with a miniature and portable time-of-flight laser mass analyzer. Discussed are the analytical possibilities of the laser time-of-flight mass-spectrometry to produce express and stable elemental and isotopic mass spectra of environmental aqueous samples directly near the places of sample collection and several related problems as sample preparation, multielement chemical analysis and reliability of the analytical results.
Keywords: elemental and isotopic analysis, laser mass spectrometry, environmental in-situ chemical analysis
ESTIMATION OF THE DYNAMICS OF THE LUMINA LAKE FLOATING REED ISLANDS IN THE TERRITORY OF THE DANUBE DELTA BIOSPHERE RESERVE, USING AEROSPACE AND GPS DATA FOR THE PERIOD 1972 - 2009
Iva Ivanova, Roumen Nedkov
Abstract: In the paper the dynamics of the floating islands in Lumina Lake in the lakes complex Rosu–Puiu–Lumina in the Danube Delta Biosphere Reserve, using remote sensing methods and aerospace information in the period 1972-2009, is described. The methodology involves detection, identification and recognition of the components situated in Danube Delta Biosphere Reserve.
The purpose of this paper is to analyze the state of the lakes complex Rosu–Puiu–Lumina, which will be helpful for making an adequate decision for a better management of the reserve and preservation of these floating islands with minimum impact on the native flora and fauna.
Keywords: floating reed islands, Danube Delta, satellite images, remote sensing
PORT COMPLEX, PORTS AND NOISE FACTOR
Nikolai Nikolov, Asen Pisarski, Jeni Staykova
Summary. The article
provides an analysis of urban, technical and environmental
conditions and development priorities of the main Bulgarian
ports and port facilities. Below are the noise characteristics
of different types of vessels.
Based on the author's original theory of quazicylindrical
sound waves is derived formula for calculating noise levels
and a method for determining the required sanitary-protective
zone around waterways and port facilities, which provide
acoustic comfort in adjacent residential neighborhoods.
Keywords: Ports,
noise level, health protection zone
ENVIRONMENTAL POLLUTION CONTROL OF Pb(II)-IONS IN THERMAL POWER PLANT BYPRODUCTS BY A SELECTIVE CHEMICAL SENSOR
Sylvia Boycheva
Abstract: A developed Pb(II)-ion-selective potentiometric chemical sensor from the “coated-wire” type was applied for detection of concentration levels of Pb2+-ions in byproducts from Thermal Power Plants. Fly ash (FA) obtained as mineral wastes from the incineration of lignite coals and collected in the electrostatic precipitators was subjected to this analysis after its liquidizing by alkaline melting and acidic dilution. The total concentration of lead accumulated by FA was measured of the order of 85 ppm. The obtained result was verified by instrumental inductively coupled plasma (ICP) analysis. The Pb(II)-ion-selective chemical sensor used has been preliminary studied with respect to its analytical performance related to its membrane composition, which has been evaluated by the following parameters: slope (S=29 mV dec-1) and linear range (L=10-5-10-1 mol l-1) of the calibration function, working pH-range (2≤pH≤4), detection limits (5.3 10-6 mol l-1), response time (τ95=1-5 s), good selectivity in the presence of number of metallic ions. Slurry from the absorber of flue gas desulphurization system operating on limestone-gypsum method with intensive force oxidation was also subjected to the Pb2+-ions concentration level evaluation after preliminary treatment. The measured potential was out of detection limits of the chemical sensor devices, which means that is below 5.3 10-6 mol l-1 (<1 mg l-1).
Keywords: chemical sensors, heavy metals, fly ash, ion-selective electrodes
EFFECT OF SURFACTANTS ON GROWTH AND CELL SURFACE PROPERTIES OF BACTERIAL ISOLATES FROM INDUSTRIAL POLLUTED WATER
Tatyana Avramova, Anna Sotirova, Nadejda Fuchedjieva, Irina Lazarkevich, Danka Galabova*
Abstract. Effect of surfactants (nonionic, cationic and anionic) on microbial cell growth, permeability and hydrophobicity of bacterial strains, members of a microbial consortium, isolated from lubricant-polluted water was studied. Bacterial strains were representatives of three genera, Enterococcus; Staphylococcus; Alcaligenes and were selected according to their ability to grow on n-hexadecane. It was shown that the surfactants have not positively influence on the capability of the tested strains to utilize the hydrophobic carbon substrate n-hexadecane. The results demonstrated that the surfactants have detrimental effect on the growth of strains and this was dependent on the surfactant concentration. At high concentrations the cationic surfactant has a markedly toxic effect on the selected strains. It was found that in presence of surfactants at all used concentrations the cell surface became more hydrophobic and that leads to partial overcome of inhibitory effect. The results obtained were discussed in attempt to evaluate the role of surfactants in bioremediation of hydrocarbon-polluted sites.
Keywords: surfactants; cell surface properties; n- hexadecane; Enterococcus; Staphylococcus; Alcaligenes
CHANGES IN SOIL PROPERTIES
RESULTING FROM FERTILIZATION BY DIGESTATE OBTAINED IN BIOGAS
PRODUCTION
E. Zlatareva, S. Marinova, K. Pchelarova, R. Toncheva, A. Katsarova, S. Myhaylova
Abstract: In recent years, a shortage of organic fertilizers is observed in our country. This requires a demand for reserves. The lack of sufficient electricity in Bulgaria raises questions related to renewable energy sources. Interest in the production of biogas from organic waste is growing increasingly in recent years. In anaerobic digestion a secondary organic product - compost is obtained, rich in macro and micronutrients and should seek its implementation in agricultural practice. The aim of the study is to establish the applicability of the digestate as a fertilizer resource and its influence on changes in chemical and agrochemical soil properties. A vegetation experiment with lettuces is conducted on two soil types, alluvial-meadow and vertisols. It was found that on both types of soil with increasing dose of compost the plants assimilable phosphorus and potassium are significantly increased. Increases the amount of mineral nitrogen, which is at the expense of the nitrate form. Slightly increases the amount of water-soluble salts in the soil, without risk of salinization.
Keywords: compost, vegetation experiments, water-soluble salts
E. Zlatareva, S. Marinova, K. Pchelarova, R. Toncheva, A. Katsarova, S. Myhaylova
Abstract: In recent years, a shortage of organic fertilizers is observed in our country. This requires a demand for reserves. The lack of sufficient electricity in Bulgaria raises questions related to renewable energy sources. Interest in the production of biogas from organic waste is growing increasingly in recent years. In anaerobic digestion a secondary organic product - compost is obtained, rich in macro and micronutrients and should seek its implementation in agricultural practice. The aim of the study is to establish the applicability of the digestate as a fertilizer resource and its influence on changes in chemical and agrochemical soil properties. A vegetation experiment with lettuces is conducted on two soil types, alluvial-meadow and vertisols. It was found that on both types of soil with increasing dose of compost the plants assimilable phosphorus and potassium are significantly increased. Increases the amount of mineral nitrogen, which is at the expense of the nitrate form. Slightly increases the amount of water-soluble salts in the soil, without risk of salinization.
Keywords: compost, vegetation experiments, water-soluble salts
MICROBIAL FUEL CELLS IN WASTEWATER TREATMENT
Husein Yemendzhiev, Gergana Peeva, Valentin Nenov
Abstract: The conventional wastewater treatment technologies are energy demanding. Aeration, mixing, activated sludge utilization and mineralization processes are connected with consumption of high amounts of energy. This study deals with the improvement of wastewater treatment processes in this direction by using Microbial fuel cells (MFCs).
The results obtained demonstrate the potential of this technology in water treatment and energy production.
By application of MFC we managed to reduce organic content of polluted water, to purify copper contaminated fluid and to produce electric energy by oxidation of organic wastes.
Keywords: Microbial fuel cells, copper removal, wastewater treatment
PILOT-SCALE BIOGAS PLANT FOR
RESEARCH AND DEVELOPMENT OF NEW TECHNOLOGIES
Ivan Simeonov, Boyko Kalchev, Snezhanka Mihaylova, Venelin Hubenov, Georgi Valevski, Anatoliy Aleksandrov, Rashko Georgiev
Abstract: Ňhe paper describes a new pilot-scale biogas plant of the Institute of Microbiology – Bulgarian Academy of Sciences. The equipment includes: a 100 dm3 pilot bioreactor, a 200 dm3 metal gasholder, sensors, actuators, a two-level automatic process monitoring and control system, a fire and explosion protection system and two web cameras. The monitoring and control system is composed on the lower level of a controller Beckhoff, and on the higher level – a PC with specialized software (under development). The pilot biogas plant is designed to work out and scale up various AD technologies based on different types of feedstock. All the data will be stored on the PC for quick reference and possibly data mining, parameter identification and verification of different AD mathematical models.
Key words: AD, biogas, sensors, monitoring and control system.
Ivan Simeonov, Boyko Kalchev, Snezhanka Mihaylova, Venelin Hubenov, Georgi Valevski, Anatoliy Aleksandrov, Rashko Georgiev
Abstract: Ňhe paper describes a new pilot-scale biogas plant of the Institute of Microbiology – Bulgarian Academy of Sciences. The equipment includes: a 100 dm3 pilot bioreactor, a 200 dm3 metal gasholder, sensors, actuators, a two-level automatic process monitoring and control system, a fire and explosion protection system and two web cameras. The monitoring and control system is composed on the lower level of a controller Beckhoff, and on the higher level – a PC with specialized software (under development). The pilot biogas plant is designed to work out and scale up various AD technologies based on different types of feedstock. All the data will be stored on the PC for quick reference and possibly data mining, parameter identification and verification of different AD mathematical models.
Key words: AD, biogas, sensors, monitoring and control system.