Ecological Engineering and Environment Protection

doi.org/10.32006/eeep.2022.2.0517
HOW WHITE BIOTECHNOLOGY CAN CONTRIBUTE TO BIOECONOMY?
Jean Marie François^1,2¹Toulouse Biotechnology Institute (TBI), Université de Toulouse, CNRS, INRA, INSA,

135 Avenue de Rangueil, F-31077 Toulouse, France;

²Toulouse White Biotechnology center (TWB), UMS INRA –INSA,

135 avenue de Rangueil F31077-Toulouse, France

Abstract. Biotechnology in its broadest sense is the application of science and technology to living organisms to produce goods, products and services. It is segmented into 10 branches, of which white biotechnology, also called industrial biotechnology, is the oldest, having its roots in the Neolithic period with the transformation of food into fermented products attributed to divine intervention at that time. White biotechnology really took off after Louis Pasteur demonstrated that fermentation is caused by living organisms. This discovery was followed in the early 20^th century by the development of large-scale fermentation processes exploiting the intrinsic metabolic properties of microorganisms, such as solventogenesis in Clostridium or secondary metabolism for penicillin synthesis in Penicillium. With the advent of recombinant DNA in the 1970s, a new era of white biotechnology was born, with the ability to genetically manipulate microorganisms for the production of recombinant proteins and therapeutic agents, which notably boosted the biopharmaceutical sector. A third revolution in white biotechnology is nowadays occurring, driven by the strong societal demand to shift from a fossil fuel-based economy to one based on renewable carbon resources. The transition to so-called "bioeconomy" is expected to be slow and painful because it relies on the exploitation of "biological systems" that, unlike the chemical processes, are much more complex, inefficient, difficult to manage and still unpredictable. After a brief history of industrial biotechnology, I will present and address in this opinion paper some major challenges that await white biotechnology, using as an example our current work in the production of biosourced methionine, and I will discuss societal factors that could foster a bright future to white biotechnology in our modern society.
Keywords: industrial biotechnology, bioeconomy, systems and synthetic biology, bio-based products, chemicals

doi.org/10.32006/eeep.2022.2.1829

MICROBIOLOGICAL STUDY OF THE ANTHROPOGENIC PRESSURE ON THE YANTRA RIVER IN THE REGION OF VELIKO TARNOVO
Zvezdimira Tsvetanova, Dimitar Dimitrov, Hristo Naidenski
The Stephan Angeloff Institute of Microbiology at the Bulgarian Academy of Sciences
Abstract: The report discusses the microbiological status of the Yantra River in the region of the town of Veliko Tarnovo. Water samples collected at 11 points of the river stretch were analyzed for quantification of E. coli and coliforms, intestinal enterococci and heterotrophic bacteria. It was found increased levels of fecal indicator bacteria in the river waters, varying over time and along the riverside. The number of viable E. coli and enterococci increased under the influence of untreated wastewater influx and the Belitsa River.
Keywords: river water, E. coli, fecal indicators, intestinal enterococci, P. aeruginosa

doi.org/10.32006/eeep.2022.2.3044
A THEORETICAL OVERVIEW OF COMPRESSED AIR ENERGY STORAGE TECHNOLOGIES AND DEVELOPMENTS

Leila Bakhtiari, Dimitre Karamanev

Department of Chemical and Biochemical Engineering,The University of Western Ontario, Canada

Abstract. In our modern world, technological developments on the one hand, and global warming and its consequences, on the other hand, cause us to feel the necessity for reliable, cost-effective, and clean energy. Using renewable energy sources paired with compressed air energy storage can be a good option that meets these expected criteria. Although a compressed air energy storage system (CAES) is clean and relatively cost-effective with long service life, the currently operating plants are still struggling with their low round trip efficiencies. This paper illustrates an up-to-date review of compressed air energy storage systems containing changes in the conventional process to improve performance and increase efficiency. Three main categories of compressed air energy storage technology, diabatic, adiabatic, and isothermal, are analyzed theoretically. In addition, three components of a compressed air energy storage system including compression system, reservoirs, and expansion system are discussed here in detail. The advantages, disadvantages, and the technological readiness of different types of CAES are discussed.

Keywords: Compressed Air Energy Storage (CAES), Diabatic, Adiabatic, Isothermal.

doi.org/10.32006/eeep.2022.2.4555
THEORETICAL COMPARATIVE STUDIES OF THE BIOGAZ YIELDS FROM ONE-STAGE AND TWO-STAGE ANAEROBIC DIGESTION PROCESSES
Ning Pan¹, Haoping Wang¹, Yang Tian¹, Elena Chorukova², Ivan Simeonov², Nicolai Christov³ ¹LaFCAS Laboratory, Automation School, Nanjing University of Science and Technology, Nanjing, China²The Stephan.Angeloff Institute of Microbiology – Bulgarian Academy of Sciences, Sofia, Bulgaria³Centre de Recherche en Informatique, Signal et Automatique de Lille - UMR 9189, Université de Lille, France

Abstract. This paper deals with the theoretical comparison of biogas and energy yields of one-stage anaerobic digestion processes (OSAD) with biomethane production and two-stage anaerobic digestion processes (TSAD) producing biohydrogen and biomethane. The comparative study of the biogas yield from OSAD and TSAD systems is performed on the base on mathematical models obtained in our previous papers. The possible maximal yields of biohydrogen and biomethane are calculated by the static characteristics and extremum points of both systems. Simulation results suggest that in comparison to OSAD, the increase in biogas (biohydrogen and biomethgane) production of TSAD can reach to 75.18%. The energy produced from two-stage anaerobic digestion processes is 1.32 to 1.486 times greater than those from one-stage anaerobic digestion processes (depending of the inlet organics concentrations), which means TSAD is a better choice considering biogas and energy production.

Keywords: anaerobic digestion, one-stage, two-stage, mathematical modeling, static characteristics, biogas yields, energy yield

doi.org/10.32006/eeep.2022.2.5659
METHODOLOGY FOR REMOTE SENSING MONITORING OF ORGANIC WHEAT CROPS
Milen Chanev¹, Lachezar Filchev¹, Darina Valcheva²¹ Space Research and Technology Institute, Bulgarian Academy of Science² Institute of Agriculture - Karnobat, Agricultural Academy of Bulgaria

Abstract: In the presented methodology for aerospace monitoring of autumn wheat crops, grown under the conditions of organic farming, the ways of applying ground and aerospace methods are discussed in detail. This includes field experiments, phenological observations, GIS and remote sensing methods and data (data from Sentinel-2 satellite and WingtraOne unmanned aerial vehicle with MicaSense RedEdge-MX multispectral camera and RGB camera) and statistical analyses. In order to achieve the aim and objectives of the study, an experiment was conducted on a organically certified production field sown with einkorn (Triticum monococum) in the period 2020-2021. The field is part of the holding of ET "Borislav Slavchev" in the village of Byala Reka, Parvomai Municipality, South-Central Bulgaria on the soil type of leached chernozem clays, with a size of 136 da.

Keywords: remote sensing, wheat crops, organic agriculture, methodology

doi.org/10.32006/eeep.2022.2.6067

BACTERIAL DEGRADATION OF CELLULOSIC SUBSTRATES UNDER TERRESTRIAL AND LONG TERM MANNED SPACE MISSION CONDITIONS: A REVIEW (Part I)

Lyudmila Dimitrova¹, Venelin Hubenov¹, Lyudmila Kabaivanova¹, Yana Gocheva¹, Plamen Angelov², Hristo Najdenski¹¹ The Stephan Angeloff Institute of Microbiology at the Bulgarian Academy of Sciences² Space Research and Technology Institute at the Bulgarian Academy of Sciences
Abstract: The Earth and the lower atmosphere (troposphere and stratosphere) are constantly faced with numerous environmental challenges, one of which is the growing pollution due to the incineration of cellulose-containing waste with accumulating potential. In recent years scientists have focused on the complexity of ecological mechanisms in the biosphere of our planet - Earth, starting from laboratory, scaled and closed ecosystems. Onboard the spacecraft, textile products with antimicrobial properties are widely used which limits the spread of infections and ensures safety, comfort and resistance of the user. Another type of waste is the remains of sanitary and medical consumables, personal hygiene materials (e.g. wet and dry wipes, toilet paper, etc.), paper, inedible parts of greenhouse plants, etc., being usually subjected to microbial degradation. On Earth, the accumulation of these cellulose containing waste can cause serious environmental problems. Nowadays, many researchers are trying in experimental conditions on Earth to solve the problem of cellulose-containing waste by means of different approaches – burning, composting, burial, etc. The main risk and environmental problem is that the burial of waste in the soil and composting should contribute to the spread of microorganisms with pathogenic potential. Nevertheless, a promising approach is the microbial degradation of cellulose containing substrates realized by microbial consortia depending on the conditions of the surrounding environment. Therefore, the recent review aims to make a comparative analysis of the bacterial species involved in the degradation processes of cellulose-containing waste and to assess their potential for possible application in space conditions, including the International Space Station.
Keywords: cellulose-containing waste, biodegradation, microorganisms, life support systems, long-term manned space missions

doi.org/10.32006/eeep.2022.2.6872
REGIMES FOR CLOSE-TO-NATURE MANAGEMENT OF THE HIGH-MOUNTAIN PASTURES ON THE TERRITORY OF BELASITSA NATURE PARK
Slavcho Savev
University of Forestry, Sofia, Bulgaria
Abstract. The high mountain and subalpine treeless part of the territory of Belasitsa Nature Park is occupied by herbaceous and shrub communities. Almost the entire part of the mountain roof is represented by a natural habitat 4060 "Alpine and boreal ericoid communities", with Siberian juniper being the dominant species in the communities. The current state of the vegetation resulted from the lack of economic activities in the treeless area in the last 25 years. Surveys to date have revealed significant change resulting in a reduction in the total area of grassland habitats as a result of colonization with ericoid scrub. Considering the trend of natural succession processes, the management in this area should focus to the restoration and maintenance of grass vegetation except in places with species of high conservation value. In this case, grazing can be a natural tool slowing down this undesired succession. The grassland communities in the highlands of our mountains are semi-natural and this tool could prevent them from becoming entirely juniper scrub, which would result in the loss of remaining natural habitats of conservation value. Research data show that in the past, the load of livestock to the pastures in the area was less than their capacity, i.e. pastures in the park have not been overcrowded. This fact indicates that more intense use of the pastures in the future will not provoke a danger of disturbing plant diversity. Habitat 4060 in Belasitsa occupies an area of 1023.97 ha, or 98% of the total 1037.48 ha of treeless high mountain area, with the remaining 13.51 ha being pastures of conservation importance. The grasslands of conservation importance are represented by three types of natural habitats, which, as a result of juniper succession, are highly fragmented, represented by several separate small areas of several hectares each. Two areas for pastures have been designated along the land borders between Samuilovo and Kolarovo. It is recommended that grazing be done on a rotational basis in the two areas.
Keywords: regimes, pastures, conservation management, succession.

doi.org/10.32006/eeep.2022.2.7378

ASSESSMENT OF THE EXPECTED INDUCED RADIOACTIVITY IN THE BUNKER WALLS AT THE INRNE-BAS CYCLOTRON FACILITY

Anguel Demerdjiev, Dimitar Tonev, Nikolay Goutev, Dobromir T. Dimitrov, Galina D. Dimitrova, Elena Geleva, Stefan G. Genchev

Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences

Abstract. The Institute for Nuclear Research and Nuclear Energy at the Bulgarian Academy of Sciences is working on the construction of a cyclotron centre. Оne of the challenges in designing the radiation protection of a cyclotron centre is the preliminary assessment of the expected amounts of radioactive waste that will be generated during the lifetime of the facility. Our aim in this paper is to make an estimation of the expected induced radioactivity in the cyclotron bunker walls after the 20 year operational period of the facility. For this purpose, Monte Carlo simulations with the code FLUKA were performed. The distributions of the specific activity of the generated radionuclides in the concrete walls and of the residual dose rates inside the bunker are obtained. The specific activity of the most important long-lived radionuclides in the concrete walls of the bunker, namely ¹⁵⁴Eu, ¹⁵²Eu, ¹³⁴Cs, ⁶⁰Co, ⁵⁴Mn is estimated. On the basis of these results an optimization of the shielding design is proposed in order to decrease the amount of radioactive waste which will be generated during the facility lifetime.
Keywords: TR-24 cyclotron, Radioactive waste, Monte Carlo simulations, FLUKA

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