Yearly Archives: 2019

Abstract:

The hygiene process imposes a high usage of household cleaning products and personal care products, which after use reach the municipal and industrial wastewater of the sewerage networks and finally the surface wa ters. Depending on the physic, chemical and biological properties of the constituent substances, they could manifest various harmful effects on the aquatic organisms such as mortality, inhibition or stimulation of growth / development, and changes of the community structure linked to particular ecosystems and water quality degradation. The study objective was to highlighted the aquatic toxicity effects of some cleaning products on freshwater fish, green microalgae and planktonic crustaceans in order to corr espond to EU ecolabel criteria. Three products based on anionic, non ionic and amphoteric surfactants were tested using OECD methodologies. The laboratory experiments showed non toxic acute effects on tested organisms. The acute toxicity concentrations (EC 50 / LC50) being more than 100 mg/l for each tested product. Acording to international norms for toxicity clasification all the products were non harmful for aquatic live.

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Abstract:

Contemporary Project Management has conceived tools based on mathematical models for planning, scheduling and controlling the projects, the costs and resources. Critical Path Method (CPM) and Program Evaluation and Review Technique (PERT) are two network-based methods which were independently developed to assist the project managers in order to schedule complex real-life projects. A scheduling of a small-scale R&D project using these optimization time-oriented methods was accomplished. In many models of project network some activities are closely related to each other such as procurement activities of basic resources and research activities. If this precedence relationship is on the critical path, that means whitout no event slack or float time for activities, then some procurements delay may cause lag in the project’s completion time. Thus a good estimation for procurement and research activities duration is needed for a Just-in-Time project.

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Abstract:

In this article results of studying of an environmental problem as pollution of the soil at use of mineral fertilizers are proved against the background of traditional technologies of cultivation of soy. A comparative assessment of efficiency of resource-saving technology with the studied norms of mineral fertilizers in optimization of an ecological situation of an agroecosystem is given. At traditional technology it is revealed that use of the increased norms of N60P180K90 causes increase in level of impurity of the soil heavy metals and decrease in efficiency of the cultivated culture of soy. The value of resource-saving technology in rational use of bioenergy potential of an agroecosystem is revealed and elements of intensive technology with lower norms of mineral fertilizers for increase in efficiency of an agroecosystem of soy are chosen. It is proved that mineral fertilizers are one of the main factors of stabilization of an ecological condition of the soil, providing increase in efficiency of soy at resource-saving technology of cultivation in the conditions of irrigation of the southeast of Kazakhstan. Application evidence-based resource-saving receptions with elements ecologically safe intensive allows to support technologies rather quickly stability of an agroecosystem.

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Abstract:

A good function of waste-to-energy installation requires knowledge of the combustion characteristics of the fuel and fusion characteristics of the ash produced in the combustion process. Sewage sludge could be considered as renewable fuel due the high quantity of organics of sufficiently high calorific value. The combustion of sewage sludge can cause operating problems due to high ash content containing mineral compounds. This paper presents the oxide composition of three kinds of sewage sludge ashes and the influence on the slagging and fouling process in combustion. For comparation, two coal samples were selected, a low and a high rank coal. The mineral matter were investigated by the X-ray fluorescence analytical technique using the Rigaku CG X-ray Spectrofluorimeter. The evaluation of slagging and fouling process was performed on the basis of some indices: the basic oxides, the base-to-acid ratio, the slagging index and the fouling index. The conclusion based on experimental studies is that depending on mineral content the sewage sludge ash can cause high to moderate slagging and fouling hazard.

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Abstract:

Black Sea represents a direct link between the European Union, EU candidate countries and some Asian countries such as Russia, Georgia, etc. During the last decades, the Black Sea has been confronted with unexpected environmental problems. In the south part of the Romanian seashore has appeared erosion, in the North-East part of the Black Sea appeared a massive algae development, followed by modification of the maritime biological balance. In parallel, the maritime water parameters have been changed, partly due to the water discharged from the main rivers as Danube, Dnieper, Dniester, partly from the amount of freshwater from deep currents new appeared in the last decades, and partly due to the impact of the pollutant sources. Firstly, are mentioned some data, based on the local measurements and registered data, which underlines the actual situation, referring at the existing sources of pollution, the hydrocarbons and ions concentration, etc. with immediate consequences on the local equilibrium of the marine bio-system. The registered Turkish accidents with spilled oil briefly mentioned, were followed in a short term by a process of nitrification, with many consequences. Next are presented the appeared modifications, registered in the Black Sea fauna, some endangered species, correlated with the simultaneous apparition of some invasive species. Finally, some conclusions and references are presented.

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Abstract:

The paper presents the influence of pH on the dissolved organic carbon in industrial waste samples as a decision indicator in determining the hazardousness of the waste at storage according to the environmental legislation. Waste storage is a common method of management and is realizing according to GO 95/2005, which requires limit concentrations of the indicators analyzed according to each type of deposit (inert, non-hazardous, and hazardous). For the analysis of the dissolved organic carbon, 6 samples of waste from different sectors of activity were subjected to the leaching test and the eluate was analyzed on a multi N/C 3100 equipment at both the pH of the waste, itself and between 7.5 and 8 pH units. From the results obtained it is found that the modification of the pH leads to significant variations in the concentration of the dissolved organic carbon, variations which can provide essential information for the subsequent management of the waste.

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Abstract:

A methodology for quickly and easy determination the quality of pellets offered on the market is developed on the basis of “theory of graphs”. The pellet quality assessment is performed in two ways – by direct control (non-destructive measurements) and by combustion. The following pellets parameters are determined at the direct control stage: friability, homogeneity, presence of dark stains and moisture content. The experimental measurement of following parameters of the combustion process is carried out at the stage of pellet burning assessment under real conditions: temperature in the combustion chamber, time for complete combustion of the pellets and the amount of ash after pellets combustion. The calorific value of the tested pellets is determined on the basis of the experimentally obtained parameters of the combustion process. The the obtained parameters values are statistically processed according to the described in the paper equations at the next stage. Then the results for the investigated pellet parameters are compared with the normative values. The proposed methodology could be calibrated by experimental determining the calorific value of investigated pellets by a calorimeter. Practical application of this methodology is that by not so complicated measurements and calculations the required amount of pellets for heating a building with a certain energy consumption for heating season could be determined.

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Abstract:

The main objective of the study, presented in the article, is to review the possible methods of final recovery of End-of-Life Tires (EOLT). Applied methods of the end-use of EOLT used in Republic of Bulgaria and in some other countries in the European Union are presented and commented in the paper. Also the end-use of EOLT waste criteria is discussed. The possibilities for post-recovery including recycling of the waste generated by the tire recovery process have been explored. The application of the identified methods in Republic of Bulgaria and other European Union Member States have been analyzed and assessed.

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Abstract:

The most commonly used insulating liquid in transformers is mineral oil. Special synthetic applications such as silicone, ester, perchloroethene, etc. are used today in special applications, with different characteristics, very low or nonexistent toxicity to mineral oils used in transformers. On the other hand, they have a much better biodegradability than mineral oils in both aerobic and anaerobic conditions. But they cannot directly replace the mineral oil in operation or in repaired units. They have dielectric properties and good heat transfer but have limited their use to special transformers due to the relatively high cost and availability.

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Abstract:

Climatic conditions from areas where vine is cultivated or intended to be cultivated are essential and important to be acknowledged especially in the context of climatic changes that have taken place during the last 50 years. In this regard, prevention solutions are recommended to be implemented as well as solutions that decrease the damages caused by climatic changes or other stress factors. Among these solutions we mention the reorientation of vine areas, planting shelter-belts in areas and regions exposed to high intensity winds, reconsidering the structure of viticultural varieties or selecting the cultivated vine varieties.

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Abstract:

The publication deals with the development of a structural model of payment schemes for ecosystem services (PES) oriented to usage of forests for water, soil and microclimate quality improvement. Proposed structural model is built on the Meta analyses base of more than 50 PES schemes worldwide. The proposed structural model has three top down levels – groups of categories, categories and attributes. There are seven groups of categories, 17 categories and more than 120 attributes. The structured information about studied PES schemes is stored in a warehouse managed by unique web platform created by the authors. An important part presented study is the developed generic use case of PES schemes with definition of seven participated actors.

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Abstract:

For environment protection in the European Union (EU) it is very important the construction waste to be recycled and reused. The potential for the construction waste recycling and reuse is high, as their components have high cost. There is an opportunity for re-use of such materials in road construction, for drainage systems, for outdoor sports grounds and other construction sites. In 2012 a regulation on the management of construction waste and on the use of recycled building materials was adopted in Bulgaria, aiming to introduce a new model for the management of construction waste. This would guarantee: creation of favorable legislative and economic conditions for implementation of technologies ensuring the achievement of recycling and recovery targets but which are also financially viable in line with the country’s incomes; identifying the persons responsible for covering the costs of building waste management and achieving the recycling and recovery targets; creating conditions for the production and marketing of materials from recycling of construction waste at a price that is competitive with the same new raw materials used in construction. The main effect expected from this normative document is to contribute to Bulgaria’s development towards European trends, 

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Abstract:

Particulates generated by anthropogenic activities are found in the ambient air in varying amounts, in a wide range of sizes and in a wide variety of chemical composition. The concentration of particulates at one site, as well as their composition, are influenced by their origin and dispersion factors. By chemical and dimensional analysis of particulates in an area, we can draw preliminary conclusions about the origin and level of pollution in that area. This paper presents the results obtained by concomitant monitoring of particulates emissions and the concentration of particulate matter in ambient air in the adjacent area of an industrial plant. The result of the measurements obtained and their correlation with the specific conditions during the monitoring period lead us to the conclusion that the concentration of particulate matter at the emission sources directly influences the concentrations of particulate matter in the neighbouring area.

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Abstract:

Lead, a high-risk environmental pollutant and extensively used by industry, is one of the most widely outspread toxic metal today. Lead toxicity is a public health problem both for the children and for the adults. Lead does not have any useful functions in the body, instead it produces only harmful effects once it gets into the body. In this study, we investigated the toxicity of lead in an animal model of non-acute exposure. Experimental groups received treatment of aqueous solution lead acetate at different doses and time of administration. Toxic effects of lead were investigated on haematological and behaviour of treated rats. We noticed the disturbances of both haematological parameters and behaviour. Our results indicated that non-acute exposure to lead induced toxic effects in the blood, and central nervous system of adult Wistar rats.

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Abstract:

The main activity of the studied company is treatment and coating of metals (galvanizing plating), trapping and treatment of waste water. Galvanizing consists in creating a superficial diffusion layer of iron alloy. BATs (Best Available Techniques) do not necessarily mean the most advanced technique available, but the best technique from an economic point of view for a particular installation. Results of the research relate to compliance of the industrial water treatment plant to BAT best available techniques, in order to minimize pollutants discharged into the sewerage network. Furthermore, the current paper identifies possible dysfunctional problems of the galvanizing plant and of the sewage treatment plant and makes suggestions of remedies for possible technical and organizational problems.

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Abstract:

The waste management strategies released and applied in EU countries endeavor to achieve the improvement of natural resources use and efficiency towards reducing the air, water and soil pollution due to improper waste disposal or treatment. This paper is a blueprint on waste generation and waste management Policies, Laws and strategies existing in Romania compared to EU countries. According to Directive 2008/98/EC Waste, is defined as “any substance or object which the holder discards or intends or is required to discard”. One of the main principles of waste management strategies is to be able to process the waste generated towards reaching as up as possible the Waste Management Hierarchy. From the circular economy concept point of view, the incorrect treatment of waste is representing an important loss of resources, both in raw materials and energy and therefore recycling and reuse should reach a superior level every year.

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