0000000000132706
AUTHOR
Marius Bibu
Determining the explosion risk level and the explosion hazard area for a group of natural gas wells
Starting from the fact that the natural gas engineering profession is generally associated with a high occupational risk, the current paper aims to help increase the safety of natural gas wells and reduce the risk of work-related accidents, as well as the occurrence of professional illnesses, by applying an assessment method that has proven its efficiency in other industrial areas in combination with a computer-aided design software. More specifically, the paper focuses on two main research directions: assessing the explosion risk for employees working at natural gas wells and indicating areas with a higher explosion hazard by using a modern software that allows their presentation in 3D. Th…
Studies concerning the decontamination of hydrocarbons- polluted soil areas using bioremediation techniques
The accidental or historic contamination of soils with hydrocarbons, in areas crossed by oil pipelines or where oil- or gas-extraction installations are located, is a major concern and has significant financial and ecological consequences, both for the owners of those areas and for the oil transportation or exploitation companies. Therefore it is very important to find the optimal method for removing the pollution. The current paper presents measures, mainly involving bioremediation, recommended and applied for the depollution of a contaminated area in Romania. While the topic of dealing with polluted soils is well-established in the Romanian speciality literature, bioremediation is a relat…
RESEARCHES ON THE DIGESTERS AND REACTORS WHICH CAN BE USED IN A FARM SCALE BIOGAS PLANT
In the general context of searching integrated system of renewable energy production, this paper present some researches on the reactors and the digesters, as a main part of a biogas plant at a farm scale. After we present the most used types of digesters, we also concentrated over the processes which take place into a digester, one of them being the removal of H2S from biogas (desulphurisation), which can be made by various methods, either biological or chemical, taking place inside or outside the digester. In the case of biological desulphurization outside the digester, we concentrate on the types of reactors which can be used in this case. Beside the well known types of reactors, we pres…
Metallographical Aspects of the Application of Special Paint Layers for the Protection of Machine Part Sections against the Effect of lonitriding
The paper presents aspects concerning the appreciation of the protection through special paints based on copper powders used against plasma nitriding. First of all the choice of copper is motivated as an important metallic component of protecting paints, with the characteristics that the copper presents in the context of the physical and chemical phenomena (from the cathode and from gas volume) specific for the ionic nitriding process. The paper contains comparatively some characteristics (the duration of drying on the coat, the compatibility of the components, the capacity of extension and of avoiding the leakage, the power of covering, the capacity of joining, and the emitting of gases, t…
Analysis of the road traffic-induced pollution in two areas of Sibiu, Romania
The current paper details a computer-aided research of the emission levels in two areas of the city of Sibiu, Romania. The research started from the numbers of motor vehicles passing through key segments of those two areas, located at entry points into the city of Sibiu. Using the software package Synchro Studio 7 and SimTraffic 7, the targeted crossroad areas were modelled and key indicators for the road traffic efficiency and for the emission levels were determined. These emission levels were then compared to real measured pollution values, which allowed both to assess the accuracy of the modelling and the influence of other pollution sources on the emission levels in those areas.
STUDIES AND RESEARCHES CONCERNING THE POSSIBILITY OF USING HYDROGEN IN TURBO ENGINES
The paper aims to study the main aspects related to using Hydrogen as fuel in thermal engines, the advantages and disadvantages of using it as fuel and the technical posibilities of adjusting it, Hydrogen used as supplement at the main fuel and Hydrogen used as working fluid. As a perspective, it can be considered using Hydrogen as thermical agent in a closed energetic flux with thermo- chemical compression of Hydrogen in a hybrid heat changer, based on the heat of burning products of thermical engines. The experiments made showed that using such a way of using the heat of burning products of turbo engines can assure the increase of power and efficiency of the whole instalation with 20 %, w…
Aspects of Improving the Cost-Performance Ratio for the Manufacturing of Small-Size Cast Parts
Abstract The paper analyses some of the commercially available solutions for casting small-size metallic parts and outlines possible solutions that would reduce the cost of such systems while maintaining a high performance level. high performance level. One typical application area for small-size parts is human prosthetics, so the commercial casting machines analysed here are used mainly in this application domain. The paper shows how high-cost systems added to the machines for providing protective atmospheres can be replaced by low-cost solutions with the same results in terms of part quality. Moreover, a solution is described that avoids the typical drawbacks of the currently used casting…
Changes of Structure and Physical-Mechanical Properties in Alloy Steels Thermochemically Treated by Plasma Nitriding
Plasma nitriding is a method of surface modification using a glow discharge technology to introduce nitrogen into the surface of a metal, which subsequently diffuses into the material. The main advantages of plasma nitriding over conventional nitriding processes are: reduced cycle time, controlled growth of the surface layer, elimination of white layer, reduced distortion, no need of finishing, pore-free surfaces and mechanical masks instead of copper plating. The process is especially suitable for complex parts that are intensively solicited by wear, fatigue, contact pressure, shocks, possibly also to corrosion. It is applied in order to bring the metallic products in a state favourable fr…
Ionic Nitriding of Certain Parts Protected on Nonfunctional Surfaces With Special Paints. Electric Energy Consumed
The experimental researches on the promotion of new technologies for the local protection of metallic parts against plasma nitriding, led to two types of special paints for protection in ionic nitriding, paints elaborated on the basis of copper lamellar powder in combination with magnesium oxide and carbon tetrachloride. In the created context, it was considered that the elaborated paints could be used not only for preventing the hardening during ionic nitriding of certain technological surfaces of the parts on which they are applied, but also for coating certain nonfunctional surfaces, their degasification taking such a long time. These nonfunctional areas could be: surfaces resulted from …
Assessment of metallic materials required for shock stress protection
Establishing which metallic materials are suitable to be used for the protection of operators and machinery, when subjected to stress impact in the drilling industry, for surface exploitation, mines and quarries, is a complex process. Due to the harsh operating conditions, a careful evaluation of the various materials used is of utmost importance. This paper addresses the issues relating to the methodology of determining the appropriate homogenous materials to be used, based on a correspondence between their characteristics and applications. Starting with a list of specific operating conditions, one has established a set of requirements and has assessed the market; the recommended materials…
Computer-aided study of the gas flow within a natural gas storage and the associated collection network
The current paper presents a computer-aided analysis of the way in which a natural gas storage created in a depleted gas deposit and the associated gas collection network are operated, both during the extraction phase and during the injection phase. In a first step, an analysis is carried out on a two-dimensional, nonstationary model for the gas storage, based on the deposit’s geometry and the rock properties, but also on the gas motions. Also, a dynamic simulation of the injection and extraction processes is unfolded, allowing the study and optimisation of elements such as well placement and gas flows through the wells with the goal of maximising the storable gas quantities. A second model…