Methods and tools for environmental technologies risk evaluation: the principal guidelines—a review

The commonly used and developing engineering environmental technologies do not remain neutral for an ecosystem. The deepening climate changes are generally considered as the effects of human activities. There is thus no doubt that any human interference in the environment should be comprehensively checked at the beginning for all its positive and negative aspects for the environment as well as society health. There are two different analytical tools useful in environmental management: life cycle assessment (LCA) and risk assessment (RA). The first follows the product from “from birth to the grave” summing the environmental impact at all stages of its “life” including such elements like producing, used electricity, transport and many others. LCA refers to quantification and classification of all effects at all life stages and provides direct and indirect possible environmental interactions. On the other hand, risk assessment focuses on linking stressors and its possibilities and severity. RA tools reveal environmental and human health impacts of strictly separated elements, providing insight as to which emission consists of an important threat. This paper is focused on summarizing two the most used methods and tools for supporting the decision making process in use of environmental engineering technologies. In this paper, the fundamental differences between LCA and RA and benefits from their use has been contained.

The Thermoelectric Properties of Monolayer MAs2 (M = Ni, Pd and Pt) from First-Principles Calculations

The thermoelectric property of the monolayer MAs2 (M = Ni, Pd and Pt) is predicted based on first principles calculations, while combining with the Boltzmann transport theory to confirm the influence of phonon and electricity transport property on the thermoelectric performance. More specifically, on the basis of stable geometry structure, the lower lattice thermal conductivity of the monolayer NiAs2, PdAs2 and PtAs2 is obtained corresponding to 5.9, 2.9 and 3.6 W/mK. Furthermore, the results indicate that the monolayer MAs2 have moderate direct bang-gap, in which the monolayer PdAs2 can reach 0.8 eV. The Seebeck coefficient, power factor and thermoelectric figure of merit (ZT) were calculated at 300, 500 and 700 K by performing the Boltzmann transport equation and the relaxation time approximation. Among them, we can affirm that the monolayer PdAs2 possesses the maximum ZT of about 2.1, which is derived from a very large power factor of 3.9 × 1011 W/K2ms and lower thermal conductivity of 1.4 W/mK at 700 K. The monolayer MAs2 can be a promising candidate for application at thermoelectric materials.

Production of Purified Methane and Bio-Fertilizers by Anaerobic Digestion of Food Waste

Anaerobic digestion is a biochemical process in which the organic substances are digested by microorganisms to methane (biogas) and carbon dioxide in the absence of oxygen. This process is spontaneous but the control on large scale requires good knowledge. The search for appropriate models of this entire system of bio gas production with filtration process by benefitting the society, improving world’s economy, and protecting the environment at the same time making biogas as a sustainable energy resource is covered. The aim of this paper is filtration of raw bio gas and methane production in all economic aspects. For this, a low costbio gas system by separating the other gases from methane, called chemical scrubbing was developed. Purified methane obtained can be used in various fields as domestic and industrial (cooking, electricity, transport and other power application).

Infrastructural Development, Agricultural Output and Employment in ECOWAS Countries

Data from 15 ECOWAS countries from 2000-2017 were generated from World Development Indicators and Africa Infrastructure Development Index. Variables of concern are agricultural output, agricultural sector employment, access to electricity, transport, ICT, agricultural land, economic growth and FDI.

Infrastructural Development, Agricultural Output and Employment in ECOWAS Countries

Data from 15 ECOWAS countries from 2000-2017 were generated from World Development Indicators and Africa Infrastructure Development Index. Variables of concern are agricultural output, agricultural sector employment, access to electricity, transport, ICT, agricultural land, economic growth and FDI.

Regulación y uso de las redes de transporte y distribución de electricidad

LABURPENA: Garraio-sarearen eta elektrizitate-horniduraren erregulazio juridikoa garrantzi handiko gaia da jardueren banaketa bertikalaren printzipioan inspiratutako merkatu elektriko liberalizatuaren sorreran. Sarearen izaera monopolistak, ezinbesteko baliabidea izanik, erabiltzaileak sare horretara iristeko eta konektatzeko legezko arau batzuk mugatzea ekarri du, objektibotasun-, gardentasuneta diskriminaziorik ezaren irizpideetan oinarrituta. Ikerketa honek, alde batetik, hirugarrenak sarera sartzeko oinarria jorratuko du, eta, ondorioz, sare-kudeatzailem independenteak eratzeko beharra. Bestetik, sarbide-arloan indarrean dagoen araubide juridikoa jorratuko da hemen, gobernuak sareetara iristeko eta konektatzeko baimen-sistema berria arauz garatzen ez duen artean (Sektore Elektrikoari buruzko Legean iragarrita dago erregulazio hori). Era berean, azken urteotan sarbidearen esparruan agertu diren gatazka nagusiak aipatuko dira. RESUMEN: La regulación jurídica de la red de transporte y distribución de electricidad es un tema trascendental en la creación de un mercado eléctrico liberalizado inspirado en el principio de separación vertical de actividades. El carácter monopolista de la red, por tratarse de un recurso esencial, ha conducido a la delimitación de unas reglas legales de acceso y conexión a ésta por parte de los usuarios, en base a criterios de objetividad, transparencia y no discriminación. El presente estudio aborda, de un lado, el fundamento de este acceso de terceros a la red y, en consecuencia, la necesaria configuración de unos gestores de red independientes y, de otro, el régimen jurídico vigente en materia de acceso en tanto el gobierno no desarrolle reglamentariamente el nuevo sistema de permisos de acceso y conexión a las redes, ya anunciado en la Ley del Sector Eléctrico. Asimismo, se hace mención de los principales conflictos de acceso acaecidos en los últimos años. ABSTRACT: The legal regulation of the electricity transport and distribution network is a trascendental subject in the creation of a Deregulated Electricity Market inspired by unbundling. The monopolistic structure of the network, as an essential resource, has defined rules of access and connection to the network by the users, based on criteria of objectivity, transparency and non-discrimination. In the present study, on the one hand, we discussed the legal basis of third-party access to the network and, consequently, the necessary configuration of the independent network managers, and, on the other hand, the current legal system with regard to access, whilst the government does not develop the new system of access and connection permits to the networks, already announced by the Electrical Sector Law. Additionally, there is specific mention of the main accessconflicts what has happened in recent years.

Models of Objects of Control in SCADA System for Monitoring and Operational Dispatching in Sofia Metropolitan

Supervisory Control and Data Acquisition systems (SCADA) are often used in some important industry sectors, such as production and distribution of electricity, transport management, etc. The purpose of this paper is to establish models of SCADA system, DISIM that is incorporated into the Central Dispatching Station of Sofia Metropolitan. Its functions are related to remote visualization and management of the structures and devices in both directions - Trains operation (DISIM-V) and Power transmission system (DISIM-Å). The suggested structural models and mathematical description are used as a basis for realization of a simulator of both SCADA systems

Safety Aspects of the Renewable Sources of Materials and Energy – Biomass Processing

The anticipated increase in the demand for wooden biomass for the production of pellets requires focusing attention on the issue of safety and health protection at work as well as application of modern machinery to minimize the risk of injury or damage to health. Biomass gasification is a promising technology, which can contribute to develop future energy systems which are efficient, safe in design and operation as well as environmental friendly in order to increase the share of renewable energy for heating, electricity, transport fuels and higher applications. Biomass gasification is ready for commerce but today large-scale introduction is hampered by various reasons. Health and Safety issues are recognized as a major barrier in the deployment of this technology.