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Modernizing and increasing performance of Building Services

Abstract

In the present era of continually increasing energy demand, Europe faces many challenges, such as high and unstable energy prices, growing global energy demand, increasing threat of climate change, sluggish progress within energy efficiency and issues related to increasing demand for the use of renewable energy sources. It is desirable to seek opportunities to use energy consumed most reasonably, thus ensuring continuous improvement of energy efficiency in the industry. The scope of the research includes reviewing studies in this matter and analysing the most beneficial solutions for the plant. The work aims to assess possible undertakings to modernise the energy management of an industrial plant on the example of Bulten Poland S.A. rationally and profitably for the plant. The work contains an analysis of the profitability of the potentially most beneficial solutions in terms of improving the energy efficiency of the plant. Mentioned in the article solutions, aiming increasing energy efficiency, helped become the plant independent within heating up facilities. Total heat recovery potential in amount of 18 965 GJ is motivation for further activities. This is a great opportunity to reduce significantly carbon footprint (replacing lightening into LED technology reduced CO2 by 206.3 Mg/year) and be more competitive on the market by reducing costs of product.

Abstract

The use of oil fly ash after the recovery of heavy valuable metals was investigated. More specifically, its use, as an adsorbent of dyes from industrial wastewater, was evaluated. Methylene blue was used as a model compound to study the adsorption capacity of the proposed carbonaceous residue from metal recovery treatments. The effects of contact time, initial dye concentration, and absorbent dose were investigated. The maximum amount of dye was adsorbed after one hour. Moreover, 1-3 g of residues were necessary for the removal of 200-1000 mg dm−3 from 0.050 dm3 of contacted solution. The Langmuir isotherm model was in good agreement with the adsorption equilibrium data, indicating a maximum monolayer saturation capacity of approximately 40 mg/g at 25 °C. High abatement efficiencies (up to 99 %) were obtained, and the adsorbed dye was released almost immediately by re-contacting with water. The adsorption capacity was at least four times lower than that of commercially available active carbon. The double treatment of oil fly ash with deionised water and hydrochloric acid allows for the extraction of over 85 % of the vanadium, iron, and nickel content in the ash. However, the negligible or zero cost of solid residues, otherwise disposed in landfills, indicates their potential as a valid alternative. The use of oil fly ash for both recovery of heavy valuable metals and the subsequent removal of dyes from wastewater suggest a zero-waste process.

Abstract

In the year 2016, passive biomonitoring studies were conducted in the forest areas of southern and north-eastern Poland: the Karkonosze Mountains (Kark), the Beskidy Mountains (Beskid), Borecka Forest (P. Bor), Knyszynska Forest (P. Kny), and Białowieza Forest (P. Bia). This study used bark from the tree, Betula pendula Roth. Samples were collected in spring (Sp), summer (Su), and autumn (Au). Concentrations of Mn, Fe, Ni, Cu, Zn, Cd, and Pb were determined for the samples using the atomic absorption spectrometry method with flame excitation (F-AAS). Based on the obtained results, the studied areas were ranked according to level of heavy-metal deposition: forests of southern Poland > forests of north-eastern Poland. Some seasonal changes in the concentrations of metals accumulated in bark were also indicated, which is directly related to their changing concentrations in the air during the calendar year, for instance, the winter heating season produces higher concentrations of heavy metals in the bark samples taken in spring. When deciding to do biomonitoring studies using bark, but also other biological materials, it is necessary to take into account the period in which the conducted research is done and the time when the samples are taken for analysis, because this will have a significant impact on the obtained results.

Abstract

Romania, due to its historical background, has many vestigial belongings to the cultural heritage, out of which the most noticeable (by number, age, architecture, symbolism and representation) are the wooden churches. Under these circumstances the role of the current study is to emphasize certain practical aspects (focused on the need to assess, preserve, restore and valorize) regarding the use of modern technology based on photogrammetry and 3D scanning. The case study was represented by the “Saint Martyrs Constantin Brȃncoveanu and His Sons” wooden church from Oradea Municipality, Bihor County, Romania; the edifice being included on the list of historical monuments ever since 2010. The final goal being to create 3D models for both the exterior and interior of the monument for research, restoration in case of need, sharing for education, entertainment, tourism purposes etc.

Abstract

In the construction process of modern buildings, the aim is to achieve maximum comfort within minimum energy consumption. One of the ways to achieve this requirement is the accurate determination of the volumetric flow rate of fresh air, necessary to ensure the required indoor air quality. This study begins with the experimental determination of carbon dioxide (CO2) concentration in an office room with one occupant performing three types of activities with different levels of physical intensities. Based on these measurements, a methodology for the precise determination of the volumetric air flow rate is presented. This method was compared with another one that takes into account body parameters and is considered in this study as the most accurate. The required outdoor air flow rate for the experimental room was also determined based on the present legislations of five different countries. Comparing all the studied methods and considering as refence the method based on body parameters, it was found that the accuracy of the values is influenced by the physical intensity of the activity and that most methods generally underestimate the amount of required fresh air.

Abstract

Among the important phenomena caused by tunnel excavations, the settlements on the ground surface can be mentioned, which are particularly important for shallow tunnels excavated in urban areas, and especially when passing under residential areas of cities. Numerous methods such as mathematical (numerical and analytical) ones can be used to predict surface settlement. This study was conducted aimed at using modern techniques such as artificial neural networks to analyze the parameters affecting the occurrence of surface settlement during forepoling tunnel excavation. Tabriz Subway project is a good opportunity to examine the effect of forepoling tunnel excavation the surface settlement in a granular soil with average groundwater level offers. None of the performance parameters (such as the features of the forepoling protective umbrella) and the environmental features (such as the geological effects and tunnel geology) establish a unique relationship with the surface settlement, but several factors together do so. In this study, the forpolling tunnel was modeled using Plaxis software and analyzed in various geotechnical conditions (drained, partially saturated and saturated) under static and dynamic loading. Finally, the values of the surface settlements were examined.

Abstract

The increase in Carbon Dioxide (CO2) gas emissions during the production of cement have increased the necessity for the development of eco-friendly sustainable concrete using alternative binders. This research was conducted to study the strength behaviour in terms of compressive and flexural strength of concrete incorporating rice husk ash (RHA) as a supplementary cementitious material. RHA is a potential alternative binder due to its pozzolanic nature but it can partially replace cement to a certain amount, beyond it, the strength decreases making the concrete less viable. Therefore, to strengthen RHA-based eco-friendly concrete, Polypropylene (PP) fibres were used to reinforce concrete. Based on the results, it was observed that 5% RHA achieved higher strength than the control sample, however, a further increase in RHA content resulted in a significant decrease in strength. Concrete with 10% RHA which showed reduced strength was reinforced with PP fibres which resulted in a gain in strength.

Abstract

Monetary concerns in structural schemes cause serious ramifications that may impede the expansion of schemes and impact the entire fiscal conditions of any country. The study highlights the issues of finance procrastinates in construction schemes. Aim to find the prominent issues on finance-related hurdles, which lead to production obstructions and to explore do able resolutions to overcome monetary connected production delays. The date was accumulated via a survey-based questionnaire and followed by the survey-based interviews. The responses were concluded from the amalgamation of clients, advisors, bankers, and brokers in the questionnaire. Brokers’ unsteady monetary conditions. Customers’ weak monetary and trade administration hinders in getting financial support from financers besides inflation were found as the most prominent problems. The outcomes highlight customers have the most significant function in reducing the influence of monetary issues regarding scheme procrastination. Suggestions and recommendations to reduce monetary-related procrastinations are presented accordingly.

Abstract

The Earth’s large amount of thermal energy is virtually an inexhaustible resource often placed too deep in the ground. Making use of this kind of energy is possible in limited areas. In this paper we analysed a GSHP system, in Galati city (Romania), for which we monitored the available thermal energy. For the analysis we used operational reliability theory, the concept of degradation, which in this case means a reduction of the ground’s thermal capacity as a result of continuous exploitation, meaning low temperature of the thermal agent used for transporting the heat from the ground to the primary exchanger of the heat pump. The decrease of thermal energy supply in the ground means that the heat pump wills no longer function properly in order to provide the energy for heating the building. The term time to failure refers to the time when the ground can no longer provide the minimum required energy for the heat pump operation, in terms of energy efficiency. What we want with this approach is to offer a solution in order to control and manage the heat pump operation.