Papers by Keyword: Life Cycle

Abstract: The resource intensity of primary nickel production in China was analyzed by the indicator of exergy, which can provide a unified picture about the overall processes involved in the life cycle of nickel. The results show that primary nickel’s CExD value is 235GJ_ex/t, and the largest contributor to the CExD is electricity (46%), followed by fuels (31%), mineral (16%), and land resource (7%); the considerable proportion natural mineral and land resource account for in the result is due to the high exergy value of sulphide minerals and the low grade of natural nickel ore. The results also show that the calculation of this study is sensitive to the choice of allocation basis (mass and market value); however, market value is not recommended in this study since that nickel’s price varies greatly over time.

Abstract: In order to determine the optimal parameters of the external insulation system and guide the energy saving and greenhouse gas emission reduction of building, a typical student dormitory building in Beijing was chosen as research object. The life cycle thinking and dynamic simulation method were used in the present investigation. The relationship between the expandable polystyrene (EPS) external insulation system design parameters and building energy consumption and greenhouse gas emission in each phase of materials production phase, operation phase and the whole life cycle was studied, systematically . The results show that the consumption of clay brick, concrete and cement mortar account for 98.1% of the total materials consumption, where concrete contributes most to both energy consumption (36.6%) and greenhouse gas emission (35.9%). Regarding the contribution to energy consumption and greenhouse gas emission for building life cycle, materials production phase accounts for 5.6%-18.8% and building operation phase takes up 80.6%-93.4%. With the increase of EPS insulation thickness, the energy consumption and greenhouse gas emission increase linearly in materials production phase, decrease in building operation phase, and have an optimization value in the building life cycle to reach the minimum when the heat transfer coefficient (K) is 0.3W / (m² • K) equivalent to the EPS insulation thickness is 130mm. Building heating load reduces with the increases of insulation thickness, but the envelope thermal insulation performance has no significant influence on cooling load.

Abstract: In connection with the significant volume of polystyrene embedded in buildings as thermal insulation, in the next few years it will be needed to solve the matter of its disposal after the end of its life cycle. Hexabromocyclododecane (HBCDD) has been used as a flame retardant in polystyrene thermal insulation (EPS and XPS) for the last 50 years. The internationally recognized Stockholm Convention on Persistent Organic Pollutants prohibits future production, use and recycling of materials that contain HBCDD. It also, to a large extent, limits the options of waste management of such materials. European legislation, in particular Regulation (EC) No 850/2004 and the so called REACH Directive, established a binding legal framework for EU Member States which reduces waste management options of material containing HCDBB practically only to incineration. In the coming years, this fact requests fundamental changes in disposal of construction and demolition waste containing the polystyrene insulation and related processes on construction sites in the Czech Republic. The research is based on the analysis of the international and the Czech legislation related to this issue, and the analysis of material and technological context. The paper focuses on possible operational, economic, energy and environmental impact on the construction industry and environment, and compares the current situation in the Czech Republic with other European countries, and assesses the readiness of the Czech Republic to deal with the upcoming legislation changes.

Abstract: This paper presents an original work about the calculus of fatigue resistance to limited durability for a desmopan membrane, a thermoplastic polyurethane membrane. For this research we needed the values of stresses, determined by Finite Elements Method (FEM). In order to apply FEM, we needed mechanical characteristics of thermoplastic polyurethane membrane, characteristics that have been determined by Digital Image Correlation Method. Mechanical characteristics and geometrical characteristics, with loadings too, are input for FEM soft. The calculus of fatigue resistance to limited durability serves to reliability studies of the thermoplastic polyurethane membranes, that diaphragm pumps are equipped.

Abstract: The article considers the rules of constructing machining operations in terms of impact of the product lifecycle to choose operating sizes. A comprehensive optimality criterion is proposed. Technology combined method of surface hardening mixtures based on thermal impurities and its perspective value are shown.

Abstract: The approach to managing the lifecycle of electrical equipment based on genetic algorithms is considered in this paper. The distinction of the approach is in the use of genetic simulation methods regarding the effective maintenance of electrotechnical equipment. The interpretations of genetic operations in such approach are given. The function of the life cycle of electrotechnical equipment is introduced.

Abstract: Impacts of production, operation and use of a building on the environment and society cannot be ignored in design any more. Instead, performance and impacts of a building needs to be considered for a lifetime, established by design rules 50-100 years. Steel, as constructional material, plays an important role as a component for buildings and engineered structures, with a wide range of applications. Like other industrial activities, steel industry works continuously to improve in terms of sustainability. In fact, in can be observed that in the last decades, the steel frames houses, as an alternative to houses made of traditional materials, offers a lot of advantages in terms of sustainability. The approach in term of a life cycle for a building is an objective process for the evaluation of the impact on the environment, associate to a production process or to an activity. These approaches are recommended by the Integrated Product Policy (COM2003) for the evaluation of the potential impact of the products In present, there are 2 majors categories instruments for the evaluation of the built environment, on one hand made on qualitative instruments based on criteria and score, and on the other hand instruments that use an quantitative analyze of the inputs and outputs based on a life cycle. Some of these methods are used for the certification of buildings as “green-buildings”. Even many parameters are usually quantitative; they can be also qualitative in the same time, when we try to quantify the advantages due to materials.

Abstract: The paper analyses the possibility of alkali activated materials utilization as matrix for repair mortars, determined for rehabilitation of reinforced concrete structures, exposed to chemically aggressive surroundings. alcali activated materials have owing to their specific properties a high potential especially for utilization in materials determined for specific applications. Materials showing in comparison with the cement matrix significantly higher resistance against the effect of chemical substances are the so-called alkali activated materials. The rehabilitation of reinforced concrete structures exposed to extreme conditions is the area for effective utilization of the alkali activated extraordinary properties.

Abstract: Over the past several decades with significant technological advances there has been continuous increase in plastic manufacturing in China, which has contributed to the production of a great deal of plastics worldwide every year, and at the same time it has resulted in a large amount of plastic solid waste (PSW). It has great potential values for waste plastics to reuse as secondary materials, which may lessen pressure on resource and environment. The paper studies the status of waste plastics in recycling, reusing and reducing on management countering on the increase in the flow of waste plastics in Shanghai. In light of the methodology of life cycle, the study analyzes the environmental impacts associating with the alternatives in a ‘cradle to grave’ approve to PSW technological recycling systems. We will choose regenerating and energy recovery processes based on site investigation and literatures data in Shanghai to analyze recycling options and how various processes affect the environment. Life-cycle methodology was very suitable for evaluating the overall environmental consequences, and could be used for making decisions and planning strategies with the rapid increase of plastic solid waste generation for Shanghai.

Abstract: The paper deals the possibility of alkali activated materials utilization as matrix for repair mortars, determined for rehabilitation of reinforced concrete structures. Alkali activated materials have owing to their specific properties a high potential especially for utilization in materials determined for specific applications. Materials showing in comparison with the cement matrix significantly higher resistance against the effect of chemical substances are the so-called alkali activated materials. One of the essential conditions for the successful use of repair mortars is their sufficient cohesion to the surface respectively with the surface of rehabilitated structures.