Estimation of the operability of technological systems for the production of biogas by comprehensives indicators

2021 ◽  
pp. 96-105
Author(s):  
M. Potapenko ◽  
◽  
V. Ramsh ◽  
V. Sharshon ◽  
◽  
...  

A promising alternative energy source is biogas, which is obtained by bacteria processing an organic substrate without access to oxygen. The efficiency of the use and functioning of technological systems is determined by the indicators of their operability and reliability. The aim of the study is to develop a methodology for assessing the performance of technological systems for biogas production by complex indicators. The article analyzes the methods of complex assessment of the state of technological systems. The considered methods have the following disadvantages: most of them can be used only after a certain operating time of the system; expert assessments are based on intuition and, as a result, are not always objective; the functional-parametric approach is methodological rather than practical; determination of the efficiency retention coefficient with an increase in the number of elements and the complication of the structure of the technological system becomes rather difficult. The operability of technological systems for biogas production with an increase in their service life is expressed through a change in technical condition indicators, a decrease in productivity and a change in economic indicators: an increase in costs per unit of work performed and additional costs for maintaining a repair and maintenance base. To analyze the technical state of technological systems for biogas production, it is advisable to use a complex operational indicator , which simultaneously takes into account its technical and economic characteristics during the period of operation, that is, the unit costs of ensuring operability through the cost of a unit of production during the service life up to the limiting state. Key words: technological system, biogas, reliability, operability, efficiency preservation ratio, comprehensive performance indicator

Author(s):  
E. N. Shiryaeva ◽  
M. A. Polyakov ◽  
D. V. Terent'ev

Complexity of modern metallurgical plants, presence of great number of horizontal and vertical interactions between their various structural subdivisions makes it necessary to apply a systems analysis to elaborate effective measures for stable development of a plant operation. Among such measures, digitalization of a plant is widespread at present. To implement the digitalization it is necessary to have clear vision about links at all the levels of the technological system of a plant. A terminology quoted, accepted in the existing regulatory documents for defining of conceptions, comprising the technological system. It was shown, that the following four hierarchical levels of technological systems are distinguished: technological systems of operations, technological systems of processes, technological systems of production subdivisions and technological systems of plants. A hierarchical scheme of technological systems of hot-rolled sheet production at an integrated steel plant presented. Existing horizontal and vertical links between the basic plant’s shops shown. Peculiarities of flows of material, energy and information at the operation “rolling” of the technological system “hot rolling of a steel sheet” considered. As a technical system of the technological process of the hot rolling, the hot rolling mill was chosen. A structural diagram of the hot rolling mill was elaborated, the mill being consisted of reheating furnaces, roughing and finishing stand groups, with an intermediate roll-table between them, and down-coilers section. Since the rolling stands are the basic structural elements of the hot rolling mill, structural diagrams of a roughing and a finishing stands were elaborated. Results of the systems analysis of the technological and technical systems, hierarchically linked in the process of steel sheet hot rolling, can be applied for perfection of organization structure of the whole plant, as well as for elaboration mathematical models of a system separate elements functioning, which is a necessary condition for a plant digitalization.


2020 ◽  
pp. 74-78
Author(s):  
A.E. Dreval

The assessment of the limiting state of high-speed machine-manual taps in the processing of structural steel billets is considered. A general multi-parameter dependence is developed for calculating the criterion of allowable wear, which makes it possible to rationally use the tool life and normalize the cut amount during regrinding. Keywords thread cutting, tap, angle of the cutting part, criterion, high-speed steel, wear, failure, life, service life. [email protected]


Author(s):  
O. B. Berdnik ◽  
I. N. Tsareva ◽  
M. K. Chegurov

This article deals with structural features and characteristic changes that affect the mechanical characteristics after different service life in real conditions using the example of the blades of the 4th stage of turbine GTE-45-3 with an operating time of 13,000 to 100,000 hours. To study the change in the state of the material under different operating conditions, determine the degree of influence of heat treatment on the regeneration of the microstructure, and restore the mechanical characteristics of the alloy after different periods of operation, non-standard methods were used: relaxation tests on miniature samples to determine the physical yield strength and microplasticity limit and quantitative evaluation of the plasticity coefficient of the material from experimental values of hardness, which allow us to identify the changes occurring in the microvolumes of the material and predict the performance of the product as a whole.


Energies ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2948
Author(s):  
Soufia Mohammadi ◽  
Pilar Monsalvete Álvarez de Uribarri ◽  
Ursula Eicker

Biogas technology is an important alternative energy source worldwide. Blackwater and kitchen refuse represent ideal waste streams for bioenergy recovery through anaerobic co-digestion. Modeling of the biokinetics of anaerobic digestion on several aspects, such as microbial activity, substrate degradation, and methane production, from co-digestion of black water (BW) and kitchen refuse (KR) was the objective of this research. A mathematical model was developed towards a simulation based on mass balances on biomass, the organic substrate, and biogas. The model was implemented in INSEL and experimental data from the literature were used for model validation. The study shows that the simulation results fit well with the experimental data. The energy consumption and generation potential of anaerobic co-digestion of BW and KR were calculated to investigate if the produced biogas could supply the digester’s energy demand. This study can be used to pre-design anaerobic digestion systems in eco-districts.


Semiotica ◽  
2015 ◽  
Vol 2015 (207) ◽  
pp. 1-29 ◽  
Author(s):  
Andrew Wilson ◽  
Małgorzata Haładewicz-Grzelak

AbstractThe article aims to illuminate the issue of symbolic potential in postmodern society through a semiotic study of car design. In Baudrillard’s terminology, we explore the experience and sociological and psychological materiality of objects that, being above objects’ perceptible materiality, constantly modify the integrity of technological systems (Baudrillard 2005 [1968]: 6). The target concepts are analyzed through Baudrillard’s lens of symbolic capital and his technological system of objects, coupled with the method of semantic differential (SD; e.g., Osgood 1979, 1981) against the insights of Tartu semiotics. Such a complex framework helps to establish affective attitudes of the subjects towards scales selected for their perceptual saliency. The analysis is based on the responses of students in a Polish university who were administered an instrument comprising 14 concepts and 37 scales. The results of statistical analysis yield a semantic space with two factors: potency and activity/dynamism, which we shall call social prestige. At this stage of the analysis we could not determine the evaluation factor. The scales that loaded significantly showed that there is indeed an increment of perceptual saliency in both extracted factors in the case of target stimuli (pickups and SUVs).


Author(s):  
A. Krasheninin

Modern vehicles operated on the railways of Ukraine have almost exhausted or exceeded their resource. The overuse of financial and material resources for their maintenance continues. The standard service life of vehicles was calculated on stable economic conditions of use of vehicles and their timely updating in process of aging. The service life of modern vehicles is determined by the influence of many factors, the disregard of which can lead to significant costs, even in compliance with the standard service life. For railway transport, these factors need modern clarification, as in operation their service life often exceeds the standard or, as for intermodal transport, the service life does not have a strict justification. Accordingly, the article analyzes the issues of assessing the impact on the service life of vehicles of the components of the cost of its maintenance and average daily mileage. It is shown that, firstly, the definition of the service life of vehicles must be linked to the cost of vehicle development, its creation, testing and production, the cost of operation and storage, as well as additional costs, and secondly , with the optimal average daily mileage, at which all the costs are minimal.


2018 ◽  
Vol 19 (12) ◽  
pp. 22-26
Author(s):  
Joanna Rymarz ◽  
Andrzej Niewczas ◽  
Ewa Dębicka

The aim of the article is to compare the operational availability of the city buses. Two popular makes of buses were analysed in the function of time of use, during the six years of operation, in the Municipal Transport Company (MPK) in Lublin. A new division of operating time for the period of full operational usefulness and period of limited operational usefulness of vehicles was presented. It was shown that the average operational availability of the analysed buses differed significantly due to the vehicle's make and also due to the service life. The ANOVA analysis method was used to assess the significance of differences.


2021 ◽  
Vol 894 (1) ◽  
pp. 012013
Author(s):  
M A Budihardjo ◽  
B S Ramadan ◽  
E Yohana ◽  
Syafrudin ◽  
F Rahmawati ◽  
...  

Abstract Municipal Solid Waste (MSW) treatment with anaerobic landfill bioreactor utilizes landfill as a place of biodegradation and produces methane gas which can be used as renewable alternative energy source. Anaerobic landfill bioreactor technology is a landfill development method that can increase waste degradation and increase biogas production. The increase of biogas and the removal of pollutants from leachate needs to pay attention to the factors that influence the success of anaerobic landfill bioreactor, including pH value, temperature, water content, and COD concentration after recirculation, and methane production. The relationship between these factors was discussed in depth in this paper. The method used is a narrative review where metadata is obtained from Google Scholar and Web of Science. This study explains the development of an anaerobic landfill bioreactor and conducts a synthesis for future research development plans by leachate recirculation.


Author(s):  
Dilara Gulcin Caglayan ◽  
Heidi Ursula Heinrichs ◽  
Detlef Stolten ◽  
Martin Robinius

The transition towards a renewable energy system is essential in order to reduce greenhouse gas emissions. The increase in the share of variable renewable energy sources (VRES), which mainly comprise wind and solar energy, necessitates storage technologies by which the intermittency of VRES can be compensated for. Although hydrogen has been envisioned to play a significant role as a promising alternative energy carrier in a future European VRES-based energy concept, the optimal design of this system remains uncertain. In this analysis, a hydrogen infrastructure is posited that would meet the electricity and hydrogen demand for a 100% renewable energy-based European energy system in the context of 2050. The overall system design is optimized by minimizing the total annual cost. Onshore and offshore wind energy, open-field photovoltaics (PV), rooftop PV and hydro energy, as well as biomass, are the technologies employed for electricity generation. The electricity generated is then either transmitted through the electrical grid or converted into hydrogen by means of electrolyzers and then distributed through hydrogen pipelines. Battery, hydrogen vessels and salt caverns are considered as potential storage technologies. In the case of a lull, stored hydrogen can be re-electrified to generate electricity to meet demand during that time period. For each location, eligible technologies are introduced, as well as their maximum capacity and hourly demand profiles, in order to build the optimization model. In addition, a generation time series for VRES has been exogenously derived for the model. The generation profiles of wind energy have been investigated in detail by considering future turbine designs with high spatial resolution. In terms of salt cavern storage, the technical potential for hydrogen storage is defined in the system as the maximum allowable capacity per region. Whether or not a technology is installed in a region, the hourly operation of these technologies, as well as the cost of each technology, are obtained within the optimization results. It is revealed that a 100 percent renewable energy system is feasible and would meet both electricity demand and hydrogen demand in Europe.


2019 ◽  
Vol 11 (1) ◽  
Author(s):  
Wangwang Xu ◽  
Ying Wang

Abstract The increasing demands for environmentally friendly grid-scale electric energy storage devices with high energy density and low cost have stimulated the rapid development of various energy storage systems, due to the environmental pollution and energy crisis caused by traditional energy storage technologies. As one of the new and most promising alternative energy storage technologies, zinc-ion rechargeable batteries have recently received much attention owing to their high abundance of zinc in natural resources, intrinsic safety, and cost effectiveness, when compared with the popular, but unsafe and expensive lithium-ion batteries. In particular, the use of mild aqueous electrolytes in zinc-ion batteries (ZIBs) demonstrates high potential for portable electronic applications and large-scale energy storage systems. Moreover, the development of superior electrolyte operating at either high temperature or subzero condition is crucial for practical applications of ZIBs in harsh environments, such as aerospace, airplanes, or submarines. However, there are still many existing challenges that need to be resolved. This paper presents a timely review on recent progresses and challenges in various cathode materials and electrolytes (aqueous, organic, and solid-state electrolytes) in ZIBs. Design and synthesis of zinc-based anode materials and separators are also briefly discussed.


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