COMPARATIVE ANALYSIS OF THE MEMBRANE SYSTEM WITH LACK OF GAS RECIRCULATION AND SYSTEM WITH GAS RECIRCULATION CONCERNING ENERGY CONSUMPTION OF THE O2/N2 SEPARATION PROCESS IN POLYMER MEMBRANES FOR OXY-COMBUSTION SYSTEMS APPLICATION

Author(s):  
Grzegorz Wiciak
2012 ◽  
Vol 209-211 ◽  
pp. 1068-1072
Author(s):  
Ming Liu ◽  
Bao Gang Zhang ◽  
Liu Wen ◽  
Zhong Zhi Huang

To ensure passengers can have a comfortable thermal environment in the subway waiting room is one of the main targets in subway environment control. By using the CFD software, this paper takes an island platform with double-layer of Shenyang as the object to simulate the thermal environment of platform screen door and ventilation in the open system, then detailed analysis on the variation of the temperature field, airflow velocity field in the typical position. The results indicated that average temperature of no-PSD system platform is 2.5 ~3 °C higher than that of PSD system, standing room is 1.5 °C higher than that of PSD system , but these also meet the requirement of the standards of the environmental control and passengers’ thermal comfort. Meanwhile, through the comparative analysis to the energy consumption of the two systems, we find ventilating condition has superior to PSD system in energy saving, and it is more suitable for the local climate in the northeast.


2012 ◽  
Vol 524-527 ◽  
pp. 3079-3082
Author(s):  
Di Ping Zhang ◽  
Shuang Shuang He ◽  
Gao Qing Li

Taking Zhejiang province as an example, this paper conducted a comparative analysis on the current situation of the energy consumption structure from the vertical and horizontal using the descriptive statistical method. By calculating some indexes such as energy consumption per unit GDP, energy consumption elasticity coefficient, and so on, the study analyzes and evaluates the present situation, trend and influence factors of energy efficiency. Finally, it puts forward some policy suggestions about the optimization of energy consumption structure and energy efficiency.


2021 ◽  
Author(s):  
Dil Rowshan

This study aimed to explore the impact of the Places to Grow Plan 2006 on travel behavior of the work commuters living in GTHA. A comparative analysis was done between the year 2001 and 2011 which represent the situations five year before and after the implementation of the Plan. Data were collected from Transportation Tomorrow Survey. The study revealed that in 2011, energy consumption by motorized vehicles increased in the Traffic Assessment Zones of GTHA around the Growth Centres designated by the Places to Grow Plan. Active transportation increased mainly in Toronto in 2011. It is apprehended that the intensification strategy of the Places to Grow Plan contributed in increasing the energy consumption of work commuters either by increasing the number of trips or length of trips made by motorized vehicles (including cars and different forms of transit) which also affect the Greenhouse Gas emissions in the atmosphere.


2019 ◽  
Vol 10 (4) ◽  
pp. 627-647 ◽  
Author(s):  
Izabela Jonek-Kowalska

Research background: Energy policy is closely linked to economic development. Therefore, its optimization is an important issue especially in the contemporary European environmental conditions.  EU regulations enforce a reduction of carbon dioxide emissions and the abandonment of non-renewable energy resources. Instead, they promote renewable energy sources. In this way, new legal and environmental circumstances are becoming the main reason for the transformation of energy balances, which is a real economic and technological challenge. This transformation requires a strategic and effective approach, especially in those countries which until now have used mainly hard coal in the energy sector. Purpose of the article: According to above justification, the main purpose of the article is to identify the strategies for the transformation of energy balances that were implemented in the years 1990–2017 by chosen European countries and Turkey. Methods: The study period covers the years 1990–2017, and the subject of the research at first applies to all European countries, and then to 7 countries selected due to their high share of bituminous coal in energy balance in the first year of the analysis, treated as the initial point of transformation (1990). As a result of this selection, 6 EU members and Turkey with the largest share of coal in energy production in the year 1990 are examined. Particularly, an analysis of the trends in their energy balances in the years 1990–2017 is conducted. The research uses data on non-renewable energy consumption and renewable energy resources and the total energy consumption. The research methodology includes: analysis of the structure and dynamics, evaluation of trends and comparative analysis and presentation of development strategies. At the end of the article, a comparative analysis is carried out, the economic consequences of identified changes are assessed, and recommendations are formulated aimed at optimizing the structure of the energy balance in the future. Findings & Value added: Generally, there are four theoretical and empirical patterns of transformation strategies of energy balances with dominant coal consumption: 1) using other non-renewable energy resources; 2) replacing non-renewable energy resources with renewable ones; 3) using nuclear energy instead of coal; 4) increasing coal consumption as available and efficient energy resource. It was found that the examined countries implement mainly the strategy in which the decreasing share of coal is made up for by an increasing share of gas. Additionally, we can observe an increase in the share of nuclear energy in France, the Czech Republic and the United Kingdom. In Spain and Germany, despite the use of nuclear power plants for the production of energy, the share of nuclear energy in the energy balances has systematically decreased in time. In all analyzed countries, we can also observe an increasing share of renewable sources in energy balances, however, this growth is very slow.


2014 ◽  
Vol 881-883 ◽  
pp. 653-658 ◽  
Author(s):  
Yong Qiang Xiong ◽  
Ben Hua

In this paper, a cryogenic air separation process with LNG cold energy utilization is proposed to produce liquid nitrogen and high pressure pure oxygen gas economically. To reduce the electric energy consumption of air separation products, liquid nitrogen have been produced by condensing the separated pure nitrogen gas with LNG cold energy utilization, and the recycled nitrogen is served to transfer cold energy from LNG stream to cool off air stream in the proposed cryogenic air separation process. The specifications of streams and the major equipments of the air separation process are simulated with Aspen Plus software and the main parameters analysis are performed. The results show that the energy consumption of the proposed air separation process with LNG cold energy utilization decreased about 58.2% compared with a conventional cryogenic air separation process. The compressed pressure of recycled nitrogen has a big impact on the cost of air separation products and utilization efficiency of LNG cold energy. The LNG cold energy could be fully utilized when the recycled nitrogen has been compressed to above 6.5MPa.


Author(s):  
Janneth Ruiz ◽  
Antonio Ardila ◽  
Bernardo Rueda ◽  
Jorge Echeverri ◽  
Daniel Quintero ◽  
...  

Abstract In the ferronickel production process, mineral calcination is one of the most energy-intensive stages. In a typical rotary kiln calciner, particulate solids and combustions gases move counter currently, while solids undergo drying, pre-reduction, and partial reduction reactions. The combustion of natural gas provides the thermal energy for drying and reduction reactions. About 80 to 85% of the incoming laterite ore leaves the reactor as calcined ore, while the flue gases entrain part of the solids as dust. This work presents a theoretical analysis contrasted with experimental results to evaluate the partial reduction of laterite ores in two rotary kilns of 185 m and 135 m length. The study focused on the water formed in the process, including a comparative analysis of water consumption by two different solids recovery technologies, a gas scrubber and an electrostatic precipitator. Simulations allowed evaluating the water and greenhouse gas formation in the main streams of the process. Among the tested operation conditions, the moisture content in the pellets, consisting of agglomerated dust, strongly influenced the amount of water released in the process and the energy consumption. Furnace RK-2 needs approximately 56% more energy to evaporate the moisture content in the feedstock. Furthermore, furnace RK-2 released 55.4 m3h−1 of water into the atmosphere, which represented two times the amount released by furnace RK-1. Gas scrubber analysis showed that as the liquid water increased, more H2O in the gases was condensed; however, the destroyed exergy also increased. Electrostatic precipitators appear as an adequate technology for reducing water and energy consumption in the ferronickel industry.


2020 ◽  
Vol 2 (1) ◽  
Author(s):  
Suksun Amornraksa ◽  
Ittipat Subsaipin ◽  
Lida Simasatitkul ◽  
Suttichai Assabumrungrat

Abstract Separation process is very crucial in bioethanol production as it consumes the highest energy in the process. Unlike other works, this research systematically designed a suitable separation process for bioethanol production from corn stover by using thermodynamic insight. Two separation processes, i.e., extractive distillation (case 2) and pervaporation (case 3), were developed and compared with conventional molecular sieve (case 1). Process design and simulation were done by using Aspen Plus program. The process evaluation was done not only in terms of energy consumption and process economics but also in terms of environmental impacts. It was revealed that pervaporation is the best process in all aspects. Its energy consumption and carbon footprint are 60.8 and 68.34% lower than case 1, respectively. Its capital and production costs are also the lowest, 37.0 and 9.88% lower than case 1.


Sign in / Sign up

Export Citation Format

Share Document