scholarly journals Improvement of Energy Efficiency and Environmental Safety of Thermal Energy Through the Implementation of Contact Energy Exchange Processes

2017 ◽  
Vol 38 (4) ◽  
pp. 127-137
Author(s):  
Gennadii Borysovich Varlamov ◽  
Kateryna Alexandrovna Romanova ◽  
Iryna Nazarova ◽  
Olga Daschenko ◽  
Andry Kapustiansky
Keyword(s):  
Energy Efficiency ◽  
Flue Gas ◽  
Power Plants ◽  
Energy Exchange ◽  
Environmental Safety ◽  
Toxic Substances ◽  
Power Cycles ◽  
Energy Efficiency Improvement ◽  
Exchange Processes ◽  
Positive Effect

Abstract Energy efficiency improvement and ecological safety of heat power plants are urgent problems, which require scientifically grounded approaches and solutions. These problems can be solved partly within the presented heat-and-power cycles by including contact energy exchange equipment in the circuits of existing installations. A significant positive effect is obtained in the contact energy exchange installations, such as gas-steam installation ‘Aquarius’ and the contact hydrogen heat generator that also can use hydrogen as a fuel. In these plants, the efficiency increases approximately by 10-12% in comparison with traditional installations, and the concentration of toxic substances, such as nitrogen oxides and carbon monoxide in flue gas can be reduced to 30 mg/m3 and to 5 mg/m3, respectively. Moreover, the plants additionally ‘generate’ the clean water, which can be used for technical purposes.

NOx process inhibition and energy efficiency improvement in new swirl modification device for steel slag based on coal combustion

2018 ◽  
Vol 16 (7) ◽  
Author(s):  
Junxiang Guo ◽  
Lingling Zhang ◽  
Daqiang Cang ◽  
Liying Qi ◽  
Wenbin Dai ◽  
...  
Keyword(s):  
Energy Efficiency ◽  
Flue Gas ◽  
Coal Combustion ◽  
Steel Slag ◽  
Coal Ash ◽  
Combustion Efficiency ◽  
Gas Temperature ◽  
Staged Combustion ◽  
Energy Efficiency Improvement ◽  
Swirl Combustion

Abstract In this study, a novel swirl combustion modified device for steel slag was designed and enhanced with the objective of achieving highly efficient and clean coal combustion and also for achieving the whole elements utilization of coal. Coal ash and steel slag were melted in the combustion chamber and subsequently entered the slag chamber. The detrimental substances solidified and formed crystals, which allowed for the comprehensive utilization of the ash and slag. Our experiments mainly aimed to mitigate the formation of NOx, while using the heat and slag simultaneously during the coal combustion without a combustion efficiency penalty. The increase in the device’s energy efficiency and reduction in the NOx emissions are important requirements for industrialization. The experiments were carried out in an optimized swirling combustion device, which had a different structure and various coal feeding conditions in comparison to previously reported devices. The fuel-staged and non-staged combustion experiments were compared under different coal ratios (bitumite:anthracite). For the fuel-staged combustion experiments, the NOx concentration in the flue gas was observed to decrease significantly when the coal ratio of 1:1, an excess air coefficient of 1.2, and a fuel-staged ratio of 15:85 were used. Under these conditions, the flue gas temperature was as high as 1,620°C, while the NOx concentration was as low as 320 mg/m3 at 6 % O2. The air-surrounding-fuel structure that formed in the furnace was very beneficial in reducing the formation of NOx. In comparison to other types of coal burners, the experimental combustion device designed in this study achieved a significant reduction of NOx emissions (approximately 80 %).

scholarly journals Analysis of the evaporative towers cooling system of a coal-fired power plant

2012 ◽  
Vol 16 (suppl. 2) ◽  
pp. 375-385 ◽  
Author(s):  
Mirjana Lakovic ◽  
Slobodan Lakovic ◽  
Milos Banjac
Keyword(s):  
Energy Efficiency ◽  
Power Plant ◽  
Theoretical Analysis ◽  
Power Plants ◽  
Cooling Tower ◽  
Cooling System ◽  
Low Cost ◽  
Cooling Water ◽  
Energy Efficiency Improvement ◽  
Condensing Pressure

The paper presents a theoretical analysis of the cooling system of a 110 MW coal-fired power plant located in central Serbia, where eight evaporative towers cool down the plant. An updated research on the evaporative tower cooling system has been carried out to show the theoretical analysis of the tower heat and mass balance, taking into account the sensible and latent heat exchanged during the processes which occur inside these towers. Power plants which are using wet cooling towers for cooling condenser cooling water have higher design temperature of cooling water, thus the designed condensing pressure is higher compared to plants with a once-through cooling system. Daily and seasonal changes further deteriorate energy efficiency of these plants, so it can be concluded that these plants have up to 5% less efficiency compared to systems with once-through cooling. The whole analysis permitted to evaluate the optimal conditions, as far as the operation of the towers is concerned, and to suggest an improvement of the plant. Since plant energy efficiency improvement has become a quite common issue today, the evaluation of the cooling system operation was conducted under the hypothesis of an increase in the plant overall energy efficiency due to low cost improvement in cooling tower system.

scholarly journals The “rebound effect” of energy efficient actions to be performed as part of a major renovation of apartment buildings

2021 ◽  
pp. 44-48
Author(s):  
Valeriy Mishchenko ◽  
Elena Gorbaneva ◽  
Elena Ovchinnikova
Keyword(s):  
Energy Efficiency ◽  
Energy Efficient ◽  
Rebound Effect ◽  
Environmental Safety ◽  
Assessment Method ◽  
Energy Efficiency Improvement ◽  
Different Types ◽  
New Energy ◽  
Individual Household ◽  
The Impact

Environmental safety and the rational use of natural resources are among pressing present-day problems. Energy efficiency improvement is an important constituent of energy policies in many countries. This article examines the impact of the “rebound effect” on improving the energy efficiency of environmental safety programs implement-d at federal and municipal levels. There is still no consensus on how to take the “rebound effect” into account and whether it should be considered at all. Paradoxically, the “rebound effect” is the unintended side effect of energy efficiency activities. In this paper, different types of this effect are considered. The “direct assessment” method, based on the non-linear relationship between energy consumption and efficiency, is used to assess the “rebound effect” produced on individual household appliances. The factors hindering the implementation of energy efficiency activities are also identified. Having analyzed the impact of the effect on different sectors of economy, we can conclude that the most pronounced “rebound effect” is observed in the housing sector. Consequently, if we consider a major energy efficient renovation, we have to take account of the “rebound effect” caused by new energy saving activities.

scholarly journals A Study of Low-Potential Heat Utilization Methods for Oxy-Fuel Combustion Power Cycles

Energies ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3364
Author(s):  
Andrey Rogalev ◽  
Nikolay Rogalev ◽  
Vladimir Kindra ◽  
Olga Zlyvko ◽  
Andrey Vegera
Keyword(s):  
Co2 Emissions ◽  
Power Plants ◽  
Greenhouse Gas Emission ◽  
Thermal Power ◽  
Power Production ◽  
Environmental Safety ◽  
Plant Ecology ◽  
Fuel Combustion ◽  
Working Fluid ◽  
Power Cycles

The world community is worried about the effects of global warming. A few agreements on the reduction of CO2 emissions have been signed recently. A large part of these emissions is produced by the power production industry. Soon, the requirements for thermal power plant ecology and efficiency performance may become significantly higher. Thus, the contemporary problem is the development of highly efficient power production facilities with low toxic and greenhouse gas emission. An efficient way to reduce CO2 emissions into the atmosphere, which implies maintaining economic growth, is the creation of closed thermodynamic cycles with oxy-fuel combustion. The Allam cycle is one of the most promising among oxy-fuel power plants. A 50 MW pilot Allam cycle plant was built in Texas. The design for a commercial system with an electrical output of 300 MW is under development. This work is devoted to the improvement of the efficiency and environmental safety of oxy-fuel combustion power cycles via the utilization of compressed working fluid heat. The results of computer simulation obtained using AspenONE software demonstrated that an additional circuit in the multi-flow regenerator might increase net efficiency by 3.5%. Besides this, the incorporation of a supercritical carbon dioxide (S–CO2) Brayton cycle with recompression increased the efficiency by 0.2%. Therefore, the maximum net efficiency of the prospective power unit was 51.4%.

Could biomass-fueled boilers be operated at higher steam temperatures? Part 3: Initial analysis of costs and benefits

TAPPI Journal ◽  
2014 ◽  
Vol 13 (8) ◽  
pp. 65-78 ◽  
Author(s):  
W.B.A. (SANDY) SHARP ◽  
W.J. JIM FREDERICK ◽  
JAMES R. KEISER ◽  
DOUGLAS L. SINGBEIL
Keyword(s):  
Flue Gas ◽  
Power Plants ◽  
Superheated Steam ◽  
Black Liquor ◽  
Simulation Software ◽  
Operating Conditions ◽  
Costs And Benefits ◽  
Steam Generation ◽  
Fireside Corrosion ◽  
Corrosion Resistant

The efficiencies of biomass-fueled power plants are much lower than those of coal-fueled plants because they restrict their exit steam temperatures to inhibit fireside corrosion of superheater tubes. However, restricting the temperature of a given mass of steam produced by a biomass boiler decreases the amount of power that can be generated from this steam in the turbine generator. This paper examines the relationship between the temperature of superheated steam produced by a boiler and the quantity of power that it can generate. The thermodynamic basis for this relationship is presented, and the value of the additional power that could be generated by operating with higher superheated steam temperatures is estimated. Calculations are presented for five plants that produce both steam and power. Two are powered by black liquor recovery boilers and three by wood-fired boilers. Steam generation parameters for these plants were supplied by industrial partners. Calculations using thermodynamics-based plant simulation software show that the value of the increased power that could be generated in these units by increasing superheated steam temperatures 100°C above current operating conditions ranges between US$2,410,000 and US$11,180,000 per year. The costs and benefits of achieving higher superheated steam conditions in an individual boiler depend on local plant conditions and the price of power. However, the magnitude of the increased power that can be generated by increasing superheated steam temperatures is so great that it appears to justify the cost of corrosion-mitigation methods such as installing corrosion-resistant materials costing far more than current superheater alloys; redesigning biomassfueled boilers to remove the superheater from the flue gas path; or adding chemicals to remove corrosive constituents from the flue gas. The most economic pathways to higher steam temperatures will very likely involve combinations of these methods. Particularly attractive approaches include installing more corrosion-resistant alloys in the hottest superheater locations, and relocating the superheater from the flue gas path to an externally-fired location or to the loop seal of a circulating fluidized bed boiler.

Additional methods to improve the energy efficiency of oil pipeline transportation

2020 ◽  
Vol 10 (5) ◽  
pp. 558-565
Author(s):  
Marat R. Lukmanov ◽  
◽  
Sergey L. Semin ◽  
Pavel V. Fedorov ◽  
◽  
...  
Keyword(s):  
Energy Efficiency ◽  
Energy Saving ◽  
Pipeline System ◽  
Energy Costs ◽  
Improvement Program ◽  
Oil Pipeline ◽  
Energy Efficiency Improvement ◽  
Oil Transportation ◽  
Pumping Equipment ◽  
Preparatory Work

The challenges of increasing the energy efficiency of the economy as a whole and of certain production sectors in particular are a priority both in our country and abroad. As part of the energy policy of the Russian Federation to reduce the specific energy intensity of enterprises in the oil transportation system, Transneft PJSC developed and implements the energy saving and energy efficiency improvement Program. The application of energy-saving technologies allowed the company to significantly reduce operating costs and emissions of harmful substances. At the same time, further reduction of energy costs is complicated for objective reasons. The objective of this article is to present additional methods to improve the energy efficiency of oil transportation by the example of the organizational structure of Transneft. Possibilities to reduce energy costs in the organization of the operating services, planning and execution of work to eliminate defects and preparatory work for the scheduled shutdown of the pipeline, the use of pumping equipment, including pumps with variable speed drive, the use of various pipelines layouts, changing the volume of oil entering the pipeline system and increase its viscosity.

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