Analysis of the cumulative exergy consumption of an integrated oxy-fuel combustion power plant

Abstract In order to analyze the cumulative exergy consumption of an integrated oxy-fuel combustion power plant the method of balance equations was applied based on the principle that the cumulative exergy consumption charging the products of this process equals the sum of cumulative exergy consumption charging the substrates. The set of balance equations of the cumulative exergy consumption bases on the ‘input-output method’ of the direct energy consumption. In the structure of the balance we distinguished main products (e.g. electricity), by-products (e.g. nitrogen) and external supplies (fuels). In the balance model of cumulative exergy consumption it has been assumed that the cumulative exergy consumption charging the supplies from outside is a quantity known a priori resulting from the analysis of cumulative exergy consumption concerning the economy of the whole country. The byproducts are charged by the cumulative exergy consumption resulting from the principle of a replaced process. The cumulative exergy consumption of the main products is the final quantity.

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Analysis of cumulative energy consumption in an oxy-fuel combustion power plant integrated with a CO 2 processing unit

Energy Conversion and Management ◽

10.1016/j.enconman.2014.02.048 ◽

2014 ◽

Vol 87 ◽

pp. 1305-1314 ◽

Cited By ~ 12

Author(s):

Andrzej Ziębik ◽

Paweł Gładysz

Keyword(s):

Energy Consumption ◽

Power Plant ◽

Fuel Combustion ◽

Processing Unit ◽

Cumulative Energy

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System approach to the analysis of an integrated oxy-fuel combustion power plant

Archives of Thermodynamics ◽

10.2478/aoter-2014-0020 ◽

2014 ◽

Vol 35 (3) ◽

pp. 39-57 ◽

Cited By ~ 5

Author(s):

Andrzej Ziębik ◽

Paweł Gładysz

Keyword(s):

Power Plant ◽

System Approach ◽

System Analysis ◽

Flame Temperature ◽

Combustion Process ◽

Fuel Combustion ◽

Air Separation ◽

Processing Unit ◽

Separation Unit ◽

Direct Energy

Abstract Oxy-fuel combustion (OFC) belongs to one of the three commonly known clean coal technologies for power generation sector and other industry sectors responsible for CO2 emissions (e.g., steel or cement production). The OFC capture technology is based on using high-purity oxygen in the combustion process instead of atmospheric air. Therefore flue gases have a high concentration of CO2. Due to the limited adiabatic temperature of combustion some part of CO2 must be recycled to the boiler in order to maintain a proper flame temperature. An integrated oxy-fuel combustion power plant constitutes a system consisting of the following technological modules: boiler, steam cycle, air separation unit, cooling water and water treatment system, flue gas quality control system and CO2 processing unit. Due to the interconnections between technological modules, energy, exergy and ecological analyses require a system approach. The paper present the system approach based on the ‘input-output’ method to the analysis of the: direct energy and material consumption, cumulative energy and exergy consumption, system (local and cumulative) exergy losses, and thermoecological cost. Other measures like cumulative degree of perfection or index of sustainable development are also proposed. The paper presents a complex example of the system analysis (from direct energy consumption to thermoecological cost) of an advanced integrated OFC power plant.

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Process Simulation of Oxy-Fuel Combustion for A 120 MW Coal-Fired Power Plant Using Aspen Plus

International Journal of Natural Sciences Research ◽

10.18488/journal.63.2021.91.26.38 ◽

2021 ◽

Vol 9 (1) ◽

pp. 26-38

Author(s):

Odeh A.O ◽

Okpaire L.A ◽

Oyedoh E.A

Keyword(s):

Power Plant ◽

Flue Gas ◽

Process Simulation ◽

Flame Temperature ◽

Aspen Plus ◽

Fuel Combustion ◽

Nox Emissions ◽

Input Output ◽

Boiler Efficiency ◽

Direct Input

Oxy-fuel Combustion is a technology with the potential of drastically reducing the amount of CO2 emission, it relies on the use of oxygen and recycled CO2 instead of air as the oxidant. This helps to reduce the amount of the CO2 and NOx emissions. This study focuses on the components of flue gas produced and their amounts for oxy-fuel combustion in a coal-fired power plant (CFPP) and also the boiler efficiency using the direct (input-output) method. The combustion process of pulverized coal in a 120MW power plant is studied using Aspen Plus 11. The amount of each component in flue gas in coal-fired processes with air or O2/ CO2 (using recycle of 20%, 40%, 60% and 80% of CO2) as oxidizer was obtained. From the process simulation, as the recycle % of CO2 was increased, the flame temperature, CO and NOx emissions were reduced. The simulation results of air combustion were compared with that of oxy-fuel combustion with 80% recycle and it was seen that the flame temperature dropped from 1894oC when air was used as oxidizer to 1679oC for oxy-fuel combustion with 80% recycle. Also, there was a reduction in the amount of NOx produced, but the SOx levels were constant for both combustion processes. The Gross Calorific Value (GCV) of the coal was calculated from its Proximate Analysis using Dulong’s formula and it was used to estimate the Boiler Efficiency using the Direct (Input-Output) method and a value of 83.6% was obtained.

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Saving Primary Energy Consumption Through Exergy Analysis of Combine Distillation and Power Plant

Scientific Research Journal ◽

10.24191/srj.v9i2.5388 ◽

2012 ◽

Vol 9 (2) ◽

pp. 65

Author(s):

Alhassan Salami Tijani ◽

Nazri Mohammed ◽

Werner Witt

Keyword(s):

Energy Consumption ◽

Power Plant ◽

Heat Pump ◽

Heat Recovery ◽

Energy Savings ◽

Primary Energy ◽

Heat Pumps ◽

Saturated Steam ◽

Distillation Unit ◽

Primary Energy Consumption

Industrial heat pumps are heat-recovery systems that allow the temperature ofwaste-heat stream to be increased to a higher, more efficient temperature. Consequently, heat pumps can improve energy efficiency in industrial processes as well as energy savings when conventional passive-heat recovery is not possible. In this paper, possible ways of saving energy in the chemical industry are considered, the objective is to reduce the primary energy (such as coal) consumption of power plant. Particularly the thermodynamic analyses ofintegrating backpressure turbine ofa power plant with distillation units have been considered. Some practical examples such as conventional distillation unit and heat pump are used as a means of reducing primary energy consumption with tangible indications of energy savings. The heat pump distillation is operated via electrical power from the power plant. The exergy efficiency ofthe primary fuel is calculated for different operating range ofthe heat pump distillation. This is then compared with a conventional distillation unit that depends on saturated steam from a power plant as the source of energy. The results obtained show that heat pump distillation is an economic way to save energy if the temperaturedifference between the overhead and the bottom is small. Based on the result, the energy saved by the application of a heat pump distillation is improved compared to conventional distillation unit.

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Changes in Power Plant NOx Emissions over Northwest Greece Using a Data Assimilation Technique

Atmosphere ◽

10.3390/atmos12070900 ◽

2021 ◽

Vol 12 (7) ◽

pp. 900

Author(s):

Ioanna Skoulidou ◽

Maria-Elissavet Koukouli ◽

Arjo Segers ◽

Astrid Manders ◽

Dimitris Balis ◽

...

Keyword(s):

Power Plant ◽

Data Assimilation ◽

Energy Production ◽

Power Plants ◽

Transport Model ◽

A Priori ◽

Filter Method ◽

Nox Emissions ◽

A Posteriori ◽

Data Assimilation Technique

In this work, we investigate the ability of a data assimilation technique and space-borne observations to quantify and monitor changes in nitrogen oxides (NOx) emissions over Northwestern Greece for the summers of 2018 and 2019. In this region, four lignite-burning power plants are located. The data assimilation technique, based on the Ensemble Kalman Filter method, is employed to combine space-borne atmospheric observations from the high spatial resolution Sentinel-5 Precursor (S5P) Tropospheric Monitoring Instrument (TROPOMI) and simulations using the LOTOS-EUROS Chemical Transport model. The Copernicus Atmosphere Monitoring Service-Regional European emissions (CAMS-REG, version 4.2) inventory based on the year 2015 is used as the a priori emissions in the simulations. Surface measurements of nitrogen dioxide (NO2) from air quality stations operating in the region are compared with the model surface NO2 output using either the a priori (base run) or the a posteriori (assimilated run) NOx emissions. Relative to the a priori emissions, the assimilation suggests a strong decrease in concentrations for the station located near the largest power plant, by 80% in 2019 and by 67% in 2018. Concerning the estimated annual a posteriori NOx emissions, it was found that, for the pixels hosting the two largest power plants, the assimilated run results in emissions decreased by ~40–50% for 2018 compared to 2015, whereas a larger decrease, of ~70% for both power plants, was found for 2019, after assimilating the space-born observations. For the same power plants, the European Pollutant Release and Transfer Register (E-PRTR) reports decreased emissions in 2018 and 2019 compared to 2015 (−35% and −38% in 2018, −62% and −72% in 2019), in good agreement with the estimated emissions. We further compare the a posteriori emissions to the reported energy production of the power plants during the summer of 2018 and 2019. Mean decreases of about −35% and−63% in NOx emissions are estimated for the two larger power plants in summer of 2018 and 2019, respectively, which are supported by similar decreases in the reported energy production of the power plants (~−30% and −70%, respectively).

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