Flue Gas Volume Research Articles

Combustion and Energy Parameters of Grape Pomace/Skin Waste in Wine Production—Regent Variety Grafted onto Rootstocks

The study presents the potential use of winemaking residues, specifically grape pomace, for energy purposes. The pomace was obtained from the cultivation of the Regent grape variety on three different rootstocks—125AA, 161-49, and SO4—as well as a control group grown on its own roots. The research included determining the calorific value and combustion heat, conducting a technical and elemental analysis of the potential biofuel, as well as estimating emission indicators (CO, CO2, NOx, SO2, and particulate matter) and the theoretical volume of flue gases based on stoichiometric equations. The study revealed significant differences among the combustion heat, tested properties and calorific value, ash content, and the total volume of flue gases. The highest calorific value (17.7 MJ kg−1) and combustion heat (18.9 MJ kg−1) were obtained for pomace from the SO4SO4 rootstock, while the lowest values were observed in the control group (17.0 MJ·kg−1 and 15.8 MJ·kg−1, respectively). The highest ash content was also recorded for the SO4 rootstock (9.2%), with the lowest in the control group (6.7%). The control group exhibited the lowest CO2 emissions at 1390.50 kg·Mg−1, while the highest emissions were found in the pomace from the SO4 rootstock (1478.8 kg·Mg−1). Regarding the total flue gas volume, the highest volume was estimated for the pomace from the 125AA rootstock (7.8 m3·kg−1) and the lowest for the control group (7.3 m3·kg−1). The research demonstrated that grape pomace possesses favorable energy properties and could serve as a potential biofuel, contributing to the fuel and energy balance of agricultural production enterprises. The analyzed biomass exhibits properties similar to agrobiomass.

Analysis of the Energy–Carbon Potential of the Pericarp Cover of Selected Hazelnut Varieties

The research presents weight estimation and analysis of the energy and carbon potential of the pericarp cover of four hazelnut varieties. A technical and elementary biofuel analysis was carried out for the biomass studied, as well as a correlation and principal component analysis to demonstrate the influence of individual characteristics on the parameters achieved. In addition, emission factors and the composition and volume of flue gases from the combustion of the material studied were estimated based on stoichiometric equations. The research showed that the highest calorific value (LHV) was characterised by the pericarp cover of the ‘Olga’ variety (14.86 MJ·kg−1) and the lowest by the ‘Kataloński’ variety (14.60 MJ·kg−1). In the case of exhaust volume, the highest volume was obtained from the ‘Olbrzymi z Halle’ variety (250.06 Nm3·kg−1) and the lowest from the ‘Kataloński’ variety (12.43 Nm3·kg−1). The correlation analysis carried out showed that the HHV and LHV parameters in the covers showed a very strong positive correlation with sulphur content and SO2 emissions, and a moderate correlation with nitrogen content and its associated NOx emissions, indicating their direct influence on the higher calorific value of biomass.

Proposal and thermodynamic investigation of pressurized calcium looping integrated with chemical looping combustion for tail-end CO2 capture in a retrofitted natural gas combined cycle power plant

The integration of tail-end calcium looping into an existing natural gas combined cycle (NGCC) power plant has minimal impact on CO2 capture retrofits. However, a high volume of flue gas needs to be preheated before entering the carbonator, and the relatively high energy consumption of oxygen production exacerbates the energy penalty of the NGCC system with tail-end CO2 capture. This paper proposes the method of pressurized calcium looping integrated with chemical looping combustion (PCaL-CLC). It employs the PCaL-CLC method to reduce the energy penalty and energy consumption of the NGCC system with tail-end CO2 capture. Results show that the proposed system using the PCaL-CLC method achieves a 3.0% reduction in energy penalty, decreasing from 9.1% in the reference system employing the calcium looping method to 6.1% in the proposed system. Besides, the specific energy consumption for CO2 avoided (SPECCA) declines from 4.43 MJLHV/kg CO2 to 2.76 MJLHV/kg CO2. Exergy analysis and energy utilization diagrams reveal the underlying reason for improving system performance. Furthermore, by optimizing the operating parameters of the gas turbine and equipping it with advanced heat recovery steam generation, an energy penalty of 2.9% and a SPECCA of 1.21 MJLHV/kg CO2 are achieved without CO2 compression, which is superior to those of amine scrubbing and hot-end calcium looping CO2 capture technologies. The proposed PCaL-CLC method offers an alternative approach to reducing the energy consumption of tail-end CO2 capture in existing natural gas combined cycle power plants.

Method of controlling the volume of combustion products at different boiler loads

Purpose. Development of a method for controlling the volume of combustion products at different load of boiler equipment. Achieving the objective may allow controlling the flue gas temperature and, consequently, the efficiency to increase it. Methodology. Control of the flue gas volume value on the basis of determining the appropriate composition of the fuel gas mixture. Findings. The effect of flue gas temperature increase at use of fuel gases of lower calorific value and increase in ballast gases quantity is revealed. The latter can be the air used as an oxidising agent at its considerable excess. The mechanism of such an effect due to the increase in the quantity and velocity of flue gases is suggested. A parameter determining the volume of flue gases produced per unit calorific value of various fuel gases is proposed. On the basis of this parameter the method for calculating the composition of the mixture of different gases to ensure the constancy of the flue gas volume at variable load is proposed Originality. On the example of the results of verification thermal calculation the change in flue gas temperature and efficiency value is considered. The non-standard character of their change is revealed. In contrast to the case of using fuel gas of constant composition with increasing load, the temperature of flue gases remained close to constant, and the value of efficiency increased. Practical value. The obtained results indicate the possibility of controlling the flue gas temperature and boiler efficiency at a given load. This allows one, unlike the case of using fuel gas of constant composition, to increase the efficiency exactly at maximum load avoiding getting into the condensate mode at minimum load. There is a possibility to save fossil gas and, consequently, to reduce the greenhouse share in CO2 emissions.

IMPROVED LEVEL OF TECHNOGENIC SAFETY IN PLANTS INTENDED MUNICIPAL SOLID WASTE INCINERATION

Solid municipal waste can be an alternative and renewable type of fuel. Waste incineration provides effective disposal, significant volume reduction and utilization of the energy potential of the carbon waste part. In order to protect the components of the biosphere and service personnel from harmful substances that are formed in the furnace space, it is first necessary to assess the chemical composition and volume of emissions. The purpose of the work is to study the process of burning municipal waste, determine the heat energy obtained, determine the amount of air required for the complete combustion reaction, and determine the volume of flue gases produced as a result of combustion. To achieve the goal of the research, a complex of methods of system analysis and the method of data analysis was applied. An analysis of modern international literary sources, an analysis of the morphological composition of the combustible part of solid household waste, and an analysis of the interaction of chemical substances was carried out. For the research, several components of waste were collected, which were conditionally divided into two main groups - paper and plastic. The first group includes waste, which includes wood, cardboard, and paper. The second group (plastic) includes waste, which includes plastic in the form of scraps of polyethylene film, disposable dishes. As a result of the research, a theoretical volume of combustion products was obtained for the further design of the system of protection of the environment and service personnel from emissions of thermal disposal of solid household waste. Research results can be used in the design of municipal waste incineration equipment. The system of using the heat of flue gases generated after burning waste to dry the waste before feeding it to the furnace is of great importance for saving additional fuel.

Limestone hydrogenation combined with reverse water–gas shift reaction under fluidized and iso-thermal conditions using MFB-TGA-MS

The integrated CO2 capture and utilization (ICCU) in conjunction with the reverse water–gas shift (RWGS) reaction has emerged as a promising approach to achieve carbon neutrality. However, the scalability of CaCO3 hydrogenation in the context of large volumes of industrial flue gas is impeded by the limited understanding of its performance under fluidized and iso-thermal conditions. This study utilized micro-fluidized bed thermogravimetric analysis coupled with mass spectrometry (MFB-TGA-MS) and in-situ measurements to investigate limestone decomposition under H2 and Ar atmospheres. Results showed that H2 atmosphere increased the limestone decomposition rate by 5-fold (79.1% CO2 conversion and ∼100% CO selectivity at 710 °C) compared to Ar, with RWGS as the dominant route and self-catalytic activity of calcined CaO. Morphology evolution revealed finer pores and textures under H2 conditions. Meanwhile, apparent kinetic models analyzed experimental data and showed a reduction in activation energy from 178.5 kJ/mol (Ar) to 161.3 kJ/mol (H2). These findings support the effectiveness of ICCU-RWGS approaches for further commercialization.

Identification of combustion regularities of fuel mixtures from Azolla biomass, goat manure biochar and goat manure bio-oil for FCC furnace

Fluid catalytic cracking (FCC) is a method of cracking vegetable oils into simpler fractions and green fuel oils. One component of the FCC system is the FCC furnace. The FCC furnace is where the combustion process occurs and provides high heat transfer throughout the FCC system, especially for heating the reactor. The reactor temperature is the catalyst cracking temperature. The cracking temperature of the catalyst depends on the feed oil used in the cracking process, such as crude palm oil at 450‒550 °C or crude bio-oil at 300 °C. The fuel for heating an FCC furnace is usually coal. To reduce coal, we use a mixture of Azolla microphylla biomass with biochar and bio-oil from goat manure. The aim of this study was to analyze the mixture of Azolla microphylla biomass with biochar and bio-oil from goat manure to obtain sufficient furnace temperature to heat the FCC reactor, perform analytical calculations to obtain the volume of flue gas formed from the combustion reaction. We conducted two experiments; the first experiment used a mixture of 1 kg of Goat Manure Biochar (GMBC) with 0.5 kg of Azolla microphylla and the second experiment used a mixture of one kg of GMBC with 0.5 kg of Azolla microphylla plus 300 ml of Goat Manure Bio-oil (GMBO). A fuel mixture of one kilogram GMBC with 0.5 kg Azolla is not effective in combustion because the maximum temperature in the furnace is 177 °C but the fuel mixture of one kg GMBC, 0.5 kg Azolla and 300 ml GMBO has a furnace temperature of 472.75 °C, which can heat the stripper up to 313.25 °C so that cracking can occur in the raw bio-oil. Analysis of combustion results showed an increase in total CO2 volume from experiment one and experiment two of 0.966

Techno-Economic Analysis of Carbon Dioxide Separation for an Innovative Energy Concept towards Low-Emission Glass Melting

The currently still high fossil energy demand is forcing the glass industry to search for innovative approaches for the reduction in CO2 emissions and the integration of renewable energy sources. In this paper, a novel power-to-methane concept is presented and discussed for this purpose. A special focus is on methods for the required CO2 capture from typical flue gases in the glass industry, which have hardly been explored to date. To close this research gap, process simulation models are developed to investigate post-combustion CO2 capture by absorption processes, followed by a techno-economic evaluation. Due to reduced flue gas volume, the designed CO2 capture plant is found to be much smaller (40 m3 absorber column volume) than absorption-based CO2 separation processes for power plants (12,560 m3 absorber column volume). As there are many options for waste heat utilization in the glass industry, the waste heat required for CO2 desorption can be generated in a particularly efficient and cost-effective way. The resulting CO2 separation costs range between 41 and 42 EUR/t CO2, depending on waste heat utilization for desorption. These costs are below the values of 50–65 EUR/t CO2 for comparable industrial applications. Despite these promising economic results, there are still some technical restrictions in terms of solvent degradation due to the high oxygen content in flue gas compositions. The results of this study point towards parametric studies for approaching these issues, such as the use of secondary and tertiary amines as solvents, or the optimization of operating conditions such as stripper pressure for further cost reductions potential.

Desulfurization in co-firing of sewage sludge and wooden biomass in a bubbling fluidized bed combustor under air and oxy-fuel conditions

This work presents results of an experimental investigation of a direct addition of Ca-based sorbent for SO2 capture in a bubbling fluidized bed combustion. The fuel of interest was secondary biomass represented by a dried sewage sludge, which was mixed with primary biomass represented by wooden pellets in a weight ratio of 30:70. The performance of this SO2 capture approach is compared in air and oxy-fuel combustion conditions, since the different gas environment in the bed significantly affects the SO2 capture process. The experiments were carried out in an experimental bubbling fluidized bed combustor with a power load of about 30 kW.Sewage sludge is typical for its high ash content and has sufficient dimensions and attrition resistance to create the fluidized bed without the support of external bed materials. However, it typically consists of S-containing organic substances, resulting in the presence of SOX in the off-gas. A reference case was initially conducted without any sorbent addition in order to investigate the effect of sulfur self-retention in the fuel ash. The sulfur retention in the ash reached almost 45 % in air- and up to 55 % under oxy-combustion.In the next phase, the performance of Ca-based sorbents in sulfur capture was evaluated. The sorbents were represented by two types of limestone with diverse CaCO3 content produced at different locations. The experiments were carried out with three Ca/S mole ratios (1.5, 3, and 4.5). The effect of the fluidized bed temperature was also investigated as the most important parameter.The SO2 capture ratio (used as a performance indicator) was calculated based on emission factors, due to the different specific volumes of flue gas in the air and oxy-fuel modes. The results show in general a significantly higher SO2 capture ratio under oxy-fuel conditions. The differences are more significant in lower Ca/S ratios, where the SO2 capture ratio increased from 46 % under air conditions to 75 % under oxy-fuel for Ca/S = 1.5. In the case of the highest Ca/S ratio examined (Ca/S = 4.5), the increase in SO2 capture was from 90 % to 95 %.

Process design and optimization on self-sustaining pyrolysis and carbonization of municipal sewage sludge

Pyrolysis can realize the reduction and resource utilization of municipal sewage sludge (MSS). In this paper, a self-sustaining pyrolysis process is designed for municipal sewage sludge, and the process flow is simulated by Aspen plus software. By changing the initial moisture content of sludge, moisture content after drying, pyrolysis temperature and air supply in the incinerator, the possibility of achieving energy self-balance in the system is analysed. The simulation results show that by adjusting the parameters of the system, this process can realize the energy self-balance of sludge drying and pyrolysis treatment. Considering the system’s energy loss, the dry basis calorific value of sludge should not be less than 10 MJ/kg. The higher the initial moisture content of sludge, the more external energy input the system needs. It is recommended to dehydrate sludge mechanically to about 60 % before entering the system. When the pyrolysis temperature is increased, the amount of oil and gas produced by sludge pyrolysis increases, and it is easier to achieve self-balance of system energy. But the higher the pyrolysis temperature, the greater the energy consumption required. In practice, it is suggested that the pyrolysis temperature is about 400 °C. The moisture content of dried sludge has little effect on the energy self-balance of the system, and it is recommended to be about 30 %. The air supply volume of the incinerator mainly affects the flue gas outlet temperature and flue gas volume, but has little effect on the energy balance of the system.

EXPERIMENTAL INVESTIGATION OF OXYFUEL COMBUSTION OF RDF AND WOOD CHIPS IN A GRATE INCINERATION SYSTEM

Combustion experiments of dried wood chips and refuse derived fuel (RDF) under air and oxyfuel conditions have been performed in an extendedly modified 240 kW<sub>Th</sub> pilot-scale grate incineration facility with forward acting grate. To get insight into differences of the combustion processes between air and oxyfuel operation the concentrations of the main flue-gas species have been measured at the end of the combustion chamber and throughout the furnace. Additionally, the temperature has been measured inside the grate bars and the fuel bed as well as along the flue-gas pathway. It could be demonstrated that oxyfuel combustion of wood chips leads to stable CO<sub>2</sub> concentrations in the dry flue gas above 80 vol. %. During oxyfuel combustion of RDF similar trends have been observed; however, the combustion has shown significant fluctuations due to fuel-feeding issues. Profile measurements revealed a spatially extended reaction zone in the oxyfuel cases compared to the respective air combustion cases but with decreasing differences towards the end of the combustion zone. Wet flue-gas recycling has been applied to the experimental system which led to significantly higher H<sub>2</sub>O concentrations in the furnace during oxyfuel operation. Concentrations of CO, NO, SO<sub>2</sub>, and HCl in the flue gas have been increased during oxyfuel combustion. Especially during RDF oxyfuel combustion the concentration of HCl and SO<sub>2</sub> in the flue gas has been very high. In such a case it would be necessary to recycle the flue gas after appropriate cleaning steps. Also, considering the significantly lower flue-gas volume flow towards the atmosphere absolute emissions seem to be manageable.

THE INFLUENCE OF HYDROGEN CONCENTRATION IN NATURAL GAS ON HEAT FLOWS IN A THERMAL AGGREGATE

Natural gas is currently a hotly debated topic both from an environmental point of view due to the production of CO2 and from an economic point of view. The article is focused on the analysis of selected energy factors when burning natural gas with a gradual increase in the hydrogen content in the fuel mixture. In the article, the authors focused on modelling combustion and the influence of hydrogen concentration on heat flows from flue gas in a thermal aggregate. The aim of the authors is to point out changes combustion in the thermal aggregate using document analysis and calculations. By gradually increasing hydrogen in natural gas, it is possible to prove the effect on heat flows during the exchange of heat from the flue gas to the heated material. According to the results, it can be concluded that increasing the content of methane in natural gas changes the nature of the combustion of the mixture. The combustion temperature increases, heat flow density, on the other hand, the volume of flue gas converted to 1 m3 of fuel decreases. An important factor that positively decreases in this is the CO2 emission factor.

Theoretical Air Requirement and Combustion Flue Gases Analysis for Indigenous Biomass Combustion

Rice-husk is one of the most abundant and commonly utilized biomass. It can be used directly to generate primary heating agent in combustion plants. However, emission characteristic of biomass usually vary depending on factors such as the variety of the parent plant, region of cultivation and climatic condition. Moreover, gases emission from biomass combustion could be detrimental to health; hence there is a need for information on the theoretical volume of air and flue gases required for optimal operation of combustion equipment. Thus, this work analyzed the theoretical combustion air requirement and the resulting flue gas volume of the abundant Nerica-rice-husk variety. Rice-husk samples were collected from southwestern part of Nigeria. The samples were characterised for their ultimate and proximate content. Afterward, the combustion analysis was carried out using the elemental composition obtained from the ultimate analysis to determine the theoretical combustion air requirement and the resulting flue gas volume. The proximate analysis result showed the moisture content level, fixed carbon content and ash content value of 10.93%,12.59% and 18.26% respectively for sample A and 9.80%, 20.76% and 14.81% for sample B. This reveals that Nerica-rice-husk is advisable for use as an alternative energy source in a combustion process. The calculated theoretical volume of air for sample A was 3.69596 (N m3/kg fuel), while 3.53947 (N m3/kg fuel) was obtained for sample B. This signifies a slight different between the combustion properties of rice-husk of same variety. It also showed that more quantity of theoretical air will be required to burn sample A compared to sample B, and that sample A will generate little more emissions compared to sample B. Hence, this study reveals the volume of air required for low emission combustion of Nerica-rice-husk in combustion plants.

Flue Gas Composition and Treatment Potential of a Waste Incineration Plant

Waste-to-energy (WtE) incineration is an important technique in waste management systems and waste hierarchy. It is used to treat approximately 63% of the waste in European countries. The flue gas volumetric rate and its composition are essential to determine and monitor the emissions from waste incineration plants. This paper presents two methodologies used to evaluate the emissions from incinerators during the design phase. The first consists of a set of equations applicable in Excel (calculation model), while the second is the built-in components in Ebsilon 13.2 software which simulates the emissions from a furnace. This paper also proposes a comprehensive flue gas cleaning system for a simulated waste incineration plant in Jordan. According to Ebsilon, the results showed that for a 25 kg/s loading rate, there was 258,514 mg/Nm3, 749.90 mg/Nm3, 890.20 mg/Nm3, and 717 mg/Nm3 of CO2, NO2, SO2, and HCL, respectively. It was noted that these values relate to 1.5 of excess air ratio, where the effect of excess air ratio as the main driver for any combustion process was examined. The calculation method (set of equations) evaluated the flue gas volumetric rate, the CO2 emissions, and N2O and SO2 levels. Ebsilon allows for simulation of the treatment stages and calculates the amount of materials required. Selective non-catalytic reduction (SNCR) (a built-in component in the Ebsilon library) was used to treat the NO2 emissions. For 1.5 of excess air ratio, those emissions were reduced from 749 mg/Nm3 to 180 mg/Nm3, while the Ca(OH)2 injector used to treat the SO2 and HCL emissions reduced emissions from 890.20 mg/Nm3 and 717 mg/Nm3 to 44 mg/Nm3 and 7.16 mg/Nm3, respectively. Regarding the reduction in CO2, the spherical carbon absorption concept was simulated using 9.4 kg/s of carbon which was adequate to verify a 91% reduction rate of CO2. Furthermore, the calculation model was validated and approved as a valuable model to predict the flue gas volume, the oxygen required, and flue gas emissions at the design stage.

Daily Emission Patterns of Coal-Fired Power Plants in China Based on Multisource Data Fusion.

Daily emission estimates are essential for tracking the dynamic changes in emission sources. In this work, we estimate daily emissions of coal-fired power plants in China during 2017-2020 by combining information from the unit-based China coal-fired Power plant Emissions Database (CPED) and real-time measurements from continuous emission monitoring systems (CEMS). We develop a step-by-step method to screen outliers and impute missing values for data from CEMS. Then, plant-level daily profiles of flue gas volume and emissions obtained from CEMS are coupled with annual emissions from CPED to derive daily emissions. Reasonable agreement is found between emission variations and available statistics (i.e., monthly power generation and daily coal consumption). Daily power emissions are in the range of 6267-12,994, 0.4-1.3, 6.5-12.0, and 2.5-6.8 Gg for CO2, PM2.5, NO x , and SO2, respectively, with high emissions in winter and summer caused by heating and cooling demand. Our estimates can capture sudden decreases (e.g., those associated with COVID-19 lockdowns and short-term emission controls) or increases (e.g., those related to a drought) in daily power emissions during typical socioeconomic events. We also find that weekly patterns from CEMS exhibit no obvious weekend effect compared to those in previous studies. The daily power emissions will help to improve chemical transport modeling and facilitate policy formulation.

Using Wood-Based Waste from Grapevine Cultivation for Energy Purposes

This paper presents the possibility of the energetic utilization of biowaste in the form of lignified one-year shoots from the cultivation of grapevines of the Seyval Blanc (WSBL), Solaris (WSOL), Regent (WREG) and Rondo (WRON) varieties, grown in temperate climate zones. A technical analysis, an elemental analysis and the determination of the highest heat value and lowest heat value were performed to define the quality parameters of waste as fuel. In addition, the emission factors of SO2, NOx, CO, CO2 and dust were estimated to demonstrate the impact of potential biowaste from combustion. Based on the stoichiometric equations, the exhaust gas composition, the theoretical oxygen demand and the total flue gas volume were evaluated. The study showed that the material with the highest energy potential was WREG (LHV-16.19 MJ·kg−1), with an ash content of 3.68%, while the lowest potential was found for WRON (LHV-15.88 MJ·kg−1), with an ash content of 4.21%. The study showed that the use of the studied viticulture waste instead of hard coal could reduce CO emissions by 26–27%, CO2 by 24–26%, NOx by 55–56%, SO2 by 96–97% and dust by 77–80%.

Modelling and simulation of the volume flow of NH3, K2CO3 and MEA for the Carbon dioxide absorption from coal

Computational models have been developed and solved by the use of a computer coded software Python on Spyder console. The models were developed to gain an improved insight of carbon dioxide capture process performance by concentrating on the volume flowrate of the flue gas. The models were based on chemical absorption method. The study was aimed at exploring the absorption capacity of monoethanolamine (MEA), chilled ammonia and potassium carbonate (K2CO3) systems by concentrating on the movement of flue gas volume. The profiling of volume was prepared in order to see how much of the flue gas will be lost at the end of absorption when the three mentioned absorbent are used to capture carbon dioxide (CO2). The results showed that high volume flow of the gaseous phase has led to poor absorption, whilst low volume flow yields higher CO2 absorption. Moreover, in comparison to K2CO3 and chilled ammonia, the MEA was found to have the best absorption capacity.

Experimental research and engineering application on the treatment of desulfurization wastewater from coal-fired power plants by spray evaporation

The spray evaporation is a promising zero discharge technology for desulphurization wastewater treatment. In this work, a pilot-scale platform for the spray evaporation of desulfurization wastewater was built, the desulphurization wastewater was atomized by a rotary atomizer and evaporate in the evaporation tower, and the wastewater atomization and evaporation characteristics were investigated systematically. The results showed that the increase of atomizer rotating speed can improve the atomization effect of desulfurization wastewater, while the increase of its flow rate and total amount of dissolved solids (TDS) was not conducive to that. For the evaporation of desulfurization wastewater, the increase of flue gas temperature, gas-liquid ratio (the ratio of flue gas volume to desulfurization wastewater volume, Nm3 m−3) and atomizer rotating speed can promote its rapid evaporation, while the increase of wastewater TDS reduced the evaporation rate of wastewater droplets. On this basis, a bypass evaporation tower system was designed and constructed in a 330 MW coal-fired power plant to treat the desulphurization wastewater from limestone–gypsum wet flue gas desulfurization (WFGD) system, and the influence of wastewater evaporation on the flue gas and particle characteristics was investigated under different boiler loads. The results show that this evaporation system can ensure the evaporation effect of desulphurization wastewater under different boiler loads, lead to the reduction of flue gas temperature and the increase of humidity, reduce the concentration of SO2 and particles in flue gas, and enlarge the particle size at the outlet of evaporation tower. This work can provide a reference for the desulphurization wastewater treatment in coal-fired power plants.

A new method for calculating the theoretical dry flue gas volume of metallurgical gas

Aimed at the limited engineering condition that only gas calorific value but not gas composition can be provided, a new theoretical combustion calculation method based on gas calorific value was proposed, which is suitable for calculating the theoretical dry flue gas volume of metallurgical gas. In the new method, three simplified models were proposed, including blast furnace gas (BFG) model, Linz–Donawitz converter gas (LDG) model and coke oven gas (COG) model. The simplified models were respectively derived from the original model of theoretical combustion calculation, according to the composition characteristics of each metallurgical gas. Finally, the proposed models were verified through large sample of BFG, LDG and COG. The verification results show that the new models for calculating the theoretical dry flue gas volume of metallurgical gas all have high accuracy. The average relative errors of BFG model, LDG model and COG model are only 0.35%, 0.12%, 0.64% respectively. Thus, the new method proposed in this paper is reasonable and feasible. It can meet the accuracy requirement of engineering and can provide a new way for theoretical combustion calculation of metallurgical gas.

Calculation of standards for permissible environmental impact for boilers with known technical characteristics

Emission of thermal power stations and boilers is regulated in accordance with the unified national regulatory requirements, taking into account the specifics of energy production, its life-sustaining function and is aimed at ensuring that air pollution is prevented as much as possible. The purpose of the regulation of emissions of thermal power plants is to limit its adverse impact on the air basin by developing, for the entire thermal power plant and each source of emissions on it, the maximum allowable emissions – control (in grams per second) and per annum (in tons per year), ensuring sanitary hygienic standards. Sanitary standards include the maximum permissible concentration, which reflects the level of components in the air that is safe for humans. In practice, several substances are simultaneously present in the air, the presence of which causes multicomponent air pollution. The atmospheric pollution index, which is calculated for a group of substances, is often used as a complex indicator of the degree of air pollution. Currently, mostly applied methods of component-wise assessment of atmospheric air quality are used in practice. When calculating atmospheric pollution by boiler houses, the total volumes of fuel combustion products are determined experimentally or by calculation. This article provides empirical formulas for calculating the above standards – the volume of flue gases, the maximum one-time emissions of ash, sulfur oxides, carbon and nitrogen for various boilers with known technical characteristics. Also, using the above formulas, a comparative analysis of the level of air pollution depending on the quality of various types of fuel burned in various types ofboilers.