Development of advanced air-blown entrained-flow two-stage bituminous coal IGCC gasifier

Integrated gasification combined cycle (IGCC) technology has two main advantages: high efficiency, and low levels of harmful emissions. Key element of IGCC is gasifier, which converts solid fuel into a combustible synthesis gas. One of the most promising gasifiers is air-blown entrained-flow two-stage bituminous coal gasifier developed by Mitsubishi Heavy Industries (MHI). The most obvious way to develop advanced gasifier is improvement of commercial-scale 1700 t/d MHI gasifier using the computational fluid dynamics (CFD) method. Modernization of commercial-scale 1700 t/d MHI gasifier is made by changing the regime parameters in order to improve its cold gas efficiency (CGE) and environmental performance, namely H2/CO ratio. The first change is supply of high temperature (900°C) steam in gasifier second stage. And the second change is additional heating of blast air to 900°C. © The authors, published by EDP Sciences, 2017.This work was carried out at the Ural Federal University and Science Foundation (project no. 14-19-00524).financially supported by the Russia

Experimental and computational study and development of the bituminous coal entrained-flow air-blown gasifier for IGCC

In the paper the development of the advanced bituminous coal entrained-flow air- blown gasifier for the high power integrated gasification combined cycle is considered. The computational fluid dynamics technique is used as the basic development tool. The experiment on the pressurized entrained-flow gasifier was performed by "NPO CKTI" JSC for the thermochemical processes submodel verification. The kinetic constants for Kuznetsk bituminous coal (flame coal), obtained by thermal gravimetric analysis method, are used in the model. The calculation results obtained by the CFD model are in satisfactory agreements with experimental data. On the basis of the verified model the advanced gasifier structure was suggested which permits to increase the hydrogen content in the synthesis gas and consequently to improve the gas turbine efficiency. In order to meet the specified requirements vapor is added on the second stage of MHI type gasifier and heat necessary for air gasification is compensated by supplemental heating of the blasting air. © Published under licence by IOP Publishing Ltd.This work was financially supported by the Russian Science Foundation (project no. 14-19-00524)

Investigation of coal entrained-flow gasification in O 2 -CO 2 mixtures for oxy-fuel IGCC

Purpose of the study is to obtain fundamental knowledge about Kuznetsk bituminous coal entrained-flow gasification in O 2 -CO 2 mixtures for oxy-fuel IGCC. To achieve this purpose, it is necessary to carry out experimental and numerical studies. To obtain universal knowledge, "CKTI" single-stage gasifier with fuel consumption of 5-15 kg/h was chosen as an experimental installation. In order to identify the most interesting and informative experimental regimes, a number of computational studies have been carried out, whose results are given in the paper. A numerical (CFD) model has been developed, which includes all the submodels necessary for the study. Two series of numerical calculations were carried out. In the first series, the composition of the blast (O 2 = 0-100%, CO 2 = 0-100%) and the oxygen ratio were varied at constant consumption of coal and blast. In the second series, the composition of the blast (O 2 = 0-100%, CO 2 = 0-100%) and the coal consumption were varied at constant oxygen ratio and blast flow rate. The study allowed predicting and analyzing the temperature distribution and the syngas components content along the gasifier height with different CO 2 concentrations in the blast. © 2018 Institute of Physics Publishing. All rights reserved.Russian Foundation for Basic Research (RFBR

Study of the two-stage gasification process of pulverized coal with a combined countercurrent and concurrent flow system

The paper presents a numerical study of an advanced two-stage gasifier with a combined countercurrent and concurrent flow pattern and dry fuel feed system EAGLE. The Reynolds Stress model was used for the numerical simulation of turbulent flow. We have conducted studies on the influence of upper burner's inclination angle on heat and mass transfer processes in the gasifier as well as on coal conversion. It is shown that the increase in the upper burner's inclination angle in the horizontal plane allows intensifying the process of two-stage gasification. © 2017 The Authors, published by EDP Sciences.Problem statement and results analysis were carried out at the Ural Federal University and financially supported by the Russian Science Foundation (project no. 14-19-00524). The development of methods for mathematical modeling and calculations was carried out with the financial support of the Ministry of Education and Science of the Russian Federation under the Grant Agreement No. 14.607.21.0150 (Unique identifier of the RFMEFI60716X0150

Computational modeling of coal coke steam gasification process performed in thermogravimetric analysis device

Efficiency improvement of syngas generating equipment requires research of coal kinetic characteristics. A promising method for determining the kinetic properties of solid fuels is thermogravimetric analysis (TGA). The TGA device (in particular the furnace) is structurally complex and does not give a complete picture of all aspects of the process, such as aerodynamic features and the distribution of gases in the furnace volume. The method of computational fluid dynamics (CFD) allows to define these parameters. The report modeled the segment of the interior, as well as the space that washes the crucible itself.Для повышения эффективности работы оборудования, производящего синтез-газ, необходимо проводить исследования кинетических характеристик угля – дешевого и распространенного вида топлива. Перспективным методом определения кинетических свойств твёрдого топлива является термогравиметрический анализ (ТГА). Прибор ТГА (в частности печь) конструктивно сложен и не даёт полного представления обо всех сторонах процесса, таких как аэродинамические особенности и распределение газов в объёме печи. Метод вычислительной гидродинамики (CFD) позволяет определить данные параметры. В докладе моделировался сегмент внутреннего, а также пространства, омывающего сам тигель. Моделировались моменты на 80-ой, 102-ой и 126-ой минутах с начала эксперимента по газификации. Сравнение результатов, полученных для этих трёх случаев, позволило установить характер концентрационных полей каждого из газов.Исследование выполнено в Уральском федеральном университете за счет гранта Российского научного фонда (проект №14-19-00524)

Numerical study of the carbon dioxide dissociation influence in oxygen entrained-flow gasifier

One of the energy technologies and resource saving in coal-based energy considered in this work. Namely, entrained-flow gasifier, as a key element of combined-cycle plants with gasification. Numerical modeling of the national plant «NPO CKTI» carried out using computational fluid dynamics (CFD) method. The research of the entrained-flow gasification of solid fuel process was carried out without regard to and with due regard to high-temperature dissociate carbon dioxide process. The researches results of carbon dioxide dissociation process influence in oxygen entrained flow gasifier were described.В работе рассмотрена одна из технологий энерго- и ресурсосбережения в угольной энергетике, а именно поточная газификация твёрдого топлива в газификаторе - ключевом элементе парогазовой установки с внутрицикловой газификацией. Произведено численное моделирование отечественной установки ООО «НПО ЦКТИ» с использованием метода вычислительной гидродинамики CFD. Выполнено исследования процесса поточной газификации твердого топлива без учета и с учетом процесса высокотемпературной диссоциации углекислого газа. Описаны результаты исследования влияния процесса диссоциации углекислого газа в поточном кислородном газификаторе

The numerical research and aerodynamic characteristics comparison of the pilot flow gasifiers

В работе рассмотрена одна из технологий энерго- и ресурсосбережения в угольной энергетике, а именно поточная газификация твёрдого топлива в газификаторе - ключевом элементе парогазовой установки с внутрицикловой газификацией. В докладе сравниваются аэродинамические особенности работы двух пилотных одноступенчатых кислородных газификаторов под давлением с сухой топливоподачей пылевидного твёрдого топлива. Одна из этих установок разработана концерном Siemens, а вторая НПО ЦКТИ. Численное моделирование работы агрегатов проведено с использованием метода вычислительной гидродинамики CFD. Для сокращения времени расчёта геометрия исследуемых газификаторов была упрощена до сегментов в 5 и 45 градусов, соответственно. Произведено исследование расчетной сетки для газификатора Siemens. Сравнение расчётных результатов показало влияние относительных длин камер газификации на расположения аэродинамических структур.One of the energy technologies and resource saving in coal-based energy considered in this work. Namely, flow gasifier, as a key element of combined-cycle plants with nutriciology gasification. In the report the aerodynamic features of the two pilot single-stage pressurized oxygen-blown dry-feed pulverized solid fuels gasifier are compared. One of these units developed by concern Siemens, and the second - NPO CKTI. Numerical modeling of the units carried out using computational fluid dynamics (CFD) method. Simplified segments gasifiers geometries of 5 and 45 degrees, respectively, are studied to reduce the calculation time. The study was conducted of the computational grid for the Siemens gasifier. Comparison of the calculated results showed the influence of the gasification chamber relative lengths on the aerodynamic structures location.Исследование выполнено в Уральском федеральном университете за счет гранта Российского научного фонда (проект №14-19-00524)

Computational modeling of coal coke combustion process performed in thermogravimetric analysis device

Уголь является дешевым и распространенным топливом для производства энергии и синтез-газа, поэтому изучение его кинетических характеристик позволит серьёзно повысить эффективность работы оборудования. Перспективным методом определения кинетических свойств твёрдого топлива является термогравиметрический анализ (ТГА). Прибор ТГА (в частности печь) конструктивно сложен и не даёт полного представления обо всех сторонах процесса, таких как аэродинамические особенности и распределение газов в объёме печи. Данные параметры, как правило, определяют методом вычислительной гидродинамики (CFD). В докладе моделировалось внутреннее пространство печи, включающее тигли, подставку, держатель и трубку подачи защитного газа (аргона). В первом случае расчёт проводился для эксперимента с конечной температурой 4500С, а во втором – для эксперимента с конечной температурой 7000С. В обоих случаях один тигель был пустой, другой – с навеской кокса Кузнецкого каменного угля марки Д. Моделируемая система считалась изотермичной с температурами 4500С и 7000С и, соответственно, кинетическим и диффузионным режимами выгорания кокса. Сравнение результатов, полученных для двух вышеописанных случаев, позволило установить характер влияния режима горения кокса в одном из тиглей на аэродинамику и концентрационные поля внутри печи прибора ТГА.Coal is a cheap and videspread fuel for energy and syngas production, so the study of its kinetic characteristics allows to seriously improving the efficiency of the equipment. A promising method for determining the kinetic properties of solid fuels is a thermal gravimetric analysis (TGA). TGA instrument (particularly bake) structurally complicated and does not allow to experimentally determining some important process parameters such as aerodynamic characteristics, and distribution of gases in the kiln volume. These parameters are generally determined by computational fluid dynamics (CFD). The report modeled the interior of the furnace, including crucibles, stand, holder and tube shielding gas (argon). In the first case, the calculation was carried out for experiment with temperature of 4500C, and in the second – experiment with temperature of 7000C. In both cases one of the crucibles was empty and another with the sample coke Kuznetsk coal brand D. Simulated system is considered to be isothermal with a temperature of 450°C and 700°C and, accordingly, the diffusion regime burning coke. Comparing the results obtained for the above two cases, allowed establishing the nature of the influence of coke combustion process in one of the crucibles on aerodynamics and concentration fields inside the furnace TGA instrument.Исследование выполнено в Уральском федеральном университете за счет гранта Российского научного фонда (проект №14-19-00524)

The influence of gasifier operating parameters on syngas composition of coal-fired power plant with CO2capture

This work investigated the influence of the operating parameters of the gasifier (pressure, temperature of the syngas at the outlet of the gasifier and the O2/CO2 ratio in the blast) on the composition of the syngas in relation to the Allam cycles and oxy-fuel IGCC. Thermodynamic modeling of the operation of Shell (Allam cycle) and MHI (oxy-fuel IGCC cycle) gasifiers by the entropy maximization method was carried out. For the Shell gasifier, a significant increase in methane concentration with an increase in pressure to 40 MPa has been revealed; it indicates the need to make changes to the syngas gas cleaning system. The optimal temperature at the outlet of the gasifier (1100°C) has been found for the MHI gasifier. At this temperature, there were high values of CO and H2, and, hence, the heating value of syngas. For both gasifiers, the most theoretically reasonable ratio of O2/CO2 in blast was 0.3, at which CO reached almost maximum values and decreased its growth rate. © Published under licence by IOP Publishing Ltd.Government Council on Grants, Russian FederationThe work was supported by the Act 211 of the Government of the Russian Federation, contract № 02.A03.21.0006