Russia has large coal reserves, on the average up to 173 billion tons. Although, the share of coal generation in Russia is relatively small (about 20–22 %), it reaches 65 % in the Siberian Federal District. Russia cannot deny coal, but it is necessary to update and improve energy efficiency of Thermal Power Plants (TPP) and boiler houses that burn coal. Currently, technologies have been developed to produce and use composite coal-water fuel (CWF) with various additives, primarily of organic origin to improve its target characteristics. A study of the characteristics of such coal-water suspensions has proved the promising outlook of their use as fuel in large and small Thermal Power Plants, both from an economic and environmental safety points of view. However, the lack of experimental data on the issues of combustion of composite coal-water fuel in bench-scale and semi-industrial conditions hinders the further development of CWF technology. Thus, it is relevant to study the features of combustion of composite coal-water fuels from coals of varying degrees of metamorphism. To prepare experimental batches of composite CWF, raw coals and coal slurries of various stages of metamorphism (grades D, SS, T) have been used. They were burned in a bench-scale semi-industrial plant. The research results have been processed using the methods of mathematical statistics and regression analysis. The influence of mechanical activation of CWF on the viscosity and temperature of its ignition and combustion has been established. The features of combustion of composite coal-water fuel using pneumomechanical injectors of two types are determined. The composition of harmful emissions during the combustion of CWF has been determined. The possibility to use composite coal-water fuel to ignite high-power boilers has been established. It has been proved that the combustion of CWF is environmentally safer compared to the combustion of coal and other types of fuel.

Использование угля из Межегейского месторождения (Республика Тыва) является перспективным направлением для производства тепловой энергии. Однако необходимо учитывать особенности технологических свойств угля, связанных с его повышенными характеристиками спекания. Указанные особенности по применяемой технологии слоевого сжигания угля приводят к перерасходу топлива из-за его недожога и высокому содержанию вредных веществ в отходящих газах. Город Кызыл уже включен в федеральный проект “Чистый воздух”, что свидетельствует об актуальности настоящего исследования и необходимости внедрения новых методов использования данного энергоресурса. Для снижения выбросов и повышения эффективности использования угля в энергетике целесообразно внедрение технологии получения и сжигания водоугольного топлива (ВУТ) с учетом специфических свойств данного угля. В работе установлена возможность получения и использования экологически чистого ВУТ из угля Межегейского месторождения. Проведен анализ технических характеристик угля, получена опытная партия ВУТ, определены характеристики сжигания этого топлива в котельной установке. Приготовление и сжигание опытной партии ВУТ было проведено на стендовой установке Сибирского государственного индустриального университета (Новокузнецк). Показано, что при использовании технологии сжигания ВУТ содержание вредных веществ в дымовых газах существенно ниже предельно допустимых значений. Развитие данной технологии использования угля Межегейского месторождения позволит снизить расход топлива на теплогенерирующих установках и уменьшить негативное воздействие на окружающую среду. The use of coal from the Mezhegey deposit (the Republic of Tyva) is promising for the production of thermal energy. However, it is necessary to consider the peculiarities of the technological properties of coal associated with its increased sintering characteristics. These features with the layered coal combustion technology lead to excessive consumption of fuel due to its underburning and a high content of harmful substances in the flue gases. Kyzyl has already been included in the Federal Project “Clean Air”, which indicates the relevance of the present investigation and the necessity of introducing new methods into the usage of this energy resource. To reduce emissions and to enhance the efficiency of coal use in power engineering, it is reasonable to introduce the technology of obtaining and burning coal-water fuel (CWF) taking into account the specific features of coal. The possibility of obtaining and using environmentally friendly coal-water fuel from the coals of the Mezhegey deposit located in the Republic of Tyva is established. The technical characteristics of coal were analysed, a pilot batch of CWF was obtained, and the combustion characteristics of this fuel in a boiler plant were determined. The preparation and combustion of the pilot batch of CWF was carried out in the laboratory installation at the Siberian State Industrial University (Novokuznetsk). It has been shown that the concentrations of hazardous substances in flue gases are substantially lower than the maximum permissible values. The development of this technology involving coal from the Mezhegey deposit will make it possible to reduce fuel consumption at heat generating installations and minimize the negative environmental effect.

Ирина ТАРАЗАНОВА Ведущий специалист Валентина ВОЛКОВА ЖУРНАЛ ЗАРЕГИСТРИРОВАН Федеральной службой по надзору в сфере связи и массовых коммуникаций.Свидетельство о регистрации средства массовой информации ПИ № ФС77

The article shows the possibility of efficient combustion of the products of enrichment and deballasting coal using low-temperature vortex technology of burning in boilers equipped with combustion chamber “Tornado”, which is implemented with joint flare-vortex grate and the burning fuel. This technology is applicable to virtually any kind of solid fuels and wastes. Due to the active aerodynamic structure of gas and fuel flows established in the furnace space, the vortex combustion technology can effectively reduce the sulfur oxides in the flue gas while burning high sulfur fuel. In this case, into the combustion space of the boiler is carried out simultaneous supply of fuel and sulfur-absorbing reagent (SAR). The article presents the research results of the possibility to suppress the release of sulfur oxides due to the suspension coal-water fuel (CWF) preparation with the simultaneous entry in the CWF along with the reagent-plasticizer of sulfer-absorbing reagent. The work is performed with the financial support of the State in the person of the Ministry of Education and Science of the Russian Federation within implementation of the Federal target program ‘Researches and Development on the Priority Directions of Development of Scientific and Technological Complex of Russia for 2014 – 2020’, as per the Agreement #14.583.21.0004 regarding Granting a Subsidy of July 16, 2014. The unique identifier of the scientific researches (project) of RFMEFI58314X0004.

The technology of coal preparation plants in modern Russia is characterized by using of closed water-sludge circuit to produce coal concentrate with the required parameters for moisture content without thermal drying of fine coal classes. However, as part of shipped rock to the dump fine waste of coal preparation class 0-0.5 mm appeared, usually represented by sludge filter presses - filter-cake. The outcome of filter-cake is up to 7 % by the weight of the processed coal [1]. The shipping of this product with the rock to the dump caused by the fact that its use is complicated by the high ash content of up to 50 % and the moisture content to 45 %. A similar situation exists in the LTD “Tugnuy PP” of JSC “SUEK”. The annual yield of the cake here is 800 thousand tones. For a solution of this problem, the reducing of the release of enrichment waste and increasing of the marketable products on Tugnuy coal preparation plant it was suggested to use the technology of production and combustion of coal-water slurry fuel (CWF) on semi-industrial installation. As a result 2 variants of filter-cake usage were suggested: - transfer on the CWF combustion boilers the existing boiler factory; - construction of mini CHP plants running on CWF, to provide electric and thermal energy needs of the Tugnuysky mine.