Russian Coal Research Articles

The effect of O 2 enrichment on NO x formation in biomass co-fired pulverised coal combustion

Oxygen enrichment of the combustion air in pulverised coal combustion for power plant is seen as a possible retrofit measure to improve CO 2 scrubbing and capture. This technique produces a reduced volume of flue gas with higher CO 2 concentration than normal air combustion that will contributes to the enhancement of amine scrubbing plant efficiencies. We report in this article the results of a study at the small pilot scale into the effect of these combustion modifications on the formation of NO x and associated carbon burnout changes. Experiments were performed using a Russian coal, typical of that used in some UK power stations with shea meal and Pakistani cotton stalk as biomass fuels co-fired at a fraction of 15%th. The down-fired pulverised coal combustor was operated at 20 kWth under air-staged conditions for NO x control and the secondary and over-fire air flows were both enriched by up to 79% (100% O 2) for a range of splits giving a 35% overall O 2 concentration for full enrichment. When the same enrichment process was applied to biomass/coal combustion different behaviour was observed with respect to NO x formation. We have shown that oxygen enrichment can achieve benefits of improved carbon burnout with a positive impact on NO x emissions over and above the primary aim of increasing CO 2 concentration in the flue gas for enhanced capture efficiencies. With all other conditions of overall stoichiometry, OFA levels and O 2 enrichment levels remaining the same, NO x levels at 22% OFA initially increased over the range of secondary air enrichment, particularly for shea meal/coal co-firing. At 31% OFA the trends were to lower NO x at high enrichment levels. However, co-firing with shea meal initially showed an increase in NO x emission at lower levels of enrichment (up to 40% O 2) followed by overall lower NOx emissions at 100% O 2 in the secondary air. The results show that NO x emissions can either increase or decrease depending on the operating conditions. The differences in behaviour are attributed, not only to the effects of enrichment on the stoichiometry of the near-burner zone, but also on the flame dynamics and intensity of combustion related to the associated reductions in gas velocity and swirl intensity by the transition from air to pure O 2 in the secondary oxidant stream.

Russian coking coal in 2008 and 2009

Russian coking coal in 2008 and 2009

Parameters for optimization of coke quality (CRI and CSR)

Experimental data illustrate the diversity of ash composition in Russian coal, even within a single rank. Examples show that the ash basicity may be used for effective optimization of the coking-batch composition by basin, rank, and components, in improving the CRI and CSR values of coke.

Potential benefits of experimental modelling techniques when assessing combustion behaviour of a suite of coals

AbstractSince coal will remain a major source of fuel for power generation for the foreseeable future, it is important for users to maximise their efficiency from the currently available markets. Russia is a dominant supplier to the UK at present, and burnout is known to vary considerably, depending on the source. In this study, eight Russian coals in pulverised size (75% less than 75 μm) were characterised using standard techniques, non-traditional image analysis techniques and with a combustion modelling approach (ChB), in order to predict burnout characteristics. These coals were then pyrolysed in a drop tube furnace, at 1300°C, 150 ms and 1% oxygen, and the subsequent chars characterised for reactivity and morphology. The chars were then refired in order to assess burnout propensity at 1300°C, 5 vol.-% oxygen and 600 ms. The results show that the ChB modelling technique can accurately predict burnout performance of unknown coals and may provide a cost effective approach to assess coal combustion perfo...

Russian coking coal

Russian coking coal

Russian metallurgical coal supplies. A near-term perspective

Calculations were made to estimate the changes in metallurgical coal supplies during the next 10 years. These calculations are based on three sets of data for the forecast period: (1) estimated changes in production at existing coal production and cleaning facilities in Kuznetsk, Pechora, and South Yakutsk basins; (2) production from new facilities as stipulated in licensing agreements for metallurgical coal production; and (3) Russian output of coke and washed coals. Estimates are given for two years: 2010 and 2015. A two-year base period of 2004 and 2005 was chosen because production was low in 2005 due to poor market conditions in the metal industry.

IRON SUPPLY OF CUCUMBERS IN SUBSTRATE CULTURE WITH HUMATE

IRON SUPPLY OF CUCUMBERS IN SUBSTRATE CULTURE WITH HUMATE

The Russian Coal Industry in Transition: A Linear Programming Application

This paper analyses the restructuring of the Russian steam coal market. The main purpose is to compare the prevailing steam coal flows between mine basins and electric utilities and the actual coal prices with those that would prevail in an efficient market. The analysis is done within a short‐run linear programming model. Coal demands and supplies are identified. The objective function that is minimised consists of the delivered costs, i.e. extraction plus transportation costs, subject to exogenous demand requirements and capacity restrictions. We conclude that, in spite of attempted restructuring, the Russian coal steam coal market is still highly inefficient. This is mainly due to the fact that large amounts of coal are delivered over very long distances, a pattern that often cannot be justified in economic terms. Because of cost‐inefficient coal deliveries and large subsidies, coal prices are also highly distorted. Given the communist legacies of the past, the restructuring process will probably take considerable time and is unlikely to be successful until there is a fundamental change in the economic and political institutions.

中国および日本で使用される石炭と石油の硫黄同位体比

Sulfur isotope ratio ({delta}-{sup 34}S) was measured for coals and oils used in northern China, eastern Russian and Japan. The {delta}-{sup 34}S values of northern Chinese coals and Russian coals are 7.7 {+-} 11.4 parts per thousand (about 5 parts per thousand in median) and 4.5 {+-} 4.85 parts per thousand in average, which are higher than those reported for coals in southern China. This suggests the difference of coal forming processes between northern China, eastern Russia and southern China. Oils (main fuel in Japan) show low {delta}-{sup 34}S values that are very different from those of Chinese and Russian coals. These differences in sulfur isotope ratios are reflected to the seasonal variation of sulfur isotope ratios of rain and aerosol in the Japan Sea side of Japan.

98/01815 Possibility of the use of the international classification of coals in beds for evaluation of Russian coal fields : Eremin, I. V. and Bronovets, T. M. Khim. Tverd. Topl., 1997, (1), 3–10. (In Russian)

98/01815 Possibility of the use of the international classification of coals in beds for evaluation of Russian coal fields : Eremin, I. V. and Bronovets, T. M. Khim. Tverd. Topl., 1997, (1), 3–10. (In Russian)

97/04828 Experience with combustion of nonstandard grades of Russian coals in boilers of the Sverdlovenergo Thermal Power Plant: Karyagin, Y. et al. Elektr. Stn., 1997, (6), 2–9. (In Russian)

97/04828 Experience with combustion of nonstandard grades of Russian coals in boilers of the Sverdlovenergo Thermal Power Plant: Karyagin, Y. et al. Elektr. Stn., 1997, (6), 2–9. (In Russian)

97/04000 Effect of burner design on combustion and SH/RH spray performance

Co-firing of biomass residues with coal is continuously increasing in it’s application in coal-fired boilers for electricity production. In this study, co-firing experiments were performed using a Russian coal with a range of biomasses, shea meal (SM), cotton stalk (CS), sugarcane bagasse (SBT), sugarcane bagasse (SBR) and wood chips (WC) as biomasses in 5%, 10% and 15% thermal fractions to evaluate their potential as substitute fuel and an agent for NOx control. It was found that the addition of biomass increased NO reduction under both un-staged and air-staged conditions. However, NO reductions obtained under optimum conditions of primary zone stoichiometry (SR1 = 0.9) and over-fire air (OFA) injection port location 3, were found to be significantly higher than un-staged co-firing for the same biomass thermal share in the fuel blend. It was found that the addition of biomass has a positive effect on carbon burnout under the optimum conditions that were determined in the study. A 10% biomass blending ratio (BBR) was found to be optimum for air-staging conditions. When co-fired under optimum air-staged conditions, a 10% BBR of sugarcane bagasse (SBR), shea meal (SM), wood chips (WC), cotton stalk (CS) and sugarcane bagasse (SBT) in coal gave NO reduction of 49%, 51%, 53%, 60% and 72%, respectively.

97/02924 Concentrations of inorganic elements in biomass fuels and recovery in the different ash fractions

In this study, a numerical investigation on the radiative and convective performance of the combustion of pulverised Russian coal having higher Calorific value in a 0.5 MWth combustion test facility (CTF) has been conducted for air and CO2-rich oxy-fired environment considering an IFRF Aerodynamically Air Staged Burner (AASB) configured with the furnace. This study is carried out considering a finite volume method (FVM) tool using AVL Fire version 2009.2 coupled with the user defined subroutines especially for the coal devolatilisation and char combustion modelling. This code is validated comparing the experimental radiative heat flux with the numerically predicted data and results show that reasonable agreement has been found with the measured radiative heat flux on the furnace wall. Different combustion environments were investigated including an air-fired as reference case and three recycled flue gas (RFG) fired combustion environments. The different cases are composed of varying recycled ratio (RR) between 65% and 75%. It was found that the flame temperature distribution for the reference case (air fired) and RR72% case were found to be similar. The flame temperature increased with O2 concentration and decreasing RR. With the decrease of RR, the length of the flame is also shortened. The ignition condition improved with enriched O2 concentration in the RR65% (O2 30.9%, CO2 69.2% by mass) case. The results show that radiative and convective heat flux is significantly manipulated by the RR. The position of peak radiative flux moves downstream with increasing RR due to increased mass flow rate and reduced O2 at higher RR. With the increase of normalised total flow (NTF), mean flame temperature and exit temperature decreased whereas with the increase of normalised O2 flow (NOF), mean flame temperature and exit temperature increase. The presented working range for the Russian coal, suggests that the air equivalent radiative heat flux can be obtained at a RR of ≈71% while air equivalent flame temperature were observed at RR of 72%. Reasonable agreement has been obtained for unburned carbon in ash (CIA). An improved burnout was observed in RR conditions.

97/02917 Biomass-derived oxygenates for transportation fuels

In this study, a numerical investigation on the radiative and convective performance of the combustion of pulverised Russian coal having higher Calorific value in a 0.5 MWth combustion test facility (CTF) has been conducted for air and CO2-rich oxy-fired environment considering an IFRF Aerodynamically Air Staged Burner (AASB) configured with the furnace. This study is carried out considering a finite volume method (FVM) tool using AVL Fire version 2009.2 coupled with the user defined subroutines especially for the coal devolatilisation and char combustion modelling. This code is validated comparing the experimental radiative heat flux with the numerically predicted data and results show that reasonable agreement has been found with the measured radiative heat flux on the furnace wall. Different combustion environments were investigated including an air-fired as reference case and three recycled flue gas (RFG) fired combustion environments. The different cases are composed of varying recycled ratio (RR) between 65% and 75%. It was found that the flame temperature distribution for the reference case (air fired) and RR72% case were found to be similar. The flame temperature increased with O2 concentration and decreasing RR. With the decrease of RR, the length of the flame is also shortened. The ignition condition improved with enriched O2 concentration in the RR65% (O2 30.9%, CO2 69.2% by mass) case. The results show that radiative and convective heat flux is significantly manipulated by the RR. The position of peak radiative flux moves downstream with increasing RR due to increased mass flow rate and reduced O2 at higher RR. With the increase of normalised total flow (NTF), mean flame temperature and exit temperature decreased whereas with the increase of normalised O2 flow (NOF), mean flame temperature and exit temperature increase. The presented working range for the Russian coal, suggests that the air equivalent radiative heat flux can be obtained at a RR of ≈71% while air equivalent flame temperature were observed at RR of 72%. Reasonable agreement has been obtained for unburned carbon in ash (CIA). An improved burnout was observed in RR conditions.

Economic Aspects of Russia's Coal Reserves: Key Statistics

Recently published statistics by the EEC and by IEA Coal Research shows that there is only a small proportion of Russian coal reserves which has export potential. It is possible that Russian coal exports will cease to be a significant part of world coal trade.

96/04720 Russian coal: Free market or free fall?

This paper develops a real options model of a price-setting cartel under uncertainty to examine whether market demand volatility facilitates collusion or not. We show that there is a critical level of market demand (the optimal defection trigger) above which firms find it desirable to defect from the cartel. We show further that an increase in the underlying market demand uncertainty has two opposing effects on the optimal defection trigger. First, the increased market demand volatility gives rise to the usual positive effect on option value that lifts up the optimal defection trigger. Second, the increased market demand volatility calls for an upward adjustment of the discount rate and thus creates a negative effect on option value that pushes down the optimal defection trigger. We show that the negative effect dominates (is dominated by) the positive effect when the underlying market demand uncertainty is trivial (significant), thereby rendering a U-shaped pattern of the optimal defection trigger against the market demand volatility.

96/03505 Regularities of chlorine concentration and form location in Russian coals

96/03505 Regularities of chlorine concentration and form location in Russian coals

Origins of Labor Policy in the Russian Coal and Steel Industry, 1874–1900

In the southern Russian coal and steel region between 1874 and 1900, labor policy was outlined by the Russian managers of predominantly foreign firms through the Association of Southern Coal and Steel Producers. This policy was shaped by chronic labor shortage, by the strained relations between industry and local government, and by managers' sensitivity to their position as spokesmen for foreign interests. The posture southern managers developed was that of welfare capitalism. Considerable expenditure on wages and welfare, however, did not establish labor peace.

Indiana Paper Coal: Composition and Deposition

ABSTRACT The term previously applied to a coal in the U.S.S.R., describes a coal found in Parke County, Indiana. In contrast to the Russian coal, which consists of cuticles of arborescent lycopods, the cuticles of the Indiana paper coal resemble Sphenopteris bradfordii Arnold, the foliage of a seed fern. Exinite (cuticles and spore exines) constitutes 23.5 percent of the coal seam where it is unweathered. The papery texture occurs only where weathering has removed the vitrinite and has left a mat of resistant cuticles. Spore analyses indicate that the seam is one of the upper Pottsville coals. Many sporangia from the paper coal are composed of small, round non-sutured spores and an outside layer of spores resembling Torispora Balme. Cutinization suggests that these plants could store water. Fresh water periodically feeding into a saline swamp could have been adequate to sustain these xerophytic plants. Trace element analyses substantiate the belief that water conditions were predominantly marine. Cutinite isolated from the coal has a calorific value of 16,700 B.T.U. per lb and a volatile matter content of 85 percent on a dry, ash-free basis. Because cutinite has such a high volatile matter content similar cuticular coals possibly can be utilized most efficiently as hydrocarbon sources.

On the Russian coals from the basin of the River Don, investigated by messrs. Scheurer-Kestner and Meunier-Dolfus

On the Russian coals from the basin of the River Don, investigated by messrs. Scheurer-Kestner and Meunier-Dolfus