Current Aspects of Prevention of Coal Freezing by Means of Inorganic and Organic Reagents

In the cold season, irregular coal supplies to coke plants are aggravated by the need to heat the coal cars. Thawing of rail cars in garages (enclosures) is the least efficient and most expensive approach. Treatment of the coal concentrates with chemical additives reliably prevents freezing in winter during transit from suppliers to consumers. With a view to finding new reagents for preventing the freezing of coal in winter, the lime, the acetates and chlorides of alkaline-earth and alkaline metals are studied. Attention focuses on their physicochemical characteristics, methods of preparation and of introduction in coal concentrate, and their influence on freezing. The results of studies have shown that the use of organosilicon is more effective use of acetates and chlorides of metals. The high activity of organosilicon substances is explained by their elemental composition and structure of molecules.

Impact of transportation on foundry coke quality

The quality metrics of foundry coke are determined by testing at coke plants. Foundry coke consumers are foundry enterprises which are usually located far from the coke plants. Foundry coke is transported in bulk in open railway wagons. Therefore, this paper is aimed to determine the impact of transportation on the quality of foundry coke. The test conditions were as close as possible to real life conditions of foundry coke transportation. To estimate the impact of transportation distance we introduced the destruction index Pт (%). The results of experimental studies have shown that the destruction of foundry coke is not the same at different intervals of transportation. When transporting up to 300 km, the coke with the minimum durability index M40 is destroyed. When the distance is increased from 900 km up to 2500 km, the foundry coke destruction index (Pт , %) increases by 2.08 – 3.02 % depending on the batch. For all batches, a size fraction of less than 40 mm was noted depending on the durability index M40 from 0.25 to 1.41 %. The size fraction of more than 80 mm stays the same for foundry coke with higher durability indices. When the air humidity rises by 40 % during transportation, the amount of moisture in the coke samples of a 40 – 60 mm size fraction is more than 24 times higher than usual, a 60 – 80 mm size fraction – more than 17 times, an 80 mm and larger – more than 10 times. When the air humidity decreases by 34 %, the amount of moisture in a gram of coke of a 40 – 60 mm size fraction becomes 2 times lower than usual, a 60 – 80 mm size fraction – 1.26 times, an 80 mm and larger – 1.45 times. Compared to coke of size fractions 60 – 80 mm and 80 mm and larger, the moisture of the 40 – 60 mm size fraction coke grows faster when the air humidity increases as well.

WATER BALANCE AT PLANTS IN TECHNOLOGICAL SOLUTIONS ENGINEERING

In this paper questions and conditions of water management in the water-circulation systems taking into account water losses on the example of the coke-chemical plant are considered. The water balance of the primary gas refrigerators cycle at the Kharkiv coke plant has been calculated and compiled, taking into account the proposed technological solutions. As a result of the operation of the water-circulation systems, it was found that the water loss for evaporation at the Kharkiv Coke Plant is on average 2% in winter and 3% in summer. Water losses in the system are replenished with fresh technical water and purified phenolic wastewater. Technical appraisal of the work of heat-exchange equipment at coke plants is carried out consists of replacing part of fresh technical water with phenolic wastewater and minimizing wastewater discharges. The purpose of the project is to create conditions for the water re-use by coke-chemical plants and to predict its water balance depending on the technological decisions made. Thus, the purge of the system is 5.6 m3/hour, while the total irreparable water loss in the system is 9.4 m3/hour. In the article it is established that the application of the proposed technical solutions allows to reduce the amount of discharge of sewage into urban sewer network at 36 000 m3/year and consumption of fresh industrial water to 52 000 m3/year, and increase the service life of equipment from 6.5 to 8 years. These measures help to improve water and environmental situation, effective water management of the coke-plant, that is, to decrease the payment made for consumption of water resources and sewage plant. The presented water balance and calculations of losses of water in the reverse water supply system of the enterprise are executed prove positive effect from the proposed technology solutions. Keywords: phenolic water-circulation systems, coke plants, water management, water balance

PREDICTION OF STABILITY OF THE CIRCULATING WATER

In the work, on the basis of the data of the analysis of theoretical works and the laboratory studies carried out, the prediction of the values of corrosion rates in the circulating systems of coke plants was carried out using the Langelier and Ryznar stability indixes. The laws governing changes in the thermal stability of water as a function of temperature and water quality indicators (pH, alkalinity, total salinity, calcium ion content) have been established. Analysis of the obtained data showed that there is a clear dependence of the scale-corrosion properties of water on temperature and its chemical composition. A stable and effective supplying water composition for the circulating water supply system of the Kharkiv Coke Plant has been established.

An Analysis for Coal Transportation and Demand in US and International Markets

Since coal resources are located around the world and often far away from where the coal is consumed, transportation is important. The industries that use coal such as power plants, industrial plants, coke plants, and commercial institutions usually prefer different transportation methods. The demand in these industries and the transportation methods they use differ over time. This chapter analyzes the international coal transportation and demand. An analysis for the US coal market and the transportation to industries along with the methods that are used between 2001-2015 are presented. A trend analysis was performed to show the long-term demand for each transportation method in each industry. Such analysis is also useful as it allows observing the coal demand from each industry. Analysis results reveal the change in coal amounts that are transported to each industry using the railroad, truck, and other methods.

Thermal-detoxification equipment and utilization of heat from cokebattery smokestack gases

Kotloenergoprom Stock Co. has developed new technology of thermal rendering harmless andwaste recovering of heat of flue gases from coke-oven batteries in one unit.In 2000, Kotloenergoprom Stock Co. had executed the design of the first in the world Unit ofthermal rendering harmless and waste recovering of heat of flue gases from the coke-oven batteryNo. l installed in "Zaporozhkoks" (65 furnaces, H = 7.0 m, V = 41.6 m3).The complex "Coke-oven battery - Unit" operates in the special mode using automatic processcontrol system. Introduction the above Unit in 2002 had ensured: decrease of NOx contents influe gases from coke-oven battery in 1.5+2 times and CO on 90+ I 00 % with providinginternational norms of ejections; rebuming solid carbon inclusions and combustible components(H2, CH4, CmHn) in flue gases; stabilization of hydraulic mode of coke-oven battery operation;non-shock putting coke-oven battery into operation directly to chimney stack in case of scheduledor accident stopping the Unit; waste recovery of heat of flue gases from coke-oven battery inquantity up to 6.0 Gkal/h; producing up to 85 tph of steam with energetic parameters at additionalcombustion of coke-oven gas (without building new chimney stack), that lets to produceadditionally 6 MWt of electric power;Standard scheme of producing heat and electric power at by-product coke plants applying usualboiler houses and power stations is irrational. The more effective is to apply the scheme ofproducing heat and electric power with simultaneous rendering harmless and waste recovery ofheat of flue gases from coke-oven batteries in the special Units using existing chimney stacks ofcoke-oven batteries.Cost of building the Unit is not more than cost of usual boiler house or power station with equalcapacity.