Early Pumping Engines in the Attercliffe-Darnall-Orgreave coalfield and the role of John Curr

By the mid-1700s, Attercliffe had a developed into a major industrial centre, specialising in steelmaking, and distinct from the town of Sheffield. It also had its own coalfield, which included the Barnsley Coal, valued for its steel-melting coke. The first ‘engine-drained’ coal pit at Attercliffe opened in 1747, close to the River Don and the Sheffield road. It was succeeded by a sequence of further collieries, each following the crop of the Barnsley Coal progressively eastwards towards Orgreave. Development of underground workings by separate, competing partnerships was uncoordinated, and all the collieries faced a constant struggle with inflowing water, including leakage between properties through failed barriers. Nine Newcomen-type pumping engines were eventually erected in this small coalfield during the remainder of the eighteenth century, two of which were also fitted with flywheels for coal-winding. A further four engines, of presumed Newcomen-type, were also erected for winding only. Four of the pumping engines were designed by John Curr, including the Greenland engine, which is described in detail in his book. He also designed and manufactured one of the winding engines.

FABRICATION OF PROTECTIVE SiC/TiO2/SiO2 COATINGFOR GRAPHITE ELECTRODES

Today, there is a rapid growing demand for graphite electrodes used at steel making factories. Graphite electrodes are expensive materials that are used at steel making factories. Increasing the working longevity of these materials can significantly improve the benefit of steel melting process. Therefore, the increase in the stability of graphite at high elevated temperatures in electric arc furnaces is necessary. The mixture of SiC/TiO2/SiO2 coating can desirably reduce the oxidation of the graphite matrix at high temperatures. Evidently, the SiC/TiO2/SiO2 coating can specially decrease the mass loss rate of the graphite at high elevated temperatures and improve its working longevity in these conditions. Moreover, this coating can effectively improve the stability and thermal shock properties of graphite at the temperatures up to 1000∘C.

Ensuring the eco safety of mixing departments steel melting shops

Introduction. Mixer branches of metallurgical enterprises are an intermediate link between blast furnace and steelmaking workshops. They are equipped with mixers – footer containers for storing cast iron melt. In Ukraine, mixers with a capacity of 1300 or 2500 tons are used. Technological operations are accompanied by emissions of finely dispersed brown smoke and large-dispersed graphite dust into the atmosphere. Problem. Mixer compartments of Ukrainian factories are equipped with aspiration systems that dimity emissions from cast iron pouring and draining units with the help of fume tubes, then emissions pass the dust collector and discharge into the atmosphere through a chimney. The main impact of mixer compartments on the environment is: disorganized emission through an aerodynamic dust lamp, which is not allotted by the aspiration system; organized emission through a smoke pipe of dust not caught by a dust collector; solid waste from gas cleaning and dust hoppers settling on the floor and structures of the mixer compartment from the disorganized ejection that did not come out through the lantern. The main problems are insufficient aspiration (disorganized emission) and low emission purification efficiency (emission through the chimney). A separate problem is the disposal of caught dust. The degree of aspiration in the factories of Ukraine is about 0.7 for the filling unit in the mixer and 0.8 for the drain unit from the mixer at the power of the aspiration system 150-250 thousand tons. This does not meet modern requirements. Results. Cyclones are used as a dust collector in most factories, which completely capture graphite, but are not effective enough for brown smoke. Therefore, it is proposed to use sleeve filters or electro filters. It is also possible to introduce the suppression of brown smoke with nitrogen. The use of nitrogen is possible in accordance with cyclones (for existing systems) or compatible with filters (during reconstruction or new construction). The use of suppression of brown smoke with nitrogen allows to solve the problem of disposal of caught dust, because nitrogen supply leads to enrichment of dust with graphite. The content of graphite increases from 15% to more than 30%, which converts dust from care to commodity product. Keywords: mixer, cast iron pouring, cast iron drainage, dust suppression by nitrogen, aspirational mixer compartment system.

Development of Supplements Prevention System in Oxygen Converter Process in Order to Increase the Economic Efficiency of Steel Melting

The article analyzes the work of the oxygen-converter shop of PJSC «ArcelorMittal Kryvyi Rih». It is shown that almost half of the total number of blowing supplements (~ 44%) is carried out by temperature. In order to improve the conditions of steel smelting and reduce resource costs, calculations were performed and new technological solutions were found in steel smelting to reduce the number of additives. The study of real smelters demonstrated the need for corrective operations in the smelting of steel using scrap metal of different types. Scrap smelts have a clear relationship between the amount of scrap in the charge and the temperature of the melt in the first dump. The addition of «goat» scrap to the charge has a number of uncontrolled effects on the process due to significant fluctuations in the chemical composition of this type of metal charge. An economic analysis with introducing the developed control mechanism over the course of steel smelting into the software system for conditions PSJC «ArcelorMittal Kryvyi Rih» was performed.

Efficiency Estimation of the Bacal Siderites Using to Increase Stability of Steel-Melting Agregates Lining

During the melting processes in steel-melting aggregates, lining destruction takes place due to the Magnesium oxide of lining dissolution in slag. In this study, different materials containing Magnesium oxide have been introduced into slag to increase lining stability. Efficiency estimation of raw siderite (10-0 mm class) using for this aim is considered in the present work. Initial slag (basic capacity СаО/SiO2=2,1) of industrial ASM (Arc Steel Melting) was corrected by high magnesia introduction additives (siderite). Slag has been loaded into a magnesia crucible, heated up to 1700∘C, aged during 1 hour and cooled with the furnace. The final slag phase composition analysis detected considerable changes in it: increase of MeO-phase refractory with MgO prevalence (melting temperature 2800 ∘С) and replacement of monocellitic silicate component (CaO⋅MgO⋅SiO2, melting temperature 1498 ∘С) by larnite (β-2CaO ⋅SiO2 melting temperature 2130 ∘С). Crucible slag resistance was estimated by thinning of it walls. Experiment results confirmed affect of MgO content in slag to linings solubility in it. It was determined that siderite additives increase MeO-phase (melting temperature more than 2000 ∘С) content in slag approximately by 30 % that is rather essential for lining service period increasing. It is confirmed that siderite additives prolongate magnesia lining stability of steel-making aggregates. Keywords: Bacal siderite, refractory lining, steel-making aggregates, crucible, monocellit, magnesia