Control of the coal-rock boundary by elastic vibrations

Conclusions The marked difference between the rates of damping of longitudinal mechanical vibrations in metal rods brought into contact with specimens of coals and rocks gives grounds for assuming that this phenomenon may be utilized for remote discrimination between coals and rocks. This makes it possible to develop a special sensor for automatic control of the direction of movement of heading and extraction machines exactly along the boundary of the coal seam, i.e., along the boundary between the coal and rock. Donetsk Polytechnical Institute. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 5, pp. 124–128, September–October, 1975.     

用氮气和戊基黄药浮选时黄铁矿的低电位疏水状态

为了解释和查明N2TEC浮选法的基本原理，本文报道了在用戊基钾黄药(PAX)作捕收剂时，黄铁矿的低电位疏水状态的研究成果。新制定的N2TEC浮选法的目的是提高难处理含金硫化矿金回收率。在典型的N2TEC浮选法中，用氮气代替空气作为浮选气体，戊基钾黄药作为评选含金黄铁矿颗粒的捕收剂。l997年3月，第一个N2TEC浮选工艺在内华达州Lone Tree矿山浮选厂投产，一直操作至今。根据电化学校制接触角测量结果，研究了黄铁矿的低电位、低pH疏水状态与浮选变量(pH、气相组成、捕收剂浓度和黄铁矿电位)之间的关系。     

Minimierung der Umbauzeiten bei Stahlwerksmodernisierungen am Beispiel eines Stranggießanlagen-Umbaues

In November 2000 the Belgian stainless steel producer UGINE & ALZ Belgium nv, a company of the Arcelor Group, awarded VAI a contract for the upgrading and expansion of their steelmaking plant. The overall project included the revamping and supply of new equipment and systems for the steelmaking, continuous casting and environmental protection facilities. An essential part of this ambitious modernization program was the upgrading and expansion of the existing single-strand slab caster, with an output of 600 000 t/a, to a combined single- or twin-strand slab caster with a nominal production capacity of 1.2 million tons — the world’s largest stainless steel slab caster. All upgrading and installation activities had to be carried out within an extremely tight caster shut-down period of 21 days only in order to minimize production losses. This paper discusses the innovative project management solutions implemented in combination with extensive preassembly activities and workshop testing to assure the successful outcome of this project.