The aim of this research was to produce a convenient additive for enhancing the properties, especially the fluid loss, of oil well cement slurries. In this regard, a variety of drilling/cementing chemical additives known as fluid loss controllers were prepared through derivatization and chemical modification of lignite. Lignite-based graft copolymers were synthesized using different groups of a...

Mining operations can drastically affect the stability of nearby areas. A representative case for this has been Mavropigi mine, a part an open-pit lignite mining complex in northwestern Greece. is vast excavation that reached 150 m depth and posed severe challenges issues caused problems area. In 2010, noteworthy surface tension cracks appeared near excavation, leading to extensive monitoring c...

Dissolved gases produce a gas pressure. This pressure is the appropriate physical quantity for judging possibility of bubble formation and hence it central understanding exchange climate-relevant between (limnic) water atmosphere. The contribution ebullition has widely been neglected in numerical simulations. We present measurements from six lacustrine waterbodies Central Germany: including nat...

partially replace oil and natural gas as fuel sources. Of all the coal-cleaning pmesses, flotation is one. of the most versatile. Carbon dioxide coal flotation is a new technology developed at the University of Utah.(l) Compared with conventional flotation, carbon dioxide flotation enhances the ash rejection and increases flotation recovery for coals of different rank with the exception of lign...

In this study, a circulating fluidized bed (CFB) of 125 mm diameter and 1800mm height was used to find the combustion characteristics of sewage sludge (SS) produced in Turkey. Sludge + olive cake, and sludge + lignite coal mixtures were burned separately. Various sludge-to-lignite coal and sludge-to-olive cake ratios (5/95, 10/90, 15/85, 20/80) were tried. On-line concentrations of major compon...