One of the factors which are usually difficult to be measured in mills is the grindability and distribution of feed under real situation and in a short time. In the condition of achieving a fast and convenient way to determine these parameters, the proper relationship between energy, hardness and particle size distribution can be obtained. Feed hardness is one of the most important factors in g...

13 The purpose of the study was to investigate the influence of torrefaction on the grindability of wheat straw. 14 Straw samples were torrefied at temperatures between 200 ̊C to 300 ̊C and with residence times between 0.5 to 15 3 hours. Spectroscopic information obtained from ATR-FTIR indicated that below 200 ̊C there was no obvious 16 structural change of the wheat straw. At 200-250 ̊C hemice...

Aiming at developing a dental titanium alloy with better mechanical properties and machinability than unalloyed titanium, a series of Ti-Nb alloys with Nb concentrations up to 30% was made. They were cast into magnesia-based molds using a dental casting machine and the mechanical properties and grindability of the castings were examined. The hardness of the alloys with Nb concentrations of 5% a...

Samples of torrefied wood pellet produced by low-temperature microwave pyrolysis were tested through a series of experiments relevant to present and near future waste to energy conversion technologies. Operational performance was assessed using a modern small-scale downdraft gasifier. Owing to the pellet's shape and surface hardness, excellent flow characteristics were observed. The torrefied p...

The efficiency of energy utilization in tumbling mills is discussed in terms of component processes taking place inside the mill. The past reports on the effect of physicochemical parameters of the environment on mechanical properties and grindability of materials are reviewed. Reported mechanisms explaining such effects are analyzed and possible ways to improve the grinding efficiency, through...

Grinding of a high volatile bituminous coal was performed in three comminution devices: Raymond Mill, Rolls Crusher and Ball Mill. The pulverised samples were sieved to obtain four particle size fractions and temperature-programmed combustion (TPC) was used for the evaluation of their combustion behaviour. In addition, three coals of different hardness and rank were mixed in various proportions...

Thermal pretreatment or torrefaction of biomass under anoxic condition can produce an energy dense and consistent quality solid biomass fuel for combustion and co-firing applications. This paper investigates the fuel characteristics and grindability of pine chips and logging residues torrefied at temperatures ranging from 225 °C to 300 °C and 30 min residence time. Grinding performance of torre...

High-voltage electrical pulses (HVEP) technology was applied in grinding of a magnetite ore as a comminution pretreatment. The effect of HVEP pretreatment on grindability, liberation and separation performance of a magnetite ore was investigated by a systematic experimental study. The results showed that the pretreatment of high-voltage electrical pulses created some intergranular microcracks i...

Ball mill is vital equipment in industries viz. mineral dressing, ore processing, fertilizers, food and diary, pharmaceuticals and many others. The present work involves a meticulous study of the effect of the various parameters on the performance of a ball mill. The parameters studied in this work are particle size, number of balls, time of grinding, particle density, and speed of the ball mil...