Improvement of phosphorus removal from iron ore using combined microwave pretreatment and ultrasonic treatment

Abstract

Most of the past studies examined the effects of ultrasonic treatment on the removal of phosphorus, silica and alumina minerals from iron ores. In the present work, the effect of combined microwave pretreatment and ultrasonic treatment on the efficiency of disintegration and removal of phosphorus and other gangue minerals associated with iron ores has been studied. Three different iron ore samples have varying total iron concentration (TFe) and P 2 O 5 content and mineralogical textures were studied. Microwave pretreatment generated intergranular fractures between the gangues (fluoroapatite and chamosite) and oolitic hematite. These intergranular fractures improved liberation of iron ore, and accelerated ultrasonic disintegration and removal of phosphorus and gangue minerals from oolitic hematite. The results indicated that microwave pretreatment increases the efficiency of ultrasonic disintegration and removal of particles by about 20% compared to untreated sample. The results of ultrasonic treatment are quite promising. Significant increase in iron grade and reduction in phosphorus and alumina content of enriched product can be obtained. Depending on the sample texture and phosphorus distribution, about 59 % phosphorus removal can be obtained.

Microwave absorption properties of steelmaking dusts: effects of temperature on the dielectric constant (ε′) and loss factor (ε′′) at 1064 MHz and 2423 MHz

“…5 The use of microwaves, a form of electromagnetic radiation, as a heat source in material processing applications has become increasingly frequent over the past three decades. [6][7][8][9] Microwave heating is fundamentally different from conventional heating because microwaves take the form of electromagnetic energy and can penetrate deep into the sample. This allows sample heating to be initiated volumetrically as opposed to conventional thermal heating, which heats the sample from the outside in via standard heat-transfer mechanisms, i.e., through convection, conduction, and radiation.…”

Selective Zinc Removal from Electric Arc Furnace (EAF) Dust by Using Microwave Heating

“…The present study examines the possibility of selective zinc removal from EAF dust by means of microwave heating. The application of microwaves as a heat source in material processing has become increasingly frequent over the last three decades [7,[12][13][14]. Compared to conventional heating, microwave heating offers several advantages such as selective heating, rapid heating, and volumetric heating [15,16].…”

Characterization studies on Agbaja iron ore: a high-phosphorus content ore

“…As a consequence, a lot of research efforts have been focused on phosphorus removal from high-phosphorus iron ore [20,24,[32][33][34][35][36][37][38][39][40][41][42][43][44][45][46][47][48] in a bid to reduce the P content to acceptable levels. Processes that had been employed for phosphorus removal from iron ores include thermal treatment [7,21,24,[38][39][40][41][49][50][51][52][53], microwave treatment [38,[54][55][56], ultrasonic treatment [54], acid leaching [12,17,20,49,[56][57][58][59][60], alkaline leaching [5,59], bioleaching [30,[61]…”