The invention belongs to the technical field of
brown coal quality improving, and relates to a large-scale
brown coal quality-improving process and a large-scale
brown coal quality-improving apparatus. According to the invention, an interrelated large-scale continuous brown
coal quality-improving
system is composed of three modules which are a tunnel internal-heat
drying module, an external-heating
microwave destructive distillation module, and a powdery brown
coal molding and
drying module. Because of large-amount water discharging, a brown
coal block large-capillary framework is collapsed, so that the brown coal is naturally broken into small blocks and
powder without mechanical disruption. The small-block brown coal is subjected to
destructive distillation under high-temperature hot wind external heating and
microwave coupling, until the blocks turn into semi-
coke; water-containing
coal gas, water-containing
coal tar,
anhydrous gas, and
anhydrous coal tar are respectively obtained by
destructive distillation. With a binder of the water-containing
coal tar and coal
tar pitch (one or a mixture thereof), the powdery brown coal is subjected to kneading and aging; the material is processed into granules by using a vacuum
extrusion granulator; and the particles are processed by using a low-temperature
microwave drying device, so that high-quality brown coal particles with high strength, low
moisture absorption, and
high heat value are obtained. The brown coal particles can endure long-distance transportation.