Study on Enhanced Fine Particle Filtration Performance Based on High-Pressure Air Blowing
摘要
With the growth of global energy demand and pursuit of green economy, clean utilization of coal resources is becomng increasingly important. Coal slurry dewatering is one of the most important unit operations in the coal cleaning process. We investigated the effect of positive-pressure air blowing on the enhanced dewatering of fine particles. First, the characteristics of samples were studied by industrial and elemental analysis, XRD, and contact angle test. Moisture of the filter cake decreased from 27.15% to 14.23%, when aeration time was extended from 32 s to 90 s. Filtration pressure was increased from 0.2 MPa to 0.5 MPa at the same aeration time, and filtration time was shorter under higher pressure condition, while the remaining blowing time was longer. The moisture was 19.81%, 16.79%, 14.81%, 14.51% and 14.35%, respectively. After the pressure was increased, solid particles were deformed and rearranged, and particles were more closely packed. The specific resistance α of filter cake increased from 2.7214 × 1010 m/kg to 3.6294 × 1010 m/kg, which hindered gas blowdown. This study provides a new theoretical basis for the field of fine particle dewatering, which can help blow air-enhanced dewatering to become a new dewatering method of industry with high efficiency and low cost.