Study on Electrostatic Separation Process of Mixed Plastics from Waste Refrigerators

doi:10.19491/j.issn.1001-9278.2021.08.019

Abstract

Abstract:

A mixed plastic crushing material obtained from waste refrigerators was sorted to ABS and PS?HI waste plastics by free falling electrostatic separator. The effects of raw material pretreatment and electrostatic separator process on separation efficiency were studied through notched impact strength， tensile strength and separation efficiency. The results indicated that the efficiency of electrostatic separation and the properties of products were improved obviously through controlling the lower moisture content of mixed plastics. The optimal separation efficiency and product performance were achieved at a voltage of electrostatic separation field of 27 kV and a feeding speed if 550 r/min. The highest separation efficiency of ABS and PS?HI along with the best mechanical properties was achieved with electrostatic separator distances of about 200 and 220 mm， respectively.

Key words: waste refrigerator, mixed plastics, electrostatic separation, separation efficiency

CLC Number:

TQ317.9

LYU Huaixing, QIN Yufei, ZHAN Lu, NIU Yuanhang, XU Zhenming. Study on Electrostatic Separation Process of Mixed Plastics from Waste Refrigerators[J]. China Plastics, 2021, 35(8): 131-135.

Figures/Tables 6

Fig.1. Process flow chart of electrostatic separation

因素	取值					其他条件设定
W/%	0.5	0.4	0.3	0.2	0.1	U=24 kV	V=450 r/min	S=200 mm
U/kV	18	21	24	27	30	W=0.1 %	V=450 r/min	S=200 mm
V/r·min^-1	250	350	450	550	650	W=0.1 %	U=24 kV	S=200 mm
S/mm	180	200	220	240	260	W=0.1 %	U=24 kV	V=450 r/min

Tab. 1. Conditions of single factor experiment

Fig.2. Effect of water content on electrostatic separation of mixed plastics

Fig.3. Effect of voltage on electrostatic separation of mixed plastics

Fig.4. Effect of feeding speed on electrostatic separation of mixed plastics

Fig.5. Effect of electrode spacing on electrostatic separation of mixed plastics

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