US EPA

2780428 

Journal Article 

Recycling steel from grinding swarf 

Fu, H; Matthews, MA; Warner, LS 

1998 

1 

Waste Management
ISSN: 0956-053X
EISSN: 1879-2456 

BIOSIS/99/07730 

18 

5 

321-329 

English 

WOS:000078503900004 

BIOSIS COPYRIGHT: BIOL ABS. Two cleaning processes have been investigated for removing contaminants (cutting oil with phosphorous ester) from high speed steel (HSS) grinding swarf. One process uses an aqueous surfactant washing technique, and the second process uses supercritical carbon dioxide (SCCO2) extraction. Both technical and preliminary financial analysis are performed to have a better evaluation of these two competing cleaning technologies. Bench scale aqueous washings have shown that the required phosphorous removal is easily obtained, but a sufficient oil removal is more difficult. The experimental results also indicate a strong dependence of the aqueous washing efficiency on the choice of a suitable surfactant. SCCO2 extraction at 80� C and 340 atm shows that approximately 80% of the oil can be removed from swarf during a 60-minute process to produce a batch of recyclable steel, and that the phosphorous removal also reaches the required level. The cost of processing swarf using either 

steel grinding swarf; aqueous surfactant washing; supercritical carbon dioxide extraction; recycling steel