Regarding Shredders, we made our own machine which had some problems initially, but has been working quite well for the
last 3 years now. Here is a brief summary.
Summary of shredder development:
- we built three models based on units we saw in Phillippines
- first two the motors were appearently too small. Now with 18hp Chinese diesel seems about right. Can process about 4 m3 of mixed waste per hour.
- All units used horizontal rotating knives made from truck springs.
- An engineer told me once that if knife end speed is above a speed (45meter per second I think) then action is more shattering than
cutting. I think we must be in that zone because we have not sharpened the blades in about one year and still seems to work OK.
- Drum diameter is about 0.65m I seem to remember
- we use a right-angle gear box made from a Mercies car rear axle.
- I think we use 3 double-ended rotating knives and 4 or more stationary
knives fixed to interior of the drum.
- There is one double-ended ejector blade at the bottom to eject the
shredded material.
See photos attached.
WASTE SHREDDER
NEW SHREDDER
SHREDDER
SHREDDER TOP OFF PHILIPPINES
SK AND RD WITH EARLIER MODEL
Robert Deutsch robdeutsch@bigpond.com.kh
Advisor, Community Sanitation and Recycling Organization
Phnom Penh, CAMBODIA
(and presently member of the JICA Study Team on SWM in Phnom Penh)