No worries share any project. I really enjoy seeing other folks work.
How do you like the crusher bucket? How much concrete debris can it crush in an hour?
Thanks! The project in the picture had brick walls and that went through the crusher pretty fast. Crusher production can vary greatly with feed material, size, and desired product. The size crusher I have will only produce about 10 yd/hr. That's not much! In my opinion the design has serious drawbacks as there is NO crushing going on while one re-loads it, and the flywheels must re-spool up (to desired RPMs) with each scoop as well. If I were to do it again I would likely go with a larger crusher than the one I ended up buying. My crushing model works best when far away from any gravel pit. I did okay on the job in the picture but I did not achieve the desired margins. The recycle/reduced carbon footprint concept is also in alignment with our local political climate here.
If I were in your shoes I would start with making material for my own use then go from there the biggest trick I find is quality of material you wont get a consistent material under 3 inch minus out of a jaw you need an impact crusher.
I'm not sure of I would agree 100% with this. While I would agree that quality will vary I think feed material has as much, or more, to do with gradation than crusher type. I would also say that an impact crusher is likely the best type of crusher for recycling but not for hard rock. Primary jaw into a cone and then a screen is what most pits do with hard rock that requires gradation. If you are looking at mobile crushers, and then dumping into a screen, the screening process should get you the product quality anyway. Having a closed system is always best to make gradation. If I were only "recycle crushing" I would likely want an impact crusher with a 3 deck screen and a closed circuit. There are many ways to skin a cat and the previously described set up has a weakness to it as well. The impact crusher type can have problems with rebar and the jaw will usually allow the bar to fall out the bottom. Rebar can also wreak havoc on belts.
I would be looking to make 3 products like the competition is making as those 3 products are the most used around here. Fines for utility backfill, #57's for all sorts of uses and #24's for construction entrances and building roads in muck.
The demo company is using a Sandvik - can't tell from the road if it's a jaw or impact. I've heard that Vulcan Materials is getting geared up to recycle concrete at their quarries around the city. We might go from not having much recycled concrete to having an abundance.
Rental rates are around $20K a month for a crusher, I don't know what a screen is but figure it's less. Not being familiar with crushing rates I would want to have a stockpile of concrete on hand for testing the waters which is very doable. We have 3 large retainer walls to demo in addition to more flatwork on the arena job that might get stockpiled instead of used as fill.
I've always wanted a landfill which is a lofty goal that probably will never happen however an inert recycling facility is something within reach.
Depending upon a few things (feed material, feed size, feed operator, etc.-I feel like a broken record) I think one could reasonably expect +/- 1,000 tons a day so you may want to have a lot of crush-able material if you think you'll have a machine for a month. One might save some mobilization, set-up time, and rent if one were to employ an impact crusher with a 3-deck screen and closed circuit and see how things go. It might not be a bad idea to consult a mobile crushing outfit as well. Maybe hire them and learn from them at the same time.
You also used the term "inert" above. Please keep in mind that the EPA, and especially OHSA, have a lot of issues with concrete dust (silica) and anytime you crush to sell you are opening yourself up to MSHA regulation as well. As I'm sure you can imagine one can possibly open a can of worms if one were to make this a full-time venture.
CM1995 said:
we hardly run across any topsoil of any quantity to do anything with other than re-spread behind curbs.
Seriously doubt I could ever get any crushed concrete product to meet ALDOT specs which is the law of land in most project spec's. However structural fill, some pipe bedding, construction entrances and other "non-spec" uses are endless especially if you can be $100-200 a load cheaper than the quarry.
My goal would be to produce a clean product with no wire or other debris which I've read is a challenge.
You may be correct about spec. Even if you are able to meet specific gradation you must understand that aggregate made from recycled concrete will perform different then that of hard rock. It is more similar to sandstone and will likely break down to sand/dust if left as an exposed driving surface.
Obviously all these hurdles can be overcome. It just becomes a matter of doing some serious homework to see if it's worth the headaches, and if so, does it have the right margins.
BTW, I sourced the windshield guard from E-Plastics.