In Chicago, we do things our way – we commingle our construction and demolition waste only to have it in some cases sorted, separated and recycled later (see also 07/17/2009 post). I still can’t get over this thinking that separating materials at the source (the construction site) would be so much more effective.
My friend Ted Krasnesky at Pepper Construction had the following advice for me:
“…I’d recommend you visit their [the waste hauler’s] transfer station and watch it [the recycling process] in action.”
Why not? Maybe this will put my mind to rest. I pitched the idea to Kevin Loeffler at WasteBox, Inc. (the waste hauler I use). He offered to come out to my project site to look at the construction waste management set up and advise me about the various materials and their processing, and also to arrange for a visit to the transfer station (or recycling facility) he uses.
Fast forward a week: Kevin introduced me to Joseph Volini at the Heartland Recycling facility where we got to tour the recycling operation. Joseph was generous enough to let me take some photographs for this blog.
It all starts with a big pile of commingled construction and demolition waste. Yes, I was tempted to start looking for one of my Dumpster loads, but did not want to waste Kevin’s or Joseph’s time.
Once we walked around the 1000 cubic yards of debris we got to the (mostly) automated recycling facility. Let’s follow the process step by step from the beginning.
The debris is moved from the pile onto a large conveyor belt that transports it into the processing facility. Joseph indicated that a lot of recycling is happening right at this point. The key is to have a good equipment operator who has the skill to use the claws on the equipment like tweezers. Rather than dumping stuff indiscriminately on the belt, the operator carefully picks through the piles and pulls out any larger and heavier recyclables such as concrete, wood pieces, cardboard, metal, etc.
What remains is transferred onto a giant sieve (to the right in the image above), where coarse and fine materials are separated.
Anything smaller than two and a half or three inches will fall through the sieve and is transferred onto another conveyor belt (to the left in the image above).
In that process, a large magnet pulls and collects the ferrous metals such as nails, screws, pieces of metal piping, etc. and dumps them into a collection container.
The remaining fines are now largely free of ferrous metal and are deposited in a stall. Joseph explained that this material is mixed with the slush from catch basin cleanouts to solidify the material. It than is transferred to landfills where it is used as a cover material at the end of each day.
So much for the fine material. But what happened to the coarse stuff that did not fall through the sieve?
A conveyor belt transports it to what Joseph called the mezzanine, where the manual separation takes place. The belt is loaded with materials when entering the processing area (see image above), but not much is left towards the end of the mezzanine (see image below).
Along the belt are several workstations that are placed between chutes – the rectangular openings along the conveyor belt. At each station the handler scans the belt for recyclables that belong into his/her respective chute.
The first material that is pulled out is non-painted, non-contaminated wood (also referred to as “clean” wood) that is thrown onto another conveyor and transported to a wood chipper. The chips sometimes enter into the landscape trade, but are more often used as bedding for animal feed stock.
Next, cardboard and paper based waste is collected in a Dumpster under the chute…
…followed by non-ferrous metals one chute over. The more valuable scrap metal such as copper and brass is not thrown down the chute but is actually collected in bins at the mezzanine level.
Last but not least, chunks of concrete and other masonry pieces are collected. This is basically anything that can be recycled into road base or other aggregates.
If we look below the mezzanine, we find the stalls that line up with the chute openings. The red equipment to the far right is the wood chipper, followed by the containers for the cardboard and non-ferrous metals and the stall for the coarse aggregate and masonry collection.
The really sad part is at the very end of the mezzanine, where anything left that cannot be recycled or had been missed is dumped into a large trailer, destined for the landfill.
How much material is actually getting recycled in an operation like this? According to Joseph, between 65 and 70%. This number includes the fines that, after solidifying the catch basin slush, are used as a landfill cover. Joseph indicated that there is some controversy to whether this qualifies as recycling. It apparently does in the eyes of the U.S. Green Building Council, who prefers to see this material with its high waste content being used as a cover, rather than virgin soil.
Kevin (WasteBox, Inc.) explained that some Dumpster loads he hauls are directly transferred to the Heartland Recycling facility. This applies typically to single material loads, such as my plaster from the deconstruction.
Commingled loads, Kevin continued, go to his yard first, where his crews empties the Dumpster to pull all major recyclables. It is a much simpler operation because WasteBox has not the amount of real estate that Heartland Recycling has.
Kevin indicated that he diverts up to 75% of the construction and demolition debris he receives. He can sell off the salvaged cardboard, clean wood and metal scraps, which helps him to keep cost down and pass the savings on to the customer (yes, that is me!) by keeping his Dumpster rates low. Most remaining items he cannot recycle are transferred to the Heartland Recycling facility.
I am somewhat impressed by the recycling operations and the amount of content that gets diverted from the waste stream. That said, I still cannot shake the impression that separating materials at the construction site is the more efficient way and could probably result in even more waste diversion. That is, however, an item that Kevin or Joseph cannot control. They do the best they can on their end. It would be up to the construction trade and contractors to separate materials before they get to the waste hauler.
I feel privileged to have had the opportunity to visit and learn about the recycling process for my construction and demolition waste. I would like to extend a heartfelt thank you Kevin Loeffler (WasteBox, Inc.) and Joseph Volini (Heartland Recycling LLC) for their time and patience.
WasteBox, Inc. (http://www.wasteboxinc.com)
Heartland Recycling LLC (http://disposall-waste.com)