Clean, Pressure Treated, Ungrindable
HCD deals with different variances of wood and has sorted it into three categories. There are four different main products that HCD produces, they are;
- Agricultural Animal Bedding
- Biomass/Hog Fuel
- Alternative Daily Cover
- Bio filter
The majority of the wood products that HCD receives is clean wood, laminated wood and lightly painted/stained wood. The end result of the processed material must meet the agricultural leachate soil guidelines before the recycled product can be sold.
The majority of this material is processed and pre-ground in Goodwood to be sent to the Milford Processing Plant to be manufactured into Animal Bedding. The remainder of the clean wood products that are not used for Animal Bedding are then sold to Brooklyn Energy in Liverpool to be used as hog fuel to produce steam and power.
HCD also produces approximately 1,200 tonnes per year of wood that is ground to a specific sizing and then screened if necessary to provide bio filter for compost facilities such as Miller Waste and Otter Lake.
Pressure Treated Wood
Pressure treated, heavily painted and creosote wood is processed and ground to a 3" minus material and sent to Otter Lake Landfill where it is spread over top of their landfill daily. This material is also used at HCD's Three Corners C&D Landfill in Antrim for daily cover, berm building and road construction. Daily cover material must meet the Nova Scotia Landfill Leachate guidelines.
Ungrindable wood is wood that HCD receives that has heavy steel and/or other materials that are attached that is too costly to separate. Examples of this types of material would be airport hangers and older wharves, this small volume of material would get landfilled.
The drywall that arrives at HCD that is pre-sorted and the mixed loads where drywall is recoverable is processed and sent to HCD's Three Corners Landfill where there is a stationary drywall processing plant which separates the paper portion of the product from the gypsum.
The plant is a stationary slow speed shredder which feeds a trommel screen which was designed to beat the gyprock off the paper and create a ½ " minus aggregate. The aggregate is then sent to the Milford Processing Plant where the gypsum aggregate will be mixed in with our animal bedding wood. In the past, HCD has also re-sold the recycled gypsum to wallboard manufacturers to make recycled drywall.
Due to the fact that over 80% of the drywall that HCD receives is post-consumer drywall, there are often contaminants on the paper portion of the product. The contaminations can range from wallpaper, paint fiber crack filling tape and plastic corner beads. These contaminates can make it more expensive to separate the material from gypsum and as such, that material is landfilled. All clean drywall received and processed by HCD is 98% recycled while the remaining 2% is landfilled.
Asphalt Shingles / Roofing
Asphalt Shingles and Modified Bitumen Roofing
These products are received in Goodwood and either pre-processed by a slow speed shredder in Halifax or sent to the Milford Processing Facility where they are pre ground with another slow speed shredder. The pre grind removes any metals or ungrindable materials that could cause potential damage to the high speed grinder.
The high speed grinder has been specially designed to remove the aggregate portion of the shingle from the paper portion. In the same process it is transferred by conveyor to a large 40’ X 8’ two stage trommel screen. The first stage removes the loose aggregate (sand) that still contains 18-22% asphalt bitumen and the second stage removes the loose paper/fibre flake using a specific screen sizing.
The whole process is 100% recycled as the overs are reground until they are ground down to the right sizing while the metal is salvaged and sold to a local metal recycler.
The sand is used by HCD in private road building projects and also sold to local paving companies where it replaces virgin sand and a portion of the new liquid asphalt bitumen. The new asphalt with recycled sand meets all TIR specifications for asphalt use in the province. The flake is sold and sent to Lafarge Cement Plant where it replaces approximately 12% of the coal they require.
Plastics 1,2,3,4, and 5
1, 2, 4, and 5 under the SPI classification system
HCD recycles all plastics that are categorized as numbers 1, 2, 4, and 5 under the SPI classification system. These plastic materials range from film plastics, lumber wrapping, paint pails, bottles and so on. All of these plastics are separated on HCD’s sorting station or tipping area and then baled. The bales are then chipped in a shredder designed to make a ¾” minus chip and sent to Lafarge Cement Kiln as a clean burning fuel. HCD collects a sample of every load sent out and samples are tested for compliance for every one hundred tonnes sent to Lafarge. This product replaces between 6-8% of Lafarge’s coal burning usage.
concrete, bricks, stone
All aggregates accepted by HCD such as concrete, bricks, stone, etc., are recycled and reused by HCD for road construction and driveways. Aggregates that have steel imbedded in it gets crushed to recover the steel.
Ferrous and Non-Ferrous metals
HCD deals with Ferrous and Non-Ferrous metals in a variety of ways. All metals are sorted and separated on site and then sold to local metal recyclers for maximum recovery and value.
The ferrous metal is separated and mostly sent to be shredded while the non-ferrous is separated and bailed or stored in containers. The ferrous metals are mostly shipped overseas to steel mills while the non-ferrous metals are sent to Asian markets.
HCD is able to sort and recover 99% of metals from the loads that are tipped in Goodwood, HCD has several different sorting points where the metal is removed from other materials, the materials that are shred or ground up are run through magnets to remove smaller metals such as nails, screws, hinges and door handles. These metals are removed throughout the grinding of our wood products, gyproc, asphalt shingles and other materials.
siding, windows and piping
These types of plastics are mostly found in siding, windows and piping, which do not amount to a large volume of material. These plastics cannot be processed in the fuel because it creates elevated levels of toxins such as chlorine when burned. This material gets diverted to the daily cover stream and is processed along with the unmarketable wood products. There are markets for this material but the relatively low volume of the material received by HCD makes these markets infeasible.
HCD receives glass products from several private companies such as breweries and window installers which gets processed into a septic sand product or an aggregate to be mixed with the asphalt sand in cold mix asphalt. Construction glass gets diverted into our glass recycling stream if it arrives separated at the Goodwood location, if it is not separated than it will mixed in with the daily cover processing. From an occupational health and safety standpoint, there are too many hazards and dangers associated with trying to separate the construction glass from other materials.
At the present time, HCD is diverting new carpet scraps to be mixed in with the plastic shredding to be sent for fuel at Lafarge Cement Plant. Post-consumer carpet is traditionally very dirty and can be very abrasive on the chipper knives in the plastic plant. All other carpets are mixed in with the daily cover material.
All recoverable cardboard is collected, bailed and sent to a local fibre recycler to be marketed out of province.
There are often new construction loads that arrive at HCD in mixed containers, HCD will pre-sort these loads in the tipping area and then the material is moved to the sorting line. The sorting line will remove all the recoverable material and divert it to the right stream.
Demolition loads are more difficult to process and require more handling to achieve a high rate of recovery. HCD is still able to recover 90% of wood, 99% of film plastic and 95% of the metals in these loads. Mixed loads containing high percentages of insulation and styrofoam are landfilled, these loads are landfilled because these materials are difficult to handle and cause safety and health issues if the material becomes airborne.