All
states have laws regarding how scrap tires are to be documented,
transported, stored and disposed of. This is all in an effort eliminate
illegal tire dumps, environmental pollution save landfill space.
So
how do I make money in the tire disposal / tire recycling industry?
The
answer to this question can take many paths, and which path is right
for you and your location may not be right for the next guy.
First
the two main ways to make money from scrap tires is from the tipping
fee and from culling resellable used tires.
As
of the writing of this article I know of no recycling process for scrap
tires that on it’s own produces a net profit on the back end. Count on
your profit being produced from the tipping fees minus your processing
costs. This is the fee charged for the transport or disposal of the
scrap tires and is payed by the tire shop, government, or land owner
looking to get rid of tires. This is similar to the fee’s charged to
dispose of garbage. This fee varies greatly from one place to another
and can be by the tire or by the ton. The fees range from $0.50 - $3.00
per tire for car and light truck tires, to $3.00 - $25.00 each for semi
and off road tires. Most tire dump cleanups are charged by the ton and
range from $75.00 - $200 per ton.
Tire
culling involves picking up scrap tires from tire retailers, inspecting
them for damage and tread depth, and reselling them. There are allot of
good used tires with as much as 50% tread life left that make it into
the waste tire stream. These are often from dealer take offs, people
who get one flat tire and choose to replace all four, Ect. Most culled
tires are bulk shipped to other countries to be grooved deeper and
resold, some are also sold to used tire shops in the US. Depending on
who your selling the tire to, used tire wholesale prices can range from
$2.00 - $15.00 per tire, and $20.00 - $90.00 each retail. However if
you plan to sell tires retail most customers will demand that they are
pressure tested for leaks and ply separations, also for liability
concerns selling tires that are over 6 years old is sketchy. Be aware
though that some tire retailers will demand that their scrap tires be
destroyed and not culled.
Tire
disposal and processing business opportunities:
Become
a Tire Jockey.
No I don’t mean riding scrap tires for money. A tire jockey
is a slang term for tire hauler. For many tire processors this is how
they got started in the business. This involves getting a permit and
bond if needed from your state or local municipality to transport scrap
tires and get a truck to use on your tire pickups. Most small time tire
haulers I have dealt with us a 14 - 25ft box truck. They are payed to
pickup tires from local tire shops, then pay a local tire processor to
get rid of the tires. Their profit is made from the spread between the
two prices due mostly to volume. Say I take 20 tires to a processor
they may raise the per tire price to say a $1.50 per tire, but if I
take in a truckload of 1000 tires I can most likely negotiate a price
down to say $1.00 per tire be able to get a per ton rate. Now the tire
retailer pays you $1.50 or higher to pick up a low volume of tires and
you make $.50 per tire. So on 1000 tires you grossed $500.00. Some tire
haulers will also do some tire culling to increase there profits. Some
even store and sell them directly on Craigslist and Ebay.
Become
a scrap tire processor.
To start with you need to find out what local markets are
available for processed scrap tires, then how much you can spend on
equipment and infrastructure to get going.
The
most common methods and derived products from scrap tires are as
follows:
Baled
tires:
These
are tires that are simply packed together in a specialized tire baler
and are used for bunker sides, fill, or are shipped outside the US.
This method was a very popular for a while as other countries were
taking the bales to chop them up and burn for fuel. However in recent
years this has almost stopped completely and unless you are near a port
or have a project requiring tire bales near by, the trucking and labor
costs can be very prohibitive.
Sheared
tires:
There
are landfills that will accept tires if they are cut into quarters or
smaller. This is usually done using a specialized piece of equipment
called a tire shear. These range in price from as low as $9000.00 to as
much as $500,000 it all depends on the tire size and volume you need to
process. A good quality new shear for car and light truck tires is
going to run about $9,000 to $20,000 one for doing semi truck and
tractor tires is going to be between $20,000 to $50,000. This is by far
the most labor intensive way to get rid of waste tires, but for many of
the larger off road tires it is the only economical way.
Tire
dis-assembly:
This
can take a few different paths and also depends on if you are
processing car and light truck tires or semi truck tires. It starts by
looking at how the tire is constructed. Modern radial car and light
truck tires have steel wires in the tread section and bead seat section
of the tire only.
Where
modern radial semi truck tires have steel wire in all sections of the
tire.
Radial
tires only have wire in the bead seat.
“Semi
tire sidewalls” are on their own a saute after commodity. They are used
to weigh down highway construction barrels, signs, and silage tarps.
The value of semi sidewalls is between $.90 - $2.00 each. Bias ply
sidewalls are more valuable for use to hold down silage tarps because
they have no chance of protruding wires to tear the tarp. However bias
ply semi tires are becoming more and more rare. Many silage tarp
applications have started to use light truck tire sidewalls. The small
lightweight machines for cutting car and light truck tire sidewalls
range from $4000 to $8000 and heavy duty machines for semi truck tires
Range from $5000 to $35,000. Also add into this a tread cutter and you
have a complete way to process and get rid of scrap tires.
The
tread cutter simply cuts the tread across so it can be laid flat or cut
into multiple strips. Bias ply treads are often used for manufacturing
loading dock bumpers. Most landfills will also accept cut flattened
tire treads. The treads can also be shredded into sized chips and sold
as TDA (Tire Derived Aggregate) or TDF (Tire derived Fuel) I will cover
the TDA and TDF in the shredding section. One other option for car and
light truck tires is to also use a machine to cut out the bead seat and
shred the remaining wire free sidewall to a 3/4” chip for play ground
mulch. More on this in the Mulch section.
Rough
shredding tires:
Rough
shred is simply tires that have been run through one maybe two passes
through a tire shredder. This cuts the tire into large strips. Rough
shred is often just disposed of in a land filled. However some land
fills will take it at a reduced rate if they are approved to use it for
daily ground cover it is also sometimes used as fill in leach beds and
road beds.
TDA
and TDF:
Tire
Derived Fuel (TDF) and Tire Derived Aggregate (TDA) are essentially
tires that have been shredded into sized chips.
TDA
is typically chips in the 2 - 1” range with protruding wire no more
then 1/4” long. It is used as fill in road beds, septic tank bottoms,
leach beds, Ect.
The
use of this product is just in it’s infancy and many municipalities do
not approve of it’s use. However as many more and more gravel pits are
being shut down to to urban sprawl it is gaining in popularity.
Tire
Derived Fuel (TDF) this product varies greatly from one customer to
another. It can be sized chip ranging from 2” - 3/4”, with 1/4” long or
shorter wires protruding and some customers require it to also be wire
free. This product is used to supplement coal In power plants, cement
kilns, paper mills, Ect.
Both products TDA
and TDF require a shredder or multiple shredders with some kind of
screening system. If you you choose to produce wire free product then a
Rasper and other material separation equipment such as self cleaning
magnets and fluff separators will also be required. Tropically TDA and
TDF are sold by the ton. The price paid will vary greatly depending on
location. Most TDF sells for somewhere between $20 - $60 per ton and
TDA is usually around $10 - $20 per ton.
System for Semi Truck Tires
Rubber
Mulch:
Rubber
mulch is used as a replacement for traditional wood mulch in
applications around landscaping and is very popular for it’s shock
absorbency around playground equipment. It is also often colored
similar to wood mulch. There are four main types of rubber mulch.
The
first type introduced was made from tire tread buffings. When a truck
tire is retreaded a machine is used to shave off whats left of the old
tread to prepare it for the new tread. The chips this machine makes are
called buffings and there texture and shape look very similar to wood
mulch.
The
second type is whole tire mulch. This is just as it sounds the whole
tire is shredded and the steel rasped out. It looks like a slightly
fuzzy chip between 3/4” and 1/2” across. (see stage 1-2 off crumb
rubber machinery for explanation of equipment)
The
third type is sidewall mulch. This is a sized chip cut from car and
light truck tire sidewalls only. The side wall I first cut from the
tire then the bead ring is cut out, and lastly the leftover rubber
sidewall is chipped into 3/4” - 1/2” particles.
The last type of
rubber mulch in non tire rubber such as used conveyor belts and post
consumer scrap rubber that is chipped into 3/4- 1/2” particles.
Good
quality 99% wire free plain black rubber mulch sells for wholesale
around $250 per ton colored $350 per ton or more. If you can warehouse
and sell it retail you can easily get another 30% or more for the
product. Sidewall only and non tire rubber mulch can often be marked up
even higher because there is no chance of stray steel wires in it.
Crumb
Rubber and Rubber Powder:
Crumb
rubber is wire free, fiber free rubber granules in the 3/8” to .022” or
30 mesh.
Rubber
powder is wire free, fiber free rubber particles smaller then 30 mesh.
Crumb
rubber sells for $0.07 - $0.20 per pound. Rubber powder can sell for as
much as $.40 per pound.
Crumb
rubber is used in many different products, here are just a few:
base filler in artificial turf fields, additive in rubberized asphalt,
filler material for rubber pavers and bonded rubber products.
The
manufacturing of crumb rubber requires a substantial investment in
processing equipment and is done mostly in two different ways, knife
type processing and cryo processing.
Cryo
processing crumb rubber basically involves shredding the tires to a
manageable size. Then running it through a system that freezes the
rubber with liquid nitrogen to an extremely low temperature and
pulverizing it into crumb and powder. Then the steel, fiber, and rubber
are separated and screened. This is a simplified explanation of the
process. The equipment and facilities involved in cryo-processing are
proprietary and expensive. Also they consume massive amounts of liquid
nitrogen. However the material produced has a consistent shape that is
desirable for some industries.
Knife
type machine crumb rubber processing involves multiple reduction and
separation stages. The complexity and expense of the system and
maintenance tends to grow as the desired material size gets smaller.
Here is a list of the stages and machines in a typical crumb rubber
plant.
1:
Pre-Shredding: Take the whole tires down to a sized chip 4” or
smaller. This is usually done with a dual shaft shredder or multiple
dual shaft shredders and a screening system.
2:
Rasping: The tire chips are taken down to a 3/4” - 1/2” chip and
at the same time the steel wire is torn or rasped out of the chip. This
is done in a machine called a Rasper. A rasper is a single shaft
shredder similar in design to a granulator. It uses a heavy solid rotor
with multiple knives to cut the material against a set of stationary
bed knives. There is a screen mounted under the rotor that typically
has 3/4” - 1/2” holes. The knife gap is set so that the material is
torn instead of clean cut, this way the steel wires and some of the
fiber is ripped out of the chips.
3:
Rough separation: This process separates the steel wire, fiber, and
rubber. The wire is pulled off the mix with magnets self cleaning over
head magnets and self cleaning box magnets and conveyor head pulleys
are used. The fiber is vacuumed off and sometimes operations will
employ a screen at this point to pull out rubber particles already
reduced to the proper size.
4:
Further size reduction: The following stages will depend on the
particle size and volume per hour that needs to be made. For crumb size
ranging 1/4 inch to 1/8” this can be done easily with a open rotor
granulator. For particles less then 1/8 inch most operations use a
Crackermill. The granulator size will depend on the volume of
material being made a 30” 100hp granulator will be good for about 1 ton
per hour or 1/4” minus material. The smaller the screen size the less
the throughput. For smaller material down to 30 mesh a
crackermill works well. A 50hp crackermill can process about 1000lbs
per hour of 10-20 mesh crumb from 1/4” feed stock. This process can be
condensed into just feeding the cracker mill directly after the rough
seperation stage, but will require a much larger crackermill.
5:
Final separation: The material exiting either the granulator or
crackermill needs to be fed across a set of magnets to remove any tramp
metal fragments, and typically a zigzag air separator is used to remove
the last remaining bits of fiber. This is also sometimes done using an
up draft density separator or destoner.
6:
Final screening: Screen out the materials of different sizes and
return the overs to the further reduction stage. This is where your
product is classified into different material sizes for final packaging
or further processing.
7:
Fine grinding: This stage is only necessary if you are
manufacturing rubber powder. The 30 mesh material is fed into wet
grinding machines that mix it with water to form a slurry then grind it
to the final powder size required. It is then fed into a system to dry
and package the material. Often the powder grinding stage on it’s own
can coast as much as all of the previous steps equipment combined.
A
crumb rubber system depending on throughput and partical size will cost
between $600,000 - $1,500,000 for a system to make 1/4” to 30mesh and
$2mil plus for rubber powder. It’s not a cheap date to get into.
However many processors will start out just rough shredding and
accumulate the equipment required to get into making smaller more
valuable product.
Tire
Pyrolysis:
This is a process of thermally decomposing a tire down to
it’s raw components steel, carbon, oil, and gas. It is not as
complicated as it sounds. But the equipment needs to be designed
correctly or serious fire and explosion hazards exist. There are two
main types of tire pyrolysis systems a batch system and a continuous
feed system.
A
tire pyrolysis batch system consists of a large seal-able vessel that
can be heated to at least 800 degrees Fahrenheit and has a condenser or
fractioning tower piped into it. Essentially it is a large high
temperature still. The tires are loaded into the main vessel either
whole or shredded. The vessel door is closed and sealed. Then the
vessel is heated to a temperature high enough for the tires to break
down. The gas produced is vacuumed out of the vessel and fed into a
condenser and cooled, a large percentage will condense into oil. The
syn-gas leftover is either burned off or used to help heat the vessel.
When the unit has fully decomposed the tires, it is allowed to cool.
Once cooled down it is opened up and the leftover steel and carbon is
removed and the process starts again.
Continuous
Feed pyrolysis systems utilize a reactor vessel that has a mechanism
inside that feeds the tires through it. At each end of the reactor
there is a series of air locks this is to let material in but not allow
addition oxygen in. Tire chips and in some cases crumb rubber is fed
into the intake airlocks. It is then moved through the heated reactor
at rate that will complete the tire rubber decomposition by the time it
gets to the exit side. Then at the exit side the remaining carbon and
steel are dropped out of the exit airlocks. The gas is vacuumed out and
processed the same way as the batch system.
Unfortunately
the pyrolysis portion is the easy part. We will start by explaining the
products produced.
Tire
Pyrolysis oil: This oil has a dark brown color, similar consistency to
diesel fuel and a strong sulfur smell. It contains a large variety of
aromatic oils, solvents and a high sulfur content. It is often mixed
with diesel and sold as heating oil. It does not make very good engine
fuel because of the high sulfur and low cetane ratings. Using a
fractioning tower to distill the pyrogas yields better more sell-able
products particularly in the lighter solvent fractions. The technology
however is always changing and soon after someone my come up with a
better way to process or a better product for the pyro oil.
Sin-gas:
The syn-gas is a mix of gasses that condense bellow ambient
temperature. I’m sure with enough investment into processing equipment
the more valuable gasses could be separated. Some have used the
Fischer-Tropsch process to convert the gas into usable fuels,
lubricants and plastics. The Fischer-Tropsch process is a system that
forces the syn-gas through a catalyst, different products are made
depending on the temperature, pressure and type of catalyst used.
However most simply choose to burn it to help heat the reactor.
Carbon:
The carbon if made pure enough is a very valuable product as carbon
black. The kicker though is that if whole tires are used as feed stock
the contaminates in the carbon are not very consistent. This is due
mostly to the types of fiber used when the tires are manufactured.
There are some very successful carbon black producers that utilize
crumb rubber and non tire rubber as feed stock. The carbon from whole
tire pyrolysis is often land filled or mixed with coal and burned for
boiler fuel.
Steel
wire: The steel wire is simply sold for scrap.
As
stated before the technology is changing everyday and new uses are
found for the products produced from Tire pyrolysis.