Journal of Applied and Industrial Sciences, 2014, 2 (2): 63-74, ISSN: 2328-4595 (PRINT), ISSN: 2328-4609 (ONLINE)

Research Article 63

Abstract-This paper gives a general view about the existing

situation of tire recycling disposal and tire maintenance activities

in many parts of the world and in Middle East particularly.

Saudi-Arabia as an important country in particular is taken as an

example with respect to international concepts in ecology

conservation. It concentrates on the auto repair activities with

regard to the generated waste tires; its volume, amount, and the

general methods of their processing and disposal in Saudi-Arabia

as the highest number of automobile fleet among the whole

Middle East countries. It gives a rough estimation of waste tires as

one of the problematic of automobile waste element that

accumulated in auto repair workshops and scattered around

areas in Saudi Arabia nowadays and in the nearest coming years

to show the hazardous situation environmentally. The latest

standard methods of waste tire processing, maintenance and

recycling by using special latest technologies. it attempts to give a

general view about the existing auto-repair workshop activities in

Tabuk Industrial Area with relation to clean production concepts.

It concentrates on the auto-repair activities wastes; its volume,

amount, and the general methods of processing and disposal of

these waste concentrated on tires as one of the most important

hazardous and problematic wastes.

The paper also gives the ideal way of tire exploitation to guarantee

maximum safety and tire time life of functioning. it suggests that

the future for many developing countries is still very risky unless

the authorized persons are aware of what is going on, concerning

automobiles wastes especially the solid parts like tires that

occupying considerable area causing fire risks and environmental

harms. It is also suggested establishment of special unit dealing

with encouraging works, studies, researches, for treatment and

recycling of auto repair workshops wastes especially waste tires.

Index Terms— Tire, Tire Hazardous, Tire Maintenance, Tire

recycling, waste tire processing

I. INTRODUCTION

Waste management is the collection, transport, processing or

disposal, managing and monitoring of waste materials in

general. Wastes relates to materials produced by human

activities beside the wastes resulted from tools and devices

which under his direct use. Waste management practices differ

from one nation to another. Developed nations in urban and

rural area, and for residential and industrial area, pay a great

attention to waste management. They form many management

institutions. Management of non-hazardous residential and

institutional waste in metropolitan areas is usually the

responsibility of local government authorities, while

management for hazardous commercial and industrial waste is

usually the responsibility of the generator the subject or

specialized local, national or international authorities. [1, 2].

Waste management concepts.

Figure1. Diagram of the waste hierarchy:

There are a number of concepts about which vary in their usage

between countries or regions. Some of the most general, widely

used concepts include:

Waste hierarchy as in Figure 1. The waste hierarchy

refers to the ‗3Rs‖ reduce, reuse and recycle, which

classify waste management strategies according to their

desirability in terms of waste minimization. The waste

hierarchy remains the cornerstone of most waste

minimization strategies. The aim of the waste hierarchy is

to extract the maximum practical benefits from products

and to generate the minimum amount of waste.

Polluter pays principle - the Polluter Pays Principle is a

principle where the polluting party pays for the impact

caused to the environment. With respect to waste

management, this generally refers to the requirement for a

waste generator to pay for appropriate disposal of the

unrecoverable material.

Tire Hazardous, Disposal and Recycling

Mohamed Gomma Elnour1 and Hala Abbas Laz*

2

1 University of Tabuk- Faculty of Engineering- the department of mechanical engineering–KSA-

E-mail: mohdgomma@yahoo.com 2 University of Tabuk- Faculty of Science- department of mathematics- KSA

(Received: February 24, 2014; Accepted: April 05, 2014)

*Corresponding author e mail: halalaz55@Gmail.com

64

Journal of Applied and Industrial Sciences, 2014, 2 (2): 63-74, ISSN: 2328-4595 (PRINT), ISSN: 2328-4609 (ONLINE)

In Saudi Arabia there is the world‘s largest Automatic

Waste Collection System, but the system is ignored

the solid wastes like auto motive wastes, heavy objects

and inorganic materials generally. Worn tires

therefore are scattered everywhere causing harm to

ecology [3,4].

Also a modern term that excessively used for ecology

conservation is clean production. Clean production is the

continuous application of an integrated preventive

environmental strategy to processes, of products and services to

increase overall efficiency, and reduce risks to humans and the

environment and reducing the quantity and toxicity of all

emissions and wastes before they leave a process [5].

A key to cleaner production is to know the flow processing of

work at any kind of production so as to be aware of material

balances in terms of input of water, energy and raw materials,

and output as production of desired products, services, and

generation of wastes (air, liquid and solid wastes). Only by

knowing the inputs, process streams and outputs, it will be

possible to efficiently manage an optimization of inputs and a

minimization of waste generation

in our rapidly developing industry and society. Traditional

end-of-pipe solution of environmental problems in all Arab

countries is no longer acceptable. It is typically more

expensive, less effective, and carries the social shame of a

reactive approach, as a treatment after the harm has been done.

Modern societies do not want environmental remediation, they

want to prevent pollution and identify waste before it is

generated. [4]Clean production initiatives should apply cleaver

methods to achieve minimum expenses. The following diagram

Figure 2 shows the input-index with relative to environmental

impact [6].

Figure 2. Input-index/Environmental impact

Cleaner production stakeholders have a strong desire for

industry to consider cleaner production opportunities in their

facilities and to follow through on their implementation. This

paper look at local and international initiatives stakeholder

community (including government, non government

organizations, consultants, industry) that contributes to the

initiation and implementation of cleaner production in

automotive service especially for tire recycling and disposal

[6,7].

Presently a vehicle plays a very important role in our lives and

living without a car can be tough especially in all Arab

countries especially in Saudi Arabia. The importance of the

vehicle doubled particularly after the amazing growth and

expansion of the cities and traveling in public transportation is

not always available and when exist its extremely unbearable.

For those who can suggested commuting in the public

transportation is unheard of necessity for time managing,

moreover the change in the ever growing all class life style, and

the rapid mode of the life force people to be in a hurry all the

time, therefore a private vehicle is the ideal solution. In the last

decade, Saudi Arabian population is doubled resulted in a huge

constructed areas and above all motorizes vehicles. On the

other hand, automobile dealers and companies adopted new

policies in selling their cars such as easy payment and car

finance systems therefore in the market buying a car became

much easier.

Nevertheless if you are driving your own car, be preparing to

face the worse when it break down, because breakdown and

failures cannot be predicted or avoided anywhere in the world.

If faced with similar crisis while traveling everywhere in Saudi

Arabia you do not have to worry since several maintenance

centers are available round the clock for timely repair. For

periodical checkup, there are many reputed centers to do so.

There are several maintenance centers, within Tabuk city and if

the default is minor, it can be rectified and repaired at any gas or

petrol station, because they are equipped with all the needed

facilities to handle such breakdown. For the periodical

check-up and major breakdown there are several workshops

within the industrial area using the different technologies, and

trained cadre to carry out this job. There are international road

between Tabuk city and other neighbouring countries. This will

persuade to encourage the investor to create best automotive

service in all the roads to cover the maintenances with best

technology to insure procedures that can be friendly with

environment. This cannot be achieved till we put into operation

the good idea to accept the approach of implementation of

cleaner production in auto repair workshop especially for

collecting, keeping and disposal of worn tires and how to

replace properly spare parts. In the initial stages the

auto-workshop may apply low and no-cost solutions element,

as attitude because of low awareness training, and poor

housekeeping and operational procedures. Generally

significant environmental benefits can often be achieved

through inexpensive solutions.

There are many efforts done in many disciplines to guarantee

efficient designing especially in mechanical designing as called

green design. Guidelines for green design, manufacturing and

recycling can be a new attitude for environmental conservation.

In reviewing the various activities among the basic concepts of

designing relationships can be summarized as guidelines, now

rapidly being accepted worldwide they are:

I. Reduce waste of materials, by refining product design,

reducing the amount of materials used in products, and

selecting manufacturing processes that minimize scrap (such as

forming instead of machining).

65

Journal of Applied and Industrial Sciences, 2014, 2 (2): 63-74, ISSN: 2328-4595 (PRINT), ISSN: 2328-4609 (ONLINE)

2. Reduce the use of hazardous materials in products and

processes.

3. Investigate manufacturing technologies that produce

environmentally friendly and safe products and by-products.

4. Develop methods of recycling, methods of waste treatment,

and methods of reuse of materials.

5. Minimize energy use, and whenever possible, encourage the

use of renewable sources of energy.

6. Encourage recycling by using materials that are parts of

either industrial or biological cycling, but not both in the same

product assembly.

7-Ensure proper handling and disposal of all waste in the case

of materials used that are not part of an industrial or biological

cycle [8].

Environmental concerns

Due to heavy metals and other pollutants in tires there is a

potential risk for the (leaching) of toxins into the groundwater

when placed in wet soils. This impact on the environment

varies according to the pH level and conditions of local water

and soil. Research has shown that very little leaching occurs

when shredded tires are used as light fill material. However,

limitations have to be put on use of tires material and each site

should be individually assessed determining if this tires product

is appropriate for given conditions.

Generally eco-toxicity may be a bigger problem than first

thought. Studies show that zinc, heavy metals, a host

of vulcanization and rubber chemicals leach into water from

tires. Shredded tire pieces leach much more, creating a bigger

concern, due to the increased surface area on the shredded

pieces. Many organisms are sensitive, and without dilution,

contaminated tire water has been shown to kill some organisms

[9].

Landfill disposal

Tires are not desired at landfills, due to their large volumes and

are quickly occupied valuable spaces. Tires can trap

methane gases, causing them to become buoyant, or bubble to

the surface. This ‗bubbling‘ effect can damage landfill liners

that have been installed to help keep landfill contaminants from

polluting.

Tire recycling

Tires are among the largest and the most problematic sources of

waste.

Tire recycling or rubber recycling is the process of

recycling vehicles' tires (or tyres) that are no longer suitable

for use on vehicles due to wear or irreparable damage (such as

punctures). These tires are among the largest and most

problematic sources of waste, due to the large volume produced

everywhere and their durability. Those same characteristics,

which make waste tires such a problem, also make them one of

the most re-used waste materials, as the rubber is very resilient

and can be reused in other products. Approximately, one tire is

discarded per person per year. Tires are also often recycled for

use on basketball courts and new shoe products. However,

material recovered from waste tires, known as "crumb," is

generally only a cheap "filler" material and is rarely used in

high volumes [10, 11].

Scrap tires and environmental issues

Once tires are discarded, they are considered scrap tires. Scrap

tires are often re-used for things from bumper car barriers to

weights to hold down tarps. Some facilities are permitted to

recycle scrap tires through chipping, and processing into new

products, or selling the material to licensed power plants for

fuel. Some tires may also be retreaded for re-use. One group did

"a study to evaluate the possibility of using scrap tires as a crash

cushion system. The objective of this study was to evaluate the

material properties of used tires and recycled tire-derived

materials for use in low-cost, reusable crash cushions".

An interesting use, developed over 30 years back but not yet

universally used, is to process scrap tires as raw material for

roads. The process is removing the metal, granulating the

rubber and then a chemical process where it is mixed with other

usual materials for macadamized roads. The resulting roads

have proved to have better waterproofing, more resilient

resulting in a smoother ride and also longer tire life. Several

countries (for example, South Korea) have regulations

requiring its use, but most do not.

Americans generate about 285 million scrap tires per

year. Many states have regulations as to the number of scrap

tires that you may have on site, due to concerns with dumping,

fire hazards, and mosquitoes. In the past, millions of tires have

been discarded into open fields. This creates a breeding ground

for mosquitoes, since the tires often hold water inside and

remain warm enough for mosquito breeding. Mosquitoes create

a nuisance and may increase the likelihood of spreading

disease. It also creates a fire danger, since such a large tire pile

is a lot of fuel. Some tire fires have burned for months, since

water does not adequately penetrate or cool the burning tires.

Tires have been known to liquefy, releasing hydrocarbons and

other contaminants to the ground and even ground water, under

extreme heat and temperatures from a fire. The black smoke

from a tire fire causes air pollution and is a hazard to downwind

properties [12].

The use of scrap tire chips for landscaping has become

controversial, due to the leaching of metals and other

contaminants from the tire pieces. Zinc is concentrated (up to

2% by weight) to levels high enough to be highly toxic to

aquatic life and plants. Of particular concern is evidence that

some of the compounds that leach from tires into water contain

hormone disruptors and cause liver lesions.

Tire life cycle

The tire life cycle according to most manufacturers is rated up

to four years, but in fact tires almost are functioning for no

more than two years. To improve tires performance and

increasing their time life they can be identified by the following

six steps

1. Product developments and innovations such as

improved compounds and camber tire shaping

increase tire life, increments of replacement,

consumer safety, and reduce tire waste.

2. Proper manufacturing and quality of delivery reduces

waste at production.

66

Journal of Applied and Industrial Sciences, 2014, 2 (2): 63-74, ISSN: 2328-4595 (PRINT), ISSN: 2328-4609 (ONLINE)

3. Direct distribution through retailers, reduces inventory

time and ensures that the life span and the safety of

the products are explained to customers.

4. Consumers' use and maintenance choices like tire

rotation affect tire wear and safety of operation.

5. Manufacturers and retailers set policies on return,

re-tread, and replacement to reduce the waste

generated from tires and assume responsibility for

taking the ‗tire to its grave‘ or to its reincarnation.

6. Recycling tires by developing strategies that combust

or process waste into new product creates viable

businesses, and fulfilling public policies [13].

Shredded tires are now being used in landfills,

replacing other construction materials, for a

lightweight backfill in gas venting systems; leach

ate collection systems, and operational liners.

Shredded tire material may also be used to cap, close,

or daily cover landfill sites. Scrap tires as a backfill

and cover material are also more cost-effective, since

tires can be shredded on-site instead of hauling in

other fill materials.

Maintenance

Tires are one of the most important -- and soft-overlooked --

components of our cars. Tires are the only things that attach our

cars to the road, and tire problems affect the car's ride comfort,

handling and safety, maintenance of tires is therefore is very

important. Forces steering, braking and accelerating between a

vehicle and the road are mediated by the tires. The tires are the

most active safety equipment of your car - your car is kept on

the road and in control of car by four contact areas the size of

your palm.

The role of the tires in the safety of a car is especially

pronounced under demanding and quickly-changing conditions

like on snow or ice, on a wet road or in surprising situations.

The demanding conditions of the north require much from tires.

The tire must retain its grip on the road even under wretched

weather conditions. Road surface friction in the wintertime

varies between the fractions coefficients 0.1 for wet ice to the

coefficient of almost one for dry roads. In addition to absolute

grip, the correct relation between lateral and longitudinal grip

ensures good anticipatory properties and steering response even

in a blizzard or watery slush.

The most important aspect of tire maintenance is proper

inflation of the tires. 75% of drivers wash their cars monthly

while only 1 out of 7 (14%) correctly checks tire pressure. The

air pressure should be checked on all tires, including the spare,

at least once a month.

Regular rotation of tires will also help prevent irregular and

premature wear. 40% of drivers have not rotated their tires

within the recommended interval of at least 8,000 miles. A

healthy habit many people follow is to rotate their tires with

every oil change.

Generally there are some simple tire safety tips to help keep the

car's occupants safe [14]

1. Checking tires pressure and to be adjusted at least once a

month. According to studies conducted by the National

Highway Traffic Safety Administration (NHTSA) on

tire-related crashes, the leading cause of tire failure is under

inflation.Underinflation can have many causes, including a

gradual loss of pressure through membranes in the tire itself. It

is typical for pressure to drop approximately 1 psi per month

and 1 psi for each 8-degree loss in ambient temperature.

Under-inflation has immediate effects on vehicle handling as

well as fuel consumption, but its potential impact on overall

safety and tire life are even greater. It results in premature and

uneven tread wear on the outer edges. Under-inflation also

increases stress on the carcass itself, through flexing and

overheating, which can lead to structural failures such as tread

separation. That's why it is imperative to check and adjust tire

pressure at least once a month and before every long trip (over

250 miles). Recommended pressures are printed on a label

located on the driver's doorframe or in the glove box.

2. Inspection of tires regularly for abnormal wear or damage

To ensure maximum tire life and safety, tires should be given a

visual inspection at least once a month and before long trips.

This is easily done at the same time when checking pressures.

The check should include

Excessive or uneven tread wear, which may indicate

improper inflation or steering and suspension misalignment;

Cracks or bulges on the sidewalls or tread;

Chunking of the tread or any indication of tread separation

from the carcass;

Signs of puncture, or nails, screws, glass, pieces of stone or

any foreign object imbedded in the tire.

If you detect any of these conditions, take the vehicle in for

further diagnosis immediately. In most cases, punctures can be

repaired if their size is not excessive.

In general, external "plugs" are not recommended. Repairs

should be made from the inside, and a complete inspection

made while the tire is off the rim. Sealing compounds and other

emergency aids should be treated only as a means of moving

the vehicle to a safe location for repair.

If abnormal tire pressure loss occurs, check the valve stems for

leakage, as well as the tire itself.

3. Rotating tires every 6,000 miles or according to owner's

manual.

Tire rotation is essential to achieve even tread wear and

maximum tread life. On front-wheel-drive cars, for example,

most of the braking, steering and driving forces are carried by

the front tires, which inevitably wear much faster. A

"cross-rotation pattern"—that is, moving the left-front tire to

the right-rear axle, the right-front tire to the left-rear axle,

etc.—can best balance tread wear and maximize tire life. That

sequence can be performed on any vehicle equipped with four

67

Journal of Applied and Industrial Sciences, 2014, 2 (2): 63-74, ISSN: 2328-4595 (PRINT), ISSN: 2328-4609 (ONLINE)

non-unidirectional tires. Designated by an arrow on the

sidewall, unidirectional tires must be rotated only front to rear

and rear to front, on the same side of the vehicle, so their

direction of revolution does not change.

All-wheel-drive and four-wheel-drive vehicles are best suited

to a lateral rotation—left to right and right to left—at the same

end of the vehicle.

4. Maintaining tires in proper balance.

Out-of-balance tires can not only cause uneven tread wear and

an uncomfortable ride but also excessive wear on the

suspension and other components. An out-of-balance tire can

be detected by a severe thumping, usually most pronounced at

highway speeds.

If such a condition occurs, have your tires dynamically

balanced as soon as possible. An experienced technician can

usually determine which tire is out-of-balance by driving the

car.

Tire balancing involves placing weights in appropriate places

on the bead or inner circumference of the wheel. Tires should

always be balanced when first installed, and whenever they are

remounted.

5. Maintaining steering and suspension in proper alignment.

Misalignment of the steering and suspension, front or rear, can

not only adversely affect the steering feel and stability of a

vehicle, but also cause rapid and uneven tire wear. If not

corrected, this misalignment can ruin a tire in a short time and

distance.

If you feel the steering "pulling" in one direction or another

when traveling straight ahead on a flat road with no crosswind,

or if you notice uneven wear on the tires, particularly front tires,

you should have the alignment checked and adjusted as soon as

possible.

Alignment should also be checked after a vehicle has been

involved in a collision or if it is used continuously on rough

roads, particularly those with large potholes.

6. Loading of a tire

Overloading is the second leading cause of tire failure, next to

under-inflation.

All tires are designed to operate within a maximum load range

designated by a code on the tire sidewall. Exceeding this can

result in both excessive wear and reduced tire life due to

structural damage, including the potential for sudden failure.

In most vehicles, the maximum passenger and cargo load for

which the vehicle and tires are designed is printed on the same

label that designates recommended tire pressures. That load,

particularly in the case of trucks and SUVs, may be

substantially less than the vehicle is physically able to

contain. It is critical that the maximum allowable load never be

exceeded.

When determining the actual load in your vehicle, don't forgot

the tongue-weight of a trailer if you are trailer towing, since it

also acts directly on the vehicle's tires.

7. Avoiding overheating tires

Heat, like load, is the enemy of tire life. The higher the heat it is

subjected to, the shorter the tire‘s life—in terms of both treads

wear and structural resistance.

High speeds, high loads, under-inflation, coarse pavement or

concrete, and aggressive driving, including high cornering

loads and hard braking, all contribute to high tire temperatures.

Combined with high ambient temperatures and continuous use,

they can create extreme circumstances and cause sudden tire

failure.

To maximize tire life and safety, therefore, it is important to

minimize the simultaneous occurrence of such conditions. Be

particularly vigilant at high temperatures and adjust your

driving style to consider its effect on tire life and performance.

8. Replacing tires when required:

The vehicle's tires should be replaced if

Any portion of the tread is worn to the "wear indicator

bars"—lateral bars molded into the tire grooves at about 20

percent of their new tread depth—or to a depth, as measured in

a groove, of 1/16th inch or less.

Tread wear is severely uneven (in which case have the wheel

alignment checked) or the center is worn much more than

the edges (be more vigilant about tire pressures).

The tire sidewalls are severely cracked or there are bulges

anywhere on the tire.

There is any indication of tread separation from the tire

carcass.

The tire has been punctured and cannot be satisfactorily

repaired.

There are other reasons you may need new tires, as well. If you

have been running on winter tires, then a change is in order in

the spring. Using snow tires on dry roads accelerates their wear

significantly and diminishes both traction and handling ability.

68

Journal of Applied and Industrial Sciences, 2014, 2 (2): 63-74, ISSN: 2328-4595 (PRINT), ISSN: 2328-4609 (ONLINE)

9. Installing tires in matched pairs or complete sets.

Installing different tires on the left and right sides can

significantly upset the handling balance of a vehicle—not to

mention its operation. For that reason, it is imperative that tires

be installed in front or rear pairs, or complete sets.

Those pairs should be the same construction, size, brand and

type, with approximately the same tread wear. In most cases, if

you have to buy one new tire, you should buy a pair. It is

essential that side-to-side pairs be the same and highly desirable

that front and rear pairs also be matched, except in cases such as

high-performance cars with larger tires in the rear.

If replacing only two, the new tires should generally go on the

rear wheels, regardless of whether the vehicle is FWD, RWD,

or AWD. It is important to maintain maximum traction at the

rear wheels to ensure stability. Putting new tires on the front

and nearly worn-out tires on the rear wheels of any vehicle is a

recipe for instability. It is thus very important to avoid dramatic

differences in tread wear, front-to-rear.

Under no circumstances should you have tires of different

construction (radial and bias ply) or different classification

(all-season and winter) on opposite ends or sides, since

handling can be adversely affected.

10. Selecting the right tires for your vehicle and driving

environment.

Recent improvements in "all-season" tires have substantially

advanced the concept of one-tire-for-all-needs. On the other

hand, more specialized tires than ever are now available for

high performance, rain, snow, ice, off-road and touring. Some

are even uni-directional, "run-flat" and even "green."

Most drivers are happy just to know they have "all-season"

tires, and that is the way most new vehicles are equipped. These

are a general compromise, sacrificing exceptional capability in

any one area of performance for acceptable capability in all.

Within that compromise, however, there are huge variations in

actual performance. Unfortunately, factors that improve one

tire characteristic tend to diminish another. For example:

A hard tread compound may enhance tread life and fuel

economy but detract from both wet and dry traction;

Short, stiff sidewall construction may enhance cornering

power and directional stability but detract from ride quality;

A wide tread with minimal grooving may enhance dry grip

but detract from traction in wet and snowy conditions;

An aggressive, open tread may enhance snow traction but

aggravate tire noise and sacrifice tread life on pavement.

In addition to dry asphalt, tires may be expected to function on

mud, snow, ice, sand or gravel, in temperatures from above

140°F to below -40°F. This will give an idea of the multiple

tradeoffs designers have to make.

Consideration should be taken that exceptional virtues are

probably achieved at the expense of others. Therefore we have

to determine what the primary needs are, and narrow the

choices accordingly. Then, if possible, drive a similar vehicle

equipped with the tires you are considering.

1) Tire Work load

The work load of a tire is monitored so that it is not put under

undue stress, which may lead to its premature failure. Work

load is measured in Ton Kilometer per hour (TKPH). The

measurement's appellation and units are the same. The recent

shortage and increasing cost of tires for heavy equipment has

made TKPH an important parameter in tire selection and

equipment maintenance for the mining industry. For this

reason, manufactures of tires for large earth-moving and

mining vehicles assign TKPH ratings to their tires based on

their size, on construction, tread type, and rubber

compound. The rating is based on the weight and speed that

the tire can handle without overheating and causing it to

deteriorate prematurely. The equivalent measure used in the

United States is Ton mile/ hour (TMPH)

Tire load capacity

Tire performance envelope diagram as showed in Figure 3 is use to

determine the following tires characteristics:

1. Determining the actual tire loads

The weight of several tractor/trailer vehicle combinations that

best represent actual maximum load conditions for these

vehicles while in operation. Mathematically determine the

mean (average) weights per axle of these weightings and divide

that value by the number of tires on that axle to determine

actual tire loading. While there are different ways to determine

tire loading for a given vehicle, actual weighting is preferable,

and will provide the best tire load information for setting

inflation pressures.

2. Determining minimum cold inflation pressures for each

tire per axle

The actual tire load should be compared to the tire load limits

on the chart for the particular tire size and ply rating. The

corresponding recommended cold inflation pressure is

indicated for the load in the chart heading. In all cases, the tire

load limit on the chart should be the same or a larger amount

than the actual determined tire load for the ply rating of the tire.

If the actual tire loads are heavier than the ply rating of the

applied tire, it may be necessary to install a tire with a higher

ply rating.

69

Journal of Applied and Industrial Sciences, 2014, 2 (2): 63-74, ISSN: 2328-4595 (PRINT), ISSN: 2328-4609 (ONLINE)

Figure 3. Tire operational speed (MPH)

3. The minimum inflation values

In all cases, the determined inflation pressures based on actual

load conditions should be considered minimum pressures.

Operational air pressure can be set higher, but in no

circumstances should they be set lower.

The inflation loading

Correct tire inflation is a key component in tire care. The

recommended maximum inflation pressures for your tires are

indicated on the certification label or in your owner's manual.

Since RVs can be loaded with many different configurations,

the load on each tire will vary. For this reason, actual air

pressure required should be determined based on the load on

each individual tire. Inflation pressure should be adjusted to

handle the tire carrying the heaviest load, and all tires on the

axle should be adjusted to this standard.

Each manufacturer provides load and inflation tables specific to

their products to help determining the correct tire inflation

pressure for the vehicle's loading.

Underinflation brings a higher risk of susceptibility to damage

due to road hazards, reduces casing durability, and causes a loss

in fuel economy, plus uneven or irregular tire wear. Severe or

prolonged underinflation brings about an increased risk of tread

separation.

It's a common practice for RV owners to lower tire pressure in

their search for a smoother ride. This is not only dangerous, it's

relatively ineffective, as the difference in ride quality is not

significant. When minimum inflation pressure requirements are

not met, tire durability and optimum operating conditions are

compromised. Tire inflation pressure should always meet at

least the minimum guidelines for vehicle weight.

II. MATERIALS AND METHODS

The materials of modern pneumatic tires are synthetic rubber,

natural rubber, fabric and wire, along with carbon black and

other chemical compounds. They consist of a tread and a body.

The tread provides traction while the body provides

containment for a quantity of compressed air. Before rubber

was developed, the first versions of tires were simply bands of

metal that fitted around wooden wheels to prevent wear and

tear. Early rubber tires were solid (not pneumatic). Today, the

majority of tires is pneumatic inflatable structure, comprising a

doughnut-shaped body of cords and wires encased in rubber

and generally filled with compressed air to form an inflatable

cushion. Pneumatic tires as shown in Figure 4 are used on

many types of vehicles, including cars, bicycle, motorcycle,

trucks, earthmovers, and aircraft. Metal tires are still used on

locomotives and railcars, and solid rubber (or other polymer)

tires are still used in various non-automotive applications, such

as some casters, carts, lawnmowers and wheelbarrow.

70

Journal of Applied and Industrial Sciences, 2014, 2 (2): 63-74, ISSN: 2328-4595 (PRINT), ISSN: 2328-4609 (ONLINE)

Figure 4. A cross-section of a tire showing ply orientations

Pneumatic tires are manufactured in about 450 tire factories

around the world. Over one billion tires are manufactured

annually, making the tire industry a major consumer of natural

rubber. It is estimated that by 2015, 1.72 billion tires are

expected to be sold globally. Tire production starts with bulk

raw materials such as rubber, carbon black, and chemicals and

produces numerous specialized components that are assembled

and cured. Many kinds of rubber are used, the most common

beings styrene-butadiene copolymer. This article describes the

components assembled to make a tire, the various materials

used, the manufacturing processes and machinery, and the

overall business model [15].

In 2004, $80 billion of tires were sold worldwide; in 2010 it

was $140 billion.

Improved tire recovery processes

To reduce waste and save money, good advice is to treat the

tires properly for maximum tire life. Simple maintenance and

correct inflation pressures mean you don't need to replace them

prematurely. A worn tire is not only dangerous, but uses more

fuel. When the time comes to change tires, considering the

Technical environmental aspects of their replacements may

also save money.

Tires account for around 3.5% of the weight of an average

vehicle. Waste prevention is a primary objective when looking

for future developments in scrap tire options. Ongoing research

into improvements in tire procurement and construction has

resulted in the life expectancy of tires continuing to lengthen.

Reuse of part-worn tires extracting the maximum safe life from

a tire saves valuable resources (oil, rubber, steel etc). Before the

tire can be resold it must be checked. Part-worn-tires must have

a minimum of 2mm tread remaining and be marked as

part-worn on both sides at the time of sale. Re-treading doubles

the life of a tire, reducing the numbers of new tires needed and

minimizing waste. Retreading involves either replacing only

the tread section or replacing rubber over the whole outer

surface of the tire. Using a retread tire for an average car takes

4.5 gallons less oil than the equivalent new tire yearly and for

commercial vehicle tires saving are estimated to be about 15

gallons per tire. Car tires can only be retreaded once, but truck

tires can be retreaded up to three times [15, 16].

The rubbers used in tire manufacturing are all thermal set

polymers. These polymers have various additives that serve a

variety of functions. The basic units of the polymer(s) used in

tires are natural rubber, synthetic polyisoprene, polybutadiene,

and, presently the most commonly used, styrene butadiene.

There are several additives that go into the monomers and/or

polymerized rubbers.

Primary activators for tire rubber are zinc oxide, satiric acid,

litharge and magnesium oxide [17, 18].

Tire fires, where tires are stored, dumped, or processed, exist in

two forms: as fast-burning events, leading to almost immediate

loss of control, and as slow-burning pyrolysis which can

continue for over a decade. They are noted for being difficult to

extinguish. Such fires produce a lot of smoke, which often

carries toxic chemicals from the breakdown of rubber

compounds while burning.

71

Journal of Applied and Industrial Sciences, 2014, 2 (2): 63-74, ISSN: 2328-4595 (PRINT), ISSN: 2328-4609 (ONLINE)

At 2012 – In Jahra, Kuwait, a five million tire fire erupted on

April 16, 2012. The fire was thought to be started deliberately

by scrap metal hawkers looking to recover scrap metal. Tires

are typically not prone to self-ignition as a tire must be heated

to at least 400 °C for a period of several minutes prior to

ignition. Therefore, tire fires are normally the result of arson or

improper manipulation with open fire. However, it is possible

for tires to spontaneously combust, especially in the case of

shredded tires or tire "crumbs" [19].

Extinguishing tire fires is difficult. The fire releases a dark,

thick smoke that contains carbon monoxide, sulfur dioxide, and

products like butadiene and styrene. A specific danger is posed

by dripping hot fluids (which may cause burns)

and valves shooting from the fire under pressure. Burning tires

are heated and as they have a low thermal conductivity, they are

difficult to cool down. Moreover, they frequently burn inside

even if they are extinguished from outside, and easily reignite

when hot. One possibility is to cover the fire with soil, reducing

the supply of oxygen and exhaust of the thick dark toxic smoke.

After extinguishing and cooling down (which may last several

days), the site must be surveyed and toxic chemicals

neutralized [14].

Despite the improved quality of retreading, there has been a

continuing decline in the passenger car retread market. While

the truck retread market remained steady. It isn't always

possible to retread tires which suffer too much damage.

Recycling through grinding is the most widespread materials

recovery process in granulated crumbs. This process produces a

range of crumb sizes through the progressive size reduction

process with the energy used to break up tires increasing as the

particle size decreases. Crumb is used in sports and play

surfaces, brake linings, landscaping mulch, carpet underlay,

absorbents for wastes and shoe soles. Crumb can also be

recycled in road asphalt. Rubberized asphalt can increase road

elasticity, temperature range and resistance to oxidation, which

can result in fewer ruts, potholes and cracks in the surface.

Some crumb can be used in formulations with virgin rubber, but

this is less than 5% of the total.

Recycling through cryogenic fragmentation, tires are shredded

and cooled to below minus 80 degrees C. A hammer mill then

pounds the chips to separate the components. The resultant

rubber granules can be used for athletics tracks, carpet

underlay, playground surfaces and rubberized asphalt for road

surfaces. The energy input required for such low temperatures

is relatively high.

Recycling through de-vulcanization, treating vulcanized rubber

with heat or chemicals can produce de-vulcanized rubber,

which can be used to replace part of the virgin material in

automotive and cycle tires, conveyor belts and footwear. The

variety of uses for this rubber has been limited due to its

uncreative nature leading to poor bonding strength. Possible

uses are for automotive components, building products,

coatings, sealants and containers for hazardous waste. The

developers believe it provides a valuable option for waste tires.

Recycling through microwave technology and Advance

Molecular Agitation Technology (AMAT) has developed a

prototype using microwave technology. This breaks the tires

into their original components. The steel is of a grade quality

and can therefore be sold for recovery. The carbon and oil are

also reusable. The amount of emissions produced is minimal. In

terms of energy recovery tires have a high calorific value, about

20% greater than that of coal, which on burning can be

harnessed to produce energy. Compared to recovery of energy

by direct burning, is a self-contained process, which avoids the

release of large volumes of combustion gases. This saves on the

cost of cleaning or "scrubbing" systems needed with normal

incineration to remove pollutants from the gases. It also means

that the process can be controlled to recover products for resale

energy recovery through incineration. In cement kilns, tires are

able to replace up to about 25% of the coal which would

otherwise be used in cement kilns and reduce nitrogen oxide

emissions [20].

Methodology

The study had been done by descriptive method and collecting

the data through visiting the Tabuk city industrial area as

example of a typical Saudi-Arabian developed city and

statistical work in some automobile fleet parks as samples for

tire running conditions. The result of this work is generally as

follows:

The samples are taken for four tire failure indices, tire pressure,

tire proper alignment, tire matching pair, tire balance.

- 23% of light automobile are underinflated, 27% are

overinflated, and 13% with improper alignment, 22%

partially or totally tires with UN matching pairs, 8%

tire misbalance.

- 33% of heavy trucks are underinflated, 8% are

overinflated, 3% with improper alignment, 2% UN

matching pairs, 11% tire misbalance.

. For auto repair workshops we have observed common

problem in their location and they were established and sited

beside accommodated civilians and their waste is polluted it,

they use to practice all kind of maintenance works that means a

lack of specific specialization beside the following

observations:

All of them are private owned, not specially designated as auto

repair workshop area but as general industrial activities. Work

is done inside or outside workshop, e.g. on footpaths or road

which is not adequate to safety. The performance of the job

sometimes done with missed special skillful technician and

technical knowledge.

Tire inflation is mainly self-service to car owner in all auto

repair workshop, this resulted to inadequate rating of inflation

due lack of good technical knowledge.

Mechanic-tire fitter uses on-site equipment without the host

employer‘s permission, without having been trained the safe

use of the equipment without a certificate of competency for the

equipment, where this is required.

Lifting equipment suitable for the task is not supplied by

employer and is not available at the breakdown scene. Service

72

Journal of Applied and Industrial Sciences, 2014, 2 (2): 63-74, ISSN: 2328-4595 (PRINT), ISSN: 2328-4609 (ONLINE)

person manually handles heavy objects, e.g. truck wheels, brake drums, etc.

There is no monitoring of the service person‘s health, safety

and welfare while away from the workshop. The service person

has no means of emergency communication with the workshop

or emergency services.

Lack of stock control leads to excess tires-parts –crowding

storage area.

Employee required working in awkward postures for long

durations inside the vehicle. Work for long periods where

awkward postures are adopted in parts of the vehicle cabin that

have restricted or constrained access, such as foot wells, under

dashboard, in boot underneath rear window.

Using air lines to clear away dust as this will release large

numbers of asbestos fibers into the breathing zones of

employees.

Using hand-operated equipment not suited to the task is used to

loosen and remove wheel nuts, e.g. short spanner or shifting

spanner is used.

Work methods are used that require awkward postures or use of

excessive force when changing tires. Final on-road tire pressure

exceeds the tire manufacturer‘s maximum operating pressure.

Firefighting equipment is not available always.

Some dealers doing repair works at streets having no even

definite fixed areas and the waste from different kinds are

thrown around the area causing a serious damage to social

health and to surrounded environmental conditions.

III. STATISTICAL ANALYSIS

The estimation of future vehicle ownership is an important

aspect of transportation planning, in particular, because the

number of trips made is directly proportional to the number of

vehicles owned. Level of vehicle ownership is one of the key

factors influencing the level of wastes generated due to

exploitation of vehicles including tires [21]. The cumulative

vehicle licenses (CVL) estimation of the number of vehicles

includes vehicles that no longer are operating on the KSA‘s

roads is very difficult for a number of reasons:

1. They may have been exported outside the KSA, and/ or

2. They have been destroyed in accidents and/or

3. They depreciated through use to the point where they are no

longer usable.

The absence of a program to write off vehicles leaving service,

due to any of these reasons, from the vehicle registration

records in the KSA requires the estimation of the number of

these inactive vehicles to reach a more likely estimation of the

total number of operating vehicles.

Generally the number of vehicle in Saudi Arabia is the biggest

fleet in the Middle East countries. According to the CVL

number of vehicle estimates about 13.0 million. The number of

fleets increases annually by more than5.4% of total fleet that

means more than 700 thousands of vehicles. According to the

General Traffic Directorate (GTD), of the Ministry of interior,

publishes the vehicle registration and accident statistics in the

KSA the total number of vehicle in the last previous years as in

Table 1 follows:

Estimating the Total Number of Vehicles Active…

Table 1. Number of registered automobiles in Saudi Arabia

year Total number of automobiles

2007 10 306 137

2008 11 411 145

2009 12 465 637

2010 13 000 039

2011 13 047 792

2012 13 872 594

Now we can obtain the regression line of the number of automobiles (let it y) on year (let it X) to estimate the total number of

automobiles in last year‘s, 2015 or 2016 [21, 22].

Using the least square method as illustrated in table (2) [23]

Table 2. The Least square method

Year X X2 Y XY

2007 -3 9 10 306 137 -30918411

2008 -2 4 11 411 145 - 22822290

2009 -1 1 12 465 637 -1 2465637

2010 1 1 13 000 539 13000539

2011 2 4 13047 792 26095584

2012 3 9 13 872 594 41617782

Total 28 84 123 844 44 507 577

73

Journal of Applied and Industrial Sciences, 2014, 2 (2): 63-74, ISSN: 2328-4595 (PRINT), ISSN: 2328-4609 (ONLINE)

XX

XYYY

2

7.14020640

n

YY

Y = 14020640.7 + 1589556.32 X (1)

Where the origin X =0 corresponds to Jan. 1 2010, and X is

measured in half years.

We can rewrite equation (1) by:

Y = 14020640.7 + 3179112.64 X (2)

Where the origin is Jan. 1 2010, and X is measured in years.

At 2016 the number of automobiles becomes: 33095316.54 ≈

33095317

Calculation of automotive recycled waste tires

Tiers: in slandered case the average to change is a set per year

(four tiers), then the number is: 132381268

From above estimation it is clear that a huge amount of

automobile waste spread all over the country and there are

millions of worn tires spread around the country.

IV. CONCLUSIONS

It can simply be summarized as follows

It was observed that availability of information on tires

hazardous as new or worn is extremely poor, with a

general absence of monitoring, information management

systems and regular reporting.

As a result of this it is impossible for competent

authorities and decision-makers to assess really the

extent of waste disposal or recycling.

Tires hazardous problems, their potential harmful

environmental impacts, and to formulate appropriate

solutions still is far from general concern of decision

maker.

The development and expansion of the existing

information management capability is central to the

elevation of the quality of decisions made on the basis of

properly collected and analyzed information.

It is noted that there was poor networking and functional

relations between government, industry, academic

institutions, Non-Governmental Organizations and

Community Based Organizations in most of Arab

countries, with little knowledge transfer or sharing of

information, dissemination of lessons learned and best

practices of waste recycling and disposal among national

stakeholders.

The Arab countries are not heavily industrialized and are

not producing any technology for waste processing

especially in tire recycling.

In some cases waste management problems are due to

outdated technology; cross boundary effects existence,

in which pollution created by tire fires hazardous in one

town may have environmental effects in another or even

for the whole country by contamination of air, ground or

surface water;

Inadequacy of legislation for workshop hazardous

waste;

Lack of trained personnel to establish, enforce, and

implement workshop hazardous waste management

standards;

Lack of trained manpower to control trans-boundary

movements of workshop hazardous waste;

Lack of information for decision-making, particularly on

workshop waste production and disposal;

Lack of understanding and experience in appropriate

technologies; that can be used in waste processing,

especially in auto repair workshop waste.

Severe lack of finances to provide human and physical

resources of workshop waste disposal

V. RECOMMENDATIONS

Tire hazardous generally and eco-efficiency in the

automotive waste recycling and disposal works are defined

and links to a series of case studies. The conceptual and

procedural approach to that demand all phases of the life

cycle of an automobile with its service process. This

should be addressed with the objective of prevention and

minimization of short and long term of risks to humans and

to the environment. To insure clear production in

automotive waste disposal and recycling an effort should

be done including the following:-

o Memorandum of understanding and contracts on

purchase of any new vehicles technologies should

have in the procurement policies means of dealing

with the after waste especially solid waste like tire.

o Facilitate technical support for cleaner production in

automotive workshop businesses to the whole Arab

countries require to profit opportunities for growth.

o Need for investment in research and development for

new technology and waste minimization options for

automotive waste especially tires waste .

o Formulating easy funding mechanisms in automotive

waste disposal processing.

o Elimination of the disposable items as far as possible

from automobile waste to limit accumulation and

hazard.

o Reduction in waste production and improvement in

waste management.

o Encouraging cost saving projects being incorporated

into an eco-cleaner production program, and

approaches as environmental management projects.

74

Journal of Applied and Industrial Sciences, 2014, 2 (2): 63-74, ISSN: 2328-4595 (PRINT), ISSN: 2328-4609 (ONLINE)

o Persuade the sustainability and continued progress of

the eco-cleaner production process in locally

industrial area of all towns.

o Promote supportive relevant legislations and

regulation in order to empowerment efficient

management of hazardous waste like tires in the

automotive tire workshop.

o Insure proper management strategy of automotive tire

workshops waste in the future in all Arab countries.

REFERENCES

[1] Herbert, Lewis "Centenary History of Waste and Waste Managers

in London and South East England". Chartered Institution of Wastes

Management, (2007).

[2] Bruce Taylor, Encouraging industry to assess and implement

cleaner production measures, Environ- Stewards Inc. Elmira, Ontario,

Canada, (2006).

[3] Environmental Protection Agency Frequently Asked Questions

about Recycling and Waste Management. Retrieved 18 October(

2006).

[4] Van de clundert,A .and Anschutz. J. ―Integrated sustainable waste

management‖ , Amestrdam, Netherlands ,(2001).

[5] Des W. Connell, Gregory J. Miller, ―Chemistry and

Ecotoxicology of Pollution‖, Publisher: Hardcover New York,

April (1984).

[6] Joseph Anthony Salvato,‖ Environmental Engineering and

Sanitation‖, McGraw-Hill. New York, USA, (1994).

[7] Ackerman, Frank.‖ Why Do We Recycle?: Markets, Values, and

Public Policy”, Island Press. ISBN 1-55963-504-5, ISBN

978-1-55963-504-2 ,(1997).

[8] Ayres, R.U. "Industrial Metabolism: Theory and Policy", In:

Allenby, B.R., and D.J. Richards, ‗‘the Greening of Industrial

Ecosystems‘‘. National Academy Press, Washington, DC, pp. 23-37.

(1994).

[9] Worldwide Technology & Business Review, 2nd ed., Juniper

Consultancy Services LTD., Uley, Gloucestershire, England, (2001).

[10] Serope Kalpakjian, Steven R. Schmid ―MANUFACTURING

ENGINEERING AND TECHNOLOGY‖. Prentice Hall, Mexico City

, Munich, Paris, Capetown, Hong Kong ,Montreal, JANUARY

(2009).

[11] CalRecovery, Inc, Environmental Factors of Waste Tire

Pyrolysis, Gasification, and Liquefaction, California Integrated Waste

Management Board, Sacramento, Calif., July (1995).

[12] C. Hermann, F.J. Schwager, and K.J. Whiting, Pyrolysis

&Gasification of Waste: A Worldwide Technology & Business

Review, 2nd ed., Juniper Consultancy ServicesLTD., Uley,

Gloucestershire, England, (2001).

[13] Liu,H., Mead, J., Stacer, R. Chelsea ―Center For Recycling And

Economic Development Environmental Impacts Of Recycling Rubber

In Light Fill Applications‖, Summary & Evaluation Of Existing

Literature University of Massachusetts .(1998).

[14] Canadian auto journalist Gerry Malloy is a regular

contributor to Sympatico / MSN Autos Canada.(2010).

[15] T. E. Baker ‖ Evaluation of the Use of Scrap Tires in

Transportation Related Applications in the State of Washington‖,

USA, (2003).

[15] C. Clark, K. Meardon, and D. Russell, ―Burning Tires for Fuel

and Tire Pyrolysis‖, Report by Pacific Environmental Services for the

U.S. Environmental Protection Agency, December,( 1991).

[16] Barbooti M.M. et al. ―Optimization of Pyrolysis Conditions of

Scrap Tires Under Inert, Gas Atmosphere‖, Journal of Analytical &

Applied Pyrolysis. Vol. 72, pp. 165-170.( 2004).

[17] Massemore B. & Zarrizski R.‖ Process for Pyrolizing Tire

Shreds & Tire Pyrolysis System‖, U.S. A. Patent 6 736 940 B2 (2004).

[18] Smith, Debra. "The great Everett tire fire, 25 years later". Everett

Herald. Retrieved 24 September 2009.

[19] Ledford C. D., ― process for conveying old rubber tires into oil &

useful resdue‖, U.S.A. patent 5095040. (1992).

[20] Divid .R.,Dennis J, and Thomas A, Statistics Concepts and

Applications, West Publishing Company, New York , USA, (1986).

[21] Murray R., Probability Administration and Statistics, Mc

GRAW-HILL BOOK COMPANY, USA, [1980].

[22] Mohamed A.E., Introduction to descriptive statistics, Khartoum

for publishing and distribution. Sudan, (2006).