Substitution of Hazardous Chemicals in Products and Processes Workshop 4 Metal Parts Cleaning Klaus Kuhl Hamburg, June 14, 2002

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Substitution of Hazardous Chemicals in
Products and ProcessesWorkshop 4Metal Parts
CleaningKlaus Kuhl Hamburg, June 14, 2002
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Workshops 4 Metal Parts CleaningApplication

• Metal cleaning is an unavoidable step in many
  manufacturing processes
• Cleaning in the mechanical production Intermediat
  e and final cleaning after cutting, forming and
  welding
• Cleaning for surface treatment Car bodies,
  casings, galvanizing, enamelling, painting
• Cleaning for heat treatment Cog wheels,
  pistons, automobile parts
• Cleaning for maintenance and repair Car repair,
  maintenance, paint stripping

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Workshops 4 Metal Parts CleaningApplication II

• Cleaning process is the main term for the
  removal of not desired substances from surfaces
• Physically adhering substances (oil, dust,
  chips,..)
• Chemically adhering substances ( rust, scales,
  )
• Industries Construction, car repair, servicing,
  food processing, electronics, optics,
• We will focus on
• Mechanical engineering, car and steel industry
• Removal of processing fluids (drawing, cutting,
  rolling oils, lubricants)

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Workshops 4 Metal Parts CleaningTechnological
Principles
Enterprises have to choose among a vast variety
of cleaning agents, equipment and processes.
Propertiesof parts
Cleaning agent
Material composition (steel, cast, alu,
alloys,...), size, weight, geometry,narrow gaps,
tiny holes,blind holes
Amount, frequencyof parts
Cleaning equipment
Auxiliary equipment
Type and amountof dirt
Cleaning process
Further processingdegree of cleanliness
Cleaning support
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Workshops 4 Metal Parts CleaningChemical Scope
Market share of processes in Germany(D)

• Others include e.g.
• HC fp lt 55C
• Blasting
• Plasma
• Burning
• Brushing
• Source DGO, 1999
• Estimation!

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Workshops 4 Metal Parts CleaningChemical Scope
II

• Hydro carbonsAliphates, aromates, alcoholes,
  ketones, glycoles, acetates, ethers, esters,
  terpenes
• Chlorinated solventsTrichloroehylene,
  tetra(per)chloroethylene, dichloromethane
• Aqueous cleanersAlkaline, neutral, acid, usually
  containig surfactantsand additives (builders,
  sequestering agents, ..)
• Semi-aqueous cleanersCombination of surfactants
  and hydrocarbons (emulsions)

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Workshops 4 Metal Parts CleaningToxicity,
environmental impact

• Chlorinated solvents
• Poor biodegradability
• High evaporation rate, breathing in of small
  amounts may cause headaches, lung irritation,
  dizziness, poor coordination, and concentration
  difficulties during longer periods nerve,
  kidney, and liver damage.
• Skin contact for short periods may cause skin
  rashes.
• In 1995 the International Agency for Research on
  Cancers has classified TRI and PER as "probably
  carcinogenic to humans (Class 2A).
• In 2001 the classification of TRI under the EU
  Dangerous Substances Directive was changed from
  carcinogenous category 3 (R40 possible risks of
  irreversible effects) to category 2 (R45 may
  cause cancer)
• Stabilisers (zinc, alu, sodium hydroxide)
  epichlorohydrine, epoxybutane

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Workshops 4 Metal Parts CleaningToxicity,
environmental impact II
Hydrocarbons Ozone through photochemical
oxidation (summer smog) Depletion of
stratosphaeric ozone layer (some hc). Water and
soil contamination. Explosion and fire risks.
Solvents, their vapours and mists enter the body
by inhalation, by swallowing and through the
skin. The most probable exposure route depends on
the volatility and fat-solubility of the
solvent Many have a narcotic effect, causing
fatigue and dizziness. High doses may lead to
unconsciousness and death, large doses may slow
reaction time and affect rational judgement. Some
solvents irritate the eyes and the respiratory
tract. Many defat the skin, a very common cause
of skin disorders and dermatitis. They penetrate
the skin and enter the blood circulation,
damaging the liver, kidneys, heart, blood
vessels, bone marrow and the nervous system
Content of aromatics (high cleaning efficiency)
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Workshops 4 Metal Parts CleaningToxicity,
environmental impact III
Aqueous cleaners
Ingredients Function Eco Tox Human tox
Biocides Biological stability Toxic impact on organisms and microorganisms Toxic impact depending on type of biocide
Corrosion inhibitors Corrosion protection Toxic impact on organisms and microorganisms Toxic impact depending on type of corr. inhibitor
Antifoaming agents Cleaning efficiency Low biodegradability in water Skin irritation
Surfactants Cleaning activation Low biodegradability in water Skin irritation
Emulsifiers, demulsifiers Degreasing, cleaning Biodegradability in water Skin irritation
Builders Over fertilization -
Complexing agents Keep heavy metals in solution Low biodegradability in sediments -
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Workshops 4 Metal Parts CleaningPolitical Level
Chlorinated solvents Public awareness started in
the seventies (stratospheric ozone layer,
Seveso) Use is limited and regulated in many ways
(1,1,1-trichloroethane and CFC-113 banned).
Indirectly many national laws e.g. for ground
water protection, waste disposal etc. contributed
significantly to the reduction of the use of
chlorinated solvents. For metal cleaning in the
EU today only the two solvents remain TRI and
PER (methylenchloride mainly used for
paintstripping) Strictly regulated is the storage
and the maintenance of the storage
systems. European directives and regulations as
e.g. in the context of waste or disposal to water
(as e.g. Council Directives EC/86/280 or
EC/90/415) influenced the use of chlorinated
solvents Europe-wide. Additionally a number of
national regulations contributes to reductions in
the use of TRI and PER. Sweden prohibited TRI
96, exemptions possible. Germany set the emission
levels so low that chlorinated solvents can only
be used in closed loop circle machinery. France
accepts chlorinated solvents as reasons for
occupational diseases. Spain enforced national
storage, transport and emission regulations.
Permits or licences for emissions to the water
are common in the Member States. Norway has put a
tax on PER, which leads to a price increase of
app. 500
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Workshops 4 Metal Parts CleaningPolitical Level
II
Production and sales figures TRI and PER western
Europe
Metric tons in thousands
Source ECSA, Solvents Digest 20, Brussels, April
2000
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Workshops 4 Metal Parts CleaningPolitical Level
III
Hydrocarbons Restrictions regarding aromatics
content Restrictions concerning fire and
explosion risks. Occupational health regulations
(starting in DK in the eighties). OELs for widely
used typical hydrocarbons and mixtures were
enforced for the first time. Studies on how to
reduce VOCs started in several member states.
Hydrocarbons are still the dominating cleaning
agents. 1999 VOC directive (1999/13/EC) sets
emission limit values and fugitive emission
values for certain industries. It will trigger
much stricter emission control measures and by
this also support indirectly substitution. Eco
label (Nordic Svan) Government-industry
agreements Covenants (Netherlands)
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Workshops 4 Metal Parts CleaningEnterprises
Chlorinated solvents
hydrocarbons
Pro substitution Contra substitution Main actor
Cleaning efficiency Industrial users, especially producers of high quality products
More advanced expensive cleaning equipment available, to reduce emissions acc. to stricter regulations Equipment producers
More advanced expensive cleaning equipm. necessary against fire explosion Industrial users
Use of less cleaning agents through improved machinery design Industrial users, Cleaning equipment producers
Risks of spilling and soil contamination, storage obligations Industrial users, insurances, authorities
Prices for sludge (waste), contaminated with chl. solv. Industrial users, authorities
Health hazards Less potential conflicts with authorities, workers, neighbours and the public
Health hazards by stabilising additives and spontaneous risks by decomposition Industrial users, technicians and HSE
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Workshops 4 Metal Parts CleaningEnterprises II
Aqueous cleaners
Hydrocarbons
Pro substitution Contra substitution Main actor
Cleaning efficiency Industrial users (technical and quality view)
Drying problems (time, quality), corrosion Industrial users (technical and quality view)
Fire and explosion risk Industrial users
More advanced expensive waste water equipment Industrial users (economic view)
Difficult sharpening of the cleaning agent Industrial users (process handling)
Energy and water consumption Industrial users (environmental view)
Less risks of spilling and soil Industrial users (environmental view)
Less health hazards Authorities, workers, public, neighbours
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Workshops 4 Metal Parts CleaningSubstitution
Chlorinated solvents
Perchloro-ethylene(1930 to today)
1,1,1,Trichloroethane and similar chlor. solv.
(1920 to a very limited use today)
Carbontetra- chloride (CCL4) (1850 to 1940)
Trichloroethylene(1920 to today, loosing market
share towards PER)
MINOR USE AND ROUTE OF SUBSTITUTION
Chlorofluoro- carbons CFC s (1940 to 1980)
Hydrochlorofluoro-carbons (HCFCs) (1975 to today)
Hydrofluoroether HFEs and Perfluorocarbons
(PFCs) (1975 to today)
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Workshops 4 Metal Parts CleaningSubstitution II
Hydro carbons
MAJOR USE AND ROUTE OF SUBSTITUTION
SOLVENT MIXTURES with a lower VP and without
aromates (from 1990)
SOLVENT MIXTURES without aromates(from 1980)
SOLVENT MIXTURES with less impurities and without
benzene (from 1960)
CRUDE SOLVENT MIXTURES OF ALL TYPES MAINLY
ALKANES CONTAINING AROMATES
MINOR USE AND ROUTE OF SUBSTITUTION
Alcohols, Ketones, Esters, Ethers, acetates, all
other hydrocarbon based alternatives
SEMI-AEQUEOUS CLEANERS
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Workshops 4 Metal Parts CleaningSubstitution III
Aqueous cleaners
MAJOR USE AND ROUTE OF SUBSTITUTION
WATER WITH BETTER BIODEGRADABLE and LESS TOXIC
COMPONENTS(from 1985)
WATER WITH EFFECTIVE DETERGENTS(from 1975)
WATER WITH CAU-STIC SODA OR SOAP for special
purposes (from 1850)
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Workshops 4 Metal Parts CleaningSubstitution IV
Other cleaning alternatives
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Workshops 4 Metal Parts CleaningImplications
for Businesses
The large operators are switching or have already
switched to automatic and relatively closed
installations using all three types of chemicals.
All these types of cleaning agents need a
detailed control of practical handling and risk
reduction measures. These necessary
organisational efforts have been made or are
intended, if cleaning from process fluids plays
an important role for the business. Other users
in companies, where cleaning is still seen as a
minor task in the whole process, seem to tackle
the cleaning issue without a strategic
background. They use the products and
technologies, which are available on the market
and are not connected with too much regulative
restrictions. Larger strategic considerations
about substitution are rare. A general opinion
in all companies seems to be, that the regulative
restrictions and the quality demands will become
stricter. For suppliers of larger companies as
the car industry the demands from the quality or
environmental management systems of their
customers play a growing role.
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Workshops 4 Metal Parts CleaningImplications
for Businesses II
Example 1 Aluminium heat exchangers for engine
coolers and air conditioners Company considered
all possible equipment and agents and in the end
choose an airtight steam degreaser problem
lamellar distances of 0.6 mm and avoidance of
fogging effect. Drying would have taken too long
with aqueous or AII/AIII agents. Another company
selected in a similar problem steam degreasing
with a modified alcohol. Example 2 Spray can
cleaning in vehicle repair
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Workshops 4 Metal Parts CleaningConclusions
Risk discussion Discussion on chlorinated
solvents and later all types of organic solvents
resulted in a broad variety of different cleaning
technologies and cleaning chemicals. Which in
turn results in reduced transparency. Main
actors User companies, the HSE-administration,
the workers, the equipment producers and the
chemical suppliers. The role of consumers of the
final products is very weak. Choice of the user
companies still depends mainly on functionality,
but strategic choices and trade discussions about
cleaning agents have can be seen more and more.
Quality and health and environment aspects have
become more important. Risk assessment Very
difficult due to the complex influence factors.
Often shifts of risks have to be considered.
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Workshops 4 Metal Parts CleaningConclusions II
Single important factors overview
Economics Costs for investments in new cleaning
equipment hinder substitution Economics/costs
hindrance to substitution Technical
functionality Supposed less functional
effectiveness hinder substitution efforts
Technical functionality/process integration
hindrance to substitution Social
factors Increasing importance of environmental
and health aspects Social factors/communication
B2B support for substitution Risk
assessment Complex water based alternatives need
complicated risk assessments risk assessment/RA
of alternatives/shift of risks hindrance to
substitution Regulation Regulation support
substitution for large installations but not in
SMEs concerning large enterprises strong
support for substitution concerning small and
medium enterprises no influence