slide1
Download
Skip this Video
Download Presentation
WELCOME

Loading in 2 Seconds...

play fullscreen
1 / 66

WELCOME - PowerPoint PPT Presentation


  • 134 Views
  • Uploaded on

SURFACE COATINGS - METAL. CUSTOMIZED ENVIRONMENTAL TRAINING. WELCOME. INSTRUCTOR. Insert Instructor Name Here. OBJECTIVES. Discuss Hazardous Materials Used in Metal Coating and Coating Removal. Define VOC and Explain How to Calculate VOC Content. Discuss the Types of Metal Coatings.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about ' WELCOME' - flynn-salas


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
slide1

SURFACE COATINGS - METAL

CUSTOMIZED ENVIRONMENTAL

TRAINING

WELCOME

slide2

INSTRUCTOR

Insert Instructor Name Here

slide3

OBJECTIVES

  • Discuss Hazardous Materials Used in Metal Coating and Coating Removal.
  • Define VOC and Explain How to Calculate VOC Content.
  • Discuss the Types of Metal Coatings.
  • Discuss Transfer Efficiency.
  • Give an Overview of Application Technology.
  • Give an Overview of Coating Removal Technology.
  • Discuss Logs and Recordkeeping.
  • Recommend Inspection Items.
  • Discuss Use of Contractors.
slide4

GOALS

  • Understand the Hazardous Materials Used in Metal Coating and Coating Removal.
  • Understand VOC and Understand How to Calculate VOC Content.
  • Be Familiar With the Types of Metal Coatings.
  • Understand How to Improve Transfer Efficiency.
  • Understand Some of the New Available Application Technologies.
  • Understand Some of the New Available Coating Removal Technologies.
  • Be Familiar With Required Logs and Records.
slide5

BACKGROUND

  • In 1998, 61,234 industries reported a total of 7.3 billion pounds of hazardous chemicals released to the air, land and water in the United States.
  • Fugitive Air Emissions, Water Emissions from Poorly Treated Rinsewater, and Solid Waste Generated from Coating and Coating Removal Operations can have a Detrimental Impact on Human Health and the Environment.
slide6

LEARNERS

  • Supervisors
  • Facility Engineers
  • Maintenance Personnel
  • Department Managers
  • Building Occupants
  • Process Specialists
  • Environmental and Safety Committees
slide7

OVERVIEW

The goal of this course is to provide supervisors with the tools needed to help reduce hazardous waste from metal surface coating operations. It recommends practical, actions that can be carried out by facility management, maintenance personnel and building occupants. It also gives an overview of new technology in coating application and removal. The course will help you to integrate good surface coating management activities into your existing organization and identify which of your staff have the necessary skills to carry out those activities.

slide8

WHAT THIS COURSE DOES NOT DO

The course is not intended to provide specific equipment recommendations for reducing pollution at your facility. These specialties required training beyond the intended scope of this course. Where this expertise is needed, outside assistance should be solicited.

federal laws
Clean Water Act addresses wastewater effluent requirements.

RCRA addresses hazardous waste used in metal finishing, including minimization

Clean Air Act Amendments address harmful air emissions in coatings

EPA’s Toxic Release Inventory (TRI) requires businesses to disclose toxic materials at facilities

FEDERAL LAWS
federal regulations
Pertinent Regulations:

40 CFR Part E413 –The Effluent Guidelines and Standards for Electroplating

40 CFR Part 59 – National Volatile Organic Compound Emission Standards for Consumer and Commercial Products

FEDERAL REGULATIONS
why finish metals
Without metal finishing, products made from metals would last only a fraction of their present life-span.

Metal finishing alters the surface of metal products.

Industries that use metal finishing in their manufacturing processes include:

Automotive

Electronics

Aerospace

Telecommunications

Hardware

Jewelry

Heavy Equipment

Appliances

WHY FINISH METALS?
the pollution problem
Of particular importance are those processes that use highly toxic or carcinogenic ingredients that are difficult to destroy or stabilize and dispose of in an environmentally sound manner.

Some of these processes are:

- Cadmium plating.

- Cyanide-based plating, especially zinc, copper, brass, bronze and silver plating.

- Chromium plating and conversion coatings based on hexavalent chromium compounds.

- Lead and lead-in plating.

- Numerous other processes.

THE POLLUTION PROBLEM
hazardous materials and processes
The metals finishing industry is concerned with pollution and wastes generated by all processes but especially those generated by the use of four specific materials in finishing processes:

the use of cadmium as a plating material,

the use of chromium as a plating material,

the use of cyanide-based electroplating solutions,

the use of copper/formaldehyde-based electroless copper solutions.

HAZARDOUS MATERIALS AND PROCESSES
cadmium
Cadmium is a common plating material that has properties superior to other metal coatings in some applications.

It displays excellent corrosion resistance and is valued for its natural lubricity or smoothness.

It exhibits good corrosion resistance, and meets the salt-spray test requirements of the automotive industry.

It can be soldered readily and is toxic to fungus and mold growth. In the past, numerous military specifications have specified the use of cadmium.

The major cadmium complex used in electroplating baths is cadmium cyanide, or Cd(CN-24).

CADMIUM
cyanide solutions
Sodium and potassium cyanide are used in electroplating bath formulations for the deposition of copper, zinc, cadmium, silver, gold, and alloys such as brass, bronze, and alballoy (copper-tin-zinc).

Electroplating baths may also utilize cyanide compounds of the metal being plated, such as copper cyanide, potassium gold cyanide, or silver cyanide.

In a well-designed wastewater treatment system, most cyanides can be destroyed through oxidation.

Cyanides used in stripping solutions, especially those for stripping nickel, are similarly resistant to oxidation and typically must be disposed of in bulk at a high cost.

CYANIDE SOLUTIONS
copper formaldehyde solutions
Electroless copper deposits are frequently used to apply a conductive base to non-conductive substrates such as plastics.

A thin copper deposit provides a base for an additional decorative or functional coating of copper, nickel, etc. One important application is in the coating of printed circuit boards.

Formaldehyde, a water pollutant and a suspected carcinogen, is used as the reducing agent in electroless copper baths. Caustic mists resulting from hydrogen evolution and air sparging in the baths present an additional hazard.

COPPER/FORMALDEHYDE SOLUTIONS
chromium
Decorative chromium plating is almost always applied over a bright nickel plated deposit, which in turn can be easily deposited on steel, aluminum, plastic, copper alloys, and zinc die castings.

Functional chromium plating is normally not applied over bright nickel plating, although in some cases, nickel or other deposits are applied first to enhance corrosion resistance.

The main ingredient in all hexavalent chromium plating solutions is chromium trioxide (CrO3).

Hexavalent chromium has been linked to cancer in humans following prolonged inhalation, and is toxic to aquatic life at relatively low concentrations.

CHROMIUM
wastewater guidelines
The Effluent Guidelines and Standards for Metal Finishing (40 CFR Part 433) are applicable to wastewater generated by any of these operations:

Electroplating

Electroless Plating

Anodizing

Coating

Chemical Etching and Milling

Printed Circuit Board Manufacturing.

Discharges from 40 additional processes, including: painting, cleaning, polishing, shearing, hot dip coating, solvent degreasing etc.

WASTEWATER GUIDELINES
wastewater guidelines1
Chemicals to be monitored include:

Cadmium

Chromium

Copper

Silver

Zinc

Cyanide

Total Toxic Organics (TTOs)

Oil and Grease

TSS

pH

WASTEWATER GUIDELINES
waste handling
Physical processes such as abrasive blasting, grinding, buffing, and polishing do not contribute as much to hazardous waste generation as chemical and electrochemical processes.

The most common hazardous waste sources are rinse water effluent and spent process baths. These systems in turn generate solid and liquid wastes that are regulated under the provisions of RCRA.

WASTE HANDLING
air emissions
The air emissions from many metal finishing processes must be controlled using scrubbing or filtering equipment.

These can generate further wastes that must also be treated, disposed, or recycled.

Some of the processing solutions used in metal finishing have a finite life, especially conversion coating solutions, acid dips, cleaners and electroless plating baths.

AIR EMISSIONS
volatile organic compounds vocs
Organic solvents, known as Volatile Organic Compounds (VOCs) are used in coatings such as paint, strippers/cleaners, etc.

In the presence of sunlight, VOCs react in a complex reaction that produces ozone. Ozone is the major ingredient in photochemical smog.

By reducing the amount of VOC in coatings, in combination with other efforts to reduce VOC emissions, you can help reduce ozone.

Most air districts restrict the amount of VOC emissions allowed.

VOLATILE ORGANIC COMPOUNDS (VOCs)
voc content
Coatings consist of solids (resin, pigments, extenders, additives) and solvents. Solvents lower the viscosity (reduce or thin), and act as the carrier for the solids. Solvents also are used to dissolve the solid resin. Solvents evaporate from the coating before, during and after application.

Solvents include VOCs, water, and exempt solvents. VOC content means pounds of VOCs per gallon of coating (lb/gal) or grams of VOCs per liter of coating (G/L), minus water and exempt solvents (exempt solvents do not contain volatile organic compounds).

VOC CONTENT
voc content1
The VOC concentration does not change if you increase the volume of mixed paint used, however, the VOC concentration does increase when adding VOC solvents such as thinners or reducers.

Manufacturers are currently being required by federal regulations to formulate paint to certain VOC specifications, that when used, according to the manufacturer’s recommendations, will meet VOC content limits. The VOC content is generally stated on the label or on the manufacturer’s paint specification sheet.

VOC CONTENT
calculating voc content
Information is from a Material Safety Data Sheet for this coating:

If the coating weighs 10.4 pounds/gallon, and it contains the following VOCs:

Xylene 2% x 10.4 lb/gal = .21 lb/gal

Toulene 2% x 10.4 lb/gal = .21 lb/gal

MEK 6% x 10.4 lb/gal = .63 lb/gal

Mixed Aliphatics 10% x 10.4 lb/gal = 1.04 lb/gal

TOTAL 20% x 10.4 lb/gal = 2.09 lb/gal

2.09 lb/gal x 119.8 (g/L) (gal/lb) = 250 grams/Liter

CALCULATING VOC CONTENT
types of coatings
Water Borne - Water is the major solvent and includes water reducible and emulsions. These coatings usually include VOCs as co-solvents.

UV Curable Coating - Liquid resin and pigment which uses UV light to cure the coating.

High Solids - Coatings that contain greater than normal resin and pigment (70 - 80% by volume).

Powder - Dry finely ground coating which is usually sprayed dry on an electrically charged surface and is later heated to its melting point so that the powder can flow together (3% VOCs by volume).

TYPES OF COATINGS
types of coatings1
Exempt Solvent based - Coatings that contain exempt solvents, primarily 1,1,1 TCA. These coatings usually include VOC as stabilizers and co-solvents.

Electrodeposition - Dip coating process where water borne coatings are electrically "plated-out".

Autodeposition - Dipcoat plating process without electrical charge.

Catalyzed Coatings - Two or three component coatings which are mixed together prior to application.

TYPES OF COATINGS
photochemically reactive
A photochemcially reactive is any solvent with an aggregate of more than 20% of its total volume composed of chemical compounds classified below:

A combination of hydrocarbons, alcohols, aldehydes, esters, ethers, or ketones having an olefinic or cycle- olefinic type of unsaturation: 5%. b. A combination of aromatic compounds with eight or more carbon atoms to the molecule except ethylbenzene: 8%. c. A combination of ethylbenzene, ketones having branched hydrocarbon structures, trichloroethylene or toluene: 20%.

PHOTOCHEMICALLY REACTIVE
transfer methods
Coatings and agents containing high VOC concentrations can be applied using the following high transfer efficiency methods:

High-Volume, Low-Pressure coating system

Electrostatic application

Flow coat application

Dip coat application

Brush coat application

Pre-packaged aerosol can application

Roll coat application

TRANSFER METHODS
spray booth filters
Spray booth filters prevent paint overspray from traveling up the exhaust vent.

Filters help increase the life span of the exhaust fans, reduce fire hazard, and provide protection from the deposition of paint particles outside the building.

It is important to maintain your booth to ensure that your operation does not cause a public nuisance and violate air regulations.

Paint overspray can travel through ineffective filters and damage the finish of automobiles and structures near your operation. Always make sure that the filters are installed properly and cover all openings. Remember that the filter media you use must be designed for your type of spray operations.

SPRAY BOOTH FILTERS
spray booth filter pressure
A pressure drop gauge may be used to determine the pressure drop across the spray booth filters.

As the filter pores become clogged, the pressure drop increases.

Filters should be replaced according to manufacturer’s recommendations.

Check your pressure gauge frequently for accuracy.

SPRAY BOOTH FILTER PRESSURE
keep your curtain wet
Waterwash booths should provide a continuous sheet of water down the face of the rear booth panel.

The water sheeting collects the overspray from the painting operation and the particulates can be skimmed from the surface of the water for disposal. If the booth does not provide a continuous sheet of water, i.e. if dry spots appear, the water spray lines should be checked for clogged openings. Remove the booth from service and repair the water lines immediately.

Never discharge your wastewater to the ground or storm drain system.

KEEP YOUR CURTAIN WET
transfer efficiency
Transfer efficiency is the percentage of paint solids deposited on the surface of your product. The cost savings in paint consumption when using high transfer efficiency guns is significant.

If you achieve 30% transfer efficiency, then 30% of the paint solids sprayed have adhered to the product, and 70% of the paint solids are on your floor, booth walls, and exhaust filters.

You can get more paint to stay on the product if you use application methods with transfer efficiencies in excess of 65%, and you buy less paint.

TRANSFER EFFICIENCY
wasting paint
High transfer efficiency saves paint and decreases emissions, thus lowering your costs.

High transfer efficiency decreases your booth filter purchases, decreases your booth cleaning expenses, and may decrease your waste disposal costs.

Train your painters to maximize their efficiency.

Consider racking parts to make overspray land on a part.

Make sure automatic spray lines spray the parts and not empty hooks.

Spray corners of parts first so overspray hits uncoated areas of the part.

WASTING PAINT
operating equipment properly
Use properly designed equipment

Eliminate cross drafts

Reduce air pressure in gun

Allow dipped parts to drain

Only spray the part

For electrostatic painting

- turn on power to electrostatic - keep a good clean ground - hook up the grounding strap

OPERATING EQUIPMENT PROPERLY
storing
Tightly seal all containers of coatings and solvents. Cans and drums should be equipped with tight fitting lids and should remain closed between uses to prevent evaporation.

Large drums should have screw caps to cover the bung holes and should be opened only to empty or fill the drum. Use a pump or funnel when filling and make sure to close the drum completely when you are finished.

Use new funnels that screw into the bung of drums and have a lid that clamps down on top of the funnel for a tight seal.

STORING
surface preparation
Preparing a surface may entail using a solvent degreaser.

Alternatives to solvent degreasing include using abrasives, water with surfactants, exempt solvents, alkaline washes, or acid etches.

Switching from solvent cleaners to other surface preparation methods can save money and reduce disposal costs.

SURFACE PREPARATION
follow mixing directions
Mixing Directions

Coating manufacturers will supply you with instructions when the coating contains more than one component.

Often the coatings must be mixed with a thinner and a catalyst.

Always mix according to the instructions.

FOLLOW MIXING DIRECTIONS
cleaning up
VOCs from your facility can be reduced significantly by cleaning your spray guns and other equipment properly.

Never clean your lines by spraying solvents into the air or into the filters.

Always direct the clean-up solvents, using minimal pressure, into containers to prevent evaporation. Remove atomization tips, soak and/or use a brush to clean the tip, then flush solvent through the gun (without the tip) into a container which is immediately sealed.

Soak spray guns in closed containers and avoid the use of VOCs for clean-up whenever possible.

CLEANING UP
slide40
Keep detailed records of the coatings applied at your facility. Monthly logs should detail the products purchased, including the name and number of the product, and the amount of product purchased, with the appropriate unit indicated (i.e., gallon, quart, pint). Remember that inspectors look for accurate records.

One proven method of record keeping involves the use of ‘job tickets’ and a summary log. Many facilities instruct the operator to record coating information for each job on a production ticket at the booth. The job tickets are then summarized nightly by the supervisor.

LOGS
application technology
Non-Cyanide Copper Plating

Non-cyanide copper plating is an electrolytic process similar to its cyanide-based counterpart.

Operating costs for the bath itself are higher for the non-cyanide process than the cyanide process.

Non-cyanide copper plating benefits:

Greatly reduces safety risks to workers.

Greatly reduces the costs and complexity of treating spent plating solutions.

Smaller risk to hydrogen cyanide exposure.

Plating solution does not have to be treated for carbonates.

APPLICATION TECHNOLOGY
application technology1
Zinc-Alloy Electroplating

Both zinc and zinc-alloy electroplating processes are very common and have a long history in the electroplating industry.

Recently these processes have been considered as possible replacements for cadmium coatings.

Benefits of zinc and zinc-alloy

Eliminates workplace exposure to cadmium and cyanide.

Corrosion resistance as good as cadmium.

Better wear resistance than cadmium.

Zinc-cobalt deposits show good resistance to atmospheres containing SO2.

APPLICATION TECHNOLOGY
application technology2
The Blackhole Technology

Uses an aqueous carbon black dispersion at room temperature for preparing through-holes in printed wire boards for subsequent copper in the through-holes.

Benefits of Blackhole Technology

Process Simplification - requires fewer process steps as well as associated chemicals and rinses.

Contamination Reduction - does not use formaldehyde.

Ease of Implementation - uses existing equipment in an electroless copper process line.

Acceptable Product Quality - accepted under MIL-P-5511OD.

Lower Operating Costs

APPLICATION TECHNOLOGY
application technology3
Ion Vapor Deposition of Aluminum (IVD)

In IVD, the coating metal is evaporated and partially ionized before being deposited on the substrate. A typical IVD system consists of a steel vacuum chamber, a pumping system, a parts holder, an evaporation source, and a high-voltage power supply.

Benefits of this technology

Health and safety risks can be greatly reduced when IVD is used in place of cadmium electroplating.

The greatest advantage of aluminum IVD is that the process significantly reduces the generation of hazardous wastes, and potentially eliminates the need for special pollution control systems.

APPLICATION TECHNOLOGY
application technology4
Physical Vapor Deposition (PVD)

A thoroughly cleaned workpiece is placed in a vacuum chamber, and a very high vacuum is drawn. The chamber is heated to between 400o and 900o F. A plasma is created from an inert gas such as argon. The workpiece is first plasma-etched to further clean the surface. The coating metal is then forced into the gas phase by either evaporation, sputtering or ion plating.

Benefits of PVD

PVD results in a thin, uniform coating that is much less likely to require machining after application.

PVD titanium nitride coatings have already gained wide acceptance in the cutting tool industry.

APPLICATION TECHNOLOGY
application technology5
Chromium-free Surface Treatments for Aluminum and Zinc  

Chromium-free surface treatments for aluminum and zinc are relatively new.

One of the few commercially proven, non-chromate surface treatments for aluminum is an inorganic conversion coating based on zirconium oxide.

A recent chrome-free post-rinse process has been developed for use on phosphated steel, zinc, and aluminum surfaces prior to painting. The new rinse, known as Gardolene VP 4683, contains neither hexavalent or trivalent chrome. It contains only inorganic metallic compounds as the active ingredient.

APPLICATION TECHNOLOGY
application technology6
Metal Spray Coating  

Molten Metal -The metal is heated by some suitable means (either resistance heating or a burner) and then supplied to the atomizing source in molten form.

Fuel/Oxidant - Oxygen/acetylene flames are typically used. The metal melts as it is continuously fed to the flame in the form of a wire or powder.

Electric arc - In this method an electric arc is maintained between two wires that are continuously fed as they melt at the arc.

These technologies for thermal spraying of metals are well developed, but they tend to have their own market niche and are not typically thought of as a replacement for electroplating.

APPLICATION TECHNOLOGY
coating removal technology
Non-Cyanide Metal Stripping

Many non-cyanide stripping solutions are typically proprietary formulations, the detailed chemistry of coating removal is not known for most solutions.

Non-cyanide metal strippers have the following benefits:

Significant potential for reducing waste treatment costs.

Often easier to recover metals from spent solutions.

Bath life is longer because higher metal concentrations can be tolerated.

COATING REMOVAL TECHNOLOGY
coating removal technology1
Plastic Media Blasting (PMB)

PMB uses low-pressure air or centrifugal wheels to project plastic media at a surface. The blast particles have sufficient impact energy, coupled with hardness and geometry to chip away or erode the coating.

Some of the major beneficial aspects of PMB include:

High stripping rate

Eliminates water use

Can selectively remove individual coating layers

Often done with recyclable thermoplastic media

Fully automated robotic systems available

Fully developed systems available

No size limitations on parts to be stripped.

COATING REMOVAL TECHNOLOGY
coating removal technology2
Wheat Starch Blasting

Wheat starch blasting uses low-pressure air to propel particles at the painted surface. The coating is stripped away by a combination of impact and abrasion. Similar equipment and techniques to PMB.

Some of the major benefits include:

Moderate stripping rates can be achieved while maintaining a gentle stripping action.

Safe on soft clad aluminum and composites

Eliminates water use

Can selectively remove individual coating layers

Uses inexpensive stripping media

Media are nontoxic and biodegradable

COATING REMOVAL TECHNOLOGY
coating removal technology3
Burnoff Coating Removal

Burnoff systems use temperatures of 370oC (700o F) or higher to volatilize and/or burn the organic coating material. Inorganic materials such as pigments remaining on the substrate must be removed by mechanical cleaning such as low-energy shot blast, manual cleaning, or water rinse.

Some of the major beneficial aspects include:

Allows rapid removal of heavy coating accumulation with a minimum of handling.

Can process parts with complex shapes.

Direct-burn ovens can removal wet, uncured coatings.

Large ovens are available to process large items, but the maximum size is limited by the oven size.

COATING REMOVAL TECHNOLOGY
coating removal technology4
Molten Salt Coating Removal

The molten salt stripping process relies on chemical oxidation of the coating by a specially formulated molten salt bath. The process uses mixtures of inorganic salts formulated to react with the coating materials.

Some of the benefits include:

Allows rapid removal of heavy coating accumulation

Provides rapid, well-controlled, uniform heating.

Wastewater stream is compatible with conventional wastewater treatment plants.

Salt baths are available to process moderate sized items, but the maximum size is limited by the bath size.

COATING REMOVAL TECHNOLOGY
coating removal technology5
Sodium Bicarbonate Wet Blasting

Compressed air moves the sodium bicarbonate medium from a pressure pot to a nozzle where the medium mixes with a stream of water. The blast medium/water mixture, accelerated to several hundred miles per hour, impacts the coated surface and shatters into a very fine particulate.

Benefits include:

High stripping rate

Can selectively remove individual coating layers

Can reduce prewashing and masking of the surface

Water dissipates the heat generated by abrasive process and reduces the amount of dust in the air.

No size limitations on the parts to be stripped.

COATING REMOVAL TECHNOLOGY
coating removal technology6
Carbon Dioxide (CO2) Pellet Cryogenic Blasting

The carbon dioxide blasting systems have a refrigerated liquid CO2 supply and a system for converting the liquid to the solid media used in coating removal. Similar to PMB.

Benefits of CO2 Pellet Cyrogenic Blasting include:

CO2 media vaporizes

Eliminates water use

Has a clean and well-defined coating removal pattern

Can selectively remove individual coating layers

Stripping cleanup requirements typically are minimal

Equipment can be stripped without requiring disassembly

COATING REMOVAL TECHNOLOGY
coating removal technology7
High Pressure Water Blasting

High-pressure waterjet stripping removes coating with a stream of water projected from specially designed nozzles at pressures of 15,000 psi to 30,000 psi or more.The coating is removed by the kinetic impact of the water stream.

Benefits of high pressure water blasting include:

The technology has a high stripping rate.

Stripping water is recycled.

Wastewater stream is compatible with conventional wastewater treatment plants.

There are no size limitations on parts to be stripped.

COATING REMOVAL TECHNOLOGY
coating removal technology8
Medium Pressure Water Blasting

Medium-pressure water blasting removes coatings with a stream of water projected from specially designed nozzles at pressures of 3,000 psi to 15,000 psi. The stripping action often is supplemented by pre-softening with an alcohol solvent or by including soft or hard abrasives in the water stream.

Some of the benefits include:

Low implementation cost using simple, robust equipment

High stripping rates

Wastewater stream is compatible with conventional wastewater treatment plants available

No size limitations on parts to be stripped

COATING REMOVAL TECHNOLOGY
coating removal technology9
Liquid Nitrogen Cryogenic Blasting

The part to be stripped is cooled by a readily available cryogenic fluid, liquid nitrogen. Nitrogen is inert, colorless, odorless, noncorrosive, and noncombustible. Liquid nitrogen is sprayed on items to be stripped as they rotate on a spindle within a stainless steel cryogenic chamber. Tensile stresses thus develop within the coating and make it brittle.

Benefits of this method include:

No ash residue

Low waste volume

Very fast cycle time (5 to 15 min)

High throughput rate

Works well on thick coating buildups.

COATING REMOVAL TECHNOLOGY
recordkeeping
Accurate recordkeeping helps to ensure that you operate in daily compliance.

Daily recordkeeping has several other advantages as well. Your records tell you how much paint you use each day. You will have an accurate record of production expenses which can enable you to cut costs.

If you have an approved Notice of Construction, it may include a limitation on annual coating usage. Do not paint more than you are allowed. Modify your production schedule to avoid penalties. Be careful with multiple shifts. If you cannot modify your daily production, contact your air district.

RECORDKEEPING
self inspections
Ifyour facility coats light duty automobiles, do the coatings used have the appropriate/compliant VOC levels?

___Yes ___No ___NA

2. Does your facility only apply coatings with less than 0.1% lead and hexavalent chromium? ___Yes ___No ___NA

3. If you coatings contain more than 2.1 Lb/Gal or 250 G/L VOC, do you only use approved application methods as outlined in your air district’s regulations (i.e. HVLP gun)?

___Yes ___No ___NA

SELF- INSPECTIONS
self inspections1
4. Does all surface coating take place in a booth or room equipped with a particulate control system capable of capturing all visible overspray? ___Yes ___No ___NA

5. Does your paint booth or room exhaust through an unobstructed vertical stack (no caps, elbows, etc.)? ___Yes ___No ___NA

6. Is your spray gun totally enclosed during clean-up, or is solvent flushed through the gun into a container which is immediately sealed? ___Yes ___No ___NA

7. Are all coating and solvent containers tightly sealed when not in use? ___Yes ___No ___NA

SELF- INSPECTIONS
self inspections2
Are all solvent containing wastes stored in tightly sealed containers until disposal? ___Yes ___No ___NA

Are solvent rags kept in tightly sealed containers when not in use? ___Yes ___No ___NA

10. Are spills of solvent containing material cleaned up upon discovery? ___Yes ___No ___NA

11. Are the most current MSDS kept for materials used, and are they available upon request? ___Yes ___No ___NA

12. Are records of purchases/usages and waste disposal kept for the previous 24 months of operations and available on site? ___Yes ___No ___NA

SELF- INSPECTIONS
self inspections3
13. Are fugitive emissions from prep work controlled?

___Yes ___No ___NA

14. Are you properly operating your pressure drop gauge (i.e., is it checked to insure that it is zeroed before the booth is turned on)? ___Yes ___No ___NA

15. Are filters seated in filter housing such that there are no gaps between the filter and the housing?

___Yes ___No ___NA

16. If you operate a water wash booth, is the water level maintained to adequately filter exhaust air?

___Yes ___No ___NA

SELF- INSPECTIONS
self inspections4
17. If you operate a water wash booth, is the water curain continuous all the way across the booth wall with no flow inconsistencies or gaps? ___Yes ___No ___NA

18. Are visible emissions and overspray NOT observed from the exhaust stack? ___Yes ___No ___NA

19. Are you performing pressure drop readings, filter changes, visual observations of filter media condition, and other manufacturer-recommended booth maintenance? ___Yes ___No ___NA

20. Are all maintenance activities recorded on a maintenance log? ___Yes ___No ___NA

SELF- INSPECTIONS
slide64

TIPS FOR USING CONTRACTORS

  • Remember, You Control Your Facility or Area!
  • Review Procedures With Them Before Starting the Job!
  • Ensure They Are Properly Trained!
  • Determine Their Environmental Compliance Record!
  • Determine Who Is in Charge of Their People!
  • Determine How They Will Affect Your Facility’s Environmental Compliance!
slide65

ELEMENTS OF A SUCCESSFUL

METAL SURFACE COATING PROGRAM

  • DETAILED WRITTEN METAL SURFACE COATING INSPECTION GUIDELINES.
  • 2. DETAILED WRITTEN METAL SURFACE COATING BEST MANAGEMENT PRACTICES.
  • 3. EXTENSIVE EMPLOYEE TRAINING PROGRAMS
  • 4. PERIODIC REINFORCEMENT OF TRAINING
  • 5. SUFFICIENT DISCIPLINE REGARDING IMPLEMENTATION
  • 6. PERIODIC FOLLOW-UP
slide66

THE IMPORTANCE OF A

CLEAN ENVIRONMENT

“I would ask all of us to remember that protecting our environment is about protecting where we live and how we live. Let us join together to protect our health, our economy, and our communities -- so all of us and our children and our grandchildren can enjoy a healthy and a prosperous life.”

Carol Browner Former EPA Administrator

ad