Hints for good practice

Chemicals management
Water and waste water
Air
Waste management
IPPC

Chemicals management

Furniture industrial company

• Train the workers regularly (at least twice a year) on chemicals hazards and safe handling.
• Storage and handling of organic solvents and materials containing organic solvents:
  • use of enclosed mixing and storage vessels;
  • collect and store wood coatings and thinners in closed containers;
  • keep lids on containers closed during working operations;
  • label containers and each small pot of chemicals used at working places.
• Make visual information of chemicals hazards and hang on the working rooms walls.
• Make your chemicals register electronically.
• Evaluate the information given in Safety Data Sheet before purchasing chemical; assess environmental, health and technical aspects of chemical.
• Substitute chemicals to prevent and minimize emissions:
  • water borne coatings (low organic solvent content);
  • low-VOC coating;
  • powder coatings;
  • organic solvent free liquid coatings;
  • vegetable oil based coatings.

Printing company

• Operational procedures:
  • Clean presses immediately to minimize cleaner consumption and prevent build-up of ink.
  • Evaluate the information given in Safety Data Sheet before purchasing chemical; assess environmental, health and technical aspects of chemical.
• Inventory:
  • Purchase materials on an as-needed basis, it will further help prevent spoilage or obsolescence.
  • Make your chemicals register electronically.
• Training:
  • Train the workers regularly (at least twice a year) on chemicals hazards and safe handling. Train employees to use the least amount of cleaner possible.
  • Require SDS for all used chemicals and train employees to read them.
  • Keep SDSs in an area where employees have access to and may examine them.
• Storage and handling of organic solvents and hazardous chemicals:
  • Use of enclosed mixing and storage vessels;
  • Keep lids on containers closed during working operations;
  • Label containers and each small pot of chemicals used at working places.
• Make visual information of chemicals hazards and hang on the working rooms walls.
• Minimise the use of isopropyl alcohol:
  • Use alcohol substitutes, low- or non-alcohol solutions.
  • Use a re-circulating chiller unit that keeps fountain solution clean and reduces evaporation.
  • Check pH for consistency in each fountain solution batch (some printers find that a pH of 4-5 is effective for maintaining quality).
• Substitute inks and/or manage inks effectively to reduce emissions:
  • heat-reactive inks
  • UV-cured ink systems
  • electron-beam-dried ink systems
  • soy- and water-based inks (for non-lithographic printers)
  • inks which do not contain metals
  • keep ink containers sealed and contents leveled

Metal company

• Train the workers regularly (at least twice a year) on chemicals hazards and safe handling.
• Make visual information of chemicals hazards and hang on the working rooms walls.
• Make your chemicals register electronically.
• Evaluate the information given in Safety Data Sheet before purchasing chemical; assess environmental, health and technical aspects of chemical.
• Storage and handling of organic solvents and materials containing organic solvents:
  • Use of enclosed mixing and storage vessels;
  • Collect and store wood coatings and thinners in closed containers;
  • Keep lids on containers closed during working operations;
  • Label containers and each small pot of chemicals used at working places.
• Choice and maintenance of cooling lubricants
  • Reduce the number of different types of cooling lubricants (1 or 2 water-miscible cooling lubricants and 1 or 2 non-water-miscible cooling lubricants will meet the processing needs of most manufacturing areas) that you use will simplify your material management and allow a central cooling lubricants supply (with reduced checking and maintenance costs, particularly for water-miscible cooling lubricants).
  • Avoid of cooling lubricants containing certain materials: cooling lubricants containing chlorine should be avoided. If you currently use them they can be replaced.
  • Use of biogen cooling lubricants and ester-based cooling lubricants: these types of cooling lubricants tend to have fewer adverse affects on skin than mineral oil-based cooling lubricants. They are however more sensitive to the affects of micro-organisms so particularly careful maintenance is necessary.
  • Check cooling lubricants baths regularly, to provide early warning of the need for adjustments and maintenance. This may include the addition of water, de-mineralised water or calcium salts, to alter the hardness of the water, depending of the foaming behaviour of the cooling lubricants. Other maintenance activities include the addition of concentrate and the removal of impurities.
  • Optimise the cooling lubricants consumption: to ensure the quality of results you must monitor and adjust parameters such as cooling lubricants flow (dm3 / h) as necessary.
• Avoid certain materials in galvanising process:
  • Cyanides: for galvanising acid and cyanide-free alkaline baths are alternatives to cyanide, but they cannot be used for all applications.
  • Chrome (VI): for decorative chrome plating Chrome (III) can be an alternative although wastewater treatment is complicated. However, its range of possible applications and cost effects has not been estimated with any certainty at the moment. Alternatives for hard chrome are, currently, other metals such as electroless nickel or other coating procedures. Chrome (III) is used increasingly for passivating.

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Water and wastewater

Furniture industry

• Reduce the pollution of water:
  • replace at least most hazardous substances (CMR, PBT) with more environmentally sound substances;
  • separate flows of hazardous and non-hazardous wastewater;
  • keep the storage place of chemicals in order;
  • avoid spillages and leakages;
  • spray preservatives or coating materials on the wood using a high velocity spray system, high volume, low pressure (HVLP) spray guns  to reduce overspray, increase transfer efficiency and less drippage;
  • use concrete pads for wood treatment area and intermediate storage areas to ensure collection of drippage;
  • switch to water-based preservatives and paints, which are less toxic and damaging than typical solvent-based preservatives or paints;
  • pre-treat waste water before discharging it to surface water or municipal sewage system, i.e. use coagulation/flocculation/precipitation, sedimentation/filtration/floatation, biofilters, activated sludge/aeration lagoons etc.
• Monitor water consumption and quality optimise it, e.g. by dry equipment cleaning and vacuum systems, where feasible.
• Avoid spillages and leakage:
  • place equipment on trays, it will help to prevent chemicals or oil spillages onto the ground, into drains and into surface waters and groundwater;
  • have a cut off valve on the exit of your surface water system to a watercourse or sewer. This can then be closed if a spillage occur;
  • regularly inspect the equipment and whole system for leakages from flanges, pumps, seals, valve glands etc.;
  • use inexpensive automatic flow controllers in containers to avoid water overflow;
  • properly store the sludge from the “water curtains” systems for overspray;
• Reuse and /or recycle suitable water sources:
  • collect and use rain water;
  • recirculate cooling water;
  • reuse water in a closed circuits.

Printing industry

• Reduce the pollution of water:
  • collect spent fixing solution, reuse ir or manage as hazardous waste;
  • do not use halogenated solvents;
  • recover electrolytically silver from fixer prior to discharge of spent fixer to sewage system;
  • minimise silver in waste water: use silver-free films (vesicular, diazo and electrostatic films, photopolymer films contain carbon black as a substitute for silver); recover silver from fixing baths and have a commercial recycler pick it up; purchase a silver recovery unit and perform the recycling of fixer on premises; add ammonium thiosulfate to silver contaminated baths to extend the allowable build-up of silver.
  • use an acid stop bath prior to the fixing bath; this reduces the effect of an alkaline developer on the fixing bath pH; add acetic acid to the fixing bath, keeping the pH low to maximize soluble complexes;
  • use floating lids on bleach and developer containers to keep them fresh;
  • substitute non-hazardous raw materials for hazardous materials whenever possible;
  • employ counter current rather than parallel rinse techniques (counter current rinsing means water from previous rinsings is used in the initial film washing stage; fresh water enter the process at the final rinse stage, at which point much of the contamination is already rinsed off the film);
  • replace metal etching processes, with the associated hazardous chemical solutions and heavy metals, wherever possible (alternative plates include: presensitized lithographic, plastic or photopolymer, flexographic, electrostatic
  • use water based inks whenever possible to cut down on the use of solvent based inks that cause employee and environmental hazards;
  • clean ink fountains only when changing colours or when the ink might dry out between runs; fountains can be left with ink overnight if sprayed with special non-drying aerosol materials;
  • dedicate one press for inks with hazardous pigments or solvents;
  • use a fountain solution that contains low concentrations of isopropyl alcohol (IPA) or one containing no IPA;
  • use soap or detergent solutions for cleaning wherever possible; use solvents only for cleaning inks and oils;
  • use acetic acid based solvents, which are less toxic than other solvents;
  • use vegetable based inks and cleaning preparations;
  • organise jobs by colour, it reduces fountain cleaning;
  • use alternative methods for developing the printing forms without photochemical process, e.g  so- called computer-to-plate (CTP) method is more and more applied.   
• Monitor water consumption and quality optimise it, e.g. by dry equipment cleaning and vacuum systems, where feasible.
• Estimate the quantity of developing bath and fixing bath used per year and maintain these at acceptable levels.
• Minimise the rinse water flow in the developing machines by, for example, use of “stand-by”.
• Avoid spillages and leakage:
  • place equipment on trays, it will help to prevent chemicals or oil spillages onto the ground, into drains and into surface waters and groundwater;
  • have a cut off valve on the exit of your surface water system to a watercourse or sewer. This can then be closed if a spillage occur;
  • regularly inspect the equipment and whole system for leakages from flanges, pumps, seals, valve glands etc.;
  • use inexpensive automatic flow controllers in containers to avoid water overflow;
  • collect and properly store environment hazardous waste such as dyes, inks and solvents so that risk of spillage into the waste water system is minimised
  • use dry methods for cleanup wherever possible.
• Reuse and /or recycle suitable water sources:
  • collect and use rain water;
  • aim for the closed washing system;
  • use equipment wash down waters as makeup solutions for subsequent batches;
  • use counter current flow fixing and rinsing processes;
  • segregate wastes to increase recyclability.

Metal industry

• Reduce the pollution of water:
• spray coating materials on the wood using a high velocity spray system, high volume, low pressure (HVLP) spray guns  to reduce overspray, increase transfer efficiency and less drip page;
• use concrete pads for metal treatment area and intermediate storage areas to ensure collection of drip page;
• if technically possible, substitution of hazardous substances (e.g. cyanide, cadmium, mercury, EDTA and similar sequestering agents, nonylphenol-ethoxylates, chlorinated organics) by substances which are readily biodegradable, non-bioaccumulating and non-mutagenic and have a low toxicity;
• substitution of EDTA in degreasing baths, stripping baths and chemical nickel plating baths. Possible substitutes include e.g. citric acid, tartaric acid and gluconic acid;
• substitution of processes generating noxious substances wherever possible (e.g. cyanide oxidation with hypochlorite);
• treatment of process baths using suitable processes in order to have the longest possible service life. Such processes include, e.g. membrane filtration, ion exchange, electrolysis, thermal processes and evaporation;
• retention of bath ingredients by suitable means, such as transporting the goods in such a way that drag-out is minimised; splash guards or optimised bath composition;
• multiple use of counter-current rinse waters (at least three rinsing steps should be applied). Suitable techniques to keep more than 90% of the drag-out in a small volume for recovery/recycling are, e.g.: i) static rinse in combination with metal recovery; ii) 2-stage cascade rinsing plus closed cycle rinsing with ion exchange; iii) combined dip/spray/mist rinsing techniques. If possible these rinsing concentrates should be returned into the process baths, if necessary after specific treatment/concentration. By applying these rinsing techniques process baths can often be operated as closed water/low waste systems;
• separation of suitable non-ferrous metal waste water streams to carry out internal recycling (e.g. by electrolysis) or external recovery (e.g. by non-ferrous metal industry);
• recovery of EDTA from chemical copper plating baths (e.g. by precipitation as H₄EDTA) and their rinse baths (e.g. by precipitation after a concentration step, e.g. by anion exchange);
• replacement of chlorinated solvents by water-based systems or non-halogenated organic solvents,
• use alternative methods for metal surface treatment from oils, greases, rosin fluxes, e.g. cleaning with dry ice.  
• Monitor water consumption and quality optimise it, e.g. by dry equipment cleaning and vacuum systems, where feasible.
• Avoid spillages and leakage:
• place equipment on trays, it will help to prevent chemicals or oil spillages onto the ground, into drains and into surface waters and groundwater;
• have a cut off valve on the exit of your surface water system to a watercourse or sewer. This can then be closed if a spillage occur;
• regularly inspect the equipment and whole system for leakages from flanges, pumps, seals, valve glands etc.;
• use inexpensive automatic flow controllers in containers to avoid water overflow;
• properly store the sludge from the “water curtains” systems for overspray or electroplating baths;
• Reuse and /or recycle suitable water sources:
• collect and use rain water;
• recirculate cooling water;
• reuse water in a closed circuits.

Besides these advices, also draft EU BAT references document (BREFs) for ferrous metals processing, non-ferrous metals processing, surface treatment of metals can also provide guidance to reduce emissions to water. Although these documents are binding only for large companies (which fall under IPPC directive), also for smaller companies they can give some ideas for the improvement of own performance: see in English http://eippcb.jrc.es/pages/FActivities.htm

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Air

Furniture industry

• Properly set-up and adjust equipment, e.g. air and fluid pressure should be high enough but no higher than needed to provide good atomization.
• Less viscous coating materials are easier to atomize, and they can be atomized at lower pressures. There are two ways to control viscosity: by dilution with a solvent and by heating. Heating the coating material to the desired viscosity instead of diluting it with solvent can give comparable atomization with lower VOC emission potential.
• The spray pattern should be optimized to the work piece size, shape, and orientation. Slender pieces should be coated with a narrow pattern while a larger pattern can be used for larger pieces.
• The piece to be painted should be positioned to make spraying as comfortable as possible for the operator, and small pieces should be positioned such that overspray from one piece will fall onto another piece.
• Train the operator regularly (at least twice a year) for good finish quality and efficient material usage. Operators should be trained to use the proper spray techniques such as gun position, motion, triggering and overlap:
  • if spray gun is held too far away, a dry spray and decreased transfer efficiency may result, while the paint may run and sag if the gun is held too close to the piece;
  • to reduce uneven paint coverage, the operator should hold the gun perpendicular to the work piece as much as possible; a sweeping arm motion will usually keep the gun in the proper position;
  • proper triggering, i.e., the gun is triggered with each stroke, reduces material usage and finish defects. The stroke should be started before the trigger is pulled, and the trigger should be released before the end of the stroke;
• Equipment Maintenance:
  • spray guns need to be kept clean and lubricated daily to keep them operating properly;
  • when cleaning the gun in solvent, immerse only the tip of the gun;
  • replace worn parts since they can significantly reduce painting transfer efficiency.
• Substitute chemicals to prevent and minimize emissions:
  • water borne coatings (low organic solvent content);
  • higher solids content coatings (!resist the temptation to thin the coatings by adding solvent, better reduce viscosity by heating);
  • low-VOC coating;
  • powder coatings;
  • organic solvent free liquid coatings;
  • radiation cured coatings (for example, ultra violet and electron beam).
• Change technologies, if needed:
  • high-volume/low-pressure (HVLP) spray equipment > provides transfer efficiency as high as 40 to 65 percent compared to 20 to 40 percent for conventional air spray technology;
  • airless and air assisted airless systems > material consumption reduced; waste volume from spray booth cleanup reduced;
  • electrostatic spray systems > waste reduction from wiping stain compared to conventional spray units;
  • flat line finishing > waste reduction in VOCs;
  • UNICARB system using super-critical carbon dioxide (CO₂) in place of some organic solvents to apply coatings to wood, metal, and plastic materials > improve finish quality with fewer coating applications, no VOC;
  • UV-curable coatings can be applied using spray equipment, roll coaters, or curtain coaters;
  • replace water-based paint booth filters with dry filters > dry filter will double paint booth life and allow more efficient treatment of wastewater;
• Recover and reuse or recycle materials either on-site, off-site to reduce waste management costs and raw material purchases:
  • reuse cleaning solvent for painting lines and equipment as a reducer for the next batch of the same or darker colour;
  • flush equipment first with dirty solvent before final cleaning with virgin solvent;
  • distilling "dirty" solvent and reuse it for cleaning is another common practice;
  • recycle wet spray booth wash water by removal of paint solids;
  • recycle spent solvents with recovery units including:
    • small on-site solvent recovery still to recycle spent lacquer thinner;
    • small in-house still to recycle methylene chloride;
    • in-house still to recycle xylene
    • batch distillation unit to recover xylene from paint equipment cleaning
    • batch distillation to recover isopropyl acetate generated during equipment cleaning
    • recovery system for solvents contained in air emissions
    • solvent recovery system to recover and reuse spent methyl ethyl ketone
• Use multi-purpose materials > it may decrease employee confusion, reduces the number of rarely used products and therefore potentially reduces out-of-shelf-life waste.
• Storage and handling of organic solvents and materials containing organic solvents:
  • use of enclosed mixing and storage vessels;
  • collect and store wood coatings and thinners in closed containers;
  • keep lids on containers closed during working operations;
  • label containers.

Printing industry

• Press Cleaning:
  • wipe excess ink off before cleaning equipment with solvents;
  • substitute high VOC cleaners with low VOC cleaners containing no more than 30% VOC by weight. Use those with a lower vapour pressure and higher flash point > they are divided in to 4 groups according to their flash points:
    • < 21ºC > are not allowed to use in printing industry> very fast evaporation, vapors are harmful for health. High explosion risk.
    • 21ºC – 55ºC > flammable, high evaporation, vapours are harmful for health. Not allowed to use on new presses.
    • > 55ºC > low evaporation, vapours are harmful for health. Flammable, but the flame point is high.
    • > 100ºC > non VOC, are highly recommended to use on printing presses, e.g. vegetable based cleaning agents.
  • change from a petroleum oil-based ink to a vegetable oil-based ink such as soy or linseed oil;
  • install automatic cleaning systems reduce cleaner consumption by removing excess ink > also prevent ink build-up which requires stronger cleaning solutions;
  • try to use one type of solvent for all purposes > will improve recycling capabilities;
  • schedule jobs by colour > clean the ink tray only when changing colours or if ink might dry out between runs;
  • applying solvent directly to roller blanket with a squeeze bottle. Also squeeze used towels > reuse the liquid for initial cleanup, followed by clean solvent for final cleanup;
• Photochemicals:
  • install floating lids to exclude air and reduce evaporation and contamination > can double the life of the solution;
  • to reduce the amount of oxidation of developer solution, add glass marbles to bring the liquid level up to the brim each time the liquid is used > will extend the chemical's useful life and the life of the bath.
• Platemaking:
  • use laser plate-making with an electronic imaging system;
  • reduce drag-in of contaminants, reduce drag-out of solutions by adding dripborads and extending drip time;
  • use nonhazardous developers and finishers;
  • increase use of direct-to-plate technologies that allow preparation of plates from computer images without intermediate steps, i.e., replace the current image-making operation with a "computerized electronic prepress system" for type-setting and copy preparations.
  • Printing and Silk Screening:
  • use water-based, soybean oil, UV-curable or electron beam drying inks in
  • preference to solvent-based;
  • dedicating presses for various ink colours, if feasible;
  • filling ink fountains with only enough ink for the run or shift and returning unemulsified links to their containers;
  • use fountain solutions that do not contain isopropyl alcohol (IPA) or have low concentrations of IPA in the dampening solution by adding small volumes of alternative chemicals such as glycols or glycol ethers;
  • adding leftover coloured inks to black ink;
  • reformulating the composition of the fountain or the solution used to eliminate isopropyl alcohol;
  • using non-toxic inks, free of heavy metals (lead, barium, cadmium and chromium;
• Finishing:
  • use water-based adhesives rather than solvent-based;
  • minimize coatings and adhesives that hinder recycling;
  • use mechanical binding methods instead of glues or adhesives.
• Recover and reuse or recycle materials either on-site, off-site to reduce waste management costs and raw material purchases:
  • flush equipment first with dirty solvent before final cleaning with virgin solvent;
  • distilling "dirty" solvent and reuse it for cleaning is another common practice;
  • recycle empty containers by purchasing ink in bulk containers that are returned to the supplier for refilling;
  • recover waste solvents on-site with batch distillation if quantities warrant, or utilize professional solvent recyclers;
  • install solvent hoods to recapture solvent losses from presses;
  • recycle used and leftover inks;
  • for silkscreen operations, recapture printing ink by squeezing screen prior to washing
• Use multi-purpose materials > it may decrease employee confusion, reduces the number of rarely-used products and therefore potentially reduces out-of-shelf-life waste.
• Storage and handling of organic solvents and materials containing organic solvents:
  • segregate spent solvent according to colour and type of ink. Reuse the collected wastes to thin future batches of the same ink;
  • use of enclosed mixing and storage vessels;
  • collect and store in closed containers;
  • keep lids on containers closed during working operations;
  • label containers.

There is also a draft BREF (BAT reference document) developed relevant for the printing. Although this  document is binding only for large companies (which fall under IPPC directive), also for smaller companies this document can give some ideas for the improvement of own performance: see in English http://eippcb.jrc.es/pages/FActivities.htm)

Metal industry

Metal processing has wide range of processes; this chapter is mainly focussing on surface cleaning and finishing.  

• Emissions during welding of plates cleaned with esters > no additional air pollution from the use of vegetable oil esters as cleaning agents > volatile organic solvents can be replaced by esters in approximately 50% of the cleaning activities;
• Properly set-up and adjust equipment, e.g. air and fluid pressure should be high enough but no higher than needed to provide good atomization.
• Less viscous coating materials are easier to atomize, and they can be atomized at lower pressures. There are two ways to control viscosity: by dilution with a solvent and by heating. Heating the coating material to the desired viscosity instead of diluting it with solvent can give comparable atomization with lower VOC emission potential.
• The spray pattern should be optimized to the work piece size, shape, and orientation. Slender pieces should be coated with a narrow pattern while a larger pattern can be used for larger pieces.
• The piece to be painted should be positioned to make spraying as comfortable as possible for the operator, and small pieces should be positioned such that overspray from one piece will fall onto another piece.
• Train the operator regularly (at least twice a year) for good finish quality and efficient material usage. Operators should be trained to use the proper spray techniques such as gun position, motion, triggering and overlap:
  • if spray gun is held too far away, a dry spray and decreased transfer efficiency may result, while the paint may run and sag if the gun is held too close to the piece;
  • to reduce uneven paint coverage, the operator should hold the gun perpendicular to the work piece as much as possible; a sweeping arm motion will usually keep the gun in the proper position;
  • proper triggering, i.e., the gun is triggered with each stroke, reduces material usage and finish defects. The stroke should be started before the trigger is pulled, and the trigger should be released before the end of the stroke;
• Equipment Maintenance:
  • spray guns need to be kept clean and lubricated daily to keep them operating properly;
  • when cleaning the gun in solvent, immerse only the tip of the gun;
  • replace worn parts since they can significantly reduce painting transfer efficiency.
• Ensure your stoving oven is operating efficiently:
  • use the correct temperature and stoving time by installing infrared driers prior to the oven;
  • fit and check an audible or visual alarm to prevent overheating;
  • reduce air extraction rates once flammable gases have been driven off;
• Substitute chemicals to prevent and minimize emissions:
  • use cleaners and coating with low toxic air pollutant and VOC content > e.g. water borne;
  • for chromium electroplaters, switch from hexavalent chromium solutions, which can cause cancer, to trivalent chromium ones, which do not;
  • replace cyanide in plating solutions with less toxic compounds like zinc chloride and pyro-phosphate copper.
  • reduce the chemical concentration of the plating bath without compromising quality;
  • water borne coatings (low organic solvent content);
  • higher solids content coatings (!resist the temptation to thin the coatings by adding solvent, better reduce viscosity by heating);
  • low-VOC coating;
  • powder coatings;
  • organic solvent free liquid coatings;
  • radiation cured coatings (for example, ultra violet and electron beam).
  • anti-corrosion oil used for spraying products while packing them can be substituted by an oxidation packaging paper to put in the boxes at product delivery > the unhealthy mist that was earlier spread when preparing deliveries with the oil was fully eliminated.
• Change technologies, if needed:
  • use alternative metal deposition technologies to reduce or eliminate toxic air pollutant emissions;
  • use mechanical scraping instead of a chemical solution to remove build-up on the part;
  • replace solvent pre-cleaning operations with aqueous ultrasonic cleaning;
  • some systems use a batch multi-stage cabinet spray unit - rather like a large dishwasher > to clean parts using a neutral or alkaline solution, followed by phosphating and rinsing. The need for VOC based degreasers is therefore eliminated
  • minimize drag-out > lower bath chemical concentrations > proper part racking based on part shapes > reducing part rack removal speed > fog or spray rinsing over bath or capture it before rinsing and return it to the plating bath by using: drip boards; air knives; hang bars; drip tanks;
  • high-volume/low-pressure (HVLP) spray equipment > provides transfer efficiency as high as 40 to 65 percent compared to 20 to 40 percent for conventional air spray technology;
  • the use of coating powders instead of paint > reduces solvent emissions to almost zero, but increases the heat requirement for curing
  • airless and air assisted airless systems > material consumption reduced; waste volume from spray booth cleanup reduced;
  • electrostatic spray systems > waste reduction from wiping stain compared to conventional spray units;
  • flat line finishing > waste reduction in VOCs;
  • UNICARB system using super-critical carbon dioxide (CO₂) in place of some organic solvents to apply coatings to wood, metal, and plastic materials > improve finish quality with fewer coating applications, no VOC;
  • UV-curable coatings can be applied using spray equipment, roll coaters, or curtain coaters;
  • replace water-based paint booth filters with dry filters > dry filter will double paint booth life and allow more efficient treatment of wastewater;
  • a process using vacuum heat treatment substituted a process treating saw blades at high temperature in a bath of barium salts > stopping emissions to the air
• Recover and reuse or recycle materials either on-site, off-site to reduce waste management costs and raw material purchases:
  • reuse cleaning solvent for painting lines and equipment as a reducer for the next batch of the same or darker colour;
  • flush equipment first with dirty solvent before final cleaning with virgin solvent;
  • distilling "dirty" solvent and reuse it for cleaning is another common practice;
  • recycle wet spray booth wash water by removal of paint solids;
  • recycle spent solvents with recovery units including:
    • small on-site solvent recovery still to recycle spent lacquer thinner;
    • small in-house still to recycle methylene chloride;
    • in-house still to recycle xylene
    • batch distillation unit to recover xylene from paint equipment cleaning
    • batch distillation to recover isopropyl acetate generated during equipment cleaning
    • recovery system for solvents contained in air emissions
    • solvent recovery system to recover and reuse spent methyl ethyl ketone
• Use multi-purpose materials > it may decrease employee confusion, reduces the number of rarely-used products and therefore potentially reduces out-of-shelf-life waste.
• Storage and handling of organic solvents and materials containing organic solvents:
  • maintain a high standard of housekeeping
  • use of enclosed mixing and storage vessels > may be achieved by the use of closed mobile containers, containers with close-fitting lids, or, preferably, closed containers with pipeline delivery;
  • during hot- dip galvanizing hygroscopic materials are unlikely to give rise to dust. Ashes from the zinc bath need to be kept dry to avoid the risk of toxic arsine gas (arsenic trihydride) being formed.
  • collect and store metal surface coatings and thinners in closed containers;
  • potentially dusty materials should be stored in covered containers or undercover keep lids on containers closed during working operations;
  • spillages should be cleared as soon as possible and in the case of solid materials this should be achieved by the use of vacuum cleaning, wet methods, or other appropriate techniques. Dry sweeping of dusty spillages should not be permitted
  • label containers.

Besides these advices, also draft EU BAT references document (BREFs)  for surface treatment using organic solvents provides guidance to reduce air emissions of VOC. Although this document is binding only for large companies (which fall under IPPC directive), also for smaller companies this document can give some ideas for the improvement of own performance: see in English http://eippcb.jrc.es/pages/FActivities.htm

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Waste management

Furniture industry

• The following sections list some of the waste minimisation measures that could be introduced in different processes in a typical furniture manufacturing operation.
• Raw Materials
  • Check containers and consignments of goods-in for transit damage.
  • Check the quality of goods-in – especially timber – before buying to avoid excessive waste.
  • Check the exact quantity of goods-in to be able to calculate the exact relation with respective waste output.
  • Communicate to your suppliers on your requirements before buying any raw materials and make these clear in the contract.
  • Follow FIFO (first in first out) stock rotation to help preventing wastage due to "out-of-date" or "no-longer-used" products.
  • Insist on general cleanliness and using good working techniques in storage areas to guarantee careful attitude and prevent spillages / spoilage.
  • Order the right size of the goods! Over-ordering results in tying up capital and space. On the other hand, under-ordering of container size can greatly increase the amount of man-hours required to handle goods. Also, e.g. big drums for wood coatings are usually also taken back by supplier, while small ones are not.
  • Ensure that drivers are properly trained, storage areas suitably designed and proper safety equipment used for using fork-lift trucks to prevent damage to raw material stocks.
  • Store veneer at the correct humidity and temperature to avoid the problems of splitting.
• Packaging on Goods-In
  • Evaluate the potential for segregation, reuse and recovery of all packaging. If it is only suitable for disposal, consult the supplier and try to find an alternative.
  • Consider using packaging as raw material.
  • Be creative – e.g. if cover boards cannot be reused directly, they might be used for setting up machinery, timber spacers may be usable for structural purposes within the furniture etc.
  • Try to take advantage of one trip pallets which seem to be unsuitable for further usage. Discuss with supplier the take-back possibilities, as well as possibilities for changing them to multi-trip pallets. Also, consider utilizing still usable pallets on goods-out.
  • Discuss using returnable containers with your key supplies to reduce their obligation and costs, and and lower the amount of waste packaging arising at your own site.
  • Consider at which point goods-in should be removed from their packaging. Goods removed from their packaging in storage areas will be more prone to damage. However, it will often become more difficult to collect and segregate packaging when the goods are dispersed to various parts of the factory.
• Woodworking
• Machining waste
  • If machining is unavoidable, use the smallest stock size possible to generate the least waste, as well as reduce processing time and energy consumption, plus decreasing tool wear.
  • Consider purchasing pre-cut timber (which only has to be shaped and finished) for certain items such as legs and arms as it may be more cost effective than buying-in standard sizes of timber which must be cut to shape first.
  • Use only high quality timber to prevent waste from removing defects, or at least smaller pieces of lower quality timber where possible.
  • Optimise cutting patterns via machinery and software, and consider carefully board size specification in the light of forthcoming orders.
  • Standardise component size to reduce awkward lengths and optimise the number of components achievable per section of raw material. Where possible, try resizing those components that may suit regular batches of offcuts.
  • When possible, use offcuts for setting up machines for new batches rather than using and wasting virgin material. Similarly, off-spec products and poor grade timber can be used in this manner.
• Continuous Production
  • Guarantee regular maintenance of machinery to minimise wastage from malfunctions, additional set-ups and restarts.
  • Stagger lunch breaks with the resultant fewer interruptions to achieve the same effect.
• Process Control
  • Assess the working styles of individual operators, identifying the best method and making it the standard.
• Rejects
  • Record and analyse the reasons for rejections. Investigate common causes and make workers aware of the knock-on effect of such problems.
  • Where possible, send rejects for re-work and reuse.
  • When establishing production bonuses, avoid encouraging speed at the expense of accuracy to prevent unnecessary waste in the form of re-work/rejects.
  • Consider establishing penalties for the production of faulty goods.
  • Calculate the amount of value added at each stage of production to get to know the true cost of rejects.
• Coating Operations
  • Ensure lids are put on all coating containers. Open pots lead to increased solvent evaporation and the need for additional thinners that means doubling raw materials.
• Thinners
  • Use solvent only for thinning where essential and not just out of habit or to compensate for poor spraying technique. 
• Cleaning Operations
  • Clean spray lines with water if possible, otherwise investigate the suitability of less volatile solvents. Coating suppliers should be able to advise on optimum cleaning solutions.
  • Reuse the solvent used for cleaning spray guns and lines by capturing it in a container.
  • Aim at using relatively dirty cleaning fluids in additional cleaning or as a pre-wash, if possible. Solvent can still effectively clean when it contains up to 15% solids.
  • Consider investing into your own solvent recovery to recover waste solvents for reuse.
• Spray Efficiency
  • Increase transfer efficiency of guns by correcting spraying pressures, advancing spraying technique and avoiding awkward surface shapes, if possible.
• Packaging on goods-out
  • Analyse whether all packaging is really necessary.
  • Analyse the reasons for returns to identify recurring packaging deficiencies.
  • Consider putting penalties in place for careless delivery personnel that cause higher than expected returns.
  • Consider potential for reusing packaging provided by suppliers.
  • Consider the possibility of your vehicles bringing back your packaging for reuse, particularly applicable in case of office and contract suppliers.
  • Discuss packaging requirements with your customers. As with your own goods in, reducing the volume of packaging through reduction or reuse will lower your company obligation and cost, as well as reducing your customer’s disposal costs.
  • Consider using blanket wrapping, as these covers have the advantage of being reusable many times.
  • Consider using waste from other parts of the business for packaging, e.g. timber offcuts.
• Minimising hazardous waste
  • Always ask for the material safety data sheets when looking for or purchasing a product to look at its hazardous content.
  • Substitute feedstock materials with those having less-hazardous materials.
  • Purchase paints with higher solids content, or water-based paints with no solvent, whenever possible.
  • When buying new equipment, look for equipment that will minimise both the amount of toxic materials used and the amount of waste produced.
  • Use high-volume, low-pressure spray guns for painting operations.

Segregate hazardous and non-hazardous wastes for recycling.

Printing industry

• Inventory:
  • Purchase raw material quantities according to needs as buying in bulk can often reduce packaging waste, and is usually cost-effective. Conversely, buying infrequently used materials in small quantities may prevent waste as a result of expiration.
  • Test out-of-date materials before disposing of them as expiration dates are just estimates. Often the product is still good long after the labelled date. Also, find out if expired or obsolete materials can be returned to the supplier.
• Training:
  • Trained employees on spill prevention and other pollution prevention practices as segregation of wastes, spill prevention and waste minimization can prevent unneeded costs and unnecessary generation of hazardous waste. Moreover, properly trained employees are less likely to misuse costly products, thereby reducing the amount of waste generated by spills and improper handling storage of hazardous materials.
• Materials handling and storage
  • Keep waste segregated, as it is critical to store all wastes separately. Mixing hazardous waste with other wastes makes the whole thing hazardous, thereby increasing disposal costs and liability potential. Mixing wastes may also make recycling or reuse impossible.
  • Keep containers closed and secured all time, unless adding or removing wastes. The containers must also be in good condition and free of leaks. Covering products can help save money be reducing evaporative losses.
  • Use funnels when transferring wastes to storage containers.
  • Store materials properly to prevent possible damage or contamination from heat or cold, excessive light, or excessive moisture. Keep paper stored in an environmentally controlled area.
• Minimise the use of isopropyl alcohol:
  • Determine if fountain solution is hazardous waste. Some components of fountain solutions, such as ethylene glycol, may make spent fountain solution hazardous.
  • Consider metered dampening systems to reduce wastes.
• Substitute inks and/or manage ink effectively to reduce waste:
  • Schedule, when possible, similar-colour jobs simultaneously to reduce waste generation between cleanup and start of next run.
  • Recycle or reuse old inks for marketing as "house colors" (Note that the quality of inks mixed with a variety of additives may be affected over time).
  • Consider computer ink blending programs to minimize waste of special, uncommon inks (This option is more appropriate for larger printers).
  • Try to prevent ink from drying or skinning inside the fountain by good operation practices such as keeping ink containers sealed and contents leveled, as well as anti-skinning sprays can help reduce waste ink.
• Finishing
  • Collect waste solvent and used as thinner.
  • Recycle cleaning solvent.
  • Clean with reusable, launderable shop towels instead of disposable paper, as disposable shop towels are wasteful, and may be disposed of in a landfill only if they are determined to be non-hazardous; otherwise they must be managed as hazardous waste. Launder able rags which do bear free liquids are not subject to hazardous and solid waste regulations.
  • Separate and segregate waste paper and send to a recycler.
  • Consider waste exchanges to find potential users for your off-spec and overstock inks. Local schools, art and theatre departments often have uses for these inks.

Metal industry

• Training:
  • Train employees on spill prevention and other pollution prevention practices as segregation of wastes, spill prevention and waste minimization can prevent unneeded costs and unnecessary generation of hazardous waste. Moreover, properly trained employees are less likely to misuse costly products, thereby reducing the amount of waste generated by spills and improper handling storage of hazardous materials.
• Materials handling and storage
  • Keep waste segregated, as it is critical to store all wastes separately. Mixing hazardous waste with other wastes makes the whole thing hazardous, thereby increasing disposal costs and liability potential. Mixing wastes may also make recycling or reuse impossible.
  • Keep containers closed and secured all time, unless adding or removing wastes. The containers must also be in good condition and free of leaks. Covering products can help save money be reducing evaporative losses.
  • Store materials properly to prevent possible damage or contamination from heat or cold, excessive light, or excessive moisture.
• Keep different types of sludge from wastewater processing separate to facilitate the recycling of valuable materials.
• Right processing (techniques and tools to shape the metal) to avoid oily dragged-, honed- and lapping sludge’s:
  • Use of abrasives with longer life expectancies
  • Use of filter and separation techniques that work without auxiliary materials (e.g. magnetic separators, circulation band pass filters and centrifuges)
  • Use of optimised filtration processes for grinding slurries to produce sludges that are as dry as possible (e.g. pressure/vacuum filtration)
  • Sufficient drainage and de-oiling of the grinding slurry (e.g. longer draining times)
  • Segregation of materials, including separation of materials contaminated with cooling lubricants emulsions from those contaminated with cooling lubricants oils.
• Optimise materials use for minimising metal swarf:
  • Choice of the semi-finished product: The dimensions of the initial semi-finished product should be as close as possible to the final measurements of the finished part. The choice may be limited where only standard sizes are available.
  • Choice of the shaping technique: Depending on the form and function there may be alternatives to cutting from the solid, particularly if cutting degrees are very high, for example deep-drawn sheet steels, sheet steel constructions or cast parts. However it may not be possible to directly substitute one for another.
  • Product design and re-design: The product and/or the components should always be formed in such way that the amounts of waste produced are as small as possible. This can be achieved by switching to more similarly sized semi-finished products or by using other techniques (see above). The design/re-design of a product drives the choice of semi-finished products and techniques.

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IPPC

For the specific topic related BAT/BAP (e.g. chemicals, water, air etc.) refer to the relevant chapter.

There is also a draft BREF (BAT reference document) developed relevant for the printing. Although this document is binding only for large companies (which fall under IPPC directive), also for smaller companies this document can give some ideas for the improvement of own performance: see in English http://eippcb.jrc.es/pages/FActivities.htm)

There are also existing couple of BREFs (BAT reference documents) developed relevant for the metal processing companies. Although these documents are binding only for large companies which fall under IPPC directive, also smaller companies in these documents can find some ideas for the improvement of own performance available at: http://eippcb.jrc.es/pages/FActivities.htm:

• Ferrous Metal processing (formally adapted)
• Non-ferrous Metal processing (formally adapted)
• Smitheries and Foundries (formally adapted)
• Surface treatment of metals (finalised)

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