《纺织复合材料》课程参考文献（Composite Materials Handbook，Volume 3）Chapter 11 Environmental Management

MIL-HDBK-17-3F Volume 3,Chapter 11-Environmental Management CHAPTER 11 ENVIRONMENTAL MANAGEMENT 11.1 INTRODUCTION The objective of this chapter is to provide information for the environmental management of compos- ite materials.Requirements for recycling of all classes of materials are increasing on a global basis and are not likely to be reduced.Many industries have found that taking a proactive approach to environ- mental management of their products can help to head off the enactment of complex regulations,which can be costly and less effective than market based solutions.Reuse and recycling of automobiles and components,for example,is performed by an efficient,nationwide network of used parts shops,automo- bile shredders,and resellers that extracts the maximum value out of recycled vehicles.This network is directed and motivated by interest in the value of the components and materials in end-of-use vehicles, rather than by an innate desire to comply with regulations. The creation of a similar network for composite materials is an ongoing process at this time.It in- volves the development of size reduction and matrix digestion technologies,the organization of a collec- tion system,identification of uses for recycled fibers and matrices,and perhaps most importantly,the education of the composites production and user community about recycling needs and opportunities. Efforts to recycle composite materials are in an early stage of development compared with other as- pects of composite's usage,and so much of the information in this chapter describes immature technolo- gies.They are nevertheless included to provide an overview of the state-of-the-art and a resource for those interested in applying or developing composite reduction,reuse,and recycling technology. 11.1.1 Scope The scope of this chapter is to provide guidance for the environmental management of composite materials as it pertains to the"reduce,reuse,and recycle"paradigm for controlling environmental impact. It does not address issues such as styrene emissions,handling of toxic materials,or disposal require- ments for hazardous waste.Some aspects of composite manufacturing and use,such as lightweighting (defined later),prepreg usage,and the use of hybrid composites,are treated as they pertain to environ- mental management.These aspects will be discussed in this chapter only in the context of recycling,with other parts of the handbook referenced for broader discussions. 11.1.2 Glossary of recycling terms Broad Categories--General classifications of recyclable material,such as glass,plastic,metal,or paper. Broker--refers to an individual or group of individuals who act as an agent or intermediary between the sellers and buyers of recyclable materials. Collector--refers to public or private haulers that collect nonhazardous waste and recyclable materials from residential,commercial,institutional,and industrial sources. Comingled recyclables--refers to a mixture of several recyclable materials in one container. Disposal Facilities--refers to repositories for solid waste,including landfills and combustors,intended for permanent containment or destruction of waste materials. Drop-Off Center--refers to a method of collection whereby recyclable or compostable materials are taken by individuals to a collection site and placed in designated containers. End-of-Service--Components that have been used until failure or obsolescence. 11-1

MIL-HDBK-17-3F Volume 3, Chapter 11 - Environmental Management 11-1 CHAPTER 11 ENVIRONMENTAL MANAGEMENT 11.1 INTRODUCTION The objective of this chapter is to provide information for the environmental management of compos￾ite materials. Requirements for recycling of all classes of materials are increasing on a global basis and are not likely to be reduced. Many industries have found that taking a proactive approach to environ￾mental management of their products can help to head off the enactment of complex regulations, which can be costly and less effective than market based solutions. Reuse and recycling of automobiles and components, for example, is performed by an efficient, nationwide network of used parts shops, automo￾bile shredders, and resellers that extracts the maximum value out of recycled vehicles. This network is directed and motivated by interest in the value of the components and materials in end-of-use vehicles, rather than by an innate desire to comply with regulations. The creation of a similar network for composite materials is an ongoing process at this time. It in￾volves the development of size reduction and matrix digestion technologies, the organization of a collec￾tion system, identification of uses for recycled fibers and matrices, and perhaps most importantly, the education of the composites production and user community about recycling needs and opportunities. Efforts to recycle composite materials are in an early stage of development compared with other as￾pects of composite’s usage, and so much of the information in this chapter describes immature technolo￾gies. They are nevertheless included to provide an overview of the state-of-the-art and a resource for those interested in applying or developing composite reduction, reuse, and recycling technology. 11.1.1 Scope The scope of this chapter is to provide guidance for the environmental management of composite materials as it pertains to the "reduce, reuse, and recycle" paradigm for controlling environmental impact. It does not address issues such as styrene emissions, handling of toxic materials, or disposal require￾ments for hazardous waste. Some aspects of composite manufacturing and use, such as lightweighting (defined later), prepreg usage, and the use of hybrid composites, are treated as they pertain to environ￾mental management. These aspects will be discussed in this chapter only in the context of recycling, with other parts of the handbook referenced for broader discussions. 11.1.2 Glossary of recycling terms Broad Categories -- General classifications of recyclable material, such as glass, plastic, metal, or paper. Broker -- refers to an individual or group of individuals who act as an agent or intermediary between the sellers and buyers of recyclable materials. Collector -- refers to public or private haulers that collect nonhazardous waste and recyclable materials from residential, commercial, institutional, and industrial sources. Comingled recyclables -- refers to a mixture of several recyclable materials in one container. Disposal Facilities -- refers to repositories for solid waste, including landfills and combustors, intended for permanent containment or destruction of waste materials. Drop-Off Center -- refers to a method of collection whereby recyclable or compostable materials are taken by individuals to a collection site and placed in designated containers. End-of-Service -- Components that have been used until failure or obsolescence

MIL-HDBK-17-3F Volume 3,Chapter 11-Environmental Management End User--Facilities that purchase or secure recovered materials for the purpose of recycling.Examples include recycling plants and composting facilities.Excludes waste disposal facilities. Exports--Waste and recyclables that are transported outside the state or locality where they originated. Generators--Producers of solid waste. Imports--Solid waste and recyclables that have been transported to a state or locality for processing or final disposition,but that did not originate in that state or locality. Incinerator--A furnace for burning solid waste under controlled conditions Industrial Process Waste--Residues produced during manufacturing operations. Industrial Waste--Nonhazardous wastes discarded at industrial sites from packaging and administrative sources.Examples include corrugated boxes,plastic film,wood pallets,and office paper.Excludes in- dustrial process wastes from manufacturing operations. Lightweighting--Reduction of system weight by using lighter weight materials,careful design,avoidance of overdesign,and other engineering changes. Large Generator--Commercial businesses,institutions,or industries that generate sufficient quantities of solid waste and recyclables to warrant self-management of these materials. Material Recovery Facility(MRF)--A facility where recyclables are sorted into specific categories and processed or transported to processors for remanufacturing. Mixed Plastic--Recovered plastic that is not sorted into specific categories(HDPE,LDPE....) Nonhazardous Industrial Process Waste--Waste that is neither municipal solid waste nor considered a hazardous waste under Subtitle C of the Resource Recovery Act. Other Plastic--Plastic from appliances,furniture,trash bags,cups,eating utensils,sporting and recrea- tional equipment,and other nonpackaging plastic products. Other Solid Waste--Nonhazardous solid wastes,other than municipal solid waste,covered under Subti- tle D of the Resource Conservation and Recovery Act,such as municipal sludge,industrial nonhazardous waste,construction and demolition waste,agricultural waste,and mining waste. Plastics Handler--Companies that prepare recyclable plastics by sorting,baling,shredding,granulating. and/or storing plastics until a sufficient quantity is on hand. Plastics Reclaimer--Companies that further process plastics after the handling stage by performing at least one of the following functions:washing/cleaning,pelletizing,or producing a new product. Postconsumer Materials/Waste--Recovered materials that have been used as a consumer item and are diverted from municipal solid waste for the purpose of collection,recycling,and disposition.Excludes materials from industrial processes that have not reached the consumer,such as glass broken in the manufacturing process. Preconsumer Materials/Waste--Materials generated in manufacturing processes,such as manufacturing scrap and trimmings/cuttings.Also includes obsolete inventories. Primary recycling-Recycling clean materials and products to produce products that are similar to,or the same as,the original product. 11-2

MIL-HDBK-17-3F Volume 3, Chapter 11 - Environmental Management 11-2 End User -- Facilities that purchase or secure recovered materials for the purpose of recycling. Examples include recycling plants and composting facilities. Excludes waste disposal facilities. Exports -- Waste and recyclables that are transported outside the state or locality where they originated. Generators -- Producers of solid waste. Imports -- Solid waste and recyclables that have been transported to a state or locality for processing or final disposition, but that did not originate in that state or locality. Incinerator -- A furnace for burning solid waste under controlled conditions. Industrial Process Waste -- Residues produced during manufacturing operations. Industrial Waste -- Nonhazardous wastes discarded at industrial sites from packaging and administrative sources. Examples include corrugated boxes, plastic film, wood pallets, and office paper. Excludes in￾dustrial process wastes from manufacturing operations. Lightweighting -- Reduction of system weight by using lighter weight materials, careful design, avoidance of overdesign, and other engineering changes. Large Generator -- Commercial businesses, institutions, or industries that generate sufficient quantities of solid waste and recyclables to warrant self-management of these materials. Material Recovery Facility (MRF) -- A facility where recyclables are sorted into specific categories and processed or transported to processors for remanufacturing. Mixed Plastic -- Recovered plastic that is not sorted into specific categories (HDPE, LDPE....) Nonhazardous Industrial Process Waste -- Waste that is neither municipal solid waste nor considered a hazardous waste under Subtitle C of the Resource Recovery Act. Other Plastic -- Plastic from appliances, furniture, trash bags, cups, eating utensils, sporting and recrea￾tional equipment, and other nonpackaging plastic products. Other Solid Waste -- Nonhazardous solid wastes, other than municipal solid waste, covered under Subti￾tle D of the Resource Conservation and Recovery Act, such as municipal sludge, industrial nonhazardous waste, construction and demolition waste, agricultural waste, and mining waste. Plastics Handler -- Companies that prepare recyclable plastics by sorting, baling, shredding, granulating, and/or storing plastics until a sufficient quantity is on hand. Plastics Reclaimer -- Companies that further process plastics after the handling stage by performing at least one of the following functions: washing/cleaning, pelletizing, or producing a new product. Postconsumer Materials/Waste -- Recovered materials that have been used as a consumer item and are diverted from municipal solid waste for the purpose of collection, recycling, and disposition. Excludes materials from industrial processes that have not reached the consumer, such as glass broken in the manufacturing process. Preconsumer Materials/Waste -- Materials generated in manufacturing processes, such as manufacturing scrap and trimmings/cuttings. Also includes obsolete inventories. Primary recycling – Recycling clean materials and products to produce products that are similar to, or the same as, the original product

MIL-HDBK-17-3F Volume 3,Chapter 11-Environmental Management Processors--Intermediate operators that handle recyclable materials from collectors and generators for the purpose of preparing materials for recycling (material recovery facilities,scrap metal yards,paper dealers....)Processors act as intermediaries between collectors and end users of recovered materials. Quaternary Recycling-Waste-to-energy conversion by incineration. Recovery--The diversion of materials from the solid waste stream for the purpose of recycling.Excludes reuse and source reduction activities. Recyclables--Materials recovered from the solid waste stream and transported to a processor or end user for recycling. Recycling --The series of activities by which discarded materials are collected,sorted,processed,and converted into raw materials and used in the production of new products.Excludes the use of these ma- terials as a fuel substitute or for energy production. Recycling Plant--A facility where recovered materials are remanufactured into new products. Residues--The materials remaining after processing,incineration,composting,or recycling have been completed.Residues are usually disposed of in landfills. Reuse--The use,more than once,of a product or component of municipal solid waste in its original form. Secondary recycling-Recycling mixed materials or products to produce a product that is lower in quality than the original product. Source Reduction--The design,manufacture,purchase,or use of materials,such as products and pack- aging,to reduce the amount or toxicity of materials before they enter the solid waste management sys- tem.This may involve redesigning products or packaging;reusing products or packaging already manu- factured;and lengthening the life of products to postpone disposal.Also referred to as "waste preven- tion." Sortation--The process of sorting comingled recyclables into separate types of materials for the purpose of recycling. Tertiary Recycling--Recycling that is accomplished by completely breaking down a material to its chemi- cal constituents and restoring it to its original quality. Transfer Station--A facility where solid waste is transferred from collection vehicles to larger trucks or rail cars for longer distance transport. Waste Characterization Studies--The identification and measurement(by weight or volume)of specific categories of solid waste materials for the purpose of projecting landfill capacity,determining best man- agement practices,and developing cost-effective recycling programs. Waste Generation--The amount (weight or volume)of materials and products that enter the waste stream before recycling,composting,landfilling,or combustion takes place. Waste Stream--The total flow of solid waste from homes,businesses,institutions,and manufacturing plants that must be recycled,incinerated,or disposed of in landfills;or any segment thereof,such as the "residential waste stream"or the "recyclable waste stream." Waste-To-Energy Facility/Combustor--A facility where recovered municipal solid waste is converted into a usable form of energy,usually through combustion. 11-3

MIL-HDBK-17-3F Volume 3, Chapter 11 - Environmental Management 11-3 Processors -- Intermediate operators that handle recyclable materials from collectors and generators for the purpose of preparing materials for recycling (material recovery facilities, scrap metal yards, paper dealers....) Processors act as intermediaries between collectors and end users of recovered materials. Quaternary Recycling – Waste-to-energy conversion by incineration. Recovery -- The diversion of materials from the solid waste stream for the purpose of recycling. Excludes reuse and source reduction activities. Recyclables -- Materials recovered from the solid waste stream and transported to a processor or end user for recycling. Recycling -- The series of activities by which discarded materials are collected, sorted, processed, and converted into raw materials and used in the production of new products. Excludes the use of these ma￾terials as a fuel substitute or for energy production. Recycling Plant -- A facility where recovered materials are remanufactured into new products. Residues -- The materials remaining after processing, incineration, composting, or recycling have been completed. Residues are usually disposed of in landfills. Reuse -- The use, more than once, of a product or component of municipal solid waste in its original form. Secondary recycling – Recycling mixed materials or products to produce a product that is lower in quality than the original product. Source Reduction -- The design, manufacture, purchase, or use of materials, such as products and pack￾aging, to reduce the amount or toxicity of materials before they enter the solid waste management sys￾tem. This may involve redesigning products or packaging; reusing products or packaging already manu￾factured; and lengthening the life of products to postpone disposal. Also referred to as "waste preven￾tion." Sortation -- The process of sorting comingled recyclables into separate types of materials for the purpose of recycling. Tertiary Recycling -- Recycling that is accomplished by completely breaking down a material to its chemi￾cal constituents and restoring it to its original quality. Transfer Station -- A facility where solid waste is transferred from collection vehicles to larger trucks or rail cars for longer distance transport. Waste Characterization Studies -- The identification and measurement (by weight or volume) of specific categories of solid waste materials for the purpose of projecting landfill capacity, determining best man￾agement practices, and developing cost-effective recycling programs. Waste Generation -- The amount (weight or volume) of materials and products that enter the waste stream before recycling, composting, landfilling, or combustion takes place. Waste Stream -- The total flow of solid waste from homes, businesses, institutions, and manufacturing plants that must be recycled, incinerated, or disposed of in landfills; or any segment thereof, such as the "residential waste stream" or the "recyclable waste stream." Waste-To-Energy Facility/Combustor -- A facility where recovered municipal solid waste is converted into a usable form of energy, usually through combustion

MIL-HDBK-17-3F Volume 3,Chapter 11-Environmental Management 11.2 RECYCLING INFRASTRUCTURE The development of a viable infrastructure for recycling composite materials should ideally be pur- sued as a coordinated effort by composite suppliers,fabricators,and end users.Such an infrastructure will benefit the entire composites industry by improving the efficiency of composite manufacturing,chang- ing the perception that composites are not recyclable and that metals are therefore preferable,and reduc- ing the environmental impact of composites use.This section outlines some of the requirements for recy- cling infrastructure development. 11.2.1 Recycling infrastructure development models The infrastructures for recycling many other materials have already been developed and can provide guidance for the establishment methods for composite materials recycling.Studying these examples can facilitate composites recycling development work and avoid costly mistakes that have been encountered in other industries. One important lesson learned is that while the technology for actually recycling a material is impor- tant,the logistical,educational,and economic issues are equally important.Advanced recycling tech- nologies cannot succeed unless they are integrated with consistent sources of consistent recyclate sources,stable markets for the recycled materials,an efficient collection and transportation system,and a work force that has been educated in the requirements for proper handling of recyclable materials. One of the most mature and efficient reuse/recycling infrastructures is in place for automobiles.A large,computer-integrated network of automobile recyclers procures end-of-service automobiles,re- moves fluids and toxic components such as batteries,catalogues reusable components,and either dis- mantles the vehicle or warehouses its parts in the vehicle.After all reusable components are removed. vehicles are shredded,ferrous metals are magnetically sorted,and lightweight"fluff"and other materials are separated.The result is that approximately 90%of the steel in automobiles is recycled,more than 12 million tons per year.Automotive manufacturers are increasingly paying attention to design for disassem- bly and recycling,and are giving consideration to the recyclability of the materials in their products. A user-subsidized recycling model that may be instructive is that developed for nickel cadmium (NiCd)batteries in response to concerns about groundwater contamination from the cadmium content. Because of the widely dispersed nature of old NiCd batteries,a network of used battery collection centers was created by placing pre-paid,pre-addressed mailers at electronics retail outlets.When the mailers are filled with batteries,they are given to the parcel delivery service and transported to a single recycling facil- ity for the entire North American continent.The recycler distills out the cadmium and processes the nickel content in an open hearth furnace along with other stainless steel waste.The high nickel content in- creases the value of the stainless steel recyclate and helps to pay for the process. In contrast,the vast majority of end-of-service composite materials and composite waste generated in manufacturing,are commonly thrown into landfills (References 11.2.1(a)-(b)).Although this adds only a small volume to the solid waste disposal problem,it returns no value.As regulations that mandate recy- cling of various products take effect,particularly in Europe,non-recyclable materials will be increasingly excluded from consideration.The desirable environmental influence that advanced composites can have, such as greater fuel efficiency from lightweighting,will be lost if recycling techniques are not implemented. 11.2.2 Infrastructure needs Although technologies exist for digestion of composite matrices and recovery of fibers with high strength retention(References 11.2.1(b)and 11.2.2(a)-(d)),these technologies have only been demon- strated on laboratory prototype or pilot scale.Additional efforts to optimize and scale up these processes to complete implementation are underway. A resource recovery network must be established,or "piggybacked"onto existing networks,to collect and channel post-consumer composites back to these material recovery facilities(MRFs).Because of the 11-4

MIL-HDBK-17-3F Volume 3, Chapter 11 - Environmental Management 11-4 11.2 RECYCLING INFRASTRUCTURE The development of a viable infrastructure for recycling composite materials should ideally be pur￾sued as a coordinated effort by composite suppliers, fabricators, and end users. Such an infrastructure will benefit the entire composites industry by improving the efficiency of composite manufacturing, chang￾ing the perception that composites are not recyclable and that metals are therefore preferable, and reduc￾ing the environmental impact of composites use. This section outlines some of the requirements for recy￾cling infrastructure development. 11.2.1 Recycling infrastructure development models The infrastructures for recycling many other materials have already been developed and can provide guidance for the establishment methods for composite materials recycling. Studying these examples can facilitate composites recycling development work and avoid costly mistakes that have been encountered in other industries. One important lesson learned is that while the technology for actually recycling a material is impor￾tant, the logistical, educational, and economic issues are equally important. Advanced recycling tech￾nologies cannot succeed unless they are integrated with consistent sources of consistent recyclate sources, stable markets for the recycled materials, an efficient collection and transportation system, and a work force that has been educated in the requirements for proper handling of recyclable materials. One of the most mature and efficient reuse/recycling infrastructures is in place for automobiles. A large, computer-integrated network of automobile recyclers procures end-of-service automobiles, re￾moves fluids and toxic components such as batteries, catalogues reusable components, and either dis￾mantles the vehicle or warehouses its parts in the vehicle. After all reusable components are removed, vehicles are shredded, ferrous metals are magnetically sorted, and lightweight "fluff" and other materials are separated. The result is that approximately 90% of the steel in automobiles is recycled, more than 12 million tons per year. Automotive manufacturers are increasingly paying attention to design for disassem￾bly and recycling, and are giving consideration to the recyclability of the materials in their products. A user-subsidized recycling model that may be instructive is that developed for nickel cadmium (NiCd) batteries in response to concerns about groundwater contamination from the cadmium content. Because of the widely dispersed nature of old NiCd batteries, a network of used battery collection centers was created by placing pre-paid, pre-addressed mailers at electronics retail outlets. When the mailers are filled with batteries, they are given to the parcel delivery service and transported to a single recycling facil￾ity for the entire North American continent. The recycler distills out the cadmium and processes the nickel content in an open hearth furnace along with other stainless steel waste. The high nickel content in￾creases the value of the stainless steel recyclate and helps to pay for the process. In contrast, the vast majority of end-of-service composite materials and composite waste generated in manufacturing, are commonly thrown into landfills (References 11.2.1(a) - (b)). Although this adds only a small volume to the solid waste disposal problem, it returns no value. As regulations that mandate recy￾cling of various products take effect, particularly in Europe, non-recyclable materials will be increasingly excluded from consideration. The desirable environmental influence that advanced composites can have, such as greater fuel efficiency from lightweighting, will be lost if recycling techniques are not implemented. 11.2.2 Infrastructure needs Although technologies exist for digestion of composite matrices and recovery of fibers with high strength retention (References 11.2.1(b) and 11.2.2(a) - (d)), these technologies have only been demon￾strated on laboratory prototype or pilot scale. Additional efforts to optimize and scale up these processes to complete implementation are underway. A resource recovery network must be established, or “piggybacked” onto existing networks, to collect and channel post-consumer composites back to these material recovery facilities (MRFs). Because of the

MIL-HDBK-17-3F Volume 3,Chapter 11-Environmental Management relatively low volume of advanced composites in service,the most efficient transportation system may include a network of material transfer stations,which collect recyclables for consolidation into large ship- ments.A single transfer station may receive shipments of process waste and post-consumer composites from a state,or metropolitan area,and reship many small loads in a single truck or rail car load. Throughout this consolidation process,different types of composites must remain separate for the value of the recyclables to be maintained.It is almost always easier for materials to be kept separate in the first place than to go through sortation after the fact. 11.2.3 Recycling education Although methods for reducing,reusing,and recycling thermoset matrix composites exist today,and services are available for exchanging unused fibers,prepreg,and other precursors,lack of awareness limits their application.Producers and users should familiarize themselves with opportunities for recycling as a first step in making it a routine part of their ways of doing business.An interest in recycling that is generated in both a top-down and bottom-up fashion can be the most effective in establishing programs, since programs that are mandated by management are likely to fail if not implemented on the shop floor, while individual efforts will not succeed without management support.Information from this chapter and its references can be used as a starting point for this education process 11.3 ECONOMICS OF COMPOSITE RECYCLING A complete discussion of the economics of recycling composite materials would need to address,in detail,numerous issues that are specific to the particular type of composite.Such a discussion is beyond the scope of this section.Some general considerations of composite recycling economics are helpful in designing and evaluating recycling programs and are discussed in this section. The costs of recycling principally arise from collection,transportation,and processing.These costs should ideally be offset by the value of the products derived from the recycled material.There are also costs associated with disposing of waste,called "tipping fees,"particularly if the material is a hazardous waste,as is the case for uncured resins.The reduction or elimination of disposal costs should be consid- ered when evaluating the cost of a recycling operation. In addition,there are significant costs associated with complying with existing environmental regula- tions and those that may be enacted if an industry fails to take action on its own initiative.Some recycling efforts have been initiated by industries to head off legislation that would place a greater burden on them, and result in a less efficient recycling structure.There are significant public relations benefits from mak- ing good faith efforts to recycle and strong negative effects when these efforts are not made.Large-scale implementation of composite materials in the infrastructure,transportation,offshore oil,and other indus- tries will eventually require the further development of composite recycling programs. Several considerations are involved in identifying the most favorable economics for recycling a mate- rial.Minimization of collection and transportation costs is a vital requirement for efficient recycling.For fiberglass materials,for instance,which are heavy,and which do not yield high value recyclate,these costs could be prohibitive.For this reason it is most effective to situate recycling facilities close to the source of material. Derivation of high value materials is another important requirement.Although carbon fiber compos- ites can be completely incinerated for energy,in an open-hearth furnace,for example,their value would be reduced to that of the energy content.Some of the current technologies for fiberglass recycling grind the composite into a fine powder that is used as filler in new composite.This fill must compete with ex- tremely inexpensive calcium carbonate fillers,and is therefore of low value.The primary benefits of these technologies are that the waste does not become a landfill,or disposal problem,and that the recyclate fill is less dense than mineral fill,resulting in a lighter weight composite. 11-5

MIL-HDBK-17-3F Volume 3, Chapter 11 - Environmental Management 11-5 relatively low volume of advanced composites in service, the most efficient transportation system may include a network of material transfer stations, which collect recyclables for consolidation into large ship￾ments. A single transfer station may receive shipments of process waste and post-consumer composites from a state, or metropolitan area, and reship many small loads in a single truck or rail car load. Throughout this consolidation process, different types of composites must remain separate for the value of the recyclables to be maintained. It is almost always easier for materials to be kept separate in the first place than to go through sortation after the fact. 11.2.3 Recycling education Although methods for reducing, reusing, and recycling thermoset matrix composites exist today, and services are available for exchanging unused fibers, prepreg, and other precursors, lack of awareness limits their application. Producers and users should familiarize themselves with opportunities for recycling as a first step in making it a routine part of their ways of doing business. An interest in recycling that is generated in both a top-down and bottom-up fashion can be the most effective in establishing programs, since programs that are mandated by management are likely to fail if not implemented on the shop floor, while individual efforts will not succeed without management support. Information from this chapter and its references can be used as a starting point for this education process. 11.3 ECONOMICS OF COMPOSITE RECYCLING A complete discussion of the economics of recycling composite materials would need to address, in detail, numerous issues that are specific to the particular type of composite. Such a discussion is beyond the scope of this section. Some general considerations of composite recycling economics are helpful in designing and evaluating recycling programs and are discussed in this section. The costs of recycling principally arise from collection, transportation, and processing. These costs should ideally be offset by the value of the products derived from the recycled material. There are also costs associated with disposing of waste, called “tipping fees,” particularly if the material is a hazardous waste, as is the case for uncured resins. The reduction or elimination of disposal costs should be consid￾ered when evaluating the cost of a recycling operation. In addition, there are significant costs associated with complying with existing environmental regula￾tions and those that may be enacted if an industry fails to take action on its own initiative. Some recycling efforts have been initiated by industries to head off legislation that would place a greater burden on them, and result in a less efficient recycling structure. There are significant public relations benefits from mak￾ing good faith efforts to recycle and strong negative effects when these efforts are not made. Large-scale implementation of composite materials in the infrastructure, transportation, offshore oil, and other indus￾tries will eventually require the further development of composite recycling programs. Several considerations are involved in identifying the most favorable economics for recycling a mate￾rial. Minimization of collection and transportation costs is a vital requirement for efficient recycling. For fiberglass materials, for instance, which are heavy, and which do not yield high value recyclate, these costs could be prohibitive. For this reason it is most effective to situate recycling facilities close to the source of material. Derivation of high value materials is another important requirement. Although carbon fiber compos￾ites can be completely incinerated for energy, in an open-hearth furnace, for example, their value would be reduced to that of the energy content. Some of the current technologies for fiberglass recycling grind the composite into a fine powder that is used as filler in new composite. This fill must compete with ex￾tremely inexpensive calcium carbonate fillers, and is therefore of low value. The primary benefits of these technologies are that the waste does not become a landfill, or disposal problem, and that the recyclate fill is less dense than mineral fill, resulting in a lighter weight composite