Process material recovery reuse

One approach to waste reduction is to recover process materials for reuse. Materials used in metal finishing processes can be effectively recovered using available technologies such as dragout, evaporation, reverse osmosis, ion exchange, electrodialysis, and electrolytic recovery.22-26... 

Process material conservation is practiced by the recovery, reuse, or purification of the materials used in the processes. In the nickel deposition process the nickel solution is filtered to reduce its iron content, giving a longer life to the solution. Because the bath is dumped less often, the pollutant load is reduced. 

On-Site Recovery/ Reuse reuse of waste materials or energy streams in the same process or for another useful application within the company... 

As part of the discussion on the use of textile construction membranes, it should be made clear what happens at end-of-Ufe for materials used so far for building construction. Thermoplastic membrane components like PVC can be processed after each utilization period under certain conditions and be supplied for reuse in the raw material cycle. Leading European manufacturers of PVC/PES membranes and roofing sheets have united in order to recycle post-consumer waste, disused membranes and PVC materials (ref. Vinyl) in most modem plants with approved thermo-physical procedures. The output of this recycling process is then used for new products. An important factor in the operation of these and other environmental raw-material recovery procedures is logistics, which includes the materials being carefully prepared and sorted prior to delivery. The processing plants are potentially able to achieve a turnover of more than one ton per hour (ref. recovinyl). 

Abstract Whereas much attention has been paid to the environmental aspects of the life cycle of fuel cell fuel production, emphasis is placed on fuel cell hardware and materials recovery, including component reuse, remanufacturing, materials recycling and energy recovery for fuel cell maintenance and retirement processes. Fuel cell hardware recycling is described and issues related to the recycling infrastructure and the compatibihty of fuel cell hardware and materials are discussed. The role of materials selection and recovery in the fuel cell hfe cycle is described. Future trends for fuel cells centered on voluntary and mandatory recovery and the movement of life cycle considerations from computational research laboratories to design complete the discussion. 

To reduce costs of the more expensive platiag solutioas and decrease the amount of hazardous or regulated material ia a waste stream, recovery and reuse of the drag-out is a common practice. This is done by closing off the water flow to the first tinse tank foHowiag the process tank, and periodicaHy... 

Recovery of materials from liquid effluents, such as processes related to conservation, cleanup, concentration, and separation of desirable fractions from undesirable ones (2) Purification of water sources (3) Effluent water renovation for reuse or to meet point source disposal standards required to maintain suitable water quality in the receptor streams. 

Waste recovery and/or reuse. This comprises the identification and implementation of opportunities to recover process chemicals and materials for direct reuse or for reuse elsewhere through renovation or conversion technology. 

There are advantages to the electrolytic recovery process. For instance, ER units can operate continuously, and the product is in a metallic form that is very suitable for reuse or resale. Electrolytic units are also mechanically reliable and self-operating. Very importantly, contaminants are not recovered and returned to the plating bath. Thus, electrolytically recovered metals are as pure as virgin plating raw material. 

The use of dry spray booths can also reduce the wastewater volume from the plant as well as increasing excess enamel recovery and reuse. Overspray is captured on filter screens and then swept up and reused in the enamel slip. Several plants use this and other, similar processes to recover the enamel raw material. 

Recycled. A material is recycled if it is used or reused (e.g., as an ingredient in a process), reclaimed, or used in certain ways (used in a manner constituting disposal, burned for energy recovery, or accumulated speculatively). 

Pulping liquors. Pulping liquor, also called black liquor, is a corrosive material used to dissolve wood chips for the manufacturing of paper and other materials. To promote waste minimization and recycling, U.S. EPA excluded pulping liquors from the definition of solid waste if they are reclaimed in a recovery furnace and then reused in the pulping process. If the liquors are recycled in another way, or are accumulated speculatively, they are not excluded. 

Splash condenser dross residue. The treatment of steel production pollution control sludge generates a zinc-laden residue, called dross. This material, generated from a splash condenser in a high-temperature metal recovery process, is known as a splash condenser dross residue. Because this material contains 50 to 60% zinc, it is often reclaimed, reused, or processed as a valuable recyclable material. Facilities commonly handle this material as a valuable commodity by managing it in a way that is protective of human health and the environment, so U.S. EPA excluded this residue from the definition of solid waste. 

With the increasing costs of raw materials and the threat of depletion of world reserves of many resources, electrochemical processes should become more attractive to reuse and recycle wastes/materials. The recovery of metals in chemical solutions is very important from both the environmental and economical view points [232]. 

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