Waste Material Reuse

Nowadays there are more and more demands to reuse waste materials, especially in the case of polymers. Our research seeks to reveal the oxidative degradation processes of poly(vinyl chloride) (PVC), which may provide new methods for treating and recycling of PVC waste materials. 

The economic balance must be considered between recovery, reuse, and modification of a waste material or by-product and its disposal. The future is expected to bring iacreases ia the practice of recycle, recovery, modification, and upgrading of wastes of all sorts, and a reduction ia disposal by iaciaeration (qv), biochemical oxidation, or discharge to the environment (see Recycling). 

Recychng (or reuse) refers to the use (or reuse) of materials that would otherwise be disposed of or treated as a waste product. A good example is a rechargeable battery. Wastes that cannot be directly reused may often be recovered on-site through methods such as distillation. When on-site recoveiy or reuse is not feasible due to quality specifications or the inability to perform recoveiy on-site, off-site recoveiy at a permitted commerci recoveiy facihty is often a possibility. Such management techniqiies are considered secondaiy to source reduc tion and should only oe used when pollution cannot be prevented. 

Manual Component Separation The manual separation of solid-waste components can be accomplished at the source where solid wastes are generated, at a transfer station, at a centralized processing station, or at the disposal site. Manual sorting at the source of generation is the most positive way to achieve the recoveiy and reuse of materials. The number and types of components salvaged or sorted (e.g., cardboard and high-quality paper, metals, and wood) depend on the location, the opportunities for recycling, and the resale market. There has been an evolution in the solid waste indus-tiy to combine manual and automatic separation techniques to reduce overall costs and produce a cleaner product, especially for recyclable materials. 

The reuse or recycling of wastes can reduce the amount of freshwater and raw materials required for a process. While looking at the inputs to unit operations, think about the opportunities for reusing and recycling outputs from other operations. Note that if reused wastes are not properly documented, double-counting may occur in the material balance, particularly at the process or complete plant level that is, a waste will be quantified as an output from one process and as an input to another. 

To keep product yield at a maximum it is important that the solubility of product in the spent acid be kept to a minimum. This also facilitates removal of traces of product from the spent acid so that it can be either fortified and reused, reused to make lower nitro compds, or neutralized and discharged as non-polluting waste material... 

The eonversion of plasties into elean liquid hydrocarbons includes eraeking of the large polymer molecules as well as the separation of ehlorine in ease the waste material eontains PVC. The liquid hydroearbons generated are praetieally free of ehlorine and ean be direetly reused as petroehemieal feedstoek. The use of the VCC proeess is deseribed in detail. 

Although none of the three laws or their implementing regulations directly addressed the reuse of waste materials, they necessitate a series of evaluations in the reuse program of solid waste, which include the preparation of an environmental assessment, a human health risk assessment, or an ecosystem risk assessment. 

Many facilities in this industry use in-plant technology to reduce or eliminate the waste load, requiring end-of-pipe treatment and thereby improve the quality of the effluent discharge and reduce treatment costs. In-plant technology involves water reuse, process material conservation, reclamation of waste enamel, process modifications, material substitutions, improved rinse techniques, and good housekeeping practices.3-615... 

Used oil distillation bottoms. When used oil is recycled, residues (called distillation bottoms) form at the bottom of the recycling unit. To promote the recycling of used oil and the beneficial reuse of waste materials, U.S. EPA excluded these residues from the definition of hazardous waste when the bottoms are used as ingredients in asphalt paving and roofing materials. 

When viewing effluent treatment methods, it is clear that the basic problem of safely disposing of waste material is, in many cases, not so much solved but moved from one place to another. If a method of treatment can be used that allows material to be recycled or reused in someway, then the waste problem is truly solved. However, if the treatment simply concentrates the waste as concentrated liquid, slurry or solid in a form that cannot be recycled, then it will still need to be disposed of. Landfill disposal of such waste is increasingly unacceptable, and thermal oxidation causes pollution through products of combustion and liquors from scrubbing systems. The best method for dealing with effluent problems is to solve the problem at source by waste minimization. 

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]. 

An important and recently reported issue, namely slow sorption/desorption rates, their causes at the intra-particle level of various solid phases, and how these phenomena relate to contaminant transport, bio availability, and remediation, is also discussed and evaluated. A case study showing the environmental impact of solid waste materials which are mainly complex organic mixtures and/or their reuse/recycling as highway construction and repair materials is presented and evaluated from the point of view of sorption/desorption behavior and data modeling. 

To conform to the organic principles of sustainability, always try to reuse and recycle waste materials from your own garden and locality. One exception to this rule is to dispose of any unsuitable pesticides and herbicides as soon as possible. However, you must not add... 

Unlike common industrial parks where factories are selected simply on the basis of their willingness to share the real estate, environmentally balanced industrial complexes (EBIC) are a selective collection of compatible industrial plants located together in a complex so as to minimize environmental impacts and industrial production costs [24,33]. These objectives are accomplished by utilizing the waste materials of one plant as the raw materials for another with a minimum of transportation, storage, and raw materials preparation costs. It is obvious that when an industry neither needs to treat its wastes, nor is required to import, store, and pretreat its raw materials, its overall production costs must be reduced significantly. Additionally, any material reuse costs in an EBIC will be difficult to identify and more easily absorbed into reasonable production costs. 

Recycle by use, reuse, or reclamation those potential waste materials that cannot be eliminated or minimized... 

The Environmental Soil Management, Inc. (ESMl), low-temperature thermal desorption (LTTD) process is an ex sim, thermal technology that treats soils contaminated with petroleum and nonpetroleum hydrocarbons. LTTD heats contaminated waste material in a rotary dryer to temperatures between 500 and 800°F. Contaminants are volatilized and destroyed in a thermal oxidizer. The treated soil becomes the property of ESMl or is returned to the client for reuse. 

Resource recovery to capture waste materials and reuse them. 

R.D. Pascoe, Physical separation of plastics, in R.K. Dhir, M.D. New-lands, and J.E. Halliday, eds., Recycling and Reuse of Waste Materials, pp. 173-188, London, 2003. Thomas Telford. International Symposium 9-11 September 2003, University of Dundee, Scotland. 

Rinse Efficiency Drag-oul Reduction Recycling and Resource Recovery Waste Material Reuse Rinse Water and Process Bath Recycling Treatment Alternatives Water Supply Treatment Water Segregation... 

As this process is an "on cost" to production, the cleaning must be done in a manner to keep the costs down while still maintaining quality. Dirty solvents can be reused until they will not clean efficiently. The solvents must be kept dry to prevent the dissolved prepolymer from coming out of solution. All final waste material must be disposed of in accordance with local regulations. 

Many mills have successfully controlled their wash water in the softwood industry and there are some in the hardwood plywood industry that are recycling wash water. Wash water from hardwood plywood is an acid-catalyzed solution or mixture and presents another problem. Usually, the resin solids are allowed to settle and the water above reused and the sump solids removed and disposed of in another manner, such as burying the material or burning the solids in a boiler. However, the latter has presented problems within boiler fire chambers. Zero water discharge philosophy is a debatable subject but its application is practical and reasonable in most cases. By recycling or transfer from one source to another, or with pools for evaporation, the water waste materials are contained to prevent discharge into navigable streams. 

Onsite recycling It is the reuse of waste materials at the site of generation. It may be used in the same or another process (like the reuse of cleaning washes and of solvents in the production process). This type of recycling reduces the cost of raw materials as well as the cost of waste disposal. 

The suitability of a waste for recycling depends mainly on the purity, concentration, and chemical form of the reusable material in the waste. For this reason, some waste materials must be treated before being recycled. This treat/ purify-then-recycle option is less desirable than direct in-process recycling/ reuse without treatment [20-23,25,50], as follows ... 

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