Recycling of Industrial Waste

Part III comprises a thorough description of the roles of clays in environmental protection and degradation. The environmental impacts of clay mining, beneficiation and clay-related industries and the natural processes by which clays protect the environment are explained in the initial chapters of Part III. The next chapters introduce the application of clays and their derivatives to resist pollution, recycling of industrial waste products and waste managements (for both toxic and non-toxic wastes). 

Consideration of the cost of investigating or developing methods for the re-use or recycling of industrial waste may appear prohibitive but many companies that have carried out investigations have discovered that not only do they achieve an environmental improvement but the exercise proves economically viable. 

Reverse osmosis is used for desalination of seawater, treatment of recycle water in chemical plants and separation of industrial wastes. More recently the technique has been applied to concentration and dehydrogenation of food products such as milk and fruit juices. See ultrafiltralion. 

Reduction and recycling of waste are inevitably site and plant specific, but a number of generic approaches and techniques have been used successfully across the country to reduce many kinds of industrial wastes. 

Different methods available for material recycling of plastics waste into raw materials for the chemical industry are reviewed and discussed. The technical problems, energy efficiencies and cost efficiencies of the processes are examined. 35 refs. 

With reference to the latest UK government s attempts to tackle the problem of the disposal and/or recycling of packaging waste, comments are reported from Cameron McLatchie, chief executive of British Polythene Industries. He calls for a landfill levy and increased use of incineration with energy recovery. According to recent studies, the capacity for mechanical recycling is presently insufficient. Statistics relating to waste production are included and the case for incineration in the UK is propounded. 

Improved Materials Processing and Recycling Techniques that Reduce Energy Consumption and GHG Production (e.g., reduction of Portland cement use by substitution of industrial waste products such as fly ash, which has several side-benefits). 

Uie recycling of wood waste is also increasingly being used, where timber products at the end of life are usually reduced by chipping, or fibre production, and the resultant material is then reused in reconstituted wood products. Strict monitoring and control are required in order to ensure that inappropriately treated waste is not included in the feedstock stream for recycling wood. The use of recycled wood in reconstituted products is rising rapidly for example, in the UK, the panel products industry used 400 000 tonnes of recycled wood in 1999, and this had risen to 932000 tonnes by 2002 (UK Forestry Commission data 2003). 

Waste water treatment. Supercritical CO2 has been put to use in a variety of industrial waste treatment applications. Clean Harbors Environmental Services, Inc., has used SCCO2 in Baltimore since 1989 to treat wastewater from chemical and pharmaceutical manufacturers. In the process the wastewater is pumped into the top of a 32-ft-high, 2-ft-diameter column, while the CO2 is pumped in from the bottom and percolates up. As the CO2 trowels up it dissolves the organics. CO2 contaminated with organics is at the top of the column, and clean water is at the bottom. The contaminants are incinerated off-site after separation from the CO2 which is recycled. 

They are often produced from many types of industrial waste. This recycling relieves pressure on the environment, as these materials would otherwise have to be disposed of. 

Development of multipurpose industrial units for recycling of plastic wastes by on-line pattern recognition of polymers features (SURE-PLAST) (European Project) BRPR-CT-98-0783... 

Factors That Affect Generation Rates Factors that influence the quantity of industrial wastes generated include (1) the extent of salvage and recycle operations, (2) company attitudes, and (3) legislation... 

A. Tukker (TNO-STB), lug H. de Groot (TNO Industrial Research), lr.L. Simons (TNO-STB), Ir. S. Wiegersma (TNO Industrial Research), Chemical Recycling of Plastics Waste (PVC and Other Resins), TNO-Report STB-99-55 Final, 1999, European Commission, DG 111... 

The amount and rate of plastic waste and resource recovery is shown in Table 26.2 [5], Total plastic waste discharged reached 9900 000 t in 2002. The amount of municipal solid waste exceeded that of industrial waste in 2001 and the difference between them tends to increase. Although the amount of feedstock recycling reached 450 000 t in 2002, it still accounts for only 8.9% of municipal solid waste (MSW). Large amounts of waste plastics are treated by incineration with or without energy recovery both in MSW and industrial waste. 

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