Containers reuse

Samples should be collected aseptically in nonpyrogenic containers. Reused depyrogenate glassware or sterile, disposable polystyrene plastics are recommended to minimize adsorption of endotoxin. 

How will the products be packaged Will containers be available for recycle Are any additional wastes generated as a result of the container reuse policy ... 

Containers reused or refilled at least five times... 

The third largest LLDPE film application in North America is industrial liners, greater than 250 million kilograms per year. Industrial liners are used inside cans, drums, cardboard boxes and the like to prevent spillage, contamination, moisture, and ease of container reuse. Important film attributes are puncture resistance, tear strength, and tensile strength. Common LLDPE melt indices are 0.5-2 g/10 min with densities of 0.917-0.930 g/cm. mLLDPE finds little application here because of higher raw material costs. 

Picric acid may be made by gradually adding a mixture of phenol and sulfuric acid at 90—100°C to a nitration acid containing a small excess of nitric acid. The picric acid crystals are separated by centrifugiag, washed, and dried. The wash water is reused to decrease losses owiag to the water solubiUty of the picric acid. A yield of about 225% of the weight of phenol is commonly obtained. 

Steeping. Sheet, roU, or suitably milled flock pulp is metered into a pulper along with vigorously stirred 18% sodium hydroxide solution at 50°C. The resulting slurry, containing about 5% finely dispersed pulp, passes to a buffer tank from which it is metered to a slurry press that sieves out the swollen fiber and returns the pressings soda for concentration correction and reuse. The cellulose reacts with the soda as a complex alcohol to form the sodium salt or alk-ceU. 

The cmsts from the Parkes process are then treated to recover the 2inc contained in the dross for reuse in desi1veri2ing This is done by distillation (qv) and more commonly by vacuum technology. A continuous adaptation of the Parkes process is carried out at The Broken Hill Associated Smelters Pty. (Port Pide, AustraUa). The chemistry of this operation is the same as that for batch desi1veri2ing (22,23). 

For the process step involving handling of spent sulfuric acid, several patents have been issued in which improvements in this step were a main claim. The azeotropic nitration of benzene essentially eliminates the need to reconcentrate sulfuric acid (10,11). The nitration step is carried out at higher than usual temperatures (120—160°C). Because excess benzene is used, the higher temperature allows water to be removed as a water—benzene azeotrope. The water is separated and the benzene phase, containing approximately 8% nitrobenzene, is recycled back into the reactor. The dry sulfuric acid is then reused continuously. 

When antifreeze becomes unsuitable for use, either because of depletion of inhibitors, presence of corrosion products or corrosive ions, or degradation of the fluid, recycling and reuse of the antifreeze, rather than disposal, may be considered. Although ethylene glycol is readily biodegraded in typical municipal waste treatment faciHties, antifreeze disposal becomes problematic because the coolant may contain hazardous quantities of heavy metals picked up from the cooling system. Recycling may be economically preferred over coolant disposal and reduces the concern for environmental impact. 

The reaction vessel (nitrator) is constructed of cast iron, mild carbon steel, stainless steel, or glass-lined steel depending on the reaction environment. It is designed to maintain the required operating temperature with heat-removal capabiUty to cope with this strongly exothermic and potentially ha2ardous reaction. Secondary problems are the containment of nitric oxide fumes and disposal or reuse of the dilute spent acid. Examples of important intermediates resulting from nitration are summarized in Table 3. 

Chlorination was found (172) to be the most suitable and effective method for decolori2ing and reducing the COD of waste dyebaths containing a2o dyes. These findings have been substantiated for chlorination and biochemical purification (173). A study (174) has been done on the technical and economic feasibiUty of a chlorination dye wastewater reclamation system for treating effluent that is suitable for reuse in dyeing of polyester/cotton blends with disperse and direct dyes. 

Process Dewatering Applications RO is usebil in many small appheations where there is a volume of water containing a small amount of contaminant. RO is often able to recover most of the water at a purity high enough for reuse. The waste is concentrated making its disposal less costly, which generally pays for the recovery process. 

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