Containing Wastes

Synthetic Processes. Traditional Solvay plants produce large volumes of aqueous, chloride-containing waste which must be discharged. This fact, in addition to a noncompetitive cost position, is largely responsible for the demise of U.S. synthetic plants. In countries other than the United States, waste is sent to the ocean, rivers, or deep underground wells. The AC and NA coproduct processes produce less aqueous waste than the traditional Solvay and NA mono processes. Related environmental concerns are added whenever a plant complex includes lime quarries and ammonia-producing equipment. 

Until 1990, some flaked iodine and iodine-containing wastes were sublimed to obtain an especially high grade product. This process has been dropped because of quaUty improvements in the standard operations. Sublimed iodine is produced only in small quantities by specialized companies that... 

S. Palmer and co-workers, MetaljCyanide Containing Wastes Treatment Technologies, Pollution Technology Review No. 158, Noyes Data Corp., Park Ridge, N.J., 1988, pp. 373-377. 

The obvious destination for nickel waste is in the manufacture of stainless steel, which consumes 65% of new refined nickel production. Stainless steel is produced in a series of roasting and smelting operations. These can be hospitable to the various forms of nickel chemical waste. In 1993, 3 x 10 t of nickel from nickel-containing wastes were processed into 30 x 10 t of stainless steel remelt alloy (205,206) (see Recycling, nonferrous metals). This quantity is expected to increase dramatically as development of the technology of waste recycle coUection improves. 

The misconception that vinyl gives off dioxin when it is incinerated is misleading. A study conducted by ASME in 1995 (162) found that the presence, or absence, of chlorine-containing wastes in incinerators had no effect on the levels of dioxin produced. Rather, it was found that incinerator operating conditions (primarily temperature) were the key to controlling dioxin formation. More recentiy, German officials examined the issue of incinerating vinyl waste and decided there was no cause for concern (180). 

Condensation scrubbers are intended for use in controlling fine PM-containing waste-gas streams, and are designed specifically to capture fine PM which has escaped a primary PM control device. The technology is suitable for both new and retrofit installations. 

An ultrafiltration plant is required to treat 50m3/day of protein-containing waste stream. The waste contains 0.05% by weight of protein which has to be concentrated to 2% to allow recycling to the main process stream. The tubular membranes to be used are... 

Results are presented of studies of the thermolysis of PVC-containing wastes in which calcium carbonate, calcium hydroxide, sodium carbonate and sodium hydrogen carbonate were used for the capture of chlorine. 2 refs. 

Anandhan, S., De, P.P., De, S.K., Swayajith, S., and Bhowmick, A.K., Thermorheological properties of thermoplastic elastomeric blends of nitrile rubber and poly(styrene-co-acrylonitrile) containing waste nitrile rubber vulcanizate powder, Kautsch. Gummi Kunst., 11, 2004. 

The ideal disposal method is a chemical treatment that can convert hazardous waste into environmentally benign materials. For example, trichloroethylene (CI2 C I CHCl) is highly toxic to aquatic life, but this compound can be made nontoxic by chemical treatment that converts its chlorine atoms into chloride anions. Similarly, the chromium-containing waste from electroplating operations contains highly toxic CrOq anions, but a chemical treatment that converts CrOq into Cr causes the chromium to precipitate from the solution as insoluble Cr (OH). This removal of chromium detoxifies the water. 

An intere.sting example in the context of waste minimization is the manufacture of the vitamin K intermediate, menadione. Traditionally it was produced by stoichiometric oxidation of 2-methylnaphthalene with chromium trioxide (Eqn. (8)), which generates 18 kg of solid, chromium containing waste per kg of menadione. Catalytic alternatives have been reported, but selectivities tend to be rather low owing to competing oxidation of the second aromatic ring (the. selectivity in the classical process is only 50-60%). The best results were obtained with a heteropolyanion as catalyst and O2 as the oxidant (Kozhevnikov, 1993). 

Aluminum Trichloride. In an analogous way, an AICI3 containing waste of isopropylbenzene production [189] can be used as an acid hardener for urea-formaldehyde resins. The waste from the production of isopropylbenzene (via a Friedel-Crafts reaction) contains approximately 200 to 300 g/liter of AICI3. 

V. A. Blazhevich, D. A. Khisaeva, V. G. Umetbaev, and I. V. Legostaeva. Polymer plugging solution for oil and gas wells—contains urea-formaldehyde resin, and aluminium chloride containing waste of isopropylbenzene production as acid hardener. Patent SU 1763638-A, 1992. 

S. D. Dzhanakhmedova, E. I. Pryanikov, S. A. Sulejmanova, K. K. Mamedov, E. G. Dubrovina, N. M. Indyukov, and A. B. Sulejmanov. Composition for preventing asphaltene-resin-paraffin deposits—contains waste from production of synthetic glycerine, in mixture with polyacrylamide. Patent SU 1761772-A, 1992. 

M. I. Khoma. Composition of foam-extinguishing agent for drilling solutions—contains waste from production of hydrophilic and hydrophobic aerosil, modified with bifunctional silico-organic compound and diesel oil. Patent SU 1795977-A, 1993. 

V. G. Mosienko, Y. I. Petrakov, A. M. Pedus, and V. N. Nikiforova. Complex additive to plugging solution—contains waste from production of sebacic acid, ammonium sulphate and carboxymethyl cellulose, reducing water separation, etc. Patent RU 2078908-C, 1997. 

Copper concentration Copper ore, water, chemical reagents, thickeners Flotation wastewaters Tailings containing waste minerals such as limestone, and quartz... 

The combustion unit must demonstrate a DRE of 99.99% for each POHC in the hazardous wastestream. This means that for every 10,000 molecules of the POHC entering the unit, only one molecule can be released to the atmosphere. In addition, due to an increased threat to human health and the environment posed by certain dioxin-containing wastes, the required DRE for POHCs in these units has been established at 99.9999%, or one released molecule for every one million burned. These DRE standards must be met by both incinerators and BIFs. 

Inherently waste-like. Some materials pose such a threat to human health and the environment that they are always considered solid wastes these materials are considered to be inherently waste-like. Examples of inherently waste-like materials include certain dioxin-containing wastes. 

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