Strength waste

Recently, a new concept in fixed film reac tors that uses an expanded or fluidized bed of particdes as the biomass support medium has been introduced. This reactor type can easily handle both low- and high-strength wastes with most electron acceptors. It will be discussed in detail in a later section. 

TABLE 1 Vendor-Supplied Operating Costs for Industrial Strength Waste Streams... 

Narayanan, B., Suidan, M.T., Gelderloos, A.B. Brenner, R. C. (1993). Treatment of VOCs in high strength wastes using an anaerobic expanded-bed GAC reactor. Water... 

This system is used for the treatment of high strength wastes and is operated at much higher BOD loadings than those in the conventional activated sludge process. There is a shorter hydraulic retention time and shorter aeration periods. 

Anaerobic digesters (conventional first stage) batch microbiological treatment of municipal sludge no mixing use for < 50 m /s. For high strength waste water with COD > 4000 mg COD/L. 

Commonly used biological treatment processes include anaerobic treatment for high-strength wastes (BOD > 2000 mg/L), and a wide variety of aerobic processes including acti-... 

Careful design and control often can solve these problems, but vendors are reluctant to recommend anaerobic mobile systems. Anaerobic systems are much more susceptible to variation in waste stream characteristics and environmental parameters. Fixed anaerobic systems are widely used in industry for treatment of uniform, concentrated biodegradable waste in aqueous waste streams due to the low-cost, low-residual generation and production of usable methane gas. However, application to variable CERCLA waste streams is relatively infrequent. Anaerobic systems have the best potential as a pretreatment step for an aerobic system that would otherwise be unable to process a high-strength waste such as a leachate. 

Witt, E. R., et al, Full-Scale Anaerobic Filter Treats High Strength Waste, Proc. 34th Ind. Waste Conf., Purdue Univ., West Lafayette, IN, 1979. 

Owing to the cycHc nature of the TBRC operation, waste heat recovery from the off-gases is not practical and the SO2 content of the gas varies with the converter cycle. In order to supply a relatively uniform flow and strength SO2 gas to a sulfuric acid plant, a system has been installed at RonnskAr whereby the SO2 from fluctuating smelter gases is partially absorbed in water. During smelter gas intermption, SO2 is stripped with air and the concentrated gas deflvered to the acid plant. 

Concentrate. An action to intensify in strength or purity by the removal of valueless or unneeded constituents, ie separation of ore or metal from its containing rock or earth. The concentration of ores always proceeds by steps or stages. Liberation of mineral values is often the initial step. Concentrate also means a product of concentration, ie, enriched ore after removal of waste in a beneficiation mill. 

The use of alternative fibers depends on the abdity of the fibers to bond to one another with sufficient strength to form a cohesive sheet. However, practical considerations determine whether pulp from a particular plant source is commercially feasible. These include the characteristics of the fiber, such as strength and optical properties, supply, yield of desirable fibers, waste generated, and the abdity to store the fibers without degeneration. 

For special high strength appHcations, ie, up to 69 MPa (10,000 psi), special formulations of Pordand cement concretes have been developed. These ate based on the use of chemical and mineral admixtures. The typical mineral admixtures ate fumed siUca and other po22olanics. The chemical admixtures ate generally chemicals termed supetplastici2ets that allow very low water to cement ratios, ie, between 0.4 and 0.25, and reduce the amount of water needed to provide plasticity or dow to the concrete. PubHc works appHcations take just under 32% of the total Pordand cement market streets and highways represent 68% of this usage, and water and waste account for 23%. 

Vitrified-Clay Sewer Pipe This pipe is resistant to very dilute chemicals except hydrofluoric acid and is produced as standard-strength and extra-strength (ASTM C700). It is used for sewage, industrial waste, and storm water at atmospheric pressure. Elbows, Y branches, tees, reducers, and increasers are available. Assembly is by poured joints which allow for ample angular deflection. Joint com-... 

Analytical Supercritical Fluid Extraction and Chromatography Supercritical fluids, especially CO9, are used widely to extrac t a wide variety of solid and hquid matrices to obtain samples for analysis. Benefits compared with conventional Soxhlet extraction include minimization of solvent waste, faster extraction, tunabihty of solvent strength, and simple solvent removal with minimal solvent contamination in the sample. Compared with high-performance liquid chromatography, the number of theoretical stages is higher in... 

EBCT Empty bed contact time SO Strength of the untreated waste... 

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