Phenolic wastes treatment

Corrective Action Application Fluidized bed incineration has been used to incinerate municipal wastewater treatment plant sludge, oil refinery waste, some pharmaceutical wastes, and some chemical wastes including phenolic waste, and methyl methacrylate. Heat recovery is piossible. 

The process is applicable to Ihe treatment of almost any type of organic waste waters which can serve as food for biological growth. It has been applied to cannery wastes, milk products wastes, corn products wastes, and even phenolic wastes. I11 the treatment of phenolic wastes a special flora is developed which thrives on phenol as food. 

Waste-treatment processes commonly result in the production of solid wastes that must be disposed of safely. Enzymatic treatment is no exception. For example, although enzymatic treatment may not produce as large a quantity of solid products as does biological treatment, some solid residues may be formed, e.g., the polymer precipitates formed during the treatment of phenols with peroxidases, spent adsorbents such as talc, chitin, or activated carbon that are used to eliminate the soluble products of enzymatic reactions, or residues of plant materials such as raw soybean hulls when they are used in place of purified enzymes during treatment. Perhaps, the polymers and adsorbents could be incinerated to recover some energy if the emission of dangerous combustion by-products can be controlled or prevented. The residues of plant materials could potentially be composted and used as soil conditioners, provided that pollutants do not leach from them at substantial rates. To date, none of these disposal problems have been addressed adequately. 

Mao X, Buchanan ID, Stanley SJ (2006) Development of an integrated enzymatic treatment system for phenolic waste streams. Environ Technol 27 1401-1410... 

One of the groups of suspect chemicals in the most active effluents in the survey was the alkyl phenols. However, there are probably several endocrine disrupting chemicals in the effluents and rivers, as different waste treatment plants may feed into the same river. As well as the alkyl phenols, a large number and variety of chemicals have been found to cause this effea, including organochlorine insecticides such as DDT, organotin compounds, phthalate esters, plant products, dioxins, polycyclic aromatic hydrocarbons, PCBs, and as expected natural and synthetic oestrogens. 

Chlorine in elemental or hypochlorite salt form is a strong oxidizing agent in aqueous solution and is used in water treatment for disinfection, and in industrial waste treatment facilities primarily to oxidize cyanide. Chlorine and hypochlorites can also be used to oxidize phenol-based chemicals, but their use is limited because of the formation of toxic chlorophenols if the process is not properly controlled. 

Ozone, an unstable molecule (O3), is a highly reactive oxidizing agent that is approx 10 times more soluble than oxygen on a weight basis. Ozone is used in water treatment for disinfection and in industrial waste treatment to oxidize cyaifide to cyanate and to oxidize phenols and dyes to a variety of colorless nontoxic compounds. Ozonation is best suited for waters and wastewaters that contain low levels of oxidizable material. There are no inherent restrictions on levels of dissolved or suspended solids in the water and wastewater, so long an they do not contain oxidizable material that can compete... 

Use Purification of drinking water industrial waste treatment deodorization of air and sewage gases bleaching waxes, oils, wet paper, and textiles production of peroxides, bactericide. Oxidizing agent in several chemical processes (acids, aldehydes, ketones from unsaturated fatty acids), steroid hormones, removal of chlorine from nitric acid, oxidation of phenols and cyanides. 

Wan, Y.H., Wang, X.D. and Zhang, X.J. (1997).Treatment of high concentration phenolic waste water by liquid membrane with N503 a.s mobile carrier. J. Membr. Sci., 135, 263-70. 

Waste Treatment In addition to the waste treatment applications mentioned earlier under ultrafiltration, there are more applications in the removal of organics and inorganics from synfuel wastes, phenolic wastes, organic acid wastes, and pesticides wastes (Siler Bhattacharyya, 1985). 

The added factor 1/(1 + s/X, s) in Equ. 5.88 represents the toxicity of the substrate at higher concentrations. Let us recall that the condition for calculation of the stationary state with nonvanishing biomass concentration is the relation fx(s) = D. This equation has only one solution if fi(s) is a monotonic function. But with characteristics as in Equ. 5.88, there are two solutions. Together with the washout state ( x, s) we have three stationary states. Two of them are stable ( x, and x, s), one of them is unstable ( x, s). Thus, we have a bistable system. The stationary values of the stable and the unstable stationary state are shown as a function of D in Fig. 6.11. Hysteresis may occur in shift experiments. Figure 6.12 shows how the final biomass concentration depends on the initial concentration. Figure 6.13 demonstrates that the phase plane is divided into two attraction domains. Both domains are touched by a separatrix in which the unstable stationary state lies. Note that, after an external disturbance, the system can cross over the separatrix and shift from one steady state to the other. This bistable behavior is a serious problem in, for example, waste treatment It takes place if substrates such as alcohols, phenols, or hydrocarbons occur in such high concentrations that the utilization of these substrates is inhibited. 

Phenolic wastes. Phenols are an example of a group of compounds which are toxic to microbes (as shown by the use of many as disinfectants) and may therefore be difficult to remove by biological effluent treatment or by natural processes in the aquatic environment. This is especially true of high or widely fluctuating levels of phenols. Hence, chemical methods are often required in these cases. 

Alkylated phenol. The most commonly used alkylated phenol ethoxylates (APE) have included octyl phenol ethoxylate and nonylphenol ethoxylates with 3-11 moles of EO, which were produced by alkylation of butylene dimer or propylene trimer onto phenol and subsequent ethoxylation. They had been used extensively in laundry and hard surfacecleaning applications in the nonionic form, and as the sulfated and phosphated derivatives of the low-mole ethoxylates in a variety of industrial applications. Concerns over the environmental impact of the partial metabolites generated during the waste treatment of these surfactants has prompted their elimination from European consumer product formulations, and their deformulation from most consumer products in North America and elsewhere in the world. 

Phenol, a biocidal compound and the first commonly used disinfectant, is an example of a normally nonbiodegradable substance that can be degraded under appropriate conditions. Acclimated bacteria will break down phenol in dilute water solution. When bacteria are used in waste treatment processes to break down substances such as phenol that are normally biorefractory, acclimated microorganisms are often gathered from sites where the substances in question have been present for some time. For example, sites of crude oil spills serve as sources of bacteria that can biodegrade petroleum wastes. 

Distillation is used in treating and recycling a variety of wastes, including solvents, waste oil, aqueous phenolic wastes, and mixtures of ethylbenzene and styrene. What is the major hazardous waste problem that arises from the use of distillation for waste treatment ... 

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