Priority chemicals

When designing a process for specialty chemicals, priority tends to be given to the product, rather than to the process. This is because the unique function of the product must be protected. The process is likely to be small scale and operating costs tend to be less important than with commodity chemical processes. The capital cost of the process will be low relative to commodity chemical processes because of the scale. The time to... 

Make suggestions for modification or expansion of the Chemical Priority List by providing lists of chemicals and supporting rationale for their priority to the designated federal officer (DEO). 

Ibid., p. 3354. Inventorship test in chemical priority conflicts. 

Some of the above methods can be miniaturized, and the instrumentation can be adapted for use in field situations (see Section 4 of this book (Potential Use of Screening Methods and Performance Evaluation)), and some can be used only in the laboratory. In the former case a spot sample can be taken, processed and analysed in the field without the need for sample preservation, transport, or storage. Since many of these methods are rapid, they can provide either quantitative (concentration) or qualitative (above or below a threshold) data on water quality in a time-scale that enables a timely and appropriate response (for instance in the case of an accidental spillage) or the rapid mapping of water quality in a wide area. Table 1.3.3 shows the main classes of chemical priority substances and the different methods that can be used for their analysis. 

Table 1.3.3 Main emerging monitoring methods used for chemical priority substances...

Sugimura, K. Yorozu, K. Suzuki, Y. Hayashi, T. Matsunaga, S.-y. EP Patent Application 893455 to Mitsui Chemicals, priority date April 9, 1997. 

Yoshiaki, O. Naofumi, E. Nobuo, O. JP Patent 10231395 assigned to Sumitomo Chemical, priority date Feb 18, 1997. 

S.-Y. WO Patent Application 9738024 to Mitsui Chemicals, priority date April 9, 1997. 

Control technology requirements vary according to the scale of operation and type of emission problem. For instance, electrostatic precipitator design requirements for fly-ash control from 1000-MW coal-fired power boilers differ from those for a chemical process operation. In the discussion that follows, priority is given to control technology for the CPI as opposed to the somewhat special needs of other industries. 

Commodity chemical producers have varying records of performance in appHcations research. It is usually high on the priority Hst when the product is stiU evolving, eg, low density polyethylene in the late 1950s and early 1960s. In times of pinched profit margins, these services often have been dropped, sometimes to be reinstituted, especially if totally new uses appeared. 

The concept of the principal function raises the question of how priority is deterrnined when two or more different functional groups are present. No arbitrary rule can be entirely satisfactory, but an order has been codified in lUPAC recommendations (52—54), and an essentially similar order is used by Chemical Abstracts Service. In general, a higher state of oxidation takes precedence over a lower one, as shown in Table 1. 

New regulations for toxics and priority pollutants frequendy cannot be met by conventional technology. Other physical—chemical technologies must therefore be appHed. 

Chemical Oxidation. Chemical oxidation can be appHed ia iadustrial wastewater pretreatment for reduction of toxicity, to oxidize metal complexes to enhance heavy metals removal from wastewaters, or as a posttreatment for toxicity reduction or priority pollutant removal. 

Known and suspected endocrine disrupting chemicals needed to be ranked in order of priority for possible regulatory action. 

In addition to chemicals covered under TRI, many other chemicals are released. For example, the EPA Office of Air Quality Planning and Standards has compiled air pollutant emission factors for determining the total air emissions of priority pollutants (e.g., VOCs, SO, NO, CO, particulates, etc.) from many refinery sources. The EPA Office of Aerometric Information Retrieval System (AIRS) contains a wide range of information related to stationary sources of air pollution, including the emissions of a number of air pollutants which may be of concern within a particular industry. With the exception of volatile organic compounds (VOCs), there is little overlap with the TRI chemicals reported above. 

Organics Liquid Chemical Biological pH Constituent analysis Halogen content Total suspended solids heavy metals content, Gross organic components (BOD,TOC) Dissolved oxygen Nutrient analysis (NH3, PO4, N03) pH Priority pollutant analysis ORP... 

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