Spills control methods, chemical

Handling chemical spills requires a good understanding of spill-control methods and their limitations. Unfortunately, many laboratory personnel have misconceptions about how to deal with such spills. In the absence of proper preparation the following problems may result from a chemical spill ... 

Plant Pollution Control Methods — Control of spills and leaks, and recovery and raise of chemicals constitute the major pollution control practices within the paper and allied products industry. The extent of pretreatment required is largely dependent on the extent and effectiveness of the in-plant control processes adopted. 

Analytical chemists are by nature innovators and seekers of improvement. In the development area these qualities are invaluable in optimising method performance. Alas far too often, this desire for continuous improvement spills over into the interpretation of methods for quality control. Here we require consistency of application and rigorous control of processes and procedures. These aspects are anathema for many practitioners of the art of chemical analysis . 

Armour, M.A., Laboratory methods for disposal of toxic inorganic and organic chemicals, in Hazardous Waste Control in Research and Education, Pollution Prevention and Waste Minimization in Laboratories, Reinhardt, P.A. etal., Eds., Lewis Publishers, Boca Raton, FL, 1995, p. 105 Haz. Mat. Spills Tec., 29.7. 

The effectiveness of dilution is highly chemical-specific and must be well conceived and tested. For instance, the improper addition of another material to a spill could cause the rapid evolution of heat, which could accelerate the evaporation rate and make the situation worse. Even with the proper diluent selection, the method and rate of addition are both important for controlling vapor evaporation rates. If water is to be used as a diluent for a material with a high heat of dilution, such as sulfuric acid or oleum, it must be added rapidly and in a large enough quantity to not only effect the dilution, but also serve as a heat sink for the heat of dilution produced. In this way, high evaporation rates for the pool being diluted will be minimized. 

The Du Pont Specialty Chemicals company carried out field tests on mitigation methods for small spills of chlorosulfonic acid and oleum at the Liquefied Gaseous Fuels Spill Test Facility in Nevada during April and May 1992. Sixteen different tests were conducted by spilling about 25 U.S. gallons of 65% oleum. Three different control agents were tested water spray, two new types of foam, and SpUl-X-A agent. The pan was 1.5 in. deep. The results of Aese tests are summarized in Table 37.4. 

The previous discussion has indicated that for 100% PCB, Askarel, or Aroclor, there is only one practical method of destruction—incineration at an ANNEX I (or equivalent) EPA approved facility. There are additional options for destruction or decontamination of PCB-contaiminated liquids. EPA has selectively approved chemical dechlorination for PCB concentrations <1%. Under controlled conditions, a high-efficiency boiler is permitted to burn <500 mg/kg PCB concentrations. PCB concentrations <50 mg/kg are not regulated (except for spills near feed sources). Use as road oil is not permitted. 

The safety data sheet, or SDS, is the primary tool for finding hazard and safety information about the chemicals used in yom workplace. The SDS hsts the hazardous ingredients of a product, its physical and chemical characteristics, its effect on human health, chemicals with which it can adversely react, handling precautions, the types of measru es that can be used to control exposure, emergency and first aid procedm-es, and methods to contain a spill. 

Water spray has been used on large spills of some flammable materials in an attempt to reduce vapor concentration betow the explosive limit. However, water sprayed into a confined area may actually increase the air concentration, possibly creating an explosive mixture of air and the flammable vapor. Before using water spray or other methods to safely control vapor emission or to suppress ignition, obtain trained technical advice, based on specific chemical name identification. 

The principal focus of this book is the mitigation of accidental releases of toxic or flammable materials throu release countermeasures, in particular, postrelease systems. Postrelease systems are designed for control of a hazardous material once it has been released into the environment. Control measures can include passive systems, such as dikes or berms around storage tanks, as well as active methods, such as water-spray or deluge systems installation around a process unit, or q>plication of foam on a chemical spill. However, fire fighting, blast protection and environmental control of response methodolo es are not covered in this guideline. 

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