Small-Scale Spills

For small-scale spills, the procedure is to use the appropriate sorbent to soak up the spill. Only the minimum amount of sorbent should be used the method of determining this is covered in Section 15.3. The sorbent should be spread around the perimeter of the spill and swept toward the center. The adsorbent should be shoveled into leak-proof container(s) for subsequent disposal. 

Small-scale spills of hazardous chemicals can occur in laboratories in educational institutions, quality control and testing laboratories, hospitals, greenhouses, and wherever small quantities of hazardous chemicals are handled. Such spills have less potential to cause widespread problems than spills on an industrial scale. However, they pose a risk to the health of workers in the laboratory or at the site of the spill from the inhalation of fumes, from the potential hazards of reactive chemicals, and, in the case of liquids, from slipping on wet floors. It is recognized that small spills should be cleaned up as quickly, responsibly, and efficiently as possible. Workplaces must have a protocol for handling spills and provide spill kits in appropriate locations. It is important that such kits be readily available in locations where they are easily accessed when needed. Furthermore, a plan needs to be in place to guide what is to be done with the residues from cleanup of the spills (National Research Council, 1995). 

Requirements for Effective Handling of Small-Scale Spills... 

One of the most important requirements in handling small-scale spills is speed of reaction. The site of the spill should be isolated and workers not directly involved in the spill cleanup kept at a safe distance. For identifiable spills, the hazards are considered and appropriate personal protection worn with breathing apparatus if necessary. For spills of unknown substances it is best to wear full personal protection, including breathing apparatus. Solids that... 

The key to safe handling of chemicals is a good, properly installed hood, and the referenced book devotes many pages to hoods and ventilation. It recommends that in a laboratory where people spend much of their time working with chemicals there should be a hood for each two people, and each should have at least 2.5 linear feet (0.75 meter) of working space at it. Hoods are more than just devices to keep undesirable vapors from the laboratory atmosphere. When closed they provide a protective barrier between chemists and chemical operations, and they are a good containment device for spills. Portable shields can be a useful supplement to hoods, or can be an alternative for hazards of limited severity, e.g., for small-scale operations with oxidizing or explosive chemicals. 

In this article, RPT incidents in various industries are examined. In each case, both laboratory-scale studies and industrial accidents are covered. In the former, usually only simple spills of one liquid upon another were conducted. The effects of a few vmables were tested to determine if they were, or were not, important in achieving an RPT. The results of the small-scale experiments have led to conceptual hypotheses to clarify the initiation of an RPT—and such concepts have, in turn, provided a tentative set of criteria that must be met to achieve an RPT. 

To summarize, this very simple theory indicates that, for small-scale hydrocarbon spills on water, RPTs may occur if... 

It is reemphasized that the M.I.T. tests and conclusions were based on small-scale laboratory spills of LNG. As will be seen later, the superheat theory requires modification when large LNG spills are considered. 

Enger and Hartman (1972a-d) carried out extensive studies at the Shell Pipeline Corporation. The work was divided into two phases. In the first, or exploratory part, a few small-scale LNG spills were made on water ranging from 273 to 356 K no RPTs were noted. Also in the same phase, several pure liquefied gases were spilled on water. A brief summary of their results is shown in Table V. 

The variable surface currents, which are typical of the Kuroshio area (Hsu et al. 1997, 1998 Mitnik et al. 1996), produced the displacement of a spill of different scales relative to its initial position. The high spatial resolution of SAR data allowed us to detect both the mesoscale and small-scale disturbances of a spill s shape, interpreting them as current-induced. 

The step-like features in area 15 can also be interpreted as current-induced. The arrows in Figure lb show the directions of surface currents in a small-scale elliptical eddy. These currents were responsible for the westward and eastward displacements of the spill band. This cyclonic eddy has a low radar contrast without distinct boundaries similar to the current shift lines 7 and 8. The different scaled eddy-like structures and also the eddy streets were earlier detected in ERS SAR images of the Kuroshio east of Taiwan (Hsu et al. 1997 1998, Mitnik et al. 1996, Mitnik and Hsu 1998). 

Fig. 7. Variation of SAR intensity (arbitrary units) along sections normal to the spill shown in Figure la at the distances of 2.7 km (7a, top) and 34.5 km (7b, bottom) from point B (from west to east), with cross-track average of 1 km and along-track average of 50 m. The decreased SAR intensity in the spill area is due to the damping of the small-scale roughness of the sea surface. The solid lines show average radar backscatter of the sea surface west (1) and east (2) of the spill, and in the spill area (3). The length of line 4 characterizes the width of the spill...

Within the WE-NET project (see section 9.2.1.), Mitsubishi Heavy Industries is planning to conduct small-scale LH2 spill experiments for a detailed investigation of the vaporization phenomena with the purpose to develop and validate respective computer models [29]. 

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