Small containers emptying

Small containers leaking hazardous liquids should be emptied immediately. The contents should be drained by gravity, siphon, or portable pump into a more suitable container. If immediate transfer is unnecessary or impractical, the container can be placed in another receptacle such as one shown in Figure 2-19. The leaky container can then be taken to an area where liquid transfer and cleanup can be performed safely. 

The general subject of warehousing is covered in Section 4.3. This discussion refers only to small containers. Warehousing may refer to empty containers, to those received with the plant s consumables, or to purchased containers that have been filled with the plant s product. Some Scifety considerations refer to the movement and storage of containers, filled or empty others refer to the characteristics of their contents. The following check list covers both considerations, and also covers movement to and from a warehouse ... 

In the case of small containers like bunker fuel tanks, this flow of two-phase mixture of liquid and vapour out of the vent is similar to that of geysering events and may empty the container of liquid. 

The density determination may be carried out at the temperature of the laboratory. The liquid should stand for at least one hour and a thermometer placed either in the liquid (if practicable) or in its immediate vicinity. It is usually better to conduct the measurement at a temperature of 20° or 25° throughout this volume a standard temperature of 20° will be adopted. To determine the density of a liquid at 20°, a clean, corked test-tube containing about 5 ml. of toe liquid is immersed for about three-quarters of its length in a water thermostat at 20° for about 2 hours. An empty test-tube and a shallow beaker (e.g., a Baco beaker) are also supported in the thermostat so that only the rims protrude above the surface of the water the pycnometer is supported by its capillary arms on the rim of the test-tube, and the small crucible is placed in the beaker, which is covered with a clock glass. When the liquid has acquired the temperature of the thermostat, the small crucible is removed, charged with the liquid, the pycnometer rapidly filled and adjusted to the mark. With practice, the whole operation can be completed in about half a minute. The error introduced if the temperature of the laboratory differs by as much as 10° from that of the thermostat does not exceed 1 mg. if the temperature of the laboratory is adjusted so that it does not differ by more than 1-2° from 20°, the error is negligible. The weight of the empty pycnometer and also filled with distilled (preferably conductivity) water at 20° should also be determined. The density of the liquid can then be computed. 

In dmmming and the filling of tank cars and tmcks, where the vessel is initially empty, the amount of material being transferred that could be released by displacement depends on how much evaporates during the filling. Rarely does a material evaporate so quickly that the entire volume of displaced gas is saturated. More likely the initial release at the start of filling contains only a small amount and the concentration increases toward saturation... 

Thermal degradation of isocyanates occurs on heating above 100—120°C. This reaction is exothermic, and a mnaway reaction can occur at temperatures >175° C. In view of the heat sensitivity of isocyanates, it is necessary to melt MDl with caution and to foUow suppHers recommendation. Disposal of empty containers, isocyanate waste materials, and decontamination of spilled isocyanates are best conducted using water or alcohols containing small amounts of ammonia or detergent. Eor example, a mixture of 50% ethanol, 2-propanol, or butanol 45% water, and 5% ammonia can be used to neutrali2e isocyanate waste and spills. Spills and leaks of isocyanates should be contained immediately, ie, by dyking with an absorbent material, such as saw dust. 

Response of Equipment The response of equipment to blast is usually a combination of two effects one is the displacement of the equipment as a single entity and the other is the faihire of the equipment itself. The displacement of the equipment is an important consideration for small, unsecured items—e.g., empty drums, gas cyhnders, empty containers. Most damage resmts from the faihire in part or totally of the equipment or containing structure itself. 

Filling and Emptying Small Nonconductive Containers Subject to capacity limitations described in 5-8.4 it is common to handle flammable liquids in small glass or plastic containers. The following should be considered for frequent indoor liquid transfers of about 0.5 L (approxi-... 

Atoms of these elements have empty J-orbitals in the valence shell. Another factor—possibly the main factor—in determining whether more atoms than allowed by the octet rule can bond to a central atom is the size of that atom. A P atom is big enough for as many as six Cl atoms to fit comfortably around it, and PC15 is a common laboratory chemical. An N atom, though, is too small, and NC15 is unknown. A compound that contains an atom with more atoms attached to it than is permitted by the octet rule is called a hypcrvalent compound. This name leaves open the question of whether the additional bonds are due to valence-shell expansion or simply to the size of the central atom. 

Gases and condensed phases look very different at the molecular level. Molecules of F2 or CI2 move freely throughout their gaseous volume, traveling many molecular diameters before colliding with one another or with the walls of their container. Because much of the volume of a gas is empty space, samples of gaseous F2 and CI2 readily expand or contract in response to changes in pressure. This freedom of motion exists because the intermolecular forces between these molecules are small. 

---