Liquids leaks

Wear rings provide for a close running, renewable clearance, which reduces the amount of liquid leaking from the high pressure zones to the low pressure zones in the pump. They are commonly fitted in the pump easing and on the impeller (Figure 16-1, next page). 

Refrigeration, like dilution, reduces the vapor pressure of the material being stored, reducing the driving force (pressure differential) for a leak to the outside environment. If possible, the hazardous material should be cooled to or below its atmospheric pressure boiling point. At this temperature, the rate of flow of a liquid leak will depend only on liquid head or pressure, with no contribution from vapor pressure. The flow through any hole in the vapor space will be small and will be limited to breathing and diffusion. 

On one plant, liquid leaks drained into a sump that was fitted with a level detector. When a leak actually occurred, it dripped onto a hot pipe and evaporated and was not detected for many hours (see Section 20.2.4). 

Electric cables that detect liquid leaks are available. They can be run through areas where leaks are possible, and they indicate the presence and location of a leak. 

Are containers placed in the 6 o clock/12 o clock position for storage to reduce the chance of a liquid leak through the valve ... 

In process operations where relatively small flammable or combustible liquid leaks are expected or considered possible, hand-held fire extinguishers... 

In the event of a leak, a sludge leak is easier to contain than a liquid leak. 

An anecdote illustrates Tishler s drive. The total synthesis of cortisone, as devised by Lewis Sarrett, comprised approximately 30 steps and required weeks of intense and painstaking effort. Max was in charge of the first commercial production of cortisone in the pilot plant. One of the final steps is the isomerisation of a double bond into conjugation with the 3-ketone function with the formation of a 2,4-dinitrophenylhydrazone, causing the development of a brilliant, scarlet color. Tishler was inspecting the first production run. To his horror, he spotted a bright-red liquid leaking near the vessel. "I hope that s blood ", he exclaimed. Actually, Max was very concerned for individuals, beneath a rather formidable exterior. 

An automated solvent controller is available in the latest ASE system. It allows up to four solvents to be mixed and delivered to the extraction cells. This can reduce the time for measuring and mixing solvents and decrease users exposure to toxic solvents. The solvent controller can be programmed to change solvents between sequential extractions of multiple samples. The same sample can also be reextracted using different solvents. The ASE system has many built-in safety features, which include vapor sensors, liquid-leak detectors, vial overfill monitors, electronic and mechanical overpressurization prevention systems, solvent flow monitors, and pneumatic source pressure monitors. 

Dry ice comes in blocks that are wrapped in paper and are kept in specially insulated ice boxes. Because there is no liquid stage of C02 at STP, there is no fear of liquid leaking out of these paper containers (the triple point of dry ice is at 5.2 atm and -57°C). 

At shutdown, any hot liquid lines (e.g., bottom line from another column) must be blinded and any hot liquid drained prior to steaming out. In one incident (3), hot liquid leaked into a column and contacted condensate that formed when an upstream unit was steamed into the column. This caused a pressure surge and extensive tray damage. 

Hydraulic systems for die-casting use water-glycol mixtures, sueh as hydraulic liquid. Leaks in the hydraulie system and consequent transport of the leaked liquid into the water system eould lead to the presence of glycols in the foundry waste water. Removal of the glycol is not possible using filtration or flotation techniques. 

Whether it s a solid or a liquid leak or spill, you can be exposed to toxic dust or vapor without even knowing it. If you are properly trained, act with care and speed. However, if you have not received training, do not respond to a chemical leak or spill. Instead, follow your company s emergency action plan for reporting leaks and spiUs and evacuating. 

For process equipment, designers need to specify necessary safety features and the tests for meeting requirements. For process equipment, there should be fail-safe features. Fire protection, overpressure, excess heat, runaway reactions, dust control, exhaust ventilation, dangers of flammable liquids, leaks, sensing devices to report status are all examples of important safety features. Designers and purchasers need to consider access for setup, maintenance and cleaning. There may be a need for access by stairs, fixed ladders or platforms as part of large equipment. 

Liquid loss the filled and closed container is inverted and checked for liquid leaks. Application of a vacuum helps to identify a poor seal. 

In lithium secondary batteries, the liquid electrolyte impregnates a porous separator. If the enclosure is broken, there is a danger of the liquid leaking. 

If a chlorine container is leaking in such a position that chlorine is escaping as a liquid, the container should be turned if possible so that chlorine gas escapes instead. The quantity of chlorine escaping from a gas leak is about one-fifteenth the amount that escapes from a liquid leak through the same size hole. Leaks at valve stems are often stopped by tightening the valve packing nuts or closing the valve. 

Significant liquid leaks in fluorocarbon systems may be detected visually. As the material escapes, moisture in the air surrounding the leak condenses and then freezes around the leak due to the refrigerating effect of the vaporizing fluorocarbons. The frost thus formed is readily apparent. 

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