Pump Installation Safety

To lessen the risk of pumping sludges or slurries into a unit, the practice is to leave a safety margin of 50 cm (heel) below the outlet nozzle or install a strainer on the pump suction line. The deposits accumulate with time and the tanks are periodically emptied and cleaned. 

For example, increasing a valve size or installing a larger pump could result in high pressure in a vessel, thus increasing the risk of a release. Sanders (1993) presents a number of examples of changes affecting the safety of a plant. 

All data recorded in the data base have been acquired from plant records. Statistical reductions of data for generation of reports or specific end use are available. Data are currently collected from four operating plants (eight units). Time clocks have been installed on components, to record actual exposure time. Event data are available on a broad variety of safety and commercial grade components including pumps, valves, transformers, diesels, filters, tanks (vessels), and heat exchangers. 

The checking and readjustment as necessary of all safety controls is an essential part of periodic maintenance - possibly annually. A time should be chosen when temporary stoppage of the plant will not cause inconvenience. Unsafe conditions can be set up by throtding valves, stopping pumps, or removing the load. In each case the relevant safety control should function at the pre-set conditions. Safety checks on specialized items such as fire dampers may be required from time to time by local authorities, and these checks, together with the expert advice available from the testing officers, should be welcomed as proof of the inherent safety of the installation. 

The major difference in supercritical fluid chromatography and conventional LC equipment is the pumping systems as well as the safety features installed to maintain higher pressure. Unique SFC equipment differences are ... 

The exhaust from a rotary pump, especially if it is being run in the ballast mode, i.e. pumping a fair quantity of air or other gas, is an aerosol of oil in the gases from the line. A variety of filters is now available commercially for cleaning exhaust gas, but a good additional safety precaution is a wide tube fitted to the outlet so that the gas stream can be vented to the nearest fume-cupboard or window. The pumping efficiency of a rotary pump drops off rapidly below ca. 10 Torr even under optimum conditions, and such pumps are therefore usually installed as a back-up to a more efficient high vacuum pump, such as a diffusion or a turbomolecular pump. 

Figure 6. Block drawing of the pilot installation for the production of trichloromethyl chloroformate by exhaustive photochlorination [39] 1 Dryer for gaseous Cl2 (H2S04 cone.). 2 Safety tank. 3 Thermoregulated immersion-type photochemical reactor. 4 Raschig column. 5 Cl2 detection system (1,2,4-trichlorobenzene). 6 Neutralization tank (20% NaOH). 7 Reservoir of 20% NaOH. 8 Buffer to atmospheric pressure (20% NaOH). 9 Active carbon filter. 10 Reservoir of crude trichloromethyl chloroformate. 11 Buffer to normal atmosphere via CaCl2 filter and direct entry for trichloromethyl chloroformate to be distilled. 12 Distillation flask with Vigreux column. 13 Exit to vacuum pump. 14 Solid NaOH filter before pump. 15 Cooling water alarm linked to power supply of the light source. 16 Medium pressure mercury arc. 17 Heater for distillation apparatus. 18 Magnetic stirrers. /T thermometer /P manometer.

Aircraft engines Ceramic turbine nozzles in the APU (Auxiliary Power Unit Engine). Seals runners installed in different business jets such as Falcon, Citation and Learjet. Ceramic oil pump spacer enhance engine could start capability on APUs on Boeing 777 and 737 and all Airbuses. Cutter pins, which are used as a safety feature for air turbine starters. Ceramic wear indicator on Airbus APU starter brushes since 1997... 

Figure 3. The diagram of cold generating installations [4] HWT - constant-temperature chamber of hot water CWT - tank of cooled water (liquid) HTS1, HTS2 - high-temperature sorber LTS1, LTS2 - low-temperature sorber T01-T04 - sorber heat exchanger HI, H2-pump F - filter B1 - B27 - valves Ml - M5 -manometers KP1, KP2 - safety valves P -flowmeter T1-T14 - thermocouples.

SAFETY AND MONITORING INSTALLATIONS ON HIGH-PRESSURE CANNED-MOTOR CENTRIFUGAL PUMPS... 

Circulation of the SCO2 is driven by a magnetically coupled gear pump. Micropump Model 183HP-346, specially modified by the manufacturer for operation up to 5000 psi. A 40-pm filter (FI) is installed upstream of the pump, and a 2- um sintered metal filter is located downstream to prevent solids from entering the sample valve. A safety rupture disk (PSE), rated at 4300 psi, protects... 

Technical service groups in this field also use engineers. These men are frequently sent into the customers plants by a raw material supplier to assist in the design and/or installation of tankage, pipe lines, valves, pumps, and the like, thus implementing the suggestions in the safety manual. Classes are frequently held for the customer s personnel, so that they may learn firsthand how to handle these chemicals. 

The use of water pumps in sampling equipment presents no problems under laboratory conditions with respect to performance and the vacuum obtained. For safety reasons as well as the considerable water consumption, their long-term use is, however, avoided. Their principal disadvantage is that they cannot be installed under field conditions. 

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