Washing, compressor

Compressor Wash. When should the eompressor be washed on-line, and when should an off-line eompressor wash should be eonsidered. 

Source Adapted from extracts from Stalder, Gas Turbine Compressor Washing State of the Art—Field Experiences, ASME paper 98-GT-420. 

Based on the evaluation of the above performed measurements and extrapolated to 8000 op.h., it was estimated that improved performance equivalent to approx. US 450,000 per year can he achieved with the combination of both online and offline compressor washing methods on one 30-MW gas turbine the operating and maintenance cost of the S3 tems are not considered in the above figure. 

Results of the improved compressor cleaning regime. Online compressor washes were performed on average eveiy four days at base load with the gas turbine on temperature control mode. Gas turbine performance was measured before and after each wash. 

Jeffs, E., 1992, Compressor Washing On Line for Large Gas TVirbine, TVirbomachineiy International, Vol. 33, No. 6, September/October 1992. 

Stalder, J. E, and van Oosten, E, 1994, Compressor Washing Maintains Plant Performance and Reduces Cost of Energy Production, ASME Paper No. 94-GT-436. 

Propane and light ends are rejected by touting a portion of the compressor discharge to the depropanizer column. The reactor effluent is treated prior to debutanization to remove residual esters by means of acid and alkaline water washes. The deisobutanizer is designed to provide a high purity isobutane stream for recycle to the reactor, a sidecut normal butane stream, and a low vapor pressure alkylate product. 

The ice crystals must be separated from the saline solution surrounding them, and washed with freshwater. This is accompHshed by a downward countercurrent flow of a small amount of freshwater through the ice slurry in the washer—melter unit. Keeping that unit at about 0°C limits the needed pressure rise by the compressor to only about 130—260 Pa, and an auxiUary refrigerator is often used to compensate for heat gains from the ambient and the compression. 

This ammonia is recycled to the reactor via a compressor and a heater. Liquid ammonia is used as reflux on the top of the absorber. The net amount of carbon dioxide formed in the reactor is removed as bottom product from the absorber in the form of a weak ammonium carbamate solution, which is concentrated in a desorber-washing column system. The bottom product of this washing column is a concentrated ammonium carbamate solution which is reprocessed in a urea plant. The top product, pure ammonia, is Hquefted and used as reflux together with Hquid makeup ammonia. The desorber bottom product, practically pure water, is used in the quench system in addition to the recycled mother Hquor. 

Seawater services on onshore platforms, for drinking, washing and firefighting services on off-shore platforms Seawater lift pumps for cooling gas compressors on oil platforms... 

AF tandard 619, Rotary-Type Positive Displacement Compressor American Petroleum Institute, 1975. 

In a typical gas oil design, the lighter products overhead from the quench tower/primary fractionator are compressed to 210 psi, and cooled to about 100°F. Some Q plus material is recovered from the compressor knockout drums. The gases are ethanolamine and caustic washed to remove acid gases sulfur compounds and carbon dioxide, and then desiccant dried to remove last traces of water. This is to prevent ice and hydrate formation in the low temperamre section downstream. 

Heavy plant repairs Vehicle hot washing Vehicle cold washing Public health repairs Store for large tires Service station Electrical repairs Bus washer Vehicle test area Mechanical repairs Tire shop Welding shop Panel beater Radiator shop Paint area Compressor house Tailor Carpenter Store-carpenter Store-tires Store-tailor Store-paint Store-general Adminishation block Filling station Vehicle park... 

Filling station Vehicle park Bus washer Vehicle hot washing Vehicle cold washing Service station Tire shop Store - tires Vehicle test area Compressor house Administration block Store - general Heavy plant repairs Public health repairs Store for large tires Electrical repairs Mechanical repairs Welding shop Radiator shop Panel beater Paint area Store - paint Carpenter Store - carpenter Tailor... 

The hydrocarbon liquid is split. Some is pumped back to the main column as reflux and some is pumped forward to the gas plant Condensed water is also split. Some is pumped back as wash to the overhead condensers and some is pumped away to treating. Some might be used as wash to the wet gas compressor discharge coolers,... 

Install a water-wash system for dilution and removal of cyanide from the unit. Cascading wash water from the high-pressure zone back to the main column overhead or to the first-stage wet gas compressor outlet is attractive, but it is better to use overhead water and pump it from low pressure to high pressure. 

Verify the position of the wet gas compressor spillback. Determine if the compressor turbine needs water washing. Trend the level of inert gases in the dry gas. 

On-line solvent or water wash to minimize blade fouling on both the compressor and turbine. 

If the nurse is responsible for administering the medication by nebulization, it is important to place the patient in a location where he can sit comfortably for 10 to 15 minutes. The compressor is plugged in and the medication mixed as directed, or the prepared unit dose vial is emptied into the nebulizer. Different types of medication are not mixed without checking with the physician or the pharmacist. The mask or mouthpiece is assembled and the tubing connected to the compressor. The patient is placed in a comfortable, upright position with the mask over the nose and mouth. The mask must fit properly so that the mist does not flow up into the eyes. If using a mouthpiece instead of a mask, have the patient place the mouthpiece into the mouth. The compressor is turned on and the patient instructed to take slow, deep breaths. If possible, the patient should hold his breath for 10 seconds before slowly exhaling. The treatment is continued until the medication chamber is empty. After treatment, the mask is washed with hot, soapy water, rinsed well, and allowed to air dry. 

A compressor is required to recover the vapour CO2 from the chamber at the end of the washing cycle, to minimize the loss in CO2 for each cycle (step 5). The vapour is condensed through a heat-exchanger and the liquid is recovered and returned to the storage vessel. The pressure-drop at the end of this step can be larger than 50 bar, with a temperature of the process-fluid higher than 80°C downstream the compressor. 

Figure 9.11-2 Simplified scheme of the high pressure lines for a dry-cleaning CO2 unit. Legend washing chamber, C compressor, CV evaporator or still, ET button filter, FB lint-trap, FT heat-exchanger, HE operative tank, OT additive pump, PA liquid pump, PL vacuum pump, PV storage tank, ST.

At the end of the washing step, the liquid is drained to the operative tank by the pump, and through the button filter, FB, then the gas-recovery step takes place to recover most of the vapour or gaseous CO2 from the chamber. As the gas-recovery can be assumed to be like an adiabatic process, the fluid in the chamber is pre-heated by an electric resistance heat exchanger, HE2, to contain the reduction in temperature. The CO2 vapour is compressed by the oil-free compressor CV and fed to HE1 to condense before being stored in the operative tank. Finally, the chamber is vented and the door can be opened to recover the cleaned garments. 

For GAS experiments the autoclave is filled with the non-volatile component and closed. Then, solvent is drawn into the evacuated vessel. With a pneumatically driven compressor a thermostated buffer vessel is filled with gas. From there it enters the high-pressure cell through the filter or the gas inlet at the top. Thus, the amount of gas can be determined by pvT measurement. Very fast pressure built-up rates can be achieved. After precipitation, the autoclave is placed in vertical position. The solution is then filtered and drained through the bottom valve. During that process the pressure is held constant by adding gas from the top. After the filtration step the solids can be washed with additional gas to remove any residual solvent. 

The cracked gas stream is cooled and purified in the primary fractionator (3) and quench water tower (5). Waste heat is recovered by a circulating oil cycle, generating dilution steam (4) and by a water cycle (5) to provide heat to reboilers and process heaters. The cracked gas from the quench tower is compressed (6) in a 4- or 5-stage compressor and dried in gas and liquid adsorbers (8). C02 and H2S are removed in a caustic-wash system located before the final compressor stage. 

In the Badger/Niro crystallization unit, the xylenes are fed to a single-stage crystallization section that uses continuous suspension crystallization. In this section, the paraxylene is purified with a single refrigerant compressor system, and the mother liquor rejected. The purified paraxylene is fed to a Niro wash column section where ultra-high-purity paraxylene is produced by countercurrent crystal washing. 

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