Coalescing filters

Motor-driven, multistage reciprocating compressors have reportedly been the most popular choice for aeroderivatives. Motor-driven, oil-fiooded screw compressors are also used in some cases. High horsepower, multistage centrifugal compressors, similar to those used at many pipeline compressor stations, may be required for the newer heavy-duty units if the distribution pipeline pressure is insufficient (see Pipelines). Gas turbines have more stringent fuel-gas specifications in terms of cleanliness than do gas-fired boilers. Thus oil- and water-knockout systems, coalescing filters, and fine-mesh filters are used. 

A stable cloud of water ia fuel usually means that a surfactant is present to form a stable water-ia-oil emulsion. Smaller droplets resist natural coalescence processes. A surfactant that is potent as an emulsifying agent is apt to disarm the coalescing filters, aHowiag excess water to be deUvered with fuel. 

The type of oil-removing equipment used may be alum or caustic precoat coke filters, diatomaceous earth filters, or coalescing filters, sometimes employing oleophilic resins as oil strippers. Phenolic formaldehyde demulsifiers are also sometimes used. 

Separating the oil in the emulsion from the detergent solution in a coalescing filter, and recycling the detergent solution... 

Loose media filters can be divided into two broad categories, i e., oil coalescing filters and oil coalescing separators... 

The coalescing filter removes oil by entrapping the small droplets within the interstices of the media. Oil coalesces on the grains and accumulates in the bed starting on the inlet side of the filter and gradually saturates the media... 

An oil-coalescing filter to trap any liquid hydrocarbons or water... 

When sampling hot, wet stack gas, a filter capable of withstanding the gas temperature should be installed in the stack at the tip of the sample line to prevent solids from entering the gas sample line. After the sample is cooled, a coalescing filter is used to remove suspended liquids before the sample goes to the analyzer (Figure 3.7). 

The syngas in the C02 Absorber overhead stream is water-washed and fed to a MEDAL membrane unit. The membrane feed gas is sent to a coalescing filter to remove liquids and is preheated before is enters the permeator. In the permeator, syngas is separated into a hydrogen-rich permeate and the syngas product. The operation of the membrane unit is very simple. The driving force for separation is the difference in partial pressure between the hydrogen in the feed gas and that of the permeate. 

The collection of the pyrolysis oils is difficult due to their tendency to form aerosols and also due to the volatile nature of many of the oil constituents. As the aerosols agglomerate into larger droplets, they can be removed by cyclonic separators. However, the submicron aerosols cannot be efficiently collected by cyclonic or inertial techniques, and collection by impact of the aerosols due to their Brownian or random motion must be utilized. A coalescing filter is relatively porous, but it contains a large surface area for the aerosol particles to impact by Brownian motion as they are swept through by the pyrolysis gases. Once the aerosol droplets impact the filter fibers, they are captured and coalesce into large drops that can flow down the fibers and be collected. 

Another option would be to place several filters in line. Generally the term filter refers to a component that removes larger particulates and moisture compared to filters that are called coalescers. Filters generally won t catch the fine aerosols that the coalescer will trap. 

High efficiency coalescing filters are able to remove 0.1 micron particles and aerosols with about 95% efficiency. The particular coalescer for this system has a borosilicate glass element. 

Stainless Steel coalescing filter 34 pipe, 8 scfm max 100 psi McMaster-Carr 4300K11 1... 

The installation of coalescers/filters to remove liquid and particulates from the fuel gas. The ULNB that depend on inducing internal FGR have small fuel tips. These fuel tips are very susceptible to plugging if the fuel gas is not clean. 

Coalescers/filters may or may not be required to clean up the fuel gas. Burners that utilize FGR as the fuel gas have larger than normal fuel tips, and thus are less susceptible to plugging than standard burner... 

Table 15 shows a comparison of SCWO gaseous effluent with the U.S. hazardous waste incinerator air emission standards. While incinerators require multiple clean-up steps to meet the regulations. SCWO inherently meets all but the particulate standard. The SCWO particulate carryover is due to aerosols from the gas-liquid separator, and (assuming a SCWO system was required to meet the incinerator standards) should be readily removed through the use of a coalescing filter. Not shown in Table 15 is the fact that compared to incineration, SCWO produces far lower levels of the acid rain precursor SO2. 

Secondary components of the system are a gas processing train and gas storage vessel. The gas processing train can include different components such as scrubbers, catalytic combiners, coalescers, filters and flashback arrestors. Its purpose is to remove particulate contamination, purify the gas stream, and remove excess water or other liquids. 

Water, in the form of vapor or droplets, is a common element of many sample streams. Too much water vapor can either overwhelm the mass spectrometer, or present a significant sample transport problem if condensation should occur in the sample line. It is possible to remove water vapor with driers, but one must ensure that other analytes of interest are not being removed as well. Fine water droplets can be removed with coalescing filters, and in some cases large water droplets can be excluded by simply designing the sample line with several right-angle bends. 

Compressed air lines are often fitted with filters, regulators, and lubricators. These are usually installed as a set. The filter may be of standard design, to remove moisture and solids, or a coalescing filter, to remove aerosols of compressor lubricating oil. The purpose of the regulator is to adjust the pressure of the air. The lubricator injects a small amount of oil, which provides downstream lubrication. The regulator is mounted between the other two appliances so that it wUl handle only clean air. 

Add a demister to the return air circuit. A demister is made up of a heat exchanger and a coalescing filter. The return air is first cooled to near the condensing temperature of the volatile. It is then passed through the coalescing filter where the volatile condenses and is filtered from the air. 

Their purpose is to destabilize water-in-oil emulsions found in production. However, they may be of interest in refining upstream from filters or coalescer filters, where processes different from simple coagulation are likely to develop. Organic coagulants are also called "inverse demulsifiers" in production. 

Inspect the coalescent filter and change as required Inspect the charcoal filter and change as required Check and adjust the pressure-reducing valve, record all settings... 

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