Water shut off

When water is produced along with oil, the separation of water from oil invariably leaves some water in the oil. The current oil-in-water emission limit into the sea is commonly 40 ppm. Oily water disposal occurs on processing platforms, some drilling platforms, and at oil terminals. The quality of water disposed from terminals remains an area of scrutiny, especially since the terminals are often near to local habitation and leisure resorts. If the engineer can find a means of reducing the produced water at source (e.g. water shut-off or reinjection of produced water into reservoirs) then the surface handling problem is much reduced. 

You can dilute your sample heavily with water. Don t confuse this with drinking water you can also add water directly to the sample. Be sure to use hot water (between 91 and 97 degrees), they will likely take the temperature of the sample. This method is not dependable because some facilities have the sink water shut off to prevent people from doing this. If there is running water, they may listen to you. If you turn on the water, make it sound like you re washing your hands or something. 

Besides borehole sealants for the oil industry, CBS may have other mining and civil engineering applications. These include reinforcement of mined out structures, water shut off, and underground and underwater construction, etc. 

By contrast, water shut-off is generally not adequate unless it is total or nearly so. The choice of grouts for seepage control is selected on the basis of formation void size and effective grout penetrability. 

The requirement of water shut-off and strength increase may be interrelated. The stability of an excavation face or a slope in fine-grained granular material is lowered by the flow of water through the face. Thus water shut-off must be accomplished in order to increase strength. Grout selection for such cases is also based on penetrability. 

Crosslinked polymer-like bulk gel used in water shut-off has very poor flowability the viscosity is very high (>10,000 mPa s). Uncrosslinked polymer is used to increase water viscosity. A movable gel is used in between it has the intermediate viscosity, and more importantly, it can flow under some pressure gradient. Colloidal dispersion gel (CDG) is a typical gel used in these situations. The mechanisms of a movable gel are (1) it has high viscosity to improve mobility ratio like an uncrosslinked polymer solution (2) it has a high resistance factor and high residual permeability reduction factor and (3) it has viscoelasticity so that the remaining oil in the rocks can be further reduced. 

In UTCHEM, the viscosity of the aqueous phase that contains the polymer is multiplied by the value of the polymer permeability reduction factor, F r, to account for the mobility reduction. In other words, water relative permeability, km, is reduced, whereas oil relative permeability, k , is sometimes considered almost unchanged. The reason is that polymer is not soluble in oU, so it will not reduce effective oil permeability. The mechanism of disproportionate permeability reduction is widely used in gel treatment for water shut-off. Many polymers and gels can reduce permeability to water more than to oil or gas. 

Seright, R.S., Liang, J., 1994. A survey of field applications of gel treatments for water shut-off. Paper SPE 26991 presented at III Latin American/Caribbean Petroleum Engineering Conference, Buenos Aires, 27—29 April. 

Figure 1 Scdiematic of flow system. 1) Autotransformer, 2) Blower, 3) Water shut-off valve, 4) Water filter, 5) Dye pun, 6) Flowmeter, 7) Pressure gauge, 8) Drain, 9) Nozzle, 10) Air shut-off valve, 11) Pressure gauge, and 12) Nozzle exit...

The polymers used in EOR may be employed in treatment processes such as mobility control, injection well reprofiling, production well water shut-off, or steam diversion. At temperatures greater than 70-75 C (160-170 F),most water-soluble polymers undergo extensive hydrolysis. As a result, the thickened brine solutions lose viscosity (or in the case of crosslinked gels, they lose gel strength) and are rendered useless . The mechanism of failure is usually precipitation by the reaction of the hydrolyzed polymer with naturally occur ng polyvalent ions. 

Maintenance example A common household water shut-off valve in a home heating system is removed and replaced. Its replacement is part of the routine maintenance of the system and removing and replacing the valve is done without making major alterations to the heating system. The removal and replacement of the valve would be considered maintenance. 

The location of any emergency lighting equipment and any exit route signs The location of any automatic fire fighting system and sprinkler control valve The location of the main electrical supply switch, the main water shut-off valve and, where appropriate, the main gas or oil shut-off valves. 

These results would be interpreted as showing that water breakthrough has occurred earlier in layer B than in the other layers, which may give reason to shut off this layer (as discussed below). The lack of production from layer C may indicate ineffective perforation, in which case the interval may be re-perforated. The lack of production may be because layer C has a very low permeability, in which case little recovery would be expected from this layer. 

Bacteriological sampling is performed by manual techniques because of stringent sterilization requirements. Samples are taken in wide-mouthed, sterile, glass-stoppered bottles that are wrapped in paper prior to sterilization in an autoclave at 138 kPa (20 psi) or in an oven at 170°C. The botde is unwrapped and the lower portion is held in the hand. The sample is taken with the botde mouth in the direction of the flow. The stopper must be protected from contamination, the botde only partially filled, and the sample stored at 4°C after sampling. For bacteriological samples withdrawn from a tap, the water should mn for five minutes and then be shut off the tap should then be sterilized by flaming before a sample is taken. 

This test is prescribed by ANSI C-37/20C for isolated phase bus systems after they have been assembled at site. The test is conducted by filling the enclosure with air up to a pressure of 15 cm of water (1500 N/m ). After the air supply is shut off, the pressure must not drop to less than 7,5 cm of water in 15 seconds. All breathers and drain holes must be sealed before the test. 

An intensive radial load is created when operating near the shut-off head and the shaft deflects at about 60° from the cut-water. This concept is explained in Chapter 9 Shaft Deflection . The pump will be noisy, will vibrate and maintenance on seals, bearings and shaft sleeves is expected. 

Once a fire has started, control of the fire can be accomplished in several ways through water systems (by reducing the temperature), carbon dioxide or foam systems (by limiting oxygen), or through removal of the substrate (by shutting off valves or other controls). Chapter 4 provides detailed discussion on the theories of fire and specific information on hydrocarbons, as well as chemical specific fire characteristics. 

Very flammable gases or very volatile flammable liquids. Shut off flow and keep cooling water streams on expxased tanks or containers. 

Agents Shut off gas source use water to cool adjacent combustibles Fire Extinguishing Agents Not to be Used Data not available Special Hazards of Combustion Products Irritating hydrogen fluoride fumes may form in fire Behavior in Fire Containers may explode. Vapors are heavier than air And may travel a considerable distance Ignition Temperature Data not available Electrical Hazard Data not available Burning Rate Not pertinent. 

Pressure indicators are specified to aid in making adjustments and in evaluating burner performance. Water manometers may be used in this service, but must be shut off when not in use. 

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