Water, formation fluid mixing

Sedimentary formation waters typically show a dominance of monofunctional species over difunctional species also, ethanoate is generally dominant over other monofunctional species in produced formation fluids unaffected by formation fluid mixing or bacterial degradation (35). 

As shown in Figure 6.5, hydraulic fracturing involves the pumping of fracturing fluid into a formation at a calculated, predetermined rate with enough pressure to generate fractures or cracks in the target formation. For shale gas development, fracture fluids are primarily water-based fluids mixed with... 

To model fluid mixing, we will use the fresh water as a reactant, titrating it into a system containing the saline water and formation minerals. To do so, we pick up the fluid from the previous step to use as a reactant ... 

Fig. 30.1. Volumes of minerals precipitated during a reaction model simulating the mixing at reservoir temperature of seawater into formation fluids from the Miller, Forties, and Amethyst oil fields in the North Sea. The reservoir temperatures and compositions of the formation fluids are given in Table 30.1. The initial extent of the system in each case is 1 kg of solvent water. Not shown for the Amethyst results are small volumes of strontianite, barite, and dolomite that form during mixing.

Coleman ML, Sheppard TJ, Durham JJ, Rouse JE, Moore GR (1982) Reduction of water with zinc for hydrogen isotope analysis. Anal Chem 54 993-995 Connolly CA, Walter LM, Baadsgaard H, Longstaffe F (1990) Origin and evolution of formation fluids, Alberta Basin, western Canada sedimentary basin II. Isotope systematics and fluid mixing. Applied Geochem 5 397 14... 

The pilot test was in the Northwestern block of the Lamadian field. The target formation was in PI1.2. Some of the reservoir, fluid, and well data are shown in Table 5.19. The produced water came from the La400 produced water treatment station it was transported into a pressure container and put in contact with air for 5 minutes before it was transported into a reaction container for 2 hours. Then it was pumped into a water pipeline to mix with a mother polymer... 

Other than the straightforward treatment design cases or where it is otherwise impossible to do so, acid/additive systems should be tested for compatibility with formation fluids (oil and water). It is not always obvious, especially given extreme conditions, how additives will interact with one another and with formation fluids. Service company product and mixing guidelines should not be overlooked. 

The liquid phase of saturated saltwater muds is saturated with sodium chloride. Saturated saltwater muds are most frequently used as workover fluids or for drilling salt formations. These muds prevent solution cavities in the salt formations, making it unnecessary to set casing above the salt beds. If the salt formation is too close to the surface, a saturated saltwater mud may be mixed in the surface system as the spud mud. If the salt bed is deep, freshwater mud is converted to a saturated salt water mud. 

Based on these summaries, the formation mechanism of ore deposits and origin of ore fluids were considered. Mixing of ascending hydrothermal solution and ambient cold water (seawater, groundwater) is considered to be an important depositional mechanism. 

Interpretation of NMR well logs is usually made with the assumption that the formation is water-wet such that water occupies the smaller pores and oil relaxes as the bulk fluid. Examination of crude oil, brine, rock systems show that a mixed-wet condition is more common than a water-wet condition, but the NMR interpretation may not be adversely affected [47]. Surfactants used in oil-based drilling fluids have a significant effect on wettability and the NMR response can be correlated with the Amott-Harvey wettability index [46]. These surfactants can have an effect on the estimation of the irreducible water saturation unless compensated by adjusting the T2 cut-off [48]. 

Even if the reactor temperature is controlled within acceptable limits, the reactor effluent may need to be cooled rapidly, or quenched, for example, to stop the reaction quickly to prevent excessive by product formation. This quench can be accomplished by indirect heat transfer using conventional heat transfer equipment or by direct heat transfer by mixing with another fluid. A commonly encountered situation is one in which gaseous products from a reactor need rapid cooling and this is accomplished by mixing with a liquid that evaporates. The heat required to evaporate the liquid causes the gaseous products to cool rapidly. The quench liquid can be a recycled, cooled product or an inert material such as water. 

---