Plume injection

Reinjection of coproduced groundwater through the use of wells is commonly used to return the water to the same aquifer and to set up hydraulic barriers in an effort to contain the plume. Injection wells are commonly used in conjunction with withdrawal systems to enhance the recovery of hydrocarbons. Injecting water at appropriate locations will create a pressure ridge to increase the hydraulic gradient effectively toward the withdrawal point. Normally, the water pumped from the recovery wells is used as the injection water and is injected, without treatment. This method provides an economical way of handling the produced water, as well as being beneficial to the recovery effort. 

Micro-plume Injection Mixing Most Relevant Citations... 

By feed of a fluid through a nozzle array, which is a plate with many tiny holes, so-called micro-plume injection into a micro channel can be achieved [51, 147]. Typically, the micro channel s floor is perforated in a section in this way and a closed-channel fraction follows for completion of mixing. Large specific interfaces can in principle be achieved depending on the nozzle diameter. This mixing concept benefits from conceptual simplicity and fits well to existing MEMS techniques. Furthermore, it consumes less footprint area and therefore does not create much dead space, which is one of the prime requirements during pTAS developments. 

Mixer 65 [M 65] Micro-plume Injection Micro Mixer... 

Figure 1.134 Schematic of the micro-plume injection mixer design (newly drawn following...

Mixer type Micro-plume injection mixer Hole depth of the sieve 10-30 pm... 

P 57] A fluorescent dye was injected through the sieve of the micro-plume injection mixer [51]. The changes in fluorescence intensity thereafter in the mixing chamber were monitored by using a fluorescence microscope. 

Plume Containment. WeUs can be placed at a contaminated site to prevent the contamination from spreading further or migrating offsite. In the past, containment efforts often reHed on physical methods such as bentonite slurry trenches, grout curtains, sheet pilings, weU points, and fixative injections. Containment by judiciously placed weUs generally costs less, takes less time to install, and is more flexible because pumping rates and locations can be varied. 

Pour typical weU patterns for contaminant plume containment are described in Ref. 16. The first is a pair of injection-production weUs. The second is a line of downgradient pumping weUs. The third is a pattern of injection-production weUs around the boundary of a plume. The fourth, the double-cell system, uses an inner ceU and outer recirculation ceU, with four ceUs along a line bisecting the plume in the direction of flow. Two other methods of plume containment are bio filters and a fuimel-and-gate system, which are described in the in bioremediation section. 

In situ oxygen supply requires aeration wells for the injection of oxygen. The criteria are that the aeration well zone must be wide enough to allow the total plume to pass through, and the flow of air must be sufficient to produce a substantial radius of aeration while small enough so as not to create an air barrier to groundwater flow. The required residence time tr for aeration can be calculated from Darcy s law as a function of the groundwater head and hydraulic conductivity ... 

Larkin, R.G. and Clark, J.E., Modeling density changes in hazardous disposal well plumes, in Underground Injection Science and Technology, Tsang, C.F. and Apps, J.A., Eds., Elsevier, New York, 2007. 

A recirculation system extracts contaminated groundwater from the site, adds to or amends the extracted water ex situ, and reinjects the activated water to the subsurface, generally upgradient of the contaminated zone. As an alternative, extraction and injection are performed at different elevations in a single well, creating vertical circulation. A groundwater recirculation configuration may be used to provide containment of a plume or to allow the addition of amendments in a more controlled environment. 

NordbottenJ.M., Celia M.A., et al. Injection and storage of C02 in deep saline aquifers analytical solution for C02 plume evolution during injection. 2005 Transport Porous Media 58(3) 339-360. 

Fig. 12. Scenario for the in-situ modification of subsoils or aquifers for pollution control. The organoclay formed by injecting a solution of long-chain quaternary ammonium cations (e.g. HDTMA) acts as a sorptive zone where organic contaminants dissolved in a plume from buried waste can be immobilised and degraded. After Xu et al. (1997).

As part of geologic C02 sequestration demonstration projects conducted at the Frio Site, Liberty County, TX, USA, and the Otway Project, Nirranda South, Victoria, Australia, U-tubes were deployed for sampling multi-phase mixtures of gas, water and supercritical C02. At both these sites, C02 was injected in the subsurface to understand the subsurface movement of the C02 plume and geochemical sampling was one of many technologies employed to understand the fate of the C02. 

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