Directional microporous diffuser and directional sparging

#There is a well-recognized need to clean-up contaminants found in ground water, i.e., aquifers and surrounding soil formations. Such aquifers and surrounding soil formations may be contaminated with various constituents including organic compounds such as, volatile hydrocarbons, including chlorinated hydrocarbons such as dichloroethene (DCE), trichloroethene (TCE), and tetrachloroethene (PCE). Other contaminates that can be present include vinyl chloride, 1,1,1 trichloroethane (TCA), dichloroethane (DCA), 1,4 dioxane, and very soluble gasoline additives such as methyl tertiary butyl ether (MTBE). Other contaminants may also be encountered.

#Often such contaminants are found in areas that are inaccessible, e.g. under parking lots, road beds buildings, airport runways, high-use highways, and the like where sparging techniques that require drilling of wells or driving of microporous diffusers directly into soils, close to or underneath such road beds, parking lots, buildings and the like may be impractical because of the large number of penetrations through reinforced concrete or surfaces sensitive to loading or proximity to heavily traveled or used area.

#According to an aspect of this invention, a method includes emitting plural streams of a fluid into a soil formation with the streams having different radii of influences in different directions.

#FIGS. 1A and 1B are cross-sectional views showing sparging treatment examples.

#FIG. 2 is a diagrammatical view showing a multi-sparging apparatus installation.

#FIGS. 3A-3E are diagrams depicting details of a directional diffuser in the example shown in FIGS. 1A or 1B.

#Referring now to FIG. 1A, a sparging arrangement 10 for treating plumes, sources, deposits or occurrences of contaminants, is shown. The arrangement 10 is disposed in a well 12 that has a casing 14 with screen 14 a. The casing 14 supports the ground about the well 12. Disposed through the casing 14 are one or more directional microporous diffusers 50, 70 (discussed in FIGS. 3A-3C or 4A-4C).

#The arrangement 10 also includes a first air compressor/pump 22 and a compressor/pump control mechanism 27 to feed a first fluid, e.g., air into a two port mixing valve 23 and a second pump 26 and coupled to a second source, e.g., an ozone generator 28 to feed ozone (O3) to the mixing valve 23. Other arrangements are possible.

#The mixing valve 23 is coupled via a check valve 25 to an inlet port of a solenoid-controlled valve 30. Solenoid-controlled valve 30, as shown in FIG. 4, has a common inlet port 31 and here four branch or outlet ports 32a-32d. A control arrangement 35 controls the solenoid-controlled valve 30. The control arrangement 35 can be a series of switches to actuate the solenoids, via lines 35a, or could be more complicated schemes. The gas mixture from the central mixing valve 23 is distributable to each of the outlet ports 32a-32d of the solenoid-controlled valve 30.