The present technology relates generally to fluid treatment systems. In particular, several embodiments are directed toward integral media treatment systems, and associated devices and methods.
Purified water is used in many applications, including the chemical, power, medical and pharmaceutical industries, as well as for human consumption. Typically, prior to use, water is treated to reduce the level of contaminants to acceptable limits. Treatment techniques include physical processes such as filtration, sedimentation, and distillation; biological processes such as slow sand filters or activated sludge; chemical processes such as flocculation and chlorination; and the use of electromagnetic radiation such as ultraviolet light. In water treatment applications, contaminants from wastewater such as storm water runoff, sediment, heavy metals, organic compounds, animal waste, and oil and grease must be sufficiently removed prior to reuse. Water purification plants and water purification systems often make use of numerous water filtration units for purification. It would be desirable to provide improved filtering units to reduce the expense and complexity of such purification systems.
The present technology is directed generally to media treatment systems for use in media-aided fluid filtration. In some embodiments, a media treatment system includes an additive source configured to inject an additive into a fluid filtration chamber for media reconditioning. In several embodiments, a controller controls the timing, concentration, and/or volume of an additive injection. An additive can be selected to achieve a desired media treatment or reconditioning outcome, such as to remove contaminants from the media and/or redirect and capture the one or more commodities separated from the media.
Specific details of several embodiments of the technology are described below with reference to
In the embodiment shown in
The system 100 can include an airlift or recirculation tube 114 that generally extends from the bottom to the top of filter chamber 108 at the center of vessel 102. An orifice 116 positioned below the recirculation tube 114 allows compressed air to be supplied to vessel 102. As depicted in
The system 100 can further include an adjustable washbox 104 can include a washbox configuration adjustment mechanism 118 for adjusting one or more parameters of the washbox as will be described below. The adjustable washbox 104 can include a water control mechanism in the form of a weir 120 and a weir control mechanism 121. The weir 120 physically blocks water above the adjustable washbox 104. The weir control mechanism 121 can adjust weir parameters, such as a height of weir 120 to control a water level 122 above the adjustable washbox 104. In other implementations, washbox configuration adjustment mechanism 118 can control the operation of weir 120 rather than having a dedicated weir control mechanism.
The adjustable washbox 104 functions to break-up any clumps of media that enter the washbox 104 and/or to further separate constituents from the media. An outlet 124 carries the separated constituents from the vessel 102 to be concentrated as a process reject, backwash, and/or a recycle stream. The system 100 also includes a water control mechanism in the form of a weir 130 for controlling outflow of filtered water via an outlet 132. Stated another way, weir 130 defines a water level 134 of the filter chamber 108 excluding the water level 122 controlled by weir 120. A head pressure or difference 136 between the washbox water level 122 and the filter chamber water level 134 causes water to flow upward from filter chamber 108 through the adjustable washbox 104. Further, in this instance, the vessel 102 includes an upper or top member 137 that seals the vessel 102 and a gas outlet 138 positioned in the top member 137. In other implementations, the vessel 102 does not include a top member and is directly open to the atmosphere. To summarize, the media bed 110 utilizes media to separate or filter constituents from the inflowing water. The adjustable washbox 104 then utilizes a relatively small percentage of the filtered water to separate the constituents from the media. The media is then recycled back to the media bed for further use.
The media treatment system 180 is configured to inject or more additives into the filtration chamber 108 and/or vessel 102 to enhance the separation of the constituents from the media. The media treatment system 180 can include an additive source 170 that stores or houses one or more additives such as solvents, dispersants, soaps, acids, bases, anti-scalants, and/or other additives suitable for separating the constituents from at least a portion of the media. The additive utilized can vary depending on the application and purpose of the fluid treatment process, type of media, and type of solids being removed or captured by the media. For example, the additive can be selected for a range of purposes including, but not limited to, recovery of oils, paraffins, organics, metals, and/or inorganic materials. In some embodiments the media treatment system 180 can include more than one additive source. Additionally, the additive source 170 can be positioned remote from, adjacent to or made integral with the vessel 102.
The additive source 170 can be coupled (e.g., via a conduit 172) to a valve 174 positioned at one or more locations at, on or within the filtration chamber 108 and/or vessel 102 (shown by an “X” in several representative locations). The valve 174 can be an orifice, a one-way valve, a sequencing valve, a manually controlled valve, an automatically controlled valve, an injector or other suitable valve. In several embodiments, the media treatment system 180 can also include a pressure difference device or pump (described below with reference to
Incorporation of the media treatment system 180 into the fluid treatment system 100 cleanses and reconditions the media by efficient removal of captured contaminants from fluid processing and/or recovery of captured commodities. The media treatment system 180 can be used for media washing to prevent fluid treatment system failure and/or as a commodity recovery system. More specifically, the system 180 can be integrated for anti-scaling and removal of precipitates from the media. This can be important to maintain the functionality of process equipment that relies on surface area and free reactive sites on the media for removal of constituents from the fluid being treated. Scaling and precipitate buildup on the media and/or equipment can increase pressure drop across the process equipment as well as fuse the media together within the media bed. For example, calcium scaling in water treatment applications can be avoided where a sand filter is the fluid treatment process for the removal of suspended and dissolved solids. The system 180 could be integrated to remove scaling continuously at a low operating setting, and/or it can be used more vigorously on a periodic schedule. In addition to contaminant capture, the media treatment system 180 can facilitate recovery of precipitated or captured solids removed from the media. For example, the solids can be a desirable commodity, as opposed to simply a contaminant or waste product. In some embodiments, the system 100 can separate the solids and dissolved constituents from the media and allow them to be concentrated in a process reject, backwash, or recycle stream through, for example, outlet 124.
In operation, contaminated water enters the vessel 102 via the inlet 106. The contaminated water then passes downward through the inlet as indicated by arrows 140 and into the manifold 112. The contaminated water exits the manifold 112 into the media bed 110 as indicated by arrow 142. As the contaminated water exits the manifold, a majority of the water flows upward (“an upflow system”) through the media bed as indicated by arrow 144 while media moves downward as indicated by arrow 146. It should be noted that the media treatment concepts described herein can be employed with a downflow system and/or other systems.
As mentioned above, each of the media has one or more free reactive sites whereby one or more of the constituents exiting the manifold 112 may become associated with or develop an affinity for the media. Constituents retained in the media bed by such an affinity are generally carried downward with the media as indicated by arrow 148. As a result, the media associated with one or more constituents (referred to herein as “associated media”) tend to sink below the manifold 112, while the unassociated media are generally located above the manifold. Accordingly, at least one media treatment system valve 174 can be positioned below the manifold 112 where there is an increased concentration of associated media so that an additive released from the valve 174 is exposed to a high concentration of associated media. For example, the valve 174 may be positioned within the media bed below the manifold 112 and/or or at any location within the vessel downstream of the manifold 112.
Compressed air supplied to the vessel 102 via the orifice 116 forms air bubbles that are less dense than the surrounding media and water. The air bubbles rise upwardly as indicated by arrow 150 and carry the media and/or constituents upwardly into and through at least a portion of the recirculation tube 114 as indicated by arrow 152. The media treatment system can have a valve 174 positioned at the base of the recirculation tube 114 that can leverage the pressure generated by the air bubbles to disperse the additive through the recirculation tube 114 and into the washbox 104. Likewise, a valve 174 can also be located at any location along the tube 114. A scouring action occurs as the air bubbles, media, and constituents travel through the recirculation tube 114. The scouring action tends to cause the constituents to be dislodged and/or separated from the media. Upon arrival at the top of the recirculation tube 114, the air bubbles tend to rise up and leave the vessel 102 through the gas outlet 138 as indicated by arrow 154. The media is relatively dense and tends to fall down around the mouth of the recirculation tube 114 and into the adjustable washbox 104 as indicated by arrow 156.
Constituents tend to be less dense than the media and as such tend to float on the water above the adjustable washbox 104. Some of the constituents may still be in some way attached to, or associated with, the media and as such tend to be carried downward with the media into the adjustable washbox 104. The adjustable washbox 104 can function to break up clumps of media and/or to separate constituents from the media. In some embodiments, a valve 174 can be located anywhere within the washbox 104 for addition of the additive to the washbox 104 to enhance the separation process. In the embodiment shown in
The timing of the sequencing can be controlled by the controller 206. For example, additive may be added to a first vessel 314a at a first time and to a second vessel 314b at a second time different than a first time. Likewise, additive may be injected to the first valve 314a and the second valve 314b at the same time. The timing can comprise a pre-set program or can be controlled in real-time (e.g., via a user interface). The controller can provide reliable, precisely-tuned equal or different distributions of additive to the individual vessels 314a-314d. The sequencing valve 310 can add the same or different volumes and/or concentrations to all or some of the vessels.
From the foregoing it will be appreciated that, although specific embodiments of the technology have been described herein for purposes of illustration, various modifications may be made without deviating from the spirit and scope of the technology. Further, certain aspects of the technology described in the context of particular embodiments may be combined or eliminated in other embodiments. Moreover, while advantages associated with certain embodiments of the technology have been described in the context of those embodiments, other embodiments may also exhibit such advantages, and not all embodiments need necessarily exhibit such advantages to fall within the scope of the technology. Accordingly, the disclosure and associated technology can encompass other embodiments not expressly shown or described herein.
Filing Document | Filing Date | Country | Kind |
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PCT/US2013/051040 | 7/18/2013 | WO | 00 |
Number | Date | Country | |
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61673181 | Jul 2012 | US |