Water Purification Process with Water Pretreatment

Abstract

A water purification process for treating water containing at least some organic contaminants, and including the steps of pre-treating the water for capturing organic contaminants from solution in a water stream, by passing the water into a spin up bowl to speed up the water stream, forcing the high speed stream through an annular flow passage located centrally of the spin up bowl passing the high velocity stream between a magnetic member and a magnetic ring, thereafter passing the water stream into an energy recovery bowl, directing the flow from the flow passage onto a zinc anode member; and thereafter passing the water stream along a grounded pipe, thereby causing the development of fine particles of calcium carbonates, and capturing the organic contaminants

Claims

1-5. (canceled)

6. A process for removing precipitates from a water source containing calcium bicarbonate (Ca(HCO.sub.3).sub.2) and organic contaminants, wherein the calcium bicarbonate exists in the water source as Ca.sup.2+ ions, HCO.sub.3.sup.− ions and an initial concentration of CO.sub.3.sup.+2 ions, said process comprising the following steps of: (i) passing the water source at a first predetermined speed into an input chamber (40); (ii) optionally creating a vortex of the water source to accelerate the water source's speed; (iii) establishing a magnetic field across a passageway (56, 64) from the input chamber to an output chamber (90) comprising an electron source (102), wherein a product of the magnetic field and the water source's speed is in excess of 36,000 gauss.Math.ft/sec, thereby stripping H.sup.+ ions from HCO.sub.3.sup.− ions to form an additional amount of CO.sub.3.sup.−2 ions in excess of said initial concentration of CO.sub.3.sup.−2 ions in the water source; (iv) adding electrons from the electron source (102) to the water source, wherein CO.sub.3.sup.−2 ions and Ca.sup.2+ ions form insoluble calcium carbonate (CaCO.sub.3) precipitates that incorporate an organic contaminant, wherein the electrons protect the calcium carbonate nucleation sites; (v) passing the water source through a grounded electrically conductive body (22) to provide additional nucleation sites; and (vi) removing said insoluble calcium carbonate precipitates with the organic contaminant from the water source.

7. The method of claim 6 further comprising the step (v) passing the water source to a reverse osmosis filtration unit to filter the water source.

8. The method of claim 6, wherein the electrically conductive body is connected to the electron source.

9. The method of claim 6, wherein the passageway is a variable gap formed between a first surface and a second surface, and wherein a distance between the variable gap changes to change the speed of the water source and the strength of the magnetic field.

10. The method of claim 9, wherein as the distance between the variable gap decreases, the strength of the magnetic field and the speed of the water source increase.

11. The method of claim 6, wherein step (ii) occurs and the input chamber is substantially circular and the vortex is created by tangentially introducing the water source at a periphery of the input chamber and locating the passageway proximate to a center of the input chamber.

12. The method of claim 6 further comprising the step of settling out larger particles from the water source before step (i).

13. The method of claim 6, wherein in step (i) the water source is pumped into the input chamber.

14. The method of claim 6, wherein in step (iii) the product of the magnetic field and the water source's speed is as high as 120,000 gauss.Math.ft/sec.

15. The method of claim 6, wherein the electron source comprises zinc or aluminum.

Description

IN THE DRAWINGS

[0029] FIG. 1 is a schematic block diagram illustrating the process of the invention;

[0030] FIG. 2 is a transverse section of the pretreatment apparatus;

[0031] FIG. 3 is a section along line 3-3 of FIG. 2; and

[0032] FIG. 4 is reproduction of FIG. 2 from Chave & Suess, Limmology & Oceanography, Vol. 15, Issue 4, p. 636.

DESCRIPTION OF A SPECIFIC EMBODIMENT

[0033] As already outlined above, the invention relates to the a process for the modification of raw water which incorporates both inorganic contaminants and organic contaminants, in which the organic contaminants are of the type which can be sidelined by cloaking them within calcium carbonate particles. Such raw water typically is sea water, but is obviously not exclusive to sea water but is applicable to any raw waters which require purification for consumption, or improvement for use in any industrial process.

[0034] In general, a water purification process of this type takes place in a series of separate steps by means of a plurality of components, (FIG. 1) In particular typical components comprise an intake (10) typically being a pipe immersed in a source of water. In many cases such a pipe will extend a considerable distance off shore, so as to be drawing in cleaner water, than is available along the shore. Water is than passed through a coarse screen (12) which is a barrier to remove components in the water or indeed live creatures namely fish, shells, and also seaweed and large pollutant material. The water is then passed to a sediment basin (14), settling out silt.

[0035] From the sediment basin, where the water is essentially still, for at least a certain period of time, a water pump (16) pumps the water to a fine screen (18). The fine screen typically removes any material which will not settle readily out from the water in the settlement basin. This may include for example, plankton. The water is then passed directly to a pre-conditioning unit (20), the details of which will be described below. The process of passing through the pre-conditioner (20) is to create a temporary production of calcium carbonate particles, by breaking up the bicarbonate ions present in the water, and then allowing the calcium carbonate particles to crystallize and absorb organic pollutants, in a manner described below.

[0036] From the pre-conditioner (20) water containing both inorganic components and also calcium carbonate particles with absorbed organic material, passes through an electrically grounded pipe (22). The effect of passing the water through the grounded pipe is to assist in a more complete creation of carbonate crystal scales. The water then passes to a high pressure pump (24) which creates a high pressure and forces the water into a reverse osmosis separator unit (26). Waste water containing the inorganic material and the calcium carbonate micro-particles is rejected from the upstream side of the reverse osmosis unit and is passed to waste (28). Water passing through the membrane, to the downstream side will be delivered to a storage tank (30). Water is then distributed as required.

[0037] This is a general description of the process of the invention. The rejection of the inorganic material and the created calcium carbonate particles with absorbed organic solutes takes place in the reverse osmosis unit itself. Such material is rejected continuously from the unit, along with surplus water which is a fraction of the water passed into the unit. Reverse osmosis systems avoid the inefficiencies of passing one hundred percent of the water itself through the purification membranes.

[0038] Therefore there is always a volume of waste water, in which the inorganic material and calcium carbonate particles are entrained and are rejected back to the raw water source.

[0039] It will be appreciated that this process does not increase the pollution of the raw water source, since the only material being returned to the raw water source is material which was extracted from it in the first place.

[0040] In accordance with the invention, the pre-treatment unit (20) and its operation are now described in more detail.

[0041] Referring now to FIGS. 2 and 3 it will be seen that the pre-treatment unit (20), comprises in this embodiment, an angular momentum spin-up input bowl (40), of circular shape and defining a generally arcuate outer perimeter wall (42), and an upper planar wall (44) and a lower wall (46). A water inlet (48) is positioned, more or less tangentially to the outer perimeter wall at its point of maximum circumference.

[0042] The inlet (48) delivers incoming water tangentially around the arcuate perimeter wall (42) of the spin up bowl.

[0043] The lower wall (46) defines a central outlet opening (50). Around the central outlet opening (50) there is provided an annular magnetic ring (52) formed of ultra magnetic alloy. The annular ring (52) is secured in the opening by means such as screws (54). The annular ring (52) defines generally angled side walls (56), defining a circular opening, of progressively narrowing dimension, from top to bottom. A complimentary magnetic plug member (58) is formed of intense ultra magnetic alloy. The plug (58) is mounted on a movable spindle (60), which is adjustable vertically, thereby enabling the plug (58) to be moved towards or away from the ring (52). The plug (58) defines generally angular side walls (64), formed at angles complimentary to the angular side wall (56) of the ring (52). Ring (52) and member (58) can also be formed with protective corrosion resistant coatings containing magnetic minerals. Magnetite would be particularly suitable.

[0044] In this way, a central outlet passageway of annular shape is provided which narrows progressively from the top of ring (52) to the bottom of ring (52). The width of the annular opening may be adjusted by moving the spindle (60).

[0045] In order to support the spindle (60) there is provided an access plate (68), secured to an opening (70) in the upper wall (44) by screws (72). A vertical guide sleeve (74) extends from plate (68) and the spindle (60) is located in the sleeve (74), being sealed by O-ring seals (78).

[0046] At the upper end of sleeve (74), there is an internally threaded nut (78), secured to the top of the sleeve (74). The spindle (60) is threaded with complimentary male threads (80). A manually operated cap (82) which may or may not have an additional operating arm attached (not shown) is secured to the top end of spindle (60).

[0047] An adjustment scale (84) is formed on the exterior of sleeve (74).

[0048] By rotating the cap (82), the spindle (60) can be moved downwardly or upwardly as desired. In this way the dimensions of the gap between the ring (52) and the plug (58) can be adjusted along an externally calibrated scale.

[0049] The pre-treatment unit (20) further comprises a kinetic energy recovery bowl (90), located beneath the spin-up bowl (40). While the two bowls are respectively shown as upper and lower in the illustration, it will be appreciated that this is without limitation. The arrangement of the spin-up bowl and the recovery bowl may be varied depending on circumstances.

[0050] The recovery bowl (90) is seen to comprise a generally circular chamber defined by an arcuate side wall (92), and an upper planar wall (94) and a lower planar wall (96). An outlet opening (98) is provided, more or less tangential to the arcuate side wall and will be connected down stream to the next piece of equipment, namely the grounded pipe (22).

[0051] The kinetic energy recovery bowl (90) defines an inlet opening at the center of annular ring (52) in its upper wall (94). The annular ring (52) in the spin-up bowl is of sufficient thickness that it extends down through the inlet opening in the upper wall of the recovery bowl (90). Thus the lower end of the opening defined by the annular ring passes water directly to the recovery bowl (90). Directly opposite to such annular ring, an anode block (102) is secured to lower wall (98) of the recovery bowl (90). The anode block (102) is preferably formed of zinc or aluminum metal. It is secured in place by means of bolts (104) passing through lower wall (96) and the bolts (104) are provided with O-rings (108), so as to protect the connection between the anode block (102) and the lower wall (96). The function of the anode block is to receive the direct impact of water flowing through the annular ring (52) and to provide a source of electrons for protecting calcium carbonate nucleation sites generating particles off of local plumbing while temporary super-saturation of the treated water with said mineral still prevails.

[0052] Within the recovery bowl (90) the water will then spin in an outward spiral until it reaches the arcuate side wall (92), and will then exit through the outlet (98).

[0053] In order to provide a secure integral construction, external upper and under junction flanges (108) (110) are provided on the respective spin-up bowl and recovery bowl, and they are united together by fastening such as bolts (112).

[0054] The function of the pre-treatment unit (20) will thus become more readily understood. Water containing both inorganic contaminants, and organic contaminants, and calcium bicarbonates, will enter the spin-up bowl (40) tangentially through the inlet (48), and will spin around in a spiral fashion, of ever decreasing diameter, until it exits through the central opening defined by the annular ring (52). Depending upon the adjustment position of the plug (58), the water will flow at a greater or lesser velocity, but will have accumulated considerable speed and energy during its rotation. Water flow rate is determined by the system pump, whereas the velocity through the magnetic gap for passing said flow is the factor set by the gap to interact with the magnetic field. As water passes through the magnetic gap between the ring (52) and the plug (58), the calcium bicarbonate molecules are temporarily broken apart so as to provide a source of temporary calcium carbonate molecules, and free hydrogen ions. As the water containing the temporary separated molecules impacts on the anode block (102), the calcium carbonate will be combining with the organic contaminants in the water and depositing out as crystals. The high velocity of the water flow will however break up the formation of fragile “frost-like” adhering crystals so that the water will acquire a suspension of crystalline fragments or particles.

[0055] The high velocity of the water exiting the ring (52) and impacting on the anode block (102) will be largely recovered as energy in the outwardly flowing water in the recovery bowl, which then exits through the outlet (98). Water exiting through the outlet (98) will contain a proportionate size of crystalline calcium carbonate particles, incorporating organic contaminants.

[0056] This water is then passed through the grounded pipe plumbing unit (22) which further assists in the formation of crystalline calcium carbonate combined with organic contaminants by providing additional nucleating surfaces while the exit water still retains some supersaturation—(typically up to about 3 seconds before return to a pH-controlled equilibrium). The maintaining of nucleating sites beyond the unit itself, thus, enhances the amount of scale pedicles that can be formed for absorbing troublesome organics. As treated water flows faster along the midline of the exit pipe, this zone identifies as the most freshly treated and hence the most supersaturated for growing crystal deposits. The result is that nucleating material grows fastest at the expanding tips of such deposits in fragile “frost-like” structures rather subject to breaking off by flow pressure to create said particles. Particles typically in the range of 70 to 150 microns have been observed by government laboratories.

[0057] The plumbing unit (22) generates additional crystalline calcium carbonate deposits while the “conditioned water” still retains much of its temporary calcium carbonate super saturation. Typically, some 10 to 15 feet long, plumbing unit (22) has pipe wall surfaces, which under appropriate conditions, acquire and retain calcium carbonate scale sites for sustaining the nucleation of further scale dendrites that break off as extra organic-scavenging particles.

[0058] To insure that such nucleating sites are retained against being redissolvecd by stray positive and AC voltages in the plumbing unit (22), particularly during non-flow periods, it is advantageous for the pipe to be of a single conductive metal, preferably iron, electrically connected as at (114) to the sacrificial zinc anode block (102), inside the bowl (90) itself.

[0059] The electrons available from the zincs higher corrodability, protect carbonate deposit sites from the acid attack of ambient hydrogen ions (W). The extra negatively-charged electrons (e−) from zinc block (102), aid in neutralizing such hydrogen ions into free hydrogen gas (H.sub.2) before carbonates (CO.sub.3.sup.−) can be converted back to soluble bicarbonates (HCO.sub.3.sup.−).

[0060] Simple chemical equations such as:

2H.sup.++2e.sup.−.fwdarw.H.sub.2 and CO.sub.3.sup.−+H.sup.+.fwdarw.HCO.sub.3.sup.− (soluble)

[0061] may apply with the latter reaction being avoided by the electrons from the zinc block (102). Another problem arises from stray AC voltages from ubiquitous AC motors and related units which can cause electrolysis of sufficient potential across water-to-pipeline interfaces which “electro-clean” pipeline surfaces of their useful carbonate sites. For this reason, plumbing unit (22) is additionally grounded to earth, at (116), to snort out such potential voltages.

[0062] These two features assist in maximizing the quantity of absorptive carbonate particles generated directly and thus minimizes the quantity of troublesome uncaptured organic material which would otherwise foul RO membranes.

[0063] Any remaining calcium carbonate, which has not attracted the organic material, ultimately recombines with the hydrogen ions to become re-solubilized as calcium bicarbonate.

[0064] This water is then passed via pump (24), to the reverse osmosis unit (26). In this unit, the fine calcium carbonate crystalline particles will remain on the upstream side of the reverse osmosis membrane (not shown). Water molecules will pass through the membrane and constitute the purified water outlet sent to tank (30). Water which does not pass through the membrane will flow continuously out to waste (28). This water containing inorganic contaminants will entrain the majority of the calcium carbonate crystalline particles, thus maintaining the membrane as far as possible free of contaminants and membrane-blocking components. This will substantially increase regular product flow and the useful productive life of the membranes.

[0065] The waste water containing such crystalline calcium carbonate will then be returned to the original source.

[0066] Typical operating parameters are as follows.

[0067] The magnetic gap is determined by the ion separation force equation F=Bvq, where

[0068] B is the magnetic field in gauss, v is the water velocity in feet per second.

[0069] Generally ion separation force should be in the range 18,000×q and 120,000×q, or the magnetic field×water velocity should between in the range of 18,000 gauss.Math.ft/sec to 120,000 gauss.Math.ft/sec.

[0070] Preferably the range will be at least around 38,000 gauss.Math.ft/sec and upwards, which has proved satisfactory in typical cases.

[0071] The range of the magnetic gap will be somewhere between 1/16 inch and ¼ inch for most water flows and magnetic materials. Stronger magnets may enable a somewhat increased gap, permitting higher flow rates of source water through the gap.

[0072] For example using a 4 inch diameter water supply pipe a water flow volume of 220,000 US gpd for desalination of the source water, the water velocity can be increased, in the spin up bowl by between about 4 and 5 times. At this speed commercial strength magnets as available today would provide adequate treatment.

[0073] Quite consistently, all dissolved ion pairs when bound together solely by electrostatic charge are pulled apart, when the Lorentz Forces of F=Bvq become a sufficient electric force (F). In electroplating technology, the electrodes adding or subtracting electrons makes such separations permanent; but, in absence of electron deliveries, most ions will snap back together within microseconds upon exiting the magnetic field. With some ions such as those of hydrogen returning back to their carbonate partners, however, the reunion occurs at a very delayed pace for restoring original bicarbonates.

[0074] Raw source water, including well water, municipal water, sea water, stream and river water typically contain dissolved calcium bicarbonate (Ca(HCO.sub.3).sub.2). It is well known that calcium carbonate exists as ions in water including Ca.sup.2+ ions, HCO.sub.3.sup.− ions and CO.sub.3.sup.−2 ions, depending on the pH level of the source water.

[0075] Focusing on magnetic field effects upon the bicarbonates in seawater [typically Ca.sup.++ @411 mg/l & HCO.sub.3.sup.− @145 mg/L], three significant separations occur during seawater transit in the magnet field, namely:

[0076] 1) Bicarbonate break-ups by passage through the magnetic field:

##STR00001##

[0077] Because both magnet field strength and local water velocities will vary across the magnetic gap, Equation A also occurs as well where calcium bonding to carbonate includes extra non-polar bonding that resists ion separation and even regular carbonate solubility.

[0078] 2) The separated ions of Equations A, B, and C upon exit from the magnetic field recombine at differing rates as depicted below:

##STR00002##

[0079] As would be normal for most soluble ions, Equation D depicts the rapid pairing of doubly charged calcium and carbonate ions to contribute to the calcium carbonate formed by Equation A.

[0080] Equation E depicts a very different slow return of hydrogen ion to any available carbonates whose symmetrical hydrated form, C(OH).sub.6.sup.− [from CO.sub.3.sup.−+3H.sub.2O] finds no open vacancy for the returning hydrogen until a basic structural rearrangement restores a “parking space” for the ion.

[0081] Ultimately, a seawater containing a near saturation level of about 0.25 mg/L of carbonate [CO.sub.3.sup.−] (i.e. pH 7.8) would have its freed carbonate soar to the range of 100 mg/L or more via magnetic passage breakdown of much of the 145 mg/L of bicarbonate (via Equations A, B, and C). Then, the aftermath of the magnet field separations features a faster capture (Equations D and E) of the liberated carbonate ions by the calcium ions over the hydrogen ions. And, once the calcium carbonate forms up into assembled crystals, as aided by surface nucleation sites, the return to the original bicarbonate solubility of the solids, now in scale particle form, becomes even much further delayed.

[0082] Industrial and commercial experiences with scale precipitation from both fresh and seawater sources being used in cooling and boiler make-up operations have shown that magnetic treatment does not just work merely to prevent carbonate scaling; but, it also prevents biofouling and most of its associated corrosion. Scale deposited or corrodable surfaces invariably contains organic matter concentrated for a greater availability for the growth of microorganisms.

[0083] When carbonate scale is deposited on equipment surfaces its content of absorbed organic nutrients accumulates with it. But when scale minerals are forced out of solution in the form of buoyant carbonate particles, not only is scale prevented from depositing upon working surfaces, but the most troublesome organic nutrients are also being stripped from solution into these particles away from said surfaces. The liquid water phase around said particles no longer contains mineral or organic saturations to foster harmful deposits.

[0084] Though literally thousands of reviewed studies and papers are on record showing organic contaminants captured using inorganic flocculants, calcium carbonate is cited as one of the most effective. Notably, inorganic solids precipitating out water need to contain extra non-polar bonds as well that also prove attractive to non-polar organic matter to join them. In the case of natural seawater organics, an article by Keith E. Chave & Erwin Suess, “Calcium Carbonate Saturation in Seawater: Effects of Dissolved Organic Matter”, Limnology and Oceanography, Vol. 15, Issue 4, pp. 633-637 (1970) illustrated how the natural organic mailer from open ocean and from a seawater aquarium were absorbed and even so avidly on calcium carbonate precipitates that it actually delayed its final flocculation. [With magnetic treatment not requiring a flocculation step, our magnetic device encounters no such delays.] FIG. 2 from that article, reproduced as FIG. 4, shows their results.

[0085] The reality of particles between 70 and 150 microns in size being formed by magnetic field treatment was quite confirmed by particle count testing in 1992 at Ortech, the Ontario government lab, with support from the Canadian Federal NSERC (National Science and Engineering Research Council) agency. Results were repeated when over 240 mg/L (70%) of the test well water's 343 mg/L calcium hardness was noted to have been forced to precipitate into these organic-absorbing particles. At an average of 100 microns, these particles rank one to ten million (10.sup.6 to 10.sup.7) times the 0.01 to 0.1 nanometer size pore sizes of RO membranes. Though buoyant in the treated feed wafer, these comparatively “mountain-sized” particles and such denatured organic debris that might be released from them can no longer invade membrane orifices to permanently seal them.