CA1071577A - Galvanic flow system for joint particulate recovery and liquid purification - Google Patents
Galvanic flow system for joint particulate recovery and liquid purificationInfo
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- CA1071577A CA1071577A CA257,306A CA257306A CA1071577A CA 1071577 A CA1071577 A CA 1071577A CA 257306 A CA257306 A CA 257306A CA 1071577 A CA1071577 A CA 1071577A
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Abstract
ABSTRACT OF THE DISCLOSURE
Solid and/or dissolved contaminants are separated from a polar liquid such as water by providing in the contaminated, acidic liquid medium a galvanically charged particulate dispersion of defined size, concentration, density and free surface energy, and then flowing such loaded medium through successive oxidation and treatment zones of an electrically insulated apparatus at a rate defined by dimensionless parameters such as Reynolds numbers, etc., so as to prevent phase separation. Gaseous oxygen adheres to particle surfaces and oxidation is further promoted by bringing medium to pH 2.0 to 2.5 as with sulfur dioxide gas, plus exposure to action of heavy-metal ions such as ferrous/ferric. After air blowing, medium is neutralized and brought to pH 10-11 with continuous aeration of suspended flocculant, then treated with soda ash and optionally additional particulate (recycled sludge), and the contaminant matter then allowed to precipitate with concurrent galvanic grounding of the medium. The dispersed particulate matter may be inert and deliberatly added (e.g., shredded cellulose) or it may be produced In situ by fractionation of component debris as in sewage-refuse; when possible, as in the latter case, the particle itself is subse-quently oxidized. In either event, dual end products are potable water and sterile sludge. Dissolved salts such as sodium chloride are simultaneously removed from, medium as component of sludge; applicable to remove toxic components from cooling water systems, recover traces of precious metals, etc., from slurry or run-off liquid, brackish water, industrial waste, etc.
Suitable treating apparatus is also provided.
Solid and/or dissolved contaminants are separated from a polar liquid such as water by providing in the contaminated, acidic liquid medium a galvanically charged particulate dispersion of defined size, concentration, density and free surface energy, and then flowing such loaded medium through successive oxidation and treatment zones of an electrically insulated apparatus at a rate defined by dimensionless parameters such as Reynolds numbers, etc., so as to prevent phase separation. Gaseous oxygen adheres to particle surfaces and oxidation is further promoted by bringing medium to pH 2.0 to 2.5 as with sulfur dioxide gas, plus exposure to action of heavy-metal ions such as ferrous/ferric. After air blowing, medium is neutralized and brought to pH 10-11 with continuous aeration of suspended flocculant, then treated with soda ash and optionally additional particulate (recycled sludge), and the contaminant matter then allowed to precipitate with concurrent galvanic grounding of the medium. The dispersed particulate matter may be inert and deliberatly added (e.g., shredded cellulose) or it may be produced In situ by fractionation of component debris as in sewage-refuse; when possible, as in the latter case, the particle itself is subse-quently oxidized. In either event, dual end products are potable water and sterile sludge. Dissolved salts such as sodium chloride are simultaneously removed from, medium as component of sludge; applicable to remove toxic components from cooling water systems, recover traces of precious metals, etc., from slurry or run-off liquid, brackish water, industrial waste, etc.
Suitable treating apparatus is also provided.
Description
7~577 B~ CKGR OUND OF THE INV:~ N~ ION:
The demand for water purification does not arise solely from the need for treating sewage or noxious industrial waste, nor is it necessar-ily directed merely toward obtaining potable water for humans and animals.
Recent environment control regulations have restrained the discard of water such as that w~ ',through ordinary industrial use has appreciably increased its content of dissolved solids (which are generally inorganic or mineral compounds) as well as inhibiting discard of such liquid which has accumulated or concentrated particular toxic components.
For example, the body of water which is circulated as a coolant in 10 many industrial or chemical plants, is then returned to a heat exchanger where part of it is evaporated in order to reduce the temperature of the remainder, which remainder is then recirculatedO This evaporation step itself would increase the concentration of contained solids merely by re ducing the volume of liquid. However, in its travel, the liquid picks up deposits or sediment from the plumbing system, and in addition, in order to minimize corrosion, foaming and scale formation (such as resulting from "hard water "), various inhibitory additive s are mixed into the cir -culating stream. These obviously contribute further to the dissolved solid content and after the latter has built up to the maximum allowable for 20 continued circulation, it becomes necessary to discard part of the fluid mixture and replace it with fresh water (and new additives).
However, this heavily loaded discard has now become an illegal pollutant when released into flowing streams or ocean. The problem is to purify it before release; and hopefully if such purification process is suf-ficiently successful or complete, the water may be reused indefinitely and need not be released at all.
~ particular contaminant in such cooling water system is chromium which is a component of many anti-corrosive or biocide additives.
The demand for water purification does not arise solely from the need for treating sewage or noxious industrial waste, nor is it necessar-ily directed merely toward obtaining potable water for humans and animals.
Recent environment control regulations have restrained the discard of water such as that w~ ',through ordinary industrial use has appreciably increased its content of dissolved solids (which are generally inorganic or mineral compounds) as well as inhibiting discard of such liquid which has accumulated or concentrated particular toxic components.
For example, the body of water which is circulated as a coolant in 10 many industrial or chemical plants, is then returned to a heat exchanger where part of it is evaporated in order to reduce the temperature of the remainder, which remainder is then recirculatedO This evaporation step itself would increase the concentration of contained solids merely by re ducing the volume of liquid. However, in its travel, the liquid picks up deposits or sediment from the plumbing system, and in addition, in order to minimize corrosion, foaming and scale formation (such as resulting from "hard water "), various inhibitory additive s are mixed into the cir -culating stream. These obviously contribute further to the dissolved solid content and after the latter has built up to the maximum allowable for 20 continued circulation, it becomes necessary to discard part of the fluid mixture and replace it with fresh water (and new additives).
However, this heavily loaded discard has now become an illegal pollutant when released into flowing streams or ocean. The problem is to purify it before release; and hopefully if such purification process is suf-ficiently successful or complete, the water may be reused indefinitely and need not be released at all.
~ particular contaminant in such cooling water system is chromium which is a component of many anti-corrosive or biocide additives.
-2- ~S
1~D7~577 rrhUs hexavalant chromium is a toxic substance not releasable ~to the environrnent, Other toxic components of common cooling water additives are cyanides and phosphates, which must be detoxified before release.
Purification of polluted water for purposes of reuse, whether start-ing with agriculture /municipal sewage or with industrial waste, has been concerned primarily with recovery of potable water, only after the initial separation and disposal of solid components in an inert state, this being considered a necessary and preliminary step for any subsequent treatment.
~he solids may have then been utilized to a small extent as plant support 10 base or land fill, but such product is not a primary purpose for effecting the separation and for the most part the undifferentiated sludge is simply separated in bulk and discarded in the manner most convenient. Purifica-tion of the aqueous phase then takes place (if at all) as a successive, rather than concurrent, procedure. However, it will be rea-lized that the aqueous run-off from many and probably most water-treating procedures, (even if only involving flushing) carries a quantity of solid and potentially-solid ingredients having tangible economic value if such could only be re-covered in concentrated form without great expense.
Further, treatment of such masses of contaminated water in the past 20 has been primarily on a batch basis; large bodies of water being treated with acid or other reagent in a "settling basin" or even in successive chambers and chen allowed to stand for a prolonged period until spot checks show that the supernatent was clarified. In brief, it has not been realized that by careful regulation of the parameters of a flowing stream containing charged particles, separation/purification of an impure squeous medium could be effected in a fraction of the previous time, and also that the controls could be shifted so as to maximize the withdrawal of specific contaminants which it was desired to concentrate in the solid stateO Some ~L~7~57 ~
substances it may be desired to destroy -- as microorganisms, herbi-cides, pesticides and inorganic toxins -- or to recover, such as nitro-genous compounds, precious metals, etcL. Accordingly, the control para-meters of such flow treatment can now be accommodatad to a particular feed stock and with a view as to how it is wished to dispose of specific c ontaminants .
It has long beeD known to plarify waste wate r by oxidizing it in the joint presence of iron plus sulfur dioxide or an o~idizing a~ The im-purity is then removed by flocculating the iron in alkaline media. How-eve r, 'to the extent ~hat this process has been used, bulk solids necessar-ily were first removed as by filtration, and as to the remaining filtrate, past treatment does not remove dissolved impurities Isuch as inorganic salts typified by NaCl) or substances incapable of oxidation (such as metal particles): each of chese classes may include such undesirable toxins as arsenic, mercury, cadmium, lead, selenium, boron, etc.
SUMMARY OF TE~E INVENTION:
It has now been found that this dual oxidation/precipitation step can be incorporated into a composite treating process whereby essentially any flowable, polar liquid medium containing (:Einely fractionated) waste/refuse, as well as soluble salts and non-oxidizable impurities, can have all non-gaseous impurities removed as solids, leaving a sterile, pure, oxygen-containing liquid (e. g., potable water, which is also capable of supporting fish and other marine life). The precipitated material is also sterile and if desired can be further fractionated to recover substances of economic value, such as precious metals, fertilizer-enriched sludge, etcO
In brief, in a primary reaction vessel or multi-unit apparatus, all of which is electrically insulated, there is provided (in the absence of any ~7~5~
externally imposed electric current) a self-generated galvanic cell formed by "soluble" or free electrons resulting from acidic oxidation of a contain-ed heavy metal capable of alkaline flocculation, suc:h as iron and/or aluminum, as well as by free electrons produced by disassociation of water (or other polar media) by introduction of sulfur dioxide, A minimum suspension of minute particles (as hereafter definedj is also deliberately provided, ither by addition or by f ractionation of bulk solids initially presentO Such dispersed particles (preferably constituting all of the solid material present except for the electron-producing metal) inherently possess 10 random movement in the liquid medium (which movement is the Van der Waals effect resulting from an internally generated spin of an unsymmet-rical molecule). In conjunction with the moving electrons, this results in a distribution of charge to other particles and adhesion between charged microparticles and minute gas bubbles, which ultimately results in co~n-plete oxidation of all oxidizable material present. ~his necessary cross-distribution or random mixing of electrons with both charged and uncharged particles in the insulated cell may be accentuated by bubbling gaseous oxygen (air) and/or sulfur dioxide through the liquid, as well as by agi-tation of the body of liquid as by means of pump or stirrer. Electrical 20 insulation of each reaction vessel is necessary in order to keep such charge (maintained by pH regulation) from grounding through a conductive reaction vessel or flow conduit.
Under the step-wise oxidizing conditions and imposed galvanic flow pattern, metallic ions agglutinate with particulate matter and are replaced in the aqueous medium by other cations, i.eO ,hydrogen ions, at the same time maintaining the selected concentration of acidity. Among other reac-tions, part of such hydrogen ions couple with available nitrogen to form cJJ ~I ~Such ammonium ion then couples with ferrous ion to form (green) ferrous ammonium ion.
~ ~7~.S77 Successive cher~lical reaction steps can be effected by batch proce-dure, as long as sufficient agitation is provided to keep the ingredients from settling out prior to the ultimate and de sired flocculation. However, it is usually desirable to effect the process as a continuous flow, particu-larly when a continuing supply of feed stock is available, as from a muni-cipal sewage collection stream or similar industrial/agriculture waste flow.
Accordingly both the liquid medium and an associated gas stream are moved to and through successive treating zones or chambers. Ihe body of reactant gas (which should include oxygen) is channeled to contactingly e 10 overlie or flow through t~ lisLuid medium as the case may be.
Accordingly, by relating the size and shape of the reaction vessels and connecting conduits, a series of dimensionless parameters has been obtained for both the liquid and gas streams, by use of which controlled flow rates the material being treated is moved in a substantially contin-uous but step-wise pattern of reaction which prevents phase-separation while enabling or promoting electron clistribution until complete oxidation is effected. ~he final chemical-treatment step is then accomplished by ~JK~ 0~
all~i~ of the medium with avoidance of potential phase-separation during a preliminary digestion period followed by electrical grounding of 20 the medium concurrent with joint precipitation/flocculation of the metallic ions and the coagulated impurities. In addition, such grounding of the medium, which may be effectuated by grounding the insulated reaction vessel containing it, produces a noticeably more firmly-packed precipi-tate than would otherwise result.
When the composite impurity is composed of both (a) cellulosic material (eO g. ,food residues, waste paper or cartons, etc. ) and (b) sus-pended minerals or metals and/or soluble salts (e.g.,brackish water) the final alkaline flocculation tends to segregate "a" and "b" into successive layers with the "b" material being precipitated first or underneath the "al' ~- ~07~577 material. ~he procedure can thus be used to concentrate small quantities of precious metals from slurries and the like; in the event that "a"
material is not already mixed with it, the minimum charged particulate matter is added as described.
Separation of all potentially-solid components from such a flowing galvanic cell, by groundin~g and cessation of movement or agitation, in addition to re~noving in the flocculate such impurities as might previously be expected from the chemical reaction alone, now also draws soluble salts such as sodium chloride out of solution as well as precipitating sus-10 pended non-oxidizable particles. The only requirements for participating substances are that the liquid be a polar liquid, ancl the ~lid or potentially-solid substarlce be capable of the Van der Waals effectO In addition to water, other polar liquids are alcohols, acids, bases and other substances which ioniz;e or conduct an electric current. ~he dispersed particulate matter should constitute a minimum of about 0.1% w. and have a particle density of about 1. 05 to about 2. 0 and a1~e of about 30 to about 225 microns with free surface energy of about 100 to about 500 ergs/cmZ.
In this conne ction it will be realized that the smaller the particle size, the greater the relative surface area and the greater the forces of 20 surface attraction (relative to weight), so that the relative influence of gravity on the particle is correspondingly diminished. T hus the specific surface energy of a given solid can multiply more than 8000 times in going from approximately two inch di~eter to one micron. Its unit sur-face energy at the same time increases more than 600%. Accordingly, the greater the fractionation (maceration) of the bulk material into small par-ticles, the greater effect the increased surface energy will have on reaction and flow properties. Ihis factor is the same of course whether ~he material constitutes matter which (in addition to its carrier f~mction) is to be oxi-dized, or whether it is particulate matter added merely for its function of 30 carrying a charge in the flowing galvanic stream.
7~LSi77 However it will be apparent also that such fractionated particles, possessing Brownian movement and increased unit surface energy, have a strong tendency to coalesce if brought together; that is, they become a non-free-flowing mass rather than acting as independent discrete particles.
Such potential coagulation is prevented by (1~ pump action, mechanical agitation, and passage of gas currents through the liquid, each applied at a particular critical location, and (2) by moving the galvanic flow stream at a varied and deliberate rate in accordance with Reynolds Numbers and other dimensionless parameters selected to prevent phase separation. Thus 10 when later such suspended particles (galvanically charged) are finally di-rected to settle out, in cooperation with a flocculating ion, cancellation or grounding of the galvanic charge tremenduously reinforces this final (de-sired) phase separationO Thus one particularly notable and totally unexpec-ted result from this flowing galvanic cell and from the ~an der Waals sur-face effect exhibited by the particulate dispersion, is that by the present process soluble salts (in particular NaCl or other alkali halides) present in the liquid, also leave their state of solution and enter into the separat-ing flocculateO Such desalinification may be explained in part by continu-ation of the suspended flocculate in an oxygen-saturated medium until the 20 reduced flocculating ion (ferrous) is itself completely oxidized (to ferric ion).
To restate the present process: flowable contaminants of a liquid may be either or both soluble and ~olid (the latter being held suspended by a moving stream). They may or may not be in a condition of lower valence o~ be subject to having toxicity destroyed by oxidization, but in any e~irent the flow is exposed to a strong oxidizing treatment (initially in a strongly acidic environment which is then shifted to a highly alkaline environment) in a moving ionic exchange medium which characteristic is furnished by a combination of ~fan der Waals surface action of particulate matter and by 7~5'77 galvanic charge imposed on such particles; one result of this is that gas bubbles (of air and suLfur dioxide) surface-adhere to and react with oxidiz-able particles and are repleni~hed by inert particles (carriers) transfer-ring similar bubbles to them. The flow is moved through successive treat-ing units at rates of flow determined by dimensionless numbers such as Reynolds, Schmidt Numbers, Peclet Numbers, Lehman Reaction ~umbers, Weber Numbers, Stanten Numbers and certain b~contact numbers. After alkaline treatment and continued gaseous oxidation, the non-liquid compo-nents are flocculated and separated as a sterile solid sludge. The latter 10 may then be digested and/or fractionated ~o concentrate and retrieve par-ticular ingredients of value, by use of known methods.
Whereas in the past it was only dimly appreciated that the SO2-iron oxidative reaction required the presence of~.free electrons (apparently trans-ferring between ions), it is now realized that it is highly desirable to pro-vide such a "gal~anic exchange " condition throughout the whole procedure and particularly in conjunction with (a3 turbulence or agitation, and (b) the intimate presence of gaseous oxygen continuing through successiv steps until the flocculating ion itself is oxidized. As already noted, the galvanic charge imposed on the particulate matter by the added electro-20 lytes (acid and basic reagents) promotes or accentuates the surface ad-hesion of gas to particle, and enables the interchange of electrons. Such a reacting state is then maintained, and phase separation prevented, by movement at a tailored flowl rate.
I~ypical surface-adsorbent particulate matter may be either oxidiz-able or non-oxidizable and includes cellulosic or other organic matter as well as inorganic compounds such as metallic oxides (alumina, magnesium oxide, calcium oxide, etc. ) and especially compounds of atoms which have a ~an der Waals packing radii of about 1. 9 or less. Additional examples of particulate matter include infusorial earth, diatomaceous earth, bentonite, 30 and siliceous matter such as free-flowing sand, silicones, etcO
_9_ ~L~7~LS77 In summary of the above, therefore, the present invelltion ma~ ce broad`y defined as that process for remov.iny ~rom a flowable polar-liquid as a solid substance, a dispersed soluble or .suspended con.taminant, of whi.ch any suspended par~icles thereof are characterized by Van der Waals effect and which contaminant is capable of solid existance at ambient operating temperature and pressure, the process compri.sing (a) di3pe.rsing in the liquid a minimum of about 0.1% w. random-mo~ing~particulate matter, which may either be added or be formed by fractionatlon of the contaminant when the latter is initially present in bulk, which dispersed particles thereof have a density of about l.OS to about 2.0 and a size of about 30 to about 225 microns diameter with free surface energy of about 100 to about 500 ergs/ cm2, and also reducing an~ additional solid matter present to such particle size, (b) providing a~ oxidation medium for such of the contarninant and added particles as may be capable of oxidation, by ma]cing such li~uid acidic, intirnately dispersing gaseous oxygen therein~ and providing a supply of free electrons as by acidic dissociation of the polar 2~ uid and by oxidation in situ of a heavy metal provided therein, which metal is characterized by the capacity of subsequentlv forming a flocculant precipitate in alkal.ine media, whereby a ~alvanic charge is imparted to the moving particles by random distribution and attachment of the electrons thereto, (c) maintainin~.
the cllarge on the moviny particles and restraining coagulation and phase separation of particles and soluble contam:inants during successive oxidative reaction periods by agitation effected at least in part by flowing the liquid and its contents through ele~trically-insulated and flow-connected reaction vessels in intimate rnixture with gaseous oxygen and at a variable flow rate defined by dimensionless parameters derlved from the internal size and shape of the respective vessels and their connectin~ conduits, ~ - 9a -,~,~1"
,s, "~,,", ,,~
697~577 (d) making the liquid alkaline~ subsequently ceasina aaitation and electrically grounding the alkaline liquid, whereby flocculating ions of the heavy metal provided therein, mutually precipate the charged particles, the metal ions and soluble contaminan~s, thus yie].ding an oxygen-containing supernatent pure liquid.
The process as indicated hereinabove may be ca.rried out broadly in an assembly for purification of contamirlated liquid, including liquid flow control means and comprising in combination the following sequentially connected units: (a) liquid container means including associated means for selectively ~macerating solid components of a thus-contaminated liquid, and gas delivery/aeration means for passing gas into intimate admixture with the contaminated liquid and macerated components,~b~
acidic treatment means, flow connected to the container means, and including means for regulation of pH by selective introduction of acidic and gaseous oxi.dizing reagents to the contaminated liquid, : ~c) container and reactant means, flow connected to the last treatment means, and comprising a source of soluble heavy metal ions adapted to mingle with the :Liquid flow stream, and -means for subsequently aerating the liquid flow by passing gaseous oxygen therethrough, (d) neutralization means, flow connected to th~
last aerating means, and including proximate means for introducing alkaline reagent into the liquid flow, and a plurality of successively distal means for intimately mi~ing gaseous o~ygen into the alkaline flow stream in amount adapted to restrain precipitation of contaminants by agitation thereof, (e) means for ~locculating separable contaminant components of the alkaline flow stream, substantially concurrent with electrical grounding of the stream, and switch means for electrically grounding the alkaline flow stream, each of the units starting with (b) being electrically insulated from ground support, and the floccu].ating means (e) being electrically insulated from the preceding flow ywl/ ~ - 9b -,,, .i ~ 7~7 connected unit, whereby a galvanic charge may be imparted t.o solid particles of the liquid flow by pH regulation and electrons of the soluble heavy metal lons and such charge maintained until discharged by the switch means.
Ywl/ - 9c -~7~ 577 BRIEF DESCRIPTION OF THE DR~WINGS:
Figures 1, 2, 3 show in semi-schematic representation, a process and apparatus embodying the present invention, with the various flow con-nections being horizontally alignable when the three sheets are placed side by side in~this order.
Figure 4 is a horizontal sectional view taken on line 4--4 through the soda ash treatment unit of Figure 1.
Figure 5 is a vertical sectional view on line 5--5 of the homogen-izer tank of Figure 2.
Figure 6 is an enlarged fragmentary detail of an end outlet segment 10 of an air delivery conduit of tanks 70 and 72.
TYPICAL FLOW PATTERN AND ~REATMENI UNITS:
In the illustrated apparatus, a flowable feed stock such as raw sew-age is introduced through an inlet conduit 10 into a wet well or ~f,ragment-ation chamber 12 where a chopper pump 14 reduces the solid matter to the required particle size (30 to 250 microns)O Liquid level in this chamber is regulated by an automatic control unit 16 which opens and closes a pinch valve 17 in the line~ From the wet well the particulate dispersion is moved to a primary or marshalling tank 18 through a conduit 19 as regulated by a liquid level control 20. In the absence of any or sufficient solid matter in the feedstock, the required particulate matter, which may be any inert 20 material which will hold a galvanic charge (e. g. shredded cellulose) is added to the wet well from a supply hopper ZZ by a conduit 23.
~ he comminuted feed stock is ultimately withdrawn from the primary tank 18 through conduit 24 at a rate determined by a suction pump Z5 and conveyed to a pulsation damper tank 27. A controlled quantity of exhaust gas is released from the top of the closedi:tank 18 through a wet charcoal ~1~7~577 filter unit 26 and vented (odorless) to the atmosphere. Within the pri-mary tank 18 is a submerged transfer pump 28 which is operated to maintain a continuous flow of fluid and suspended particles. ~urbtllence within tank 18 is contributed in part by the presence of internal baffles 29 and by continuous bubbles of a (recycled) gas mixture from conduit 30 which enter through perforations in the piping adjacent the flooring 31 of the tank. ~o the extent that the liquid medium is clear enough, it is vis-ually discernilble~ that small gas bubbles here adhere to the surface of the mo~ing solid particles within the liquid, and their gaseous oxygen con-10 tent (derived initially from air) plus SO2 pretreats or conditions oxidizableparticles for subsequent oxidation. In the case of highly oxidizable matter such as fecal debris, a residence~ time in the preliminary chamber 18 on the order of about one and a half to about two hours is indicatedO
From the pulsation dampener tank 27, the flow, at the rate controlled by mass flow meter 21, is moved through conduit 34 to a mixer tank 35 where it is intermingled with a gaseous mixture of sulfur dioxide and air, ~ ~7~~ '1/27~ ~;7) ~e rintroduced by drop lines 37 from an overhead gas mixing chamber 36. Re-cycled gas is introduced to the mixer chamber 36 through the line 38 com-ing fronl a co}npressor 40 which receives exhaust gas through line 4~;3, 20 passing through a silencer unit 43. Both the gas mixer 36 and the flow mixer tank 35 are at times supplied with liquid sulfur dioxide through line 45 from a supply tank 46 (which may be heated), in response to a pH meter 44 which maintains the tank 35 within the pH range of about 2. 0 to about 2. 5. Alternately or concurrently sulfur dioxide gas is supplied to the gas mixer 36 from supply source 47 through conduit 48, controlled by pH meter 44 and/or the mass flow meter 21. In tank 35, Peclet Numbers will range between g and 25. Lehman Reaction Numbers of the blow tubes 37 vary from 3.5 to 8; for eductors 25 to 30.
5~7 Exhaust gas from the tower 39 is continuously introduced into the iron rqaction chamber 50 as astream of bubbles through conduit 49, while at the same time the liquid flow containing a controlled amount of free gas bubbles is passed through an outfall conduit 52 and introduced through line 53 into the reaction chamber 50 below the porous bed. It is very important that gas inlet valve 49 be partially closed and thus used to mix its flow with the fluid flowing throug h the line 53. The gas mixture which is passed jointly through the scrap iron bed (which furnishes both ferrous and ferric ions to the medium) and through the liquid flow stream, should contain a 10 mixture of both nitrogen and oxygen (i. e., air). Vaporous mixture fro~n the stack 51 of the iron chamber is passed through the conduit 54 which separ-ates the non-gaseous components (i. e., liquid droplets) and returns them to the mixer tank 35 of the main flow by way of conduit S7 or into the dis-charge from tanks 70 or 72; the gaseous portion is recycled through the compre s s or gO by the line 570 Liquid outflow from the reaction tank 50 has a pH of about 3. 0 to about 30 5 and is passed through conduit bO to a blow tank 62 where air from a reservoir 63, by conduit 64 and manifold 65 is passed upward through the liquid so asto separate it and to again provide a fluid system ZO saturatecl with dissolved oxygenO The flow is generàlly red from ferrous ionsO Gaseous take-off from stack 61 by donduit 66, and gases from tanks 70 and 72 by lines 67, 68 are returned by line 30 to primary tank 180 From the blow tank, liquid outflow is conveyed to the lower level of the neutralizer tank by conduit 69. A conduit 74 connects a mixing throat 75 of the outflow conduit 69 to a caustic supply tank 76, and a conduit 78 con-nects a lime slurry source 79 and circulating pump 80 to the mixing throat 75, the alkali flow to the neutralizer 70 being controlled by a pH meter 77.
Instead of gradually neutralizing the acidic flow and progres sively bringing ~L~7~577 it to the required alkalinity of about pH 11, it has been found advantage-ous to introduce ~hrough the throat 75 at one time, substantially the whole quantity of alkali required to achieve the final pH for that immediate vol-ume of flow with which it is mixed.
The air reservoir 63 initiates a plurality of air delivery lines 83 to the neutralizer tank 70 and a similar series 88 to the homogenizer tank 72, which individual lines are disposed to emit a bubbling shearing air stream from indieidual sparger or wedge-aperture nozzles at their distal ends, thus agitating the churning or foaming mass of liquid and charged 10 particles at the same time that they supply oxygen and nitrogen. Conse-quently, the emerging outflow through conduits 71 and 73 is oxygen-satur -ated and the adsorbed gas on the particulate surface continues to be re-activeO ~he flow of air through the several lines 83, 88 is controlled by individual (manual) valves or orifice plates so that it can be adjusted to the"step by step" progression of the increasingly viscous flow and thus continually pre~rent agglomeration and sedimentation. A residence time of about 15 to 17 minutes in each $ank is t~pical; total about 30 to 40 minutes at about 60 - 80 F .
The air reservoir 63 is supplied by conduit 59 from an air com-20 pressor 89 connected to a silencer 91. The compressor processes freshair and in some instances may pass it~ough an ozonizer 98, such as the non-sparking, low voltage, AC, face-separated insulated-plate type describ-ed in U.S.Patent No.3,948,774. However, the basic procedure is sufficient-ly effective in most cases without the ad~itional oxidation provided by ozone.
~-o,7~/6 As seen particularly in Figure 2~` the several air lines 83, 88, each angularly dispose their terminal segment 100 transversely within the tank 70 or 72. It is formed with a closed end 101 and a blow outlet mouth 102 is cut wedge-shaped into the hemi-cylinder which is oriented downward . . .
~C~7~577 when disposed in the tank at a transverse angle to ~he longitudinal ver-tical plane of the chamber. Such positioning of the outlet minimizes the possibility of liquid back~low and consequent solid deposition or encrust-ation therein. Successive segments lO0 are mounted cri~sscross or at ~~ ` different~angles so that their outlet mouths are angularly staggered rela-tive to the longitudinal axis of the tank. Functionally, the flow-aligned tanks 70, 72 can be considered to provide the same continuing and accel-erating reaction process in tandem structural units -- that is, supporting completion of the neutralization process while keeping in suspension the lO forming flocculate in the increasingly viscous flowstream so as to restrain phase separation.
When it is desired to maximize removal of hardness components and silica, the outflow conduit 73 from the homogenizer tank 72 receives a soda ash increnlent from a supply tank 99 through line 84 and then passes through a heating zone or unit 85 where ~he flow is raised to a temperature of about 90 to about l 20F before introductLon to the treat-ment tank 82 where it is agitated by a motor driven agitator or marine type impeller 86. Location of four intermediate-length upstanding baffles 87 in the tank enables or directs the li~uid suspension to circulate in 20 closed paths of generally vertical ellipses between adjacent baffle s.
From the treatment tank 82, a conduit 90 carries the flow to a floc-culation chamber 92 which may have inclined walls and/or corrugated floor segments separated by upstanding baffles which form a convoluted pathway for descending sediment and liquid. Individual floor segments are movable by pneumatic actuators 93 driven by air lines 94. Each unit of the appar-atus has been electrically insulated from the ground and from successive (adjacent) units, being connected together by plastic conduits, the chambers preferably being formed of non-conductive material ~concrete, wood, etc. ) and in any event lined with corrosion-resistant layer such as plastic or 30 glass fiber.
~7~577 ~he flowstream or liquid medium may now be grounded by closing a switch 95 connected to an electrode 96 which is exposed to (i. e, inserted within) the fluid of the chamber 92. Consequent discharge of the galvanic charge carried by the particulate matter (which should now be oxidized to the extent possible), and cessation of agitation and flow, initiates a relatively rapid precipitation of the potentially solid components from the liquid medium. Residence time in the f~cculation chamber is on the order of about 30 to about 90 minutes. Distally the sludge, dark red-black from ferric ion, falls into a screw conveyor 97 which passes it through a screen classifier (not shown) and returns the liquid component to the system.
The liquid of the flocculation chamber 92 passes over an air-locked weir 104 into a decanted water tank 106 where a submerged pump 107 moves it through conduit 108 to woven strainer units 109, 110, which re-move colloids, and thence to an upper inlet of a packed tower 112 where it percolates down through raschig-like rings countercurrent to a stream of (possibly ozonized) air and is then introduced through the conduit ~3 to a holding tank 116. Air from the top of the tower is conveyed by line 114 to the decanted water tank 1060 Liquid outflow from the tower 112 passes through conduit 115 to a holding and aeration tank 116, which latter may be connected by a line 117 to a source of chlorine for optional use in particular circumstances (e. g.
when required by local ordinance)~ A compressor 120 with silencer 121 delivers fresh air through conduit 122 to the aeration tank 116 through lines 123, 124, and to a filtered water tank 125 through lines 126, 127, 128.
A gas take-off line 129 connects the filtered water tank 125 with a charcoal-filter exhaust unit 130. ~he latter is also connected by gas line 131 to the aeration tank 116. ~he tank 125 has a submerged pump 132 which move s liquid through conduit 133 to an ultimate polishing or holding tank 134. ~he aeration tank 116 is connected by pump 135 and liquid ~L0~577 conduit 136 to dual or alternate activated~charcoal filter tanks 137, 138, having drain lines 139, 140, which are joined to conduit 144 which termin-ates in the holding tank 125. A backwash line 142 collects fluid from filter tank 134 and delivers it to the decanted water tank 106. ~ return line 146 , ,~7~"~
connects the backflush outlets of the two filter tanks 137, 138 to the ~t~
~I water tank ~. Pump 132 in tank 125 provides product water or water for backwash through line 133 to filters 137, 138 and to product filter tank 134. A backwash line 146 connects the filter tank to the primary tank 18.
~he solids collected in the bottom of the flocculation tank 92 may contain toxins (which have not been detoxified by oxidation). Such can be metals such as mercury, arsenic, boron, lead, iron, gold, silvex, etc., as well as some biocides. Non-oxidative pyrolysis may be used to re-move organic materials such as petro-chemicals. Pre cipitates such as carbonates and su.lfates are decomposed and removed as carbon dioxide and sulfur dioxide. Nitrogen is removed as an inert gas. The metals may be volatised and recondensed or removed in a carbon matrix and then calcined/roasted in the presence of oxygen to prepare a composite of various metallic oxides~ The noble metals are recovered as a combined 20 metal concentrate. The particular procedure for any flowstream will be adapted of course to the specific components shown by analysis to be present and which it is desired to re~ov~r.
F LOW P~T TE RN:
container D velocity of density of Reynolds Number (NRe)=diameter( ) Xflowing fluidlv) x fluid media(P) Viscosity of flowing media (~
For example, the iron reaction chamber S0 has the characteristics --- ~7~57~
Diameter- Liquid Liquid Mass Air Mass NRMass Flow Ratio-feet velocity- Flow- lb/ft~hr Flow-lb/ft~/hr liquid/air ft/ se c.
lo 5 0~ 0143 1763 210 9678~ 395 2 ~ 0 0.0121 1984 Z30 14528~ 626 2~ 5 0.0124 2540 210 232012.095 2~ 75 0O 0116 2600 210 2613120381
1~D7~577 rrhUs hexavalant chromium is a toxic substance not releasable ~to the environrnent, Other toxic components of common cooling water additives are cyanides and phosphates, which must be detoxified before release.
Purification of polluted water for purposes of reuse, whether start-ing with agriculture /municipal sewage or with industrial waste, has been concerned primarily with recovery of potable water, only after the initial separation and disposal of solid components in an inert state, this being considered a necessary and preliminary step for any subsequent treatment.
~he solids may have then been utilized to a small extent as plant support 10 base or land fill, but such product is not a primary purpose for effecting the separation and for the most part the undifferentiated sludge is simply separated in bulk and discarded in the manner most convenient. Purifica-tion of the aqueous phase then takes place (if at all) as a successive, rather than concurrent, procedure. However, it will be rea-lized that the aqueous run-off from many and probably most water-treating procedures, (even if only involving flushing) carries a quantity of solid and potentially-solid ingredients having tangible economic value if such could only be re-covered in concentrated form without great expense.
Further, treatment of such masses of contaminated water in the past 20 has been primarily on a batch basis; large bodies of water being treated with acid or other reagent in a "settling basin" or even in successive chambers and chen allowed to stand for a prolonged period until spot checks show that the supernatent was clarified. In brief, it has not been realized that by careful regulation of the parameters of a flowing stream containing charged particles, separation/purification of an impure squeous medium could be effected in a fraction of the previous time, and also that the controls could be shifted so as to maximize the withdrawal of specific contaminants which it was desired to concentrate in the solid stateO Some ~L~7~57 ~
substances it may be desired to destroy -- as microorganisms, herbi-cides, pesticides and inorganic toxins -- or to recover, such as nitro-genous compounds, precious metals, etcL. Accordingly, the control para-meters of such flow treatment can now be accommodatad to a particular feed stock and with a view as to how it is wished to dispose of specific c ontaminants .
It has long beeD known to plarify waste wate r by oxidizing it in the joint presence of iron plus sulfur dioxide or an o~idizing a~ The im-purity is then removed by flocculating the iron in alkaline media. How-eve r, 'to the extent ~hat this process has been used, bulk solids necessar-ily were first removed as by filtration, and as to the remaining filtrate, past treatment does not remove dissolved impurities Isuch as inorganic salts typified by NaCl) or substances incapable of oxidation (such as metal particles): each of chese classes may include such undesirable toxins as arsenic, mercury, cadmium, lead, selenium, boron, etc.
SUMMARY OF TE~E INVENTION:
It has now been found that this dual oxidation/precipitation step can be incorporated into a composite treating process whereby essentially any flowable, polar liquid medium containing (:Einely fractionated) waste/refuse, as well as soluble salts and non-oxidizable impurities, can have all non-gaseous impurities removed as solids, leaving a sterile, pure, oxygen-containing liquid (e. g., potable water, which is also capable of supporting fish and other marine life). The precipitated material is also sterile and if desired can be further fractionated to recover substances of economic value, such as precious metals, fertilizer-enriched sludge, etcO
In brief, in a primary reaction vessel or multi-unit apparatus, all of which is electrically insulated, there is provided (in the absence of any ~7~5~
externally imposed electric current) a self-generated galvanic cell formed by "soluble" or free electrons resulting from acidic oxidation of a contain-ed heavy metal capable of alkaline flocculation, suc:h as iron and/or aluminum, as well as by free electrons produced by disassociation of water (or other polar media) by introduction of sulfur dioxide, A minimum suspension of minute particles (as hereafter definedj is also deliberately provided, ither by addition or by f ractionation of bulk solids initially presentO Such dispersed particles (preferably constituting all of the solid material present except for the electron-producing metal) inherently possess 10 random movement in the liquid medium (which movement is the Van der Waals effect resulting from an internally generated spin of an unsymmet-rical molecule). In conjunction with the moving electrons, this results in a distribution of charge to other particles and adhesion between charged microparticles and minute gas bubbles, which ultimately results in co~n-plete oxidation of all oxidizable material present. ~his necessary cross-distribution or random mixing of electrons with both charged and uncharged particles in the insulated cell may be accentuated by bubbling gaseous oxygen (air) and/or sulfur dioxide through the liquid, as well as by agi-tation of the body of liquid as by means of pump or stirrer. Electrical 20 insulation of each reaction vessel is necessary in order to keep such charge (maintained by pH regulation) from grounding through a conductive reaction vessel or flow conduit.
Under the step-wise oxidizing conditions and imposed galvanic flow pattern, metallic ions agglutinate with particulate matter and are replaced in the aqueous medium by other cations, i.eO ,hydrogen ions, at the same time maintaining the selected concentration of acidity. Among other reac-tions, part of such hydrogen ions couple with available nitrogen to form cJJ ~I ~Such ammonium ion then couples with ferrous ion to form (green) ferrous ammonium ion.
~ ~7~.S77 Successive cher~lical reaction steps can be effected by batch proce-dure, as long as sufficient agitation is provided to keep the ingredients from settling out prior to the ultimate and de sired flocculation. However, it is usually desirable to effect the process as a continuous flow, particu-larly when a continuing supply of feed stock is available, as from a muni-cipal sewage collection stream or similar industrial/agriculture waste flow.
Accordingly both the liquid medium and an associated gas stream are moved to and through successive treating zones or chambers. Ihe body of reactant gas (which should include oxygen) is channeled to contactingly e 10 overlie or flow through t~ lisLuid medium as the case may be.
Accordingly, by relating the size and shape of the reaction vessels and connecting conduits, a series of dimensionless parameters has been obtained for both the liquid and gas streams, by use of which controlled flow rates the material being treated is moved in a substantially contin-uous but step-wise pattern of reaction which prevents phase-separation while enabling or promoting electron clistribution until complete oxidation is effected. ~he final chemical-treatment step is then accomplished by ~JK~ 0~
all~i~ of the medium with avoidance of potential phase-separation during a preliminary digestion period followed by electrical grounding of 20 the medium concurrent with joint precipitation/flocculation of the metallic ions and the coagulated impurities. In addition, such grounding of the medium, which may be effectuated by grounding the insulated reaction vessel containing it, produces a noticeably more firmly-packed precipi-tate than would otherwise result.
When the composite impurity is composed of both (a) cellulosic material (eO g. ,food residues, waste paper or cartons, etc. ) and (b) sus-pended minerals or metals and/or soluble salts (e.g.,brackish water) the final alkaline flocculation tends to segregate "a" and "b" into successive layers with the "b" material being precipitated first or underneath the "al' ~- ~07~577 material. ~he procedure can thus be used to concentrate small quantities of precious metals from slurries and the like; in the event that "a"
material is not already mixed with it, the minimum charged particulate matter is added as described.
Separation of all potentially-solid components from such a flowing galvanic cell, by groundin~g and cessation of movement or agitation, in addition to re~noving in the flocculate such impurities as might previously be expected from the chemical reaction alone, now also draws soluble salts such as sodium chloride out of solution as well as precipitating sus-10 pended non-oxidizable particles. The only requirements for participating substances are that the liquid be a polar liquid, ancl the ~lid or potentially-solid substarlce be capable of the Van der Waals effectO In addition to water, other polar liquids are alcohols, acids, bases and other substances which ioniz;e or conduct an electric current. ~he dispersed particulate matter should constitute a minimum of about 0.1% w. and have a particle density of about 1. 05 to about 2. 0 and a1~e of about 30 to about 225 microns with free surface energy of about 100 to about 500 ergs/cmZ.
In this conne ction it will be realized that the smaller the particle size, the greater the relative surface area and the greater the forces of 20 surface attraction (relative to weight), so that the relative influence of gravity on the particle is correspondingly diminished. T hus the specific surface energy of a given solid can multiply more than 8000 times in going from approximately two inch di~eter to one micron. Its unit sur-face energy at the same time increases more than 600%. Accordingly, the greater the fractionation (maceration) of the bulk material into small par-ticles, the greater effect the increased surface energy will have on reaction and flow properties. Ihis factor is the same of course whether ~he material constitutes matter which (in addition to its carrier f~mction) is to be oxi-dized, or whether it is particulate matter added merely for its function of 30 carrying a charge in the flowing galvanic stream.
7~LSi77 However it will be apparent also that such fractionated particles, possessing Brownian movement and increased unit surface energy, have a strong tendency to coalesce if brought together; that is, they become a non-free-flowing mass rather than acting as independent discrete particles.
Such potential coagulation is prevented by (1~ pump action, mechanical agitation, and passage of gas currents through the liquid, each applied at a particular critical location, and (2) by moving the galvanic flow stream at a varied and deliberate rate in accordance with Reynolds Numbers and other dimensionless parameters selected to prevent phase separation. Thus 10 when later such suspended particles (galvanically charged) are finally di-rected to settle out, in cooperation with a flocculating ion, cancellation or grounding of the galvanic charge tremenduously reinforces this final (de-sired) phase separationO Thus one particularly notable and totally unexpec-ted result from this flowing galvanic cell and from the ~an der Waals sur-face effect exhibited by the particulate dispersion, is that by the present process soluble salts (in particular NaCl or other alkali halides) present in the liquid, also leave their state of solution and enter into the separat-ing flocculateO Such desalinification may be explained in part by continu-ation of the suspended flocculate in an oxygen-saturated medium until the 20 reduced flocculating ion (ferrous) is itself completely oxidized (to ferric ion).
To restate the present process: flowable contaminants of a liquid may be either or both soluble and ~olid (the latter being held suspended by a moving stream). They may or may not be in a condition of lower valence o~ be subject to having toxicity destroyed by oxidization, but in any e~irent the flow is exposed to a strong oxidizing treatment (initially in a strongly acidic environment which is then shifted to a highly alkaline environment) in a moving ionic exchange medium which characteristic is furnished by a combination of ~fan der Waals surface action of particulate matter and by 7~5'77 galvanic charge imposed on such particles; one result of this is that gas bubbles (of air and suLfur dioxide) surface-adhere to and react with oxidiz-able particles and are repleni~hed by inert particles (carriers) transfer-ring similar bubbles to them. The flow is moved through successive treat-ing units at rates of flow determined by dimensionless numbers such as Reynolds, Schmidt Numbers, Peclet Numbers, Lehman Reaction ~umbers, Weber Numbers, Stanten Numbers and certain b~contact numbers. After alkaline treatment and continued gaseous oxidation, the non-liquid compo-nents are flocculated and separated as a sterile solid sludge. The latter 10 may then be digested and/or fractionated ~o concentrate and retrieve par-ticular ingredients of value, by use of known methods.
Whereas in the past it was only dimly appreciated that the SO2-iron oxidative reaction required the presence of~.free electrons (apparently trans-ferring between ions), it is now realized that it is highly desirable to pro-vide such a "gal~anic exchange " condition throughout the whole procedure and particularly in conjunction with (a3 turbulence or agitation, and (b) the intimate presence of gaseous oxygen continuing through successiv steps until the flocculating ion itself is oxidized. As already noted, the galvanic charge imposed on the particulate matter by the added electro-20 lytes (acid and basic reagents) promotes or accentuates the surface ad-hesion of gas to particle, and enables the interchange of electrons. Such a reacting state is then maintained, and phase separation prevented, by movement at a tailored flowl rate.
I~ypical surface-adsorbent particulate matter may be either oxidiz-able or non-oxidizable and includes cellulosic or other organic matter as well as inorganic compounds such as metallic oxides (alumina, magnesium oxide, calcium oxide, etc. ) and especially compounds of atoms which have a ~an der Waals packing radii of about 1. 9 or less. Additional examples of particulate matter include infusorial earth, diatomaceous earth, bentonite, 30 and siliceous matter such as free-flowing sand, silicones, etcO
_9_ ~L~7~LS77 In summary of the above, therefore, the present invelltion ma~ ce broad`y defined as that process for remov.iny ~rom a flowable polar-liquid as a solid substance, a dispersed soluble or .suspended con.taminant, of whi.ch any suspended par~icles thereof are characterized by Van der Waals effect and which contaminant is capable of solid existance at ambient operating temperature and pressure, the process compri.sing (a) di3pe.rsing in the liquid a minimum of about 0.1% w. random-mo~ing~particulate matter, which may either be added or be formed by fractionatlon of the contaminant when the latter is initially present in bulk, which dispersed particles thereof have a density of about l.OS to about 2.0 and a size of about 30 to about 225 microns diameter with free surface energy of about 100 to about 500 ergs/ cm2, and also reducing an~ additional solid matter present to such particle size, (b) providing a~ oxidation medium for such of the contarninant and added particles as may be capable of oxidation, by ma]cing such li~uid acidic, intirnately dispersing gaseous oxygen therein~ and providing a supply of free electrons as by acidic dissociation of the polar 2~ uid and by oxidation in situ of a heavy metal provided therein, which metal is characterized by the capacity of subsequentlv forming a flocculant precipitate in alkal.ine media, whereby a ~alvanic charge is imparted to the moving particles by random distribution and attachment of the electrons thereto, (c) maintainin~.
the cllarge on the moviny particles and restraining coagulation and phase separation of particles and soluble contam:inants during successive oxidative reaction periods by agitation effected at least in part by flowing the liquid and its contents through ele~trically-insulated and flow-connected reaction vessels in intimate rnixture with gaseous oxygen and at a variable flow rate defined by dimensionless parameters derlved from the internal size and shape of the respective vessels and their connectin~ conduits, ~ - 9a -,~,~1"
,s, "~,,", ,,~
697~577 (d) making the liquid alkaline~ subsequently ceasina aaitation and electrically grounding the alkaline liquid, whereby flocculating ions of the heavy metal provided therein, mutually precipate the charged particles, the metal ions and soluble contaminan~s, thus yie].ding an oxygen-containing supernatent pure liquid.
The process as indicated hereinabove may be ca.rried out broadly in an assembly for purification of contamirlated liquid, including liquid flow control means and comprising in combination the following sequentially connected units: (a) liquid container means including associated means for selectively ~macerating solid components of a thus-contaminated liquid, and gas delivery/aeration means for passing gas into intimate admixture with the contaminated liquid and macerated components,~b~
acidic treatment means, flow connected to the container means, and including means for regulation of pH by selective introduction of acidic and gaseous oxi.dizing reagents to the contaminated liquid, : ~c) container and reactant means, flow connected to the last treatment means, and comprising a source of soluble heavy metal ions adapted to mingle with the :Liquid flow stream, and -means for subsequently aerating the liquid flow by passing gaseous oxygen therethrough, (d) neutralization means, flow connected to th~
last aerating means, and including proximate means for introducing alkaline reagent into the liquid flow, and a plurality of successively distal means for intimately mi~ing gaseous o~ygen into the alkaline flow stream in amount adapted to restrain precipitation of contaminants by agitation thereof, (e) means for ~locculating separable contaminant components of the alkaline flow stream, substantially concurrent with electrical grounding of the stream, and switch means for electrically grounding the alkaline flow stream, each of the units starting with (b) being electrically insulated from ground support, and the floccu].ating means (e) being electrically insulated from the preceding flow ywl/ ~ - 9b -,,, .i ~ 7~7 connected unit, whereby a galvanic charge may be imparted t.o solid particles of the liquid flow by pH regulation and electrons of the soluble heavy metal lons and such charge maintained until discharged by the switch means.
Ywl/ - 9c -~7~ 577 BRIEF DESCRIPTION OF THE DR~WINGS:
Figures 1, 2, 3 show in semi-schematic representation, a process and apparatus embodying the present invention, with the various flow con-nections being horizontally alignable when the three sheets are placed side by side in~this order.
Figure 4 is a horizontal sectional view taken on line 4--4 through the soda ash treatment unit of Figure 1.
Figure 5 is a vertical sectional view on line 5--5 of the homogen-izer tank of Figure 2.
Figure 6 is an enlarged fragmentary detail of an end outlet segment 10 of an air delivery conduit of tanks 70 and 72.
TYPICAL FLOW PATTERN AND ~REATMENI UNITS:
In the illustrated apparatus, a flowable feed stock such as raw sew-age is introduced through an inlet conduit 10 into a wet well or ~f,ragment-ation chamber 12 where a chopper pump 14 reduces the solid matter to the required particle size (30 to 250 microns)O Liquid level in this chamber is regulated by an automatic control unit 16 which opens and closes a pinch valve 17 in the line~ From the wet well the particulate dispersion is moved to a primary or marshalling tank 18 through a conduit 19 as regulated by a liquid level control 20. In the absence of any or sufficient solid matter in the feedstock, the required particulate matter, which may be any inert 20 material which will hold a galvanic charge (e. g. shredded cellulose) is added to the wet well from a supply hopper ZZ by a conduit 23.
~ he comminuted feed stock is ultimately withdrawn from the primary tank 18 through conduit 24 at a rate determined by a suction pump Z5 and conveyed to a pulsation damper tank 27. A controlled quantity of exhaust gas is released from the top of the closedi:tank 18 through a wet charcoal ~1~7~577 filter unit 26 and vented (odorless) to the atmosphere. Within the pri-mary tank 18 is a submerged transfer pump 28 which is operated to maintain a continuous flow of fluid and suspended particles. ~urbtllence within tank 18 is contributed in part by the presence of internal baffles 29 and by continuous bubbles of a (recycled) gas mixture from conduit 30 which enter through perforations in the piping adjacent the flooring 31 of the tank. ~o the extent that the liquid medium is clear enough, it is vis-ually discernilble~ that small gas bubbles here adhere to the surface of the mo~ing solid particles within the liquid, and their gaseous oxygen con-10 tent (derived initially from air) plus SO2 pretreats or conditions oxidizableparticles for subsequent oxidation. In the case of highly oxidizable matter such as fecal debris, a residence~ time in the preliminary chamber 18 on the order of about one and a half to about two hours is indicatedO
From the pulsation dampener tank 27, the flow, at the rate controlled by mass flow meter 21, is moved through conduit 34 to a mixer tank 35 where it is intermingled with a gaseous mixture of sulfur dioxide and air, ~ ~7~~ '1/27~ ~;7) ~e rintroduced by drop lines 37 from an overhead gas mixing chamber 36. Re-cycled gas is introduced to the mixer chamber 36 through the line 38 com-ing fronl a co}npressor 40 which receives exhaust gas through line 4~;3, 20 passing through a silencer unit 43. Both the gas mixer 36 and the flow mixer tank 35 are at times supplied with liquid sulfur dioxide through line 45 from a supply tank 46 (which may be heated), in response to a pH meter 44 which maintains the tank 35 within the pH range of about 2. 0 to about 2. 5. Alternately or concurrently sulfur dioxide gas is supplied to the gas mixer 36 from supply source 47 through conduit 48, controlled by pH meter 44 and/or the mass flow meter 21. In tank 35, Peclet Numbers will range between g and 25. Lehman Reaction Numbers of the blow tubes 37 vary from 3.5 to 8; for eductors 25 to 30.
5~7 Exhaust gas from the tower 39 is continuously introduced into the iron rqaction chamber 50 as astream of bubbles through conduit 49, while at the same time the liquid flow containing a controlled amount of free gas bubbles is passed through an outfall conduit 52 and introduced through line 53 into the reaction chamber 50 below the porous bed. It is very important that gas inlet valve 49 be partially closed and thus used to mix its flow with the fluid flowing throug h the line 53. The gas mixture which is passed jointly through the scrap iron bed (which furnishes both ferrous and ferric ions to the medium) and through the liquid flow stream, should contain a 10 mixture of both nitrogen and oxygen (i. e., air). Vaporous mixture fro~n the stack 51 of the iron chamber is passed through the conduit 54 which separ-ates the non-gaseous components (i. e., liquid droplets) and returns them to the mixer tank 35 of the main flow by way of conduit S7 or into the dis-charge from tanks 70 or 72; the gaseous portion is recycled through the compre s s or gO by the line 570 Liquid outflow from the reaction tank 50 has a pH of about 3. 0 to about 30 5 and is passed through conduit bO to a blow tank 62 where air from a reservoir 63, by conduit 64 and manifold 65 is passed upward through the liquid so asto separate it and to again provide a fluid system ZO saturatecl with dissolved oxygenO The flow is generàlly red from ferrous ionsO Gaseous take-off from stack 61 by donduit 66, and gases from tanks 70 and 72 by lines 67, 68 are returned by line 30 to primary tank 180 From the blow tank, liquid outflow is conveyed to the lower level of the neutralizer tank by conduit 69. A conduit 74 connects a mixing throat 75 of the outflow conduit 69 to a caustic supply tank 76, and a conduit 78 con-nects a lime slurry source 79 and circulating pump 80 to the mixing throat 75, the alkali flow to the neutralizer 70 being controlled by a pH meter 77.
Instead of gradually neutralizing the acidic flow and progres sively bringing ~L~7~577 it to the required alkalinity of about pH 11, it has been found advantage-ous to introduce ~hrough the throat 75 at one time, substantially the whole quantity of alkali required to achieve the final pH for that immediate vol-ume of flow with which it is mixed.
The air reservoir 63 initiates a plurality of air delivery lines 83 to the neutralizer tank 70 and a similar series 88 to the homogenizer tank 72, which individual lines are disposed to emit a bubbling shearing air stream from indieidual sparger or wedge-aperture nozzles at their distal ends, thus agitating the churning or foaming mass of liquid and charged 10 particles at the same time that they supply oxygen and nitrogen. Conse-quently, the emerging outflow through conduits 71 and 73 is oxygen-satur -ated and the adsorbed gas on the particulate surface continues to be re-activeO ~he flow of air through the several lines 83, 88 is controlled by individual (manual) valves or orifice plates so that it can be adjusted to the"step by step" progression of the increasingly viscous flow and thus continually pre~rent agglomeration and sedimentation. A residence time of about 15 to 17 minutes in each $ank is t~pical; total about 30 to 40 minutes at about 60 - 80 F .
The air reservoir 63 is supplied by conduit 59 from an air com-20 pressor 89 connected to a silencer 91. The compressor processes freshair and in some instances may pass it~ough an ozonizer 98, such as the non-sparking, low voltage, AC, face-separated insulated-plate type describ-ed in U.S.Patent No.3,948,774. However, the basic procedure is sufficient-ly effective in most cases without the ad~itional oxidation provided by ozone.
~-o,7~/6 As seen particularly in Figure 2~` the several air lines 83, 88, each angularly dispose their terminal segment 100 transversely within the tank 70 or 72. It is formed with a closed end 101 and a blow outlet mouth 102 is cut wedge-shaped into the hemi-cylinder which is oriented downward . . .
~C~7~577 when disposed in the tank at a transverse angle to ~he longitudinal ver-tical plane of the chamber. Such positioning of the outlet minimizes the possibility of liquid back~low and consequent solid deposition or encrust-ation therein. Successive segments lO0 are mounted cri~sscross or at ~~ ` different~angles so that their outlet mouths are angularly staggered rela-tive to the longitudinal axis of the tank. Functionally, the flow-aligned tanks 70, 72 can be considered to provide the same continuing and accel-erating reaction process in tandem structural units -- that is, supporting completion of the neutralization process while keeping in suspension the lO forming flocculate in the increasingly viscous flowstream so as to restrain phase separation.
When it is desired to maximize removal of hardness components and silica, the outflow conduit 73 from the homogenizer tank 72 receives a soda ash increnlent from a supply tank 99 through line 84 and then passes through a heating zone or unit 85 where ~he flow is raised to a temperature of about 90 to about l 20F before introductLon to the treat-ment tank 82 where it is agitated by a motor driven agitator or marine type impeller 86. Location of four intermediate-length upstanding baffles 87 in the tank enables or directs the li~uid suspension to circulate in 20 closed paths of generally vertical ellipses between adjacent baffle s.
From the treatment tank 82, a conduit 90 carries the flow to a floc-culation chamber 92 which may have inclined walls and/or corrugated floor segments separated by upstanding baffles which form a convoluted pathway for descending sediment and liquid. Individual floor segments are movable by pneumatic actuators 93 driven by air lines 94. Each unit of the appar-atus has been electrically insulated from the ground and from successive (adjacent) units, being connected together by plastic conduits, the chambers preferably being formed of non-conductive material ~concrete, wood, etc. ) and in any event lined with corrosion-resistant layer such as plastic or 30 glass fiber.
~7~577 ~he flowstream or liquid medium may now be grounded by closing a switch 95 connected to an electrode 96 which is exposed to (i. e, inserted within) the fluid of the chamber 92. Consequent discharge of the galvanic charge carried by the particulate matter (which should now be oxidized to the extent possible), and cessation of agitation and flow, initiates a relatively rapid precipitation of the potentially solid components from the liquid medium. Residence time in the f~cculation chamber is on the order of about 30 to about 90 minutes. Distally the sludge, dark red-black from ferric ion, falls into a screw conveyor 97 which passes it through a screen classifier (not shown) and returns the liquid component to the system.
The liquid of the flocculation chamber 92 passes over an air-locked weir 104 into a decanted water tank 106 where a submerged pump 107 moves it through conduit 108 to woven strainer units 109, 110, which re-move colloids, and thence to an upper inlet of a packed tower 112 where it percolates down through raschig-like rings countercurrent to a stream of (possibly ozonized) air and is then introduced through the conduit ~3 to a holding tank 116. Air from the top of the tower is conveyed by line 114 to the decanted water tank 1060 Liquid outflow from the tower 112 passes through conduit 115 to a holding and aeration tank 116, which latter may be connected by a line 117 to a source of chlorine for optional use in particular circumstances (e. g.
when required by local ordinance)~ A compressor 120 with silencer 121 delivers fresh air through conduit 122 to the aeration tank 116 through lines 123, 124, and to a filtered water tank 125 through lines 126, 127, 128.
A gas take-off line 129 connects the filtered water tank 125 with a charcoal-filter exhaust unit 130. ~he latter is also connected by gas line 131 to the aeration tank 116. ~he tank 125 has a submerged pump 132 which move s liquid through conduit 133 to an ultimate polishing or holding tank 134. ~he aeration tank 116 is connected by pump 135 and liquid ~L0~577 conduit 136 to dual or alternate activated~charcoal filter tanks 137, 138, having drain lines 139, 140, which are joined to conduit 144 which termin-ates in the holding tank 125. A backwash line 142 collects fluid from filter tank 134 and delivers it to the decanted water tank 106. ~ return line 146 , ,~7~"~
connects the backflush outlets of the two filter tanks 137, 138 to the ~t~
~I water tank ~. Pump 132 in tank 125 provides product water or water for backwash through line 133 to filters 137, 138 and to product filter tank 134. A backwash line 146 connects the filter tank to the primary tank 18.
~he solids collected in the bottom of the flocculation tank 92 may contain toxins (which have not been detoxified by oxidation). Such can be metals such as mercury, arsenic, boron, lead, iron, gold, silvex, etc., as well as some biocides. Non-oxidative pyrolysis may be used to re-move organic materials such as petro-chemicals. Pre cipitates such as carbonates and su.lfates are decomposed and removed as carbon dioxide and sulfur dioxide. Nitrogen is removed as an inert gas. The metals may be volatised and recondensed or removed in a carbon matrix and then calcined/roasted in the presence of oxygen to prepare a composite of various metallic oxides~ The noble metals are recovered as a combined 20 metal concentrate. The particular procedure for any flowstream will be adapted of course to the specific components shown by analysis to be present and which it is desired to re~ov~r.
F LOW P~T TE RN:
container D velocity of density of Reynolds Number (NRe)=diameter( ) Xflowing fluidlv) x fluid media(P) Viscosity of flowing media (~
For example, the iron reaction chamber S0 has the characteristics --- ~7~57~
Diameter- Liquid Liquid Mass Air Mass NRMass Flow Ratio-feet velocity- Flow- lb/ft~hr Flow-lb/ft~/hr liquid/air ft/ se c.
lo 5 0~ 0143 1763 210 9678~ 395 2 ~ 0 0.0121 1984 Z30 14528~ 626 2~ 5 0.0124 2540 210 232012.095 2~ 75 0O 0116 2600 210 2613120381
3 ~ 00 0.0118 2645 252 2900 10.496 A critical factor for such sewage or waste water treatment in the 10 presence of particulate matter and sulfite/sulfate ion or hydroxyl ion is defined as Shape Factor (SF) = ~1) DA wherein ~ = particulate HFA
concentration factor~
DA~ = norninal air lift Disengaging [Area HFA = waste fluid hydraulic flow area An operative SF range is from about 9~ 5 to about 11. 3; optimu~nlO~O. 5.
EXAMPLE:
l!~[unicipal sewage with the bulk solids reduced in size to the desig-nated particulate diameter was flowed through a processing assembly such as here illustrated, the initial acidity made pH 1. 5 to 2. 5 by introduction 20 of liquid and/or gaseous sulur dioxide. Ihe liquid flow was then moved through the serpentine flow pattern of tank 35 (shapè factor 9-10) at NR
of about 5000 to about 10, 000 when in contact with the gaseous flow and about 7000 to about 18,000 when not in contact with the gaseous flow; the gas mixture of S02 and air was moved at about NRe 400 to about 500~
After about 7-1/2 - 15 minutes residence in the iron reaction chamber 50, the flow was passed through the air-blow tank 62 and thence to the neutralizer tank 70 where the pH was increased from about 8. 5 to about 10. 0 during a period of about 15 minutes; it continued through the homo-genizing tank 72 for about 15 minutes while the pH increased to a maximum 30 of about 11.
~L~7~577 When the operation is particularly directed to removal of calcium and magnesium ions ("hardness" components) and also to reduce the con-centration of silica, 15-30% of the sludge removed from the screens (sub-sequent to flocculation) is returned to the homogenizer tank to augment the particulate concentration and increase interfacial surface area, thus--lype In Liquid System Particulate Particle size Density 3 Amount Interfacial Surface Dia.microns mg. /cm gO /liter area, cm2/liter Solution born 30-225 192-15000~ 3-0. 9 660-13000 Flocculants 100-350 300-35000 . 04-0. 3 25-4500 Precipitates 200-700 250- 5000~ 07-0. 09 14-135 Additive s &
soda ash 75-250 3Z0-1700 0O 10-16 40-4800 Recycle sludge 30-700 192-3500 0O 01-4.8 250-3360 Additives of such size include fly ash, carbon black, infusorial earth, etc.
The flow is then moved through an agitation and heating zone 82 at NRe of about 30, 000 to about 40,000 with addition of soda ash. Alternate ;~s to use of mechanical propellors, comp:Lete agitation with blown air may be , .
b.,`.'" 20 achieved when there is 1. 5-3. 0 CFM/~H~ft2 of cross section area.
Finally, the fluid flow is moved at NRe of about 2000 to about 3700 for about 30 to about 90 minutes through the flocculation tank or sediment-ation zone 92.
In retrospect, the addition of particulate matter b~ the present pro-cess may be distinguished from various incidental additio~s of particles to liquids in the past in that the latter were (a) for removal of dispersed colloids by adding charged particles in order to agglomerate the two sub-stances, or (b) f or removing a solute by addition of a substance which decreases the solubility of one or more of the dissolved components.
30 Neither of these treatments contemplates (or obtains) a continuing reaction ~7~5'77 ( oxidation) between the dispersed particles and a gaseous component adhered to the added particles, and/or the interplay of free electrons in such environment, which electrons take part in the desired continuing re-action. Nor do they contemplate deliberately maintaining such dispersion and preventing agglomeration during a necessary (multi-step) reaction period; nor final precipitation by introduction of a flocculating ion. In brief, the provision and utilization of an insulated flowing body of polar liquid constituting a galvanic or ionic exchange module (cell) the contents of which is continually manipulated both to prevent phase separation (pre-10 cipitation~ and to effect a desired chemical reaction (ultimately resultingin joint liquid purification and separation of solids) seems to have been entirely overlooked or unappreciated. Ihe necessary polar solvent such as water, contrasts with non-polar solvents such as mineral oil, paraffine, kerosene, etc., which are not suitable because of being incapable of trans-mitting an electric current.
It should be appreciated that the intended and necessary result from applying the dimensionless flow parameters related herein, is that (l)sedi-mentation and agglomeration are prevented, and (2) at their active surface area, the dispersed particles maintain the intermoleoular attraction, often 20 referred to as the Van der Waals effect, which attracts to and causes to adhere thereto clusters of moving air molecules (bubbles). ~he result is not only the progressive oxidation of the flowing particles, but also sub-sequently the electrical and interatomic field force which is thus continued, appears responsible for "drawing otlt~ of solution the dissolved electrolytes of both positive and negative charge, such as the halide (chlorine) ions and alkali (sodium) ions which finally are separated from the medium as one component of the flocculateO
In addition to the Reynolds Number which relates the fluid density and velocity with the container configuration, the following parameters - 1~17~L5~7 should be taken into account ~-The heat transfer and energy retaining properties of the flowing fluid are defined by the Peclet Number = DV~ Cp/k or Cp S~ R
k*4/ 3 D~
Cp = specific heat; ~ = surface tension k = thermal conductivityO The Peclet Number for tanks 70 and 72 is in the range of 12 to 32, and gas escape velocity at the surface is 0.18 to 0. 24 ft. /sec.
The Schmidt Number relates viscosity, density and container diameter (hydraulic diameter in an awkwardly shaped vessel) NSc =~ 1 DV.
The Stanton Number relates the coefficient of heat transfer (h) to the specific heat, velocity and density. NSt = h/C Vp.
The Stanton Number for the liquid flow gas mixing tank 35 is 35. 50 to 36. 20; for the neutralizer and homogenizer tanks 70, 72 the Stanton Number is 28.60 to 10,160.
The Weber Number relates the shape of the container (length of flew path L), the density, the velocity, and surface tension. NWe = Lfvj~ gc.
(:;ontact Number Nc = (UZ/~ g~ (NR ) (NS ) /
The iron tank 50 has an operable range Schmidt Number 4 x 10 to 1. 3 x 10 ; the contact number is 2Z8 to 446.
F~;action gases (air, sulfur dioxide, nitrogen, ozone, etc. ) can be introduced into the stream of particulate-laden fluid by eduction, sparge lines, or blow-shear tube. Each of these operates within a precise Lehman Reaction Number and ~Weber Number range. The dimensionless Lehman Re-action Number relates the System Shape ~actor and the mass flows of fluid and gase s .
System LRN Webe r Eductor system 25-30 1. 0-1. 7 Sparge Lines 3. 4-4. 4 0. 92-1. 98 Blow-Shear Tube 6. 7-7. 7 0. 98 1. 85 ~7~5~7 ~he terminal velocity of spherical and non-spherical droplets of particles settling in the vapor space will vary from 0O 4 to 30 ft. /sec, Particles up to 85 microns will be entrained and are removed prior to gas flow to the iron tank 50.
Flow conditions within the heater tank 85 are defined by a Reynolds Number of 3(), 000 to 40, 000 and a Grashof-Prandtl Number product within the range of 25, 600 to 230, 000 on the water-particulate matter side. Ihe Grashof Number = (L f gl~ b ~ r) where L equals length of reaction chamber; f - density; g = 3Z. 2 ft/ sec. ; ~ = viscosity;
10 b = coefficient of thermal expansion; T = temperatureO The Prendyl Number =~ where Cp is specific heat; ~ is viscosity; K is thermal conductivityO In removing hardness components, the heater tank is operated at a temperature of 105F ~5aF, the fluid leaving the tank between 100F and 110F. Introduction of additional particulate matter by line 103 into the line 73 (effluent from the homogenizer tank 72) as noted earlier, provides 3~to 85% more surface area in the final stages of magnesium conversion to magnesium carbonate and then to magnesium hydroxide (a solid). Magne~sium uxide and magnesium hSrdroxide also promote silica re-moval. The reintroduced sludge at this point, composed of mechanically zo formed particulate matter, flocculants and precipitates~ is very effective in assisting the soda ash in final removal of silica and magnesium. The electrical charge on the particulate matter also increases the rapidity and effectiveness of silica removal. Magnesium and calcium chlorides, sulfates and nitrates are converted to solid magnesium hydroxide and calcium car-bonate. Since ~a and Mg exist in hard water primarily as chloride, bi- -carbonate and sulfates, they are removed by che present process.
The way the present system handle hexavalent chromium and cyanides is of particular interest. As the recirculating gas stream of oxygen, nitro-gen and sulfur dioxide contacts the particulate matter and soluble salts, the ~7~5'77 sulfite ion reacts with any metallic ions present. Hexavalent chromiumis reduced to trivalent chromium in about 15 minutes at pH 2.0 to Z.5.
As a reductant, the sulfur dioxide consumes oxygen but the latter is con-tinually oeing replacedO In the iron reaction tank, ferrous sulfate is pro-duced, which also acts as a hexavalent chromium reductant. This insures complete conversion to trivalent chromiumO As the latter flows into the neutralization tank (with an initial pH of 8. 0 to 8. 5) its coupling with hydroxyl ion results in a light and voluminous precipitate which is continually mixed with the ferrous hydroxide thc~ is changing to ferric hydroxide (a heavier 10 precipitate). In a total residence time of about 30 minutes in tanks 70 and 7Z, this reaction goes to completion -- the precipitate continuing to be sus--pended as a result of air drive "churning" which maintains an oxygen-saturated medium-- the pH eventually reaching about 10. 5 to 10. 8 or 11.
Discharge conduit 73 delivers a finely dispersed, charged particle ~hat ag-glomerates rapidly in the region of the flocculation/sedimentation zone 92.
When cyanides are present it i9 necessary to oxidize them to cyanate a nd thence to free carbon d~oxide and nitrogen gas (both of which could be vented freely)~ IE cyanide ion were oxidized in acidic medium, cyanide gas would result and require special handling precautions. Alternately, if cyan-20 ide is oxidized to cyanate in highly basic medium, it requires an extendedreaction period. However, in the presence of the great amount of reactive oxygen carried by the particulate dispersion, cyanide can be oxidized to cy-anate at pH 8. 5 in approximately 5 minutes (in tank 70). If then this cyan-ate is exposed (i. e. returned by line 105) to oxygen and ferrous ion of the iron tank, an iron cyanate complex is formed. After passage through the blow tank 62, the flow reenters the neutralization tank 70 where hydroxyl ions react with the cyanate complex forming carbon dioxide and nitrogen.
At -the same ti~ne ferric sulfate is hydrolysed to ferric hydroxide; Fe(S04)3 + 6H2O = 2Fe(OH)3 + 3H2SO4O Upon grounding of the fluid, the ferric ~7~S~7 hydroxide separates as platelets which are as large as a quarter-inch across, dark red to black and firmly compacted in comparison with the fine, greyish, amorphous precipitate~ formed by ferrous hydroxide.
Waste water treatment by the pre sent system ~roduced the followin~--WA'rER PRIOR to 5'0 reduction of Initial con Sludge concentrate:
T:RE~1MEN~ centration found in Productspectrographic analysis Water prior to filtration pH 5.1 pH 7~ 2 pH 8. Z; sp. gr. l. 094 Al 430~ 0 mg/l 0. 5 mg/l 99~ 9% 33~ 700 % by wt.
Ca 616.0 536~ 0 13.0 1.080 Mg 145~ 8 53~ 5 63~ 33~ 230 Boron 105.0 16~ 6 84~ 2~ 190 Cu Iron 700~ 0 70~ 0 90~ 06~ 670 Silicon 1. 660 Titanium . 640 Mn 1.3 o20 84~61~030 Sodium 137500 1550.0 88~ 748~ 230 Potassium 240~ 14~ 5 94~ 02~ 810 99~ 249 %
Ammonia 5~ 85 96~ 6 T otal har dne s s (as CaCo3) 2140.01560.0 27~ 2 Fluoride 113.0 6~ 25 9~ 5 Chloride 1240~ 152.0 87~ 8 Sulfate 320004050~ 0 87~ 4 Phosphate . 2 ~ 2 T otal Organi c Carbon (TOC) 16. 018. 0 mg/l Free Carbon Dioxide (as CO2) 20~ 0 5~ 0 Total Di~solved Solids 62338~ 7598~ 87~ 8 Total Solids 69514 7652 89~ 0 Suspended Solids 717654~ 0 99~ 25 Chemical Oxygen Demand 765~ 0 38~ 3 95~ 00 ~olatile Solids 1599464~ 71 Di~ ss olved Oxygen 0 4~5 Surfactants 2~ 0 ~ 6 70~
Turbidity 18500 JTU35~ 0 JTU 99~ 8 units Spe cific conductance @ 25 C~ 45000 micromhos/
cm 7600 29.100 -23 ~
5~7 ~ he unexpected usefulness of the present (water)treating process in killing and a~glomerating viral and other monocellular life forms may be attributed to the cumulative effect or concurrence of a number of individual factors, at least some of which have a unique effect even alone. Ihese fac-tor s ar e - -(1) ~he broad band shit from extreme low to extreme high pH (i. e., 1. 5 to 11), as well as residence at each end of the spectrum, effects the range of organisms of which individual groups may be re sistant to acidic or basic media only, but not to extreme s of both pH.
10 (2) In this connection, the rapidity (e. g. 15 to 30 minutes)as well as the range or strength of the shift of pH appears important. An organism could better acclimate or survive slow or mild change.
(3) Residence time during which the whole medium or environment is under-going treatment at each end of the flow-process, comprising gaseous inter-change, continued suspension/agitation, oxidation and ion exchange, is sig-nificant~
concentration factor~
DA~ = norninal air lift Disengaging [Area HFA = waste fluid hydraulic flow area An operative SF range is from about 9~ 5 to about 11. 3; optimu~nlO~O. 5.
EXAMPLE:
l!~[unicipal sewage with the bulk solids reduced in size to the desig-nated particulate diameter was flowed through a processing assembly such as here illustrated, the initial acidity made pH 1. 5 to 2. 5 by introduction 20 of liquid and/or gaseous sulur dioxide. Ihe liquid flow was then moved through the serpentine flow pattern of tank 35 (shapè factor 9-10) at NR
of about 5000 to about 10, 000 when in contact with the gaseous flow and about 7000 to about 18,000 when not in contact with the gaseous flow; the gas mixture of S02 and air was moved at about NRe 400 to about 500~
After about 7-1/2 - 15 minutes residence in the iron reaction chamber 50, the flow was passed through the air-blow tank 62 and thence to the neutralizer tank 70 where the pH was increased from about 8. 5 to about 10. 0 during a period of about 15 minutes; it continued through the homo-genizing tank 72 for about 15 minutes while the pH increased to a maximum 30 of about 11.
~L~7~577 When the operation is particularly directed to removal of calcium and magnesium ions ("hardness" components) and also to reduce the con-centration of silica, 15-30% of the sludge removed from the screens (sub-sequent to flocculation) is returned to the homogenizer tank to augment the particulate concentration and increase interfacial surface area, thus--lype In Liquid System Particulate Particle size Density 3 Amount Interfacial Surface Dia.microns mg. /cm gO /liter area, cm2/liter Solution born 30-225 192-15000~ 3-0. 9 660-13000 Flocculants 100-350 300-35000 . 04-0. 3 25-4500 Precipitates 200-700 250- 5000~ 07-0. 09 14-135 Additive s &
soda ash 75-250 3Z0-1700 0O 10-16 40-4800 Recycle sludge 30-700 192-3500 0O 01-4.8 250-3360 Additives of such size include fly ash, carbon black, infusorial earth, etc.
The flow is then moved through an agitation and heating zone 82 at NRe of about 30, 000 to about 40,000 with addition of soda ash. Alternate ;~s to use of mechanical propellors, comp:Lete agitation with blown air may be , .
b.,`.'" 20 achieved when there is 1. 5-3. 0 CFM/~H~ft2 of cross section area.
Finally, the fluid flow is moved at NRe of about 2000 to about 3700 for about 30 to about 90 minutes through the flocculation tank or sediment-ation zone 92.
In retrospect, the addition of particulate matter b~ the present pro-cess may be distinguished from various incidental additio~s of particles to liquids in the past in that the latter were (a) for removal of dispersed colloids by adding charged particles in order to agglomerate the two sub-stances, or (b) f or removing a solute by addition of a substance which decreases the solubility of one or more of the dissolved components.
30 Neither of these treatments contemplates (or obtains) a continuing reaction ~7~5'77 ( oxidation) between the dispersed particles and a gaseous component adhered to the added particles, and/or the interplay of free electrons in such environment, which electrons take part in the desired continuing re-action. Nor do they contemplate deliberately maintaining such dispersion and preventing agglomeration during a necessary (multi-step) reaction period; nor final precipitation by introduction of a flocculating ion. In brief, the provision and utilization of an insulated flowing body of polar liquid constituting a galvanic or ionic exchange module (cell) the contents of which is continually manipulated both to prevent phase separation (pre-10 cipitation~ and to effect a desired chemical reaction (ultimately resultingin joint liquid purification and separation of solids) seems to have been entirely overlooked or unappreciated. Ihe necessary polar solvent such as water, contrasts with non-polar solvents such as mineral oil, paraffine, kerosene, etc., which are not suitable because of being incapable of trans-mitting an electric current.
It should be appreciated that the intended and necessary result from applying the dimensionless flow parameters related herein, is that (l)sedi-mentation and agglomeration are prevented, and (2) at their active surface area, the dispersed particles maintain the intermoleoular attraction, often 20 referred to as the Van der Waals effect, which attracts to and causes to adhere thereto clusters of moving air molecules (bubbles). ~he result is not only the progressive oxidation of the flowing particles, but also sub-sequently the electrical and interatomic field force which is thus continued, appears responsible for "drawing otlt~ of solution the dissolved electrolytes of both positive and negative charge, such as the halide (chlorine) ions and alkali (sodium) ions which finally are separated from the medium as one component of the flocculateO
In addition to the Reynolds Number which relates the fluid density and velocity with the container configuration, the following parameters - 1~17~L5~7 should be taken into account ~-The heat transfer and energy retaining properties of the flowing fluid are defined by the Peclet Number = DV~ Cp/k or Cp S~ R
k*4/ 3 D~
Cp = specific heat; ~ = surface tension k = thermal conductivityO The Peclet Number for tanks 70 and 72 is in the range of 12 to 32, and gas escape velocity at the surface is 0.18 to 0. 24 ft. /sec.
The Schmidt Number relates viscosity, density and container diameter (hydraulic diameter in an awkwardly shaped vessel) NSc =~ 1 DV.
The Stanton Number relates the coefficient of heat transfer (h) to the specific heat, velocity and density. NSt = h/C Vp.
The Stanton Number for the liquid flow gas mixing tank 35 is 35. 50 to 36. 20; for the neutralizer and homogenizer tanks 70, 72 the Stanton Number is 28.60 to 10,160.
The Weber Number relates the shape of the container (length of flew path L), the density, the velocity, and surface tension. NWe = Lfvj~ gc.
(:;ontact Number Nc = (UZ/~ g~ (NR ) (NS ) /
The iron tank 50 has an operable range Schmidt Number 4 x 10 to 1. 3 x 10 ; the contact number is 2Z8 to 446.
F~;action gases (air, sulfur dioxide, nitrogen, ozone, etc. ) can be introduced into the stream of particulate-laden fluid by eduction, sparge lines, or blow-shear tube. Each of these operates within a precise Lehman Reaction Number and ~Weber Number range. The dimensionless Lehman Re-action Number relates the System Shape ~actor and the mass flows of fluid and gase s .
System LRN Webe r Eductor system 25-30 1. 0-1. 7 Sparge Lines 3. 4-4. 4 0. 92-1. 98 Blow-Shear Tube 6. 7-7. 7 0. 98 1. 85 ~7~5~7 ~he terminal velocity of spherical and non-spherical droplets of particles settling in the vapor space will vary from 0O 4 to 30 ft. /sec, Particles up to 85 microns will be entrained and are removed prior to gas flow to the iron tank 50.
Flow conditions within the heater tank 85 are defined by a Reynolds Number of 3(), 000 to 40, 000 and a Grashof-Prandtl Number product within the range of 25, 600 to 230, 000 on the water-particulate matter side. Ihe Grashof Number = (L f gl~ b ~ r) where L equals length of reaction chamber; f - density; g = 3Z. 2 ft/ sec. ; ~ = viscosity;
10 b = coefficient of thermal expansion; T = temperatureO The Prendyl Number =~ where Cp is specific heat; ~ is viscosity; K is thermal conductivityO In removing hardness components, the heater tank is operated at a temperature of 105F ~5aF, the fluid leaving the tank between 100F and 110F. Introduction of additional particulate matter by line 103 into the line 73 (effluent from the homogenizer tank 72) as noted earlier, provides 3~to 85% more surface area in the final stages of magnesium conversion to magnesium carbonate and then to magnesium hydroxide (a solid). Magne~sium uxide and magnesium hSrdroxide also promote silica re-moval. The reintroduced sludge at this point, composed of mechanically zo formed particulate matter, flocculants and precipitates~ is very effective in assisting the soda ash in final removal of silica and magnesium. The electrical charge on the particulate matter also increases the rapidity and effectiveness of silica removal. Magnesium and calcium chlorides, sulfates and nitrates are converted to solid magnesium hydroxide and calcium car-bonate. Since ~a and Mg exist in hard water primarily as chloride, bi- -carbonate and sulfates, they are removed by che present process.
The way the present system handle hexavalent chromium and cyanides is of particular interest. As the recirculating gas stream of oxygen, nitro-gen and sulfur dioxide contacts the particulate matter and soluble salts, the ~7~5'77 sulfite ion reacts with any metallic ions present. Hexavalent chromiumis reduced to trivalent chromium in about 15 minutes at pH 2.0 to Z.5.
As a reductant, the sulfur dioxide consumes oxygen but the latter is con-tinually oeing replacedO In the iron reaction tank, ferrous sulfate is pro-duced, which also acts as a hexavalent chromium reductant. This insures complete conversion to trivalent chromiumO As the latter flows into the neutralization tank (with an initial pH of 8. 0 to 8. 5) its coupling with hydroxyl ion results in a light and voluminous precipitate which is continually mixed with the ferrous hydroxide thc~ is changing to ferric hydroxide (a heavier 10 precipitate). In a total residence time of about 30 minutes in tanks 70 and 7Z, this reaction goes to completion -- the precipitate continuing to be sus--pended as a result of air drive "churning" which maintains an oxygen-saturated medium-- the pH eventually reaching about 10. 5 to 10. 8 or 11.
Discharge conduit 73 delivers a finely dispersed, charged particle ~hat ag-glomerates rapidly in the region of the flocculation/sedimentation zone 92.
When cyanides are present it i9 necessary to oxidize them to cyanate a nd thence to free carbon d~oxide and nitrogen gas (both of which could be vented freely)~ IE cyanide ion were oxidized in acidic medium, cyanide gas would result and require special handling precautions. Alternately, if cyan-20 ide is oxidized to cyanate in highly basic medium, it requires an extendedreaction period. However, in the presence of the great amount of reactive oxygen carried by the particulate dispersion, cyanide can be oxidized to cy-anate at pH 8. 5 in approximately 5 minutes (in tank 70). If then this cyan-ate is exposed (i. e. returned by line 105) to oxygen and ferrous ion of the iron tank, an iron cyanate complex is formed. After passage through the blow tank 62, the flow reenters the neutralization tank 70 where hydroxyl ions react with the cyanate complex forming carbon dioxide and nitrogen.
At -the same ti~ne ferric sulfate is hydrolysed to ferric hydroxide; Fe(S04)3 + 6H2O = 2Fe(OH)3 + 3H2SO4O Upon grounding of the fluid, the ferric ~7~S~7 hydroxide separates as platelets which are as large as a quarter-inch across, dark red to black and firmly compacted in comparison with the fine, greyish, amorphous precipitate~ formed by ferrous hydroxide.
Waste water treatment by the pre sent system ~roduced the followin~--WA'rER PRIOR to 5'0 reduction of Initial con Sludge concentrate:
T:RE~1MEN~ centration found in Productspectrographic analysis Water prior to filtration pH 5.1 pH 7~ 2 pH 8. Z; sp. gr. l. 094 Al 430~ 0 mg/l 0. 5 mg/l 99~ 9% 33~ 700 % by wt.
Ca 616.0 536~ 0 13.0 1.080 Mg 145~ 8 53~ 5 63~ 33~ 230 Boron 105.0 16~ 6 84~ 2~ 190 Cu Iron 700~ 0 70~ 0 90~ 06~ 670 Silicon 1. 660 Titanium . 640 Mn 1.3 o20 84~61~030 Sodium 137500 1550.0 88~ 748~ 230 Potassium 240~ 14~ 5 94~ 02~ 810 99~ 249 %
Ammonia 5~ 85 96~ 6 T otal har dne s s (as CaCo3) 2140.01560.0 27~ 2 Fluoride 113.0 6~ 25 9~ 5 Chloride 1240~ 152.0 87~ 8 Sulfate 320004050~ 0 87~ 4 Phosphate . 2 ~ 2 T otal Organi c Carbon (TOC) 16. 018. 0 mg/l Free Carbon Dioxide (as CO2) 20~ 0 5~ 0 Total Di~solved Solids 62338~ 7598~ 87~ 8 Total Solids 69514 7652 89~ 0 Suspended Solids 717654~ 0 99~ 25 Chemical Oxygen Demand 765~ 0 38~ 3 95~ 00 ~olatile Solids 1599464~ 71 Di~ ss olved Oxygen 0 4~5 Surfactants 2~ 0 ~ 6 70~
Turbidity 18500 JTU35~ 0 JTU 99~ 8 units Spe cific conductance @ 25 C~ 45000 micromhos/
cm 7600 29.100 -23 ~
5~7 ~ he unexpected usefulness of the present (water)treating process in killing and a~glomerating viral and other monocellular life forms may be attributed to the cumulative effect or concurrence of a number of individual factors, at least some of which have a unique effect even alone. Ihese fac-tor s ar e - -(1) ~he broad band shit from extreme low to extreme high pH (i. e., 1. 5 to 11), as well as residence at each end of the spectrum, effects the range of organisms of which individual groups may be re sistant to acidic or basic media only, but not to extreme s of both pH.
10 (2) In this connection, the rapidity (e. g. 15 to 30 minutes)as well as the range or strength of the shift of pH appears important. An organism could better acclimate or survive slow or mild change.
(3) Residence time during which the whole medium or environment is under-going treatment at each end of the flow-process, comprising gaseous inter-change, continued suspension/agitation, oxidation and ion exchange, is sig-nificant~
(4) Relative density and composition of particulate matter in the flow-medium, compared to tl~ volume of water being treated is an important parameter.
(~otal area particles cm2/lO ~ 130 to 13, 280. ) 20 (5) ~he additional effect (attraction to living or newly deadcells) contributed by the galvanic charge which is carried by the particles is effective. In this connection, it is preferred to obtain the initial low adicity (plus galvanic charge) by introduction of sulfur dioxide, rather than by addition of formed acid, since the SO2 produce~ hydrogen ions and shifting electrons by dis-as s ociation of water .
(6) Detergent action results from sulfonation of fat and oil components of the medium and especially from such ingredients which may form part of the viral/bacterium capsule/membrane. Protenaceous components of the rnembrane may also co~ugate; subsec!uent salting out of the organic salts ~3~73~5~77 then exposes the cell contents to caustic attack or saponification.(7) Under these critical conditions, lime is particularly effective against some viruses.
(8) Rapidity and completeness of flocculation is impoIltant, e. g. 5 to 7 minutes after grounding, in comparison with a minimum of 25 to 35 min-utes or more which might be required in "merely" clarifying murky water by flocculating with Al or Fe ions.
(9) The total kill is achieved without recourse to chlorine or other toxic agent, and wi$hout need to modify the treatment so as to target it at a 10 specific organism first determined to be present. Such process can be used to "harvest" pestilential life forms for identification and study; by extracting samples from successive process steps, the susceptibility of the cell to each step is learned.
(~otal area particles cm2/lO ~ 130 to 13, 280. ) 20 (5) ~he additional effect (attraction to living or newly deadcells) contributed by the galvanic charge which is carried by the particles is effective. In this connection, it is preferred to obtain the initial low adicity (plus galvanic charge) by introduction of sulfur dioxide, rather than by addition of formed acid, since the SO2 produce~ hydrogen ions and shifting electrons by dis-as s ociation of water .
(6) Detergent action results from sulfonation of fat and oil components of the medium and especially from such ingredients which may form part of the viral/bacterium capsule/membrane. Protenaceous components of the rnembrane may also co~ugate; subsec!uent salting out of the organic salts ~3~73~5~77 then exposes the cell contents to caustic attack or saponification.(7) Under these critical conditions, lime is particularly effective against some viruses.
(8) Rapidity and completeness of flocculation is impoIltant, e. g. 5 to 7 minutes after grounding, in comparison with a minimum of 25 to 35 min-utes or more which might be required in "merely" clarifying murky water by flocculating with Al or Fe ions.
(9) The total kill is achieved without recourse to chlorine or other toxic agent, and wi$hout need to modify the treatment so as to target it at a 10 specific organism first determined to be present. Such process can be used to "harvest" pestilential life forms for identification and study; by extracting samples from successive process steps, the susceptibility of the cell to each step is learned.
Claims (21)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. That process for removing from a flowable polar-liquid as a solid substance, a dispersed soluble or suspended contaminant, of which any suspended particles thereof are characterized by Van der Waals effect and which contaminant is capable of solid existance at ambient operating temperature and pressure, said process comprising:
(a) dispersing in said liquid a minimum of about 0.1% w. random-moving particulate matter, which may either be added or be formed by fractionation of said contaminant when the latter is initially present in bulk, which dispersed particles thereof have a density of about 1.05 to about 2.0 and a size of about 30 to about 225 microns diameter with free surface energy of about 100 to about 500 ergs/ cm2, and also reducing any additional solid matter present to such particle size, (b) providing an oxidation medium for such of the contaminant and added particles as may be capable of oxidation, by making such liquid acidic, intimately dispersing gaseous oxygen therein, and providing a supply of free electrons as by acidic dissociation of the polar liquid and by oxidation in situ of a heavy metal provided therein, which metal is characterized by the capacity of subsequently forming a flocculant precipitate in alkaline media, whereby a galvanic charge is imparted to the moving particles by random distribution and attachment of the electrons thereto, (c) maintaining said charge on the moving particles and restraining coagulation and phase separation of particles and soluble contaminants during successive oxidative reaction periods by agitation effected at least in part by flowing the liquid and its contents through electrically-insulated and flow-connected reaction vessels in intimate mixture with gaseous oxygen and at a variable flow rate defined by dimensionless parameters derived from the internal size and shape of the respective vessels and their connecting conduits, (d) making said liquid alkaline, subsequently ceasing agitation and electrically grounding the alkaline liquid, whereby flocculating ions of the heavy metal provided therein, mutually precipitate the charged particles, the metal ions and soluble contaminants, thus yielding an oxygen-containing supernatent pure liquid.
(a) dispersing in said liquid a minimum of about 0.1% w. random-moving particulate matter, which may either be added or be formed by fractionation of said contaminant when the latter is initially present in bulk, which dispersed particles thereof have a density of about 1.05 to about 2.0 and a size of about 30 to about 225 microns diameter with free surface energy of about 100 to about 500 ergs/ cm2, and also reducing any additional solid matter present to such particle size, (b) providing an oxidation medium for such of the contaminant and added particles as may be capable of oxidation, by making such liquid acidic, intimately dispersing gaseous oxygen therein, and providing a supply of free electrons as by acidic dissociation of the polar liquid and by oxidation in situ of a heavy metal provided therein, which metal is characterized by the capacity of subsequently forming a flocculant precipitate in alkaline media, whereby a galvanic charge is imparted to the moving particles by random distribution and attachment of the electrons thereto, (c) maintaining said charge on the moving particles and restraining coagulation and phase separation of particles and soluble contaminants during successive oxidative reaction periods by agitation effected at least in part by flowing the liquid and its contents through electrically-insulated and flow-connected reaction vessels in intimate mixture with gaseous oxygen and at a variable flow rate defined by dimensionless parameters derived from the internal size and shape of the respective vessels and their connecting conduits, (d) making said liquid alkaline, subsequently ceasing agitation and electrically grounding the alkaline liquid, whereby flocculating ions of the heavy metal provided therein, mutually precipitate the charged particles, the metal ions and soluble contaminants, thus yielding an oxygen-containing supernatent pure liquid.
2. A process according to claim 1 wherein said oxidation medium of (b) comprises sulfite and sulfurous ions and is made pH of about 2 to about 2.5, and said heavy metal comprises iron.
3. A process according to claim 1 or 2 wherein the liquid of (d) is made pH of about 10 to about 11.
4. A process according to claim 1, or 2 wherein said polar liquid is predominantly water.
5. A process according to claim 1 wherein said flowable polar liquid comprises sewage/refuse containing bulk solids which are substantially reduced to the particle size of (a).
6. A process according to claim 1 or 5 wherein an inorganic salt is a soluble contaminant of the polar liquid and is substantially removed therefrom in the precipitate of (d).
7. A process according to claim 1, 2 or 5 wherein said dimensionless parameters are selected from a group comprising Reynolds Numbers, Peclet Numbers, Lehman Reaction Numbers, Shoup Factors, Schmidt Numbers, Contact Numbers, Weber Numbers, Grashaf-prandtl Numbers, and Stanton Numbers.
8. A process according to claim 1 wherein the suspended contaminant comprises fecal matter which is reduced to the particle size of (a) in situ.
9. A process according to claim 1 wherein sodium chloride is a soluble contaminant of the polar liquid which is water.
10. A process according to claim 1 wherein the soluble contaminant comprises hexavalent chromium or cyanide ion.
11. A process according to claim 2 wherein said contaminant comprises hexavalent chromium and said process includes the steps of reducing hexavalent chromium to trivalent chromium by reaction with sulfite and ferrous ions in the presence of ferrous sulfate at pH about 2.0 to about 2.5, then converting trivalent chromium to chromium hydroxide at pH
about 10.5 to about 11.0, and jointly precipitating same in admixture with ferric hydroxide.
about 10.5 to about 11.0, and jointly precipitating same in admixture with ferric hydroxide.
12. A process according to claim 10 wherein said contaminant comprises soluble cyanide and said process includes the steps of oxidizing the cyanide to cyanate at about pH 8.5 in said particulate carrying liquid, which liquid is substan-tially saturated with gaseous oxygen, then forming an iron cyanate complex by reaction of the cyanate with ferrous ion, then making the liquid alkaline and converting the complex to carbon dioxide and nitrogen by reaction with hydroxyl ion.
13. A process according to claim 1 wherein prior to the flocculation of the charged particles and contaminants, there is reintroduced to said liquid about 15% to about 30% of flocculated sludge plus soda ash, and the resultant mixture is heated at about 100°F to about 110°F with agitation, and then flocculated as recited in (d), thereby increasing the removal of silica, magnesium and calcium from the liquid.
14. A process according to claim 1 or 13 wherein the heated liquid flow is moved through a zone adapted addition-ally to receive and intermingle therewith soda ash and recycled sludge, said flow being moved in accordance with the dimension-less parameters: Reynolds Number 30,000 to 40,000 and Grashof-Prandtl Number product 25,600 to 230,000.
15. A process according to claims l or 2 wherein said oxidation medium of "b" is moved through a zone wherein said heavy metal produces free electrons, at a Reynolds Number of about 967 to 2900, a Shape Factor of 9.5 to 11.3, a Schmidt Number of 4 x 10-7 to 1.3 x 10-6, and a Contact Number of 228 to 446.
16. A process according to claims 1 or 2 wherein said polar liquid is moved through a zone wherein gas is mixed therewith in accordance with the dimensionless parameters:
Peclet Number 9 to 25, Shape Factor 9 to 10, a Reynolds number of 400 to 500 for gas flow, 5000 to 10,000 with gas contact and 7000 to 18,000 without gas contact, a Lehman Reaction Number of 3.5 to 8 for blow tubes carrying gas into said zone, and a Stanton Number of 35.500 to 36.20.
Peclet Number 9 to 25, Shape Factor 9 to 10, a Reynolds number of 400 to 500 for gas flow, 5000 to 10,000 with gas contact and 7000 to 18,000 without gas contact, a Lehman Reaction Number of 3.5 to 8 for blow tubes carrying gas into said zone, and a Stanton Number of 35.500 to 36.20.
17. A process according to claim 1, 2 or 5 wherein the alkalation of "d" is effected in a zone of liquid flow which is agitated by air moved countercurrant therethrough, said liquid being moved at a Peclet Number of 12 to 32 and the air being introduced therein by sparge lines having a Lehman Reaction Number of 3.4 to 4.4 or by blow shear tubes having a Lehman Reaction Number of 6.7 to 7.7, and a Stanton Number of 28.60 to 10,160.
18. A process according to claim 1, 2 or 5 wherein the flocculation and precipitation of "d" is effected in a zone wherein the flow is moved at a Reynolds Number of 2000 to 3700.
19. An assembly for purification of contaminated liquid, including liquid flow control means and comprising in combination the following sequentially connected units:
(a) liquid container means including associated means for selectively macerating solid components of a thus-contaminated liquid, and gas delivery/aeration means for passing gas into intimate admixture with said contaminated liquid and macerated components, (b) acidic treatment means, flow connected to said container means, and including means for regulation of pH by selective introduction of acidic and gaseous oxidizing reagents to the contaminated liquid, (c) container and reactant means, flow connected to said last treatment means, and comprising a source of soluble heavy metal ions adapted to mingle with the liquid flow stream, and means for subsequently aerating the liquid flow by passing gaseous oxygen therethrough, (d) neutralization means, flow connected to said last aerating means, and including proximate means for introducing alkaline reagent into the liquid flow, and a plurality of successively distal means for intimately mixing gaseous oxygen into the alkaline flow stream in amount adapted to restrain precipitation of contaminants by agitation thereof, (e) means for flocculating separable contaminant components of the alkaline flow stream, substantially concurrent with electrical grounding of said stream, and switch means for electrically grounding said alkaline flow stream, each of said units starting with (b) being electric-ally insulated from ground support, and said flocculating means (e) being electrically insulated from the preceding flow connected unit, whereby a galvanic charge may be imparted to solid particles of the liquid flow by pH regulation and electrons of said soluble heavy metal ions and such charge maintained until discharged by the switch means.
(a) liquid container means including associated means for selectively macerating solid components of a thus-contaminated liquid, and gas delivery/aeration means for passing gas into intimate admixture with said contaminated liquid and macerated components, (b) acidic treatment means, flow connected to said container means, and including means for regulation of pH by selective introduction of acidic and gaseous oxidizing reagents to the contaminated liquid, (c) container and reactant means, flow connected to said last treatment means, and comprising a source of soluble heavy metal ions adapted to mingle with the liquid flow stream, and means for subsequently aerating the liquid flow by passing gaseous oxygen therethrough, (d) neutralization means, flow connected to said last aerating means, and including proximate means for introducing alkaline reagent into the liquid flow, and a plurality of successively distal means for intimately mixing gaseous oxygen into the alkaline flow stream in amount adapted to restrain precipitation of contaminants by agitation thereof, (e) means for flocculating separable contaminant components of the alkaline flow stream, substantially concurrent with electrical grounding of said stream, and switch means for electrically grounding said alkaline flow stream, each of said units starting with (b) being electric-ally insulated from ground support, and said flocculating means (e) being electrically insulated from the preceding flow connected unit, whereby a galvanic charge may be imparted to solid particles of the liquid flow by pH regulation and electrons of said soluble heavy metal ions and such charge maintained until discharged by the switch means.
20. An assembly according to claim 19 which includes between units (d) and (e), means for simultaneously heating and agitating the alkaline flow stream while continually restraining precipitation.
21. An assembly according to claim 19 wherein unit (d) comprises an elongated chamber and said oxygen mixing means which is located distal to the alkaline introducing means, comprises successive downstream gas delivery conduits individually having ejection nozzles transversely disposed within the flow stream at successive staggered angular displacement from the longitudinal axis of the chamber, which conduits have individual flow control means whereby the gas inflow therethrough may be adjusted to changing turbidity of the flow stream immediately adjacent each nozzle.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA257,306A CA1071577A (en) | 1976-07-20 | 1976-07-20 | Galvanic flow system for joint particulate recovery and liquid purification |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA257,306A CA1071577A (en) | 1976-07-20 | 1976-07-20 | Galvanic flow system for joint particulate recovery and liquid purification |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1071577A true CA1071577A (en) | 1980-02-12 |
Family
ID=4106455
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA257,306A Expired CA1071577A (en) | 1976-07-20 | 1976-07-20 | Galvanic flow system for joint particulate recovery and liquid purification |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1071577A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114790018A (en) * | 2022-03-08 | 2022-07-26 | 中材国际环境工程（北京）有限公司 | Electric flocculation device and method for treating wastewater by adopting same |
-
1976
- 1976-07-20 CA CA257,306A patent/CA1071577A/en not_active Expired
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114790018A (en) * | 2022-03-08 | 2022-07-26 | 中材国际环境工程（北京）有限公司 | Electric flocculation device and method for treating wastewater by adopting same |
| CN114790018B (en) * | 2022-03-08 | 2023-12-12 | 中材国际环境工程（北京）有限公司 | Electric flocculation device and method for treating wastewater by adopting same |
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