DE1792391A1 - Purification of drinking water and waste water - Google Patents

Description

Purification of drinking water and sewage

The present invention relates to a method of cleaning of drinking water, private sanitary sewage, aqueous industrial waste and aqueous process streams, the is characterized by the following stages, addition dea Water to a primary water-soluble inorganic coagulant, at least one organic polyelectrolyte isoh en coagulating agents and acid-treated aerosols, Stir the mixture until a fluffy precipitate has formed, allow the fluffy precipitate to settle and Obtaining the purified water. The aforementioned method gives excellent removal of organics and phosphates from the treated water in the primary Treatment stage

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That. most drinking water and aicht potable water that too used for industrial purposes, will «« up removal of Substances that cloud the water and cause undesirable effects Give color, clarified. It is bound up with these substances mainly about non-settling colloidal »silt and clay, Phosphates from detergents and small structures from organic substances Substance, living plants and microorganisms that normally found in surface waters such as lakes, rivers, streams, etc. will. The colloidal silt particles give up the greatest problems, since they are present at all times and at certain times Camping due to heavy rainfall, melting snow, strong Winds etc. are present in high concentrations.

Under certain conditions where the concentrations of these undesirable substances do not exceed a low level, can be a pretty effective removal merely being effected by slow sand filtration »· Coagulation, however, is essential if the primary objective of treatment is removal of opacity, phosphates, organic paint and bacteria is. In some water treatment plants where additional Treatment such as pre-chlorination, removal of flavor and Odor substances with activated charcoal, specialist chlorination, etc. required are, the coagulation will support these operations significantly. .

In water treatment terminology, a coagulant is defined as an agent that is added to water to facilitate the settling of colloidal or finely divided suspended matter. Coagulation is the treatment process which refers to a series of chemical and mechanical treatments by which the coagulants themselves are applied and made effective. These operations are generally divided into two distinct phases, ie, a mixing operation is quickly dispersed into the coagulant dae dissolved within the water to be treated, usually accompanied by stirring and coagulation, which the stirring of the ^v -'assers at somewhat lower speeds over includes a much longer period of time during which the very small! particles grow and agglomerate into well-defined hydrated flakes of a size sufficient to promote rapid settling. The broad term clarification is generally used to encompass both coagulation and sedimentation or settling. In the context of the present invention, the water-soluble customary coagulants are defined as primary or "customary" coagulants.

The primary coagulants that are most widely used are aluminum or iron salts of either sulfuric or hydrochloric acid. Aluminum sulfate, Al ₂ (SO ₄ ), (sometimes referred to as PiIter alum) has been so far

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most of the Koagu agents used. Iron (II) sulfate, PeS0..7BpO (known as Vitriol) is also widely used. Bis (III) sulphate, Fe ₂ (SO _{4 I 5} (sometimes known as "Ferri-Floeke" or "Ferrisul"), iron (III) chloride, FeCl-'6HgO and Hatrlumaluminat, Na ₃ Al ₂ O ₄ , are also used as primary coagulants.

The chemical reactions that occur during coagulation occur are somewhat complex and include not only the direct association of the coagulating media with impurities in the water, but also the formation of water-containing ones Oxides. For example, the conversion of aluminum sulfate can be represented as follows «

Al ₂ (SO ₄ J ₅ XH ₂ O «• 3Ca (HCOj) ₂ > 3CaSO ₄ * • 2Al (OH) ₅ ♦ 600 _g + XHgO

This reaction equation shows that aluminum sulphate reacts with the naturally occurring alkalinity of water (called calcium bicarbonate, Ca (HCO ₅ ] I ₂ ). The hydrous oxide, Al (OH) ₅ , is bound around the flake ultimately fails and removes the unwanted contaminants from the water.

The amount of primary coagulant that is required to completely clearing water of turbidity varies widely from as little as 1 or 2 ppm to over 100 ppm.

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The exact amount of coagulating agent can normally only be determined by trial and error. Even so certain value varies with other factors, such as the time of the Mixing, the water temperature, etc. Pie minimum menu Coagulants determined to be used in manufacture good flocculation in a given water is effective, for example, it would generally be a fairly long mixing time varying from 15 to 30 minutes in summer and require from 30 to 60 minutes in winter when water temperatures approach freezing. A very finely divided one Suspended matter is more difficult to coagulate than the coarser particles, using a larger amount of coagulant is required for a given turbidity. The type of water also has a considerable influence on the pH, at which satisfactory flakes can be formed. In some types of water can be quite difficult to get good coagulation with alum at pH 7.5, whereas with other types of water, especially those that have a high calcium bicarbonate content, excellent Coagulation can be obtained at a pH ~ Vert of 8.5 or even higher. More generally it has been found that for natural Types of water have a pH adjustment against either the acidic or alkaline side of pH 7 is needed to be effective and obtain economical coagulation.

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Although ea is not necessary, the mechanism of flocculation To discuss in detail, 'should emphasize "ground" that in the promotion of the flattening of the flake particles flocculation both from the physical effect, in particular the agitation of the vase and the adhesion of the substances that cause the opacity, as well as depends on chemical or electronic forces that have a significant effect on the physical Have an effect. The physical action in the flocculation phase of coagulation is either mechanical Devices called flocculators or a system of Baffles in the mixing basin achieved, with the high mixing speeds can be gradually reduced to a point where the flake already formed in the mixing phase does not

torn or broken up, but kept in suspension. The coagulation period can vary from one system to another vary considerably. In general, the majority of water treatment plants operate with a 10 to 30 flint capacity Coagulation period, the broad range being 3 to 90 minutes amounts to.

Although many types of water require a more complex type of treatment, it is sometimes possible, was defined by the use of a single "usual" coagulant, such ea, to obtain a satisfactory flocculation. In the case of a number of substances that are not per se intended as coagulating agents

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can be seen, they have been found to have properties which the coagulant agent in fulfilling its Support puncture · These fabrics are known as coagulation lubricants. Generally speaking, alkalis, such as lime and soda sols, or acids such as sulfur, hydrogen chloride and phosphoric acid, can be regarded as coagulating agents. Sodium silicate, known as "activated silica gel", is partially neutralized with dilute sulfuric acid it is a coagulant aid.

In addition to the commonly used coagulants such as alum, vitriol, and the like, became certain high colloids Clays of the swelling bentonite type used for clarification. These species of xon are generally found near the Black lulle produced by Wyoming and South Dakota, and they are capable of making thick gels of multiple volumes of the original bentonite to form when water is added. They are sometimes referred to as "sodium lumbentonites" and their use to purify water is described in U.S. Patents 2,345,827 and 2 363 022 described in detail.

From the use of a bentonite-like clay and an organic polyelectrolyte as a coagulation aid emit t el, it is known that the coagulating effect of known coagulants increases will.

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In the USA-Batentβohrift J J38 828 of the "! Eichen Anttelderin a process is used to improve the flake formation of the βατ Mlsohvng a · permanent water-soluble inorganic coagulating ice and binding · an · organic polyelectro Iy tables Coagulation failure means low delivery of electrostatically precipitated gasoline to the agitated water is described. this leads to such a deceitful improvement) t> ei the floekenbildong in different kinds of water · This terbesserong Jedooh is not universal and does not cause any significant removal of phosphates from the water

In the present case it relates to the development of a process for the purification of drinking water, domestic use, for example. private sanitary sewage, aqueous industrial wastes and aqueous Process flow that is followed by the following stages. Show e of a primary water-soluble inorganic above coagulated nittele, an acid-treated plug ash and, if applicable ■ at least one organic po! Lyelectrolytic «! So xoagulant the water and listening to the mixture until a flake is formed, Absetsenlaseen the flake and recovery of the purified water.

The present invention further relates to the provision of a improved coagulating agent, using acid-treated fly ash

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Furthermore, the present invention relates to a new treatment of water and aqueous wastes in which an acid-treated β It β fly ash is used, with improved removal of flavors, phosphates, odorants and colors,

Furthermore, the present invention is also related to a new one Coagulation treatment method of water and aqueous bottling with more economical amounts of a coagulant medium and coagulant aids by using acid-treated Fly ash »

These and other objects of the present invention are provided in Im described below or are apparent from the following description.

The new inventive method sur clarification of water and aqueous wastes include the addition of a primary water-soluble inorganic coagulant and small amounts of for example, 1 to 250 ppm or more of an acid-treated one Fly ash to the water or aqueous wastes, thereby forming a floc, and separating the clarified "water" of this flake.

The amount of acid-treated fly ash used can be in Depending on the type of bu treated water or on it,

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which coagulating agents are also used, vary. Honestly, depending on the » pH value and the clarity of the au treating waterβ, of 2 to 30 ppm acid-treated fly ash 1 «general prevention.

The expression "acid-treated fly ash ¹ * used in the present application describes the acid-treated ash * residue that is recovered from combustion exhaust gas either through inertia devices such as cyclone separators or, preferably, cottrell" Precipitation or other electrostatic failure or electrostatically charged devices Burüok remains. This alkaline residue is contacted with a washing solution of a strong inorganic or strong organic acid such as sulfuric acid, hydrochloric acid, nitric acid, sulfamic acid, etc. for 1 to 60 minutes can vary from 1 1/2 to 100 pounds of the amount theoretically required to affect the metals present in the fly ash, and it is practically about twice that of the normal acid solution when treating a Veil F Use lug ash in · You can get sfture-treated fly ash from the acid treatment, inde » you load off the fly ash and then the acid-treated flight * ·

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ash dries at around 10 ⁰ G.

A particularly preferred office management form of the present invention comprises the use of an organic polyelectrolyte liquid coagulating agent together with the primary water-soluble inorganic coagulating agent and the treated fly ash. When these components are added to the clarifying water, stirred for 5 to 50 minutes and allowed to flocculate with slow stirring, an extremely heavy flake is quickly formed and immediately settles Turbidity from 90 i> to even 100 #, a reduction in the chemical oxygen demand (COB) and the biological oxygen demand (BOB) from 50 to 90 i> and an almost complete reduction in the Fboaphattwid polyphosphate ions in a single primary treatment stage.

The use of an organic, polyelectrolytic coagulation aid, together with the acid-treated according to the invention Fly ash leads to faster coagulation and greater flocculation results. For example, with the new invented

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. ingsgeraägen. Process the coagulation and the flakes »deposition azo it en can be reduced by more than 90 1» in comparison with the use of the coagulating agent alone or the coagulating agent and coagulating aid alone. This allows the treatment plant to be reduced in size and, conversely, increases the capacity of a treatment plant of a standard size and therefore reduces capital investment. Another advantage of the coagulating aid of the present invention is that less coagulating agent and organic polyelectrolyte are required, thereby reducing the cost of the treatment. Fly ash is usually a waste product and is therefore very cheap. The acid treatment adds only marginally to their costs. · '

The order of addition of the acid-treated fly ash, des organic polyelectrolytes and coagulant is not critical, and it can usually be done in any order. However, the best results are usually obtained when all of these products are around the corner be added at the same time.

Polyelectrolytes and the state of the art are in beet Handbook of Industrial Water Conditioning, 6th Edition, 1962, defined as follows: "Polyelectrolytes are water-soluble High molecular weight polymers containing groups

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which are able to "enter into electrolytic dissociation" or a highly charged ion of high molecular weight au. "Originally this expression was: single up synthetic polymers or copolymers applied «but it has now become more extensive through general use · The term now naturally includes organic ones that are dead Flocculants "many of which by hydration alone rather than acting through electrolytic activity. In some Cases the expression is based on the combination of natural organic flocculants and heavy inorganic (weighting) means applied

Poly electrolytes are further converted into anionic, cationic or non-ionic polyelectrons. Polymers «whose functional groups in water solution are positively charged particles sincere «are cationic. Polymers that dissociate to form negatively charged ions are called anionic. Polymers of the non-ionic group give in solution both * ' positive as well as negative charges.

The mechanism of the aids is not yet complete cleared up, however, many researches have been carried out to increase knowledge about their effects. Such factors " that the colloidal behavior as zeta potential, Brown's movement, Van der Waals' ache forces and electrophoretic movement

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Henkelt concern, are investigated, about a scientific treatment of the choice of X-oaguliermittel and Koagu-Ii he mean to determine. In the meantime, the most frequently questionable TTerkaeug stm finding out a system of coagulants is the well-known "wet test * (jar test) · ..

The application of the hoard toIyelektrolyte "in the description of the present invention refers to the broad definition given above from the Bets Handbook and the above extension to include inorganic polymeric coagulation auxiliaries such as activated silica gel.

Examples of suitable polyelectrolytes, the particularly Water-soluble cellulose derivatives such as hydroxyethyl cellulose, carboxymethyl cellulose, hydroxyethyl carboxymethyl cellulose, modified starches, starch ethers, are effective. Polysaccharides such as carrageenan, Guar Sun (öuaran), pectin, glue, water-soluble polyacrylamides, hydrolyzed «water-soluble Polyacrylamides with an average molecular weight of at least 10,000 polyethylene oxides, sulfonated, alkylaryl polymers with high molecular weights, such as sulfonated Polystyrene, etc.

The amount of the organic polyelectrolytic coagulating aid agent used in the process of the invention

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can be significantly above the normally recommended range can also be reduced. Amounts β as in 0.02 and 3.0 ppm are preferably used.

As stated above, the amount of the primary water-soluble inorganic coagulant can be reduced, otherwise, Io, substantially without affecting the severe and rapid formation of flakes. Comparable results are usually with 50 i> of Koaguliermitt normally used even in the presence of ice po "iy elektroIytischen Koagulierhilf smittels received.

In order to achieve optimal results, it has been found that the pH of the treated water, if acidic, increases should be set at 7. This is done with the help of lime reached with normally acidic types of water. In the case of alkaline water types, the adjustment of the pH value may not be necessary, since flake formation in the process according to the invention is easy in types of water with a pH value until 11 occurs. However, some control of the pH in strongly alkaline types of kegs can be achieved by using the acidic ones Stock solutions of the acid-treated fly ash are made *

Bas method can also be used in the treatment of drinking water supplies, such as rivers and ditches, water from industrial Waste and private waste and all other types of

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Water the clarification "" need to be carried out effectively "before use". Vorohlorierong or air treatment of the water before the treatment affects the knees in no catfish

The following examples illustrate the invention without it but restrict svt

example 1

Simultaneous examinations are carried out using τοη 1 Ilter- ^ water samples in laboratory pots. Kaoh addition of the coagulant, the acid treated fly ash and the organic poly elect ro Iy tables Koagu 11 help since tele are the size the formed flake and the side of the formation of the flake is determined. Comparison sets are also carried out. she Flake size is classified according to the following scale:

very small (sk) less than 1 ssi small (k) medium-small (ek) 1.9 m medium (■) 2 BM ■ Ittelgrofi (ng) 2.5 mn large (g) 3 BM very large (sg) larger than 3 m

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They'll be investigating at roll it yaaeer at the milestone River in the Eabe τοη Prinopton, New Jersey, carried out that an initial turbidity of 8.6 and a pH of 8.0 having. Because "Koagullermittel" is PeCl, and is used in a lot of 59 kg / 3785 hectoliters (130 lbe.per million gallons) (as Hydrate) used in all examinations. The results are given in Table I.

Chemical addition «
kg / 3785 hl (lbe.)
PeCl, CH. - 0.72 (1.6) Table I. Tempe
rature
⁰ C flake Turbidity of the
clarified
Passere vessel 59 (130) 59 (130) 0.32 (1.6) 0.36 (0.8) > in
Fly ash 17.5 sk 8.9 1 59 (130) 0.72 (1.6) - η k 6.1 2. 59 (130) - η η 6.4 3 59 (130) 45.3A (100) η η 7.1 4th 45.3A (100) N »Β 2.95 5 45.3B (100)

Bus KoagulierbilfsiDittel (CH.) Is Magnifloc 990, a polyacrylamide. Flugasohe Λ is an electrostatically precipitated fly ash, fly ash B an acid-treated fly ash Λ, treated with 3 £ of the theoretical amount of alcohol and dried at 105 ⁰ C was added · The haze is measured in Jackson units after sweimintitiger clarification · The various samples are 30 Seconds at 100 + tJpM, 30 seconds at 55 UpIf, 35 seconds at 32 UpII, 40 seconds at 30 RPM, 70 seconds at 20 RPH and

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40 seconds at 15 RPM «honoring a total of about four-piece« MIaoh en Temieoht «

The results add to the clear superiority of acid-treated fly ash in terms of flake formation and reduction the cloudiness.

Example 2

under the same conditions as in Example 1, a Other raw water has a pH of 7.35 and a turbidity of 7.8 due to the addition of chemicals over a temperature Taped for 20 minutesMe results are given in Table II

Table IX - 24.0 Floeke Final opacity .25 vessel Chenikallen addition in Teape-
kg / 3785 hl (lbs.) temperature
FeOl ₃ CH. Fly ash ⁰ O 0.72 (1.6) 45.3B (100) k 2 , 05 1 59 (130) 45.3B (100) 1 • 17th 2 59 (130) β 1 3 59 (130)

The lCoagulierhilfsmittel 1st Magnifloc® 990 and fly ash B is an electrostatically filled fly ash, the old $ 3> treated the theoretical amount of HCl and dried at 105 ⁰ O

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will·. In fihiftß 2 aetat it «lon immediately after the end of the * Stir "off, la Ooftifi Mst te" praise after "tv * for a minute and 6 «fli 1 needed 5 shrouds ni clarification.

Example 3

Electrostatic precipitated fly ash is old treats specified in Table III acids "inden nan the acid that is used in a concentration of about 35 i>, and long stirs the fly ash in a weight ratio of 2t1 30 minutes and then the mixture in a water bath introduced and cure dryness evaporated. Vessels containing various types of water and various aqueous wastes are then mixed with the chemicals listed in Table III for 20 minutes at 49 rpm and allowed to settle. The coogulating aid (CH *) 1st Drew floe Kr. 21. This material is a cationically nodulated starch. The values for lime and alum are given in kg / 3785 hl of water, and the fly ash, coagulant and sodium aluminate (AlO, +) in ppm.

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Table III

IO OO O OO

cn ο cn

Type of uraprüng
Water borrowed
Turbidity pH alum
kg / 3785 Chemicals
Lime acid
hl kg / 3785 hl treated
Fly ash
ppm 40 _χ
(HCl)
40
(HCl) AlO- +
PP » 8th CH.
ppe size
the
flake Volume
dull
exercise end
PH I.
IO Vinyl 208 6.4
plastic-
Washing water 59 (130)
68 (150) 25 (55)
29 (65) (H ₂ SO ₄ ) 8th
8th 8th 2
2 β
β 3.2
0.8 7.1
7.1 O
I. 54 (120) 23 (50) 40
(H ₂ SO ₄ ) 8th 8th 2 mg 1.0 7.1 63 (140) 27 (60) 8th 8th 2 mg 0.5 7.2 59 (130) 41 (90) 70 8
(SuIfamlneänre) 8th 2 β 1.3 7.3 63 (140) 45 (100) 80 2 8th 0.8 7.3 Steel - 41 6.3
drainage 63 (140) 27 (60) 40
(HCl) 2 β 0.9 7.2 water 73 (160) 29 (65) 40
(HCl) 2 β 0.6 7.3 54 (120) 25 (55) 40
(H ₂ SO ₄ ) 2 & 0.7 7.3 63 (140) 27 (60) 40
(H ₂ SO ₄ ) 2 β 0.3 7.2

CO N) CO CO

Example 4

The following study shows that the acid-treated fly ash of the present invention also reduces the amount of BOB and COD in raw sewage that has been air treated for 30 minutes of treatment and without any near-hollow treatment which further lowers the BOD and COB values. The wastewater showed an original turbidity of 165 », a COD value of 830 and a BOD value of? 60 and a zeta potential of -37 mV. Said wastewater is with 2 ppm CH. (Drew floe No. 21), 8 ppm AlO ^ +, 40 ppm acid treated fly ash and varying amounts of alum and lime mixed together in a mixer x at 45 vpm for 20 minutes. The wastewater is then allowed to settle for 30 minutes and the results are given in Table IV.

alum
kg / 3785 Table IV 159 (350) size
the
flake Band
turbidity pH BOD COD To Be
plot
of flight
ash ver
turned
acid lime
hl kg /
3785 hl 29 (65) β 43 11.0 60 197 68 (150lbs) 363 (800) G 44 9 90 415 HCl 118 (2SO) β 73 7th 100 186 127 (280)

68 (150) 363 (800) G 19th 11.0 75 121 H ₂ SO ₄ 118 (260) 136 (300) β 24 9 80 163 127 (280) 100 (215) G 71 7th 181 297

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This example explains how dleic acid-treated fly ash effectively aas all of the phosphate components can remove aqueous solutions, and demonstrates the superior displaceability of acid-treated fly ash in comparison au the same untreated fly ash. Raw wastewater treated to achieve a pH of 11.2 with a turbidity of 187 · a COD value of 615 and total phoaphate of 8.3 ppm is 20 minutes with the chemicals listed in Table Y. stirred at 415 tPM and then sit for 30 minutes The fly ash used is mixed with hydrochloric acid in a weight ratio of 2t1 for 5 minutes, and the resulting slurry is mixed with water to form a Vorratalöaung containing 12 g of fly ash per liter of solution, diluted, the CH * is Drew floe ITr.21 »

40 - V 6 (8) CH,
ppm 2? Back
.exercise PO ₄ COD colour 40 6th 3 3.0 0.2 205 20th Tabel 100 - AlO- +
kg / ³
3785 hl 6th 3 1i5 0.1 200 20th Chemicals
FeCl, lime fly ash-none
kg / kg / acid acid
3785 hl 3785 hl ppm ppm 100 - 3, 6th 3 2.0 0.1 180 10 9 (20) 997 (2190) 100 3, 6th 3 1.0 0.1 120 10 18 (40) 1050 (2320) - 40 3, 6th 3 0.8 0.1 95 10 9 (20) 997 (2190) - 40 3, 6th 3 7.0 0.5 241 30th 18 (40) 1088 (2400) 100 3 _t 6th 3 6.0 0.5 250 30th 27 (60) 1150 (2550) 100 3, 6th 3 6.0 0.4 235 20th 9 (20) 1179 (2600) - 100 3, 6th 3 5.0 0.4 230 20 * 18 (40) 1179 (2600) 3, 3 4.0 0.35 225 20th 9 (20) 1179 (2600) 3, 18 (40) 1179 (2600) 3, 27 (60) 1200 (2680)

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Example 6

This example demonstrates that the acid-treated fly ash erfindungegemafie phosphates from the water over a wide pH range of the water removed, while the gleiohe fly ash without acid treatment only effective at a high pH phosphates ^r / ert removed. The water used in this study is water from the Delaware River with a pH of 6.8 and a content of ^ -phosphates of 0.35 ppm and 50 to 1 ppm metaphosphate · base and the chemicals listed in Table VI are 20 Stirred minutes at 45 QpH, and then the water is allowed to settle for 30 minutes.

Table YI

alum

Chemicals lime Na ₂ AlU ₃

CH. acid
Fly ash

Untreated fly ash

pH ppm

Ortho »phosphate

ppm

Metapbos "

phat

113 (250) 453 (1000) 453 (1000) 3.6 3 50 - 11.2 0.02 0.03 113 408 (900) 3.6 3 100 11.2 0.01 0.02 113 408 (900) 3.6 3 150 - 10.0 0.000 0.004 113 362 (800) 3.6 3 200 - 9.0 0.000 0.001 113 340 (750) 3.6 3 250 8.5 0.000 0.001 11? 453 (1000) ? f6 ? 300 «. 8.0 0,000 0.001 113 453 (1000) 3.6 3 - 50 11.2 0.05 0.24 113 408 (900) 3.6 3 - 100 11.2 0.025 0.24 113 408 (900) 3.6 3 150 10.0 0.3 0.42 113 362 (800) 3.6 3 - 200 9.0 0.35 113 340 (750) 3.6 3 - 250 8.5 0.35 3.6 113 3.6 300 8.0 0 _for 5

2 0 B 8 0 0/1 b U δ

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The alum, the lime and the Hatrlunaluminat "earth in kg / 3785 hl. The coagulation aid (CH.) Iet "Λ-21", a high molecular weight alkylarylsalphonic acid and is added in an amount of 3 PP ». The fly ash and acid-treated fly ash are given in ppm.

Table YI shows that the acid-treated fly ash effectively removes all phosphate levels over a wide alkaline range removed, while untreated fly ash removes phosphate content only at a high pH value of fiber 11 and not like that is effective. The removal of phosphates from water sources is important as high levels of phosphates encourage the growth of Algae in natural waterways like that of the Oreat Lakes, raise.

As indicated above, acid-treated fly ash, preferably electrostatically precipitated fly ash, in the purification and clarification of water from various sources be used. This ingredient is mixed with a primary water-soluble inorganic coagulant and optionally with an organic polyelectrolytic coagulation aid used. The various chemicals can be added to the water to be treated in any order and in the specified Quantities are added.

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Various compositions of primary water-soluble inorganic coagulants and acid-treated fly ash with, if necessary, an organic polyelectrolyte coagulant can also be used, especially in smaller areas Plants for water treatment, are manufactured «Such

For example, compositions can consist of from about 15 to

75 about / wt .- # of a primary water-soluble inorganic Coagulant, about 10 to about 50 weight percent, acid treated Fly ash, from 0 to about 5% by weight of an organic polyelectro-Iy table coagulating aid and from 0 to about 70 people. ™ Lime

The use of acid-treated fly ash is, as shown above, for the tertiary treatment of wastewater and industrial waste, in particular for the removal of phosphates and polyphosphates ^ and organic and inorganic materials which are difficult to remove and which largely pass through the usual plants for the treatment of wastewater without being removed , of great importance. m

The very high BOB and COD distances achieved using acid treated fly ash are much higher than that which is calibrated with similar wastewater and industrial waste using the latest organic polyelectrolyte and other coagulant systems, a

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finally some of the coagulant auxiliaries used in the examples mentioned above. Bs is therefore obvious that the use of acid-treated fly ash as \ bsorbent is much more effective than that of others Materials currently in use. As shown in the examples, it is also much more effective than that, using untreated fly ash.

Various modifications of the compositions and of the

Process according to the invention can be carried out as

under for example / using a very strong inorganic Acid instead of the specifics given in the examples Acids without changing the essentials and such modifications are also within the scope of the present invention.

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Claims (1)

Γ - 27 - Fat en taneprUche 1. A process for the clarification of drinking water supplies, aqueous waste and aqueous Yerfahrenθatromen by contacting this water with a primary water-soluble inorganic Xoaguliermittel to form a flake and separation of the water from this flake, characterized in that together with this Koaguliermittel ™ 1 to 250 ppm, based on the water quantity β, with 3 to 100 f » the theoretical amount of strong acid treated fly ash is used. 2. The method according to claim 1, characterized in that the fly ash is an electrostatically precipitated fly ash. 3 · The method according to claim 1, characterized in that the amount of the acid-treated fly ash is 3 to 100 ppm · m 4. The method according to claim 1, characterized in that an organic polyelectrolytic coagulating aid is also used. 5. The method according to claim 1, characterized in that the fly ash is treated with a strong mineral acid. 209808/1505 ßAD 6. Process sar purification τοη drinking water, private « sanitary sewage, aqueous industrial wastes and aqueous process flows, characterized in that the steps of adding a primary water-soluble inorganic coagulant, at least one organic polyelectrolytic coagulant and acid-treated Fly ash to the water, stirring the mixture until a flake is formed »allow the flake to settle and profit purified water include 7. The method according to claim 6, characterized in that the water for up to 50 minutes before adding the coagulant old air was treated. 8. Process for clarifying water, the dissolved * suspended and contains colloidal substances and simultaneous removal τοη Phosphate fractions from it, characterized in that the Water with an effective amount of a water-soluble inorganic coagulant agent, at least 0.01 ppm of an organic one Polyelectrolyte, which is able to absorb the outflow rate and the capacity of the water-soluble coagulant β and do absorb this dissolved, suspended and colloidal material and with about 1 to 250 ppm acid-treated fly ash one to form a Flake contacted for a sufficient period of time and from this flake 209808/1505 ⁰⁴⁰ a purified water with less than 0.01 ppn of phosphate parts separates · ■ ^:. ■. - · 9. Procedure for removing iron phosphate fractions from water » that contains this, that the contact with this water an alkaline earth ion source and separation of the precipitate comprises, characterized in that «to the water with a source of alkaline earth ions with 1 to 250 ppm acid-treated Contacted Plugaaohe. 10. Procedure for removing phosphate from the Water containing these, characterized in that the water is contacted with from 1 to 250 ppm acid-treated plug ash, the precipitate is separated off and water with significantly reduced phosphate content is obtained. 11o procedure Eur purification of drinking water, private sanitary wastewater, aqueous industrial waste and aqueous process streams, characterized by the following, the stages: addition of at least one organic poly » electrolyte and acid-treated plug ash to the water, Stir the mixture until a flake is formed, allow the plooke to settle and recover the purified water. BAD ORIGINAL 209808/1505 ⁸ ^ 12. Association for the application in the case of the handlong and Clarification of water, which is essential also from about O to about 75% by weight of a primary water dissolver / coagulant, of about 10 to about 95% by weight of acid chandelier Fly ash, from 0 to about 10% by weight of an organic poXy electrolyte pool coagulating aid and ron 0 to about 70 uew.-9t lime consists 209808/1505