KR102093994B1 - Preparation method of low basicity coagulant using strong acid hypochlorite water and water treatment method using same - Google Patents

Abstract

The present invention relates to a coagulant for water purification and sewage·wastewater treatment and, more specifically, to a method for manufacturing a water treatment coagulant with oxidizing power of low basicity using strong acid hypochlorite water, and a water treatment method using the same. According to the present invention, the method for manufacturing a low basicity coagulant using strong acid hypochlorite water comprises: a first step of generating polyaluminum chloride (PAC) containing 15 to 20 wt% of aluminum oxide (Al_2O_3) generated by reacting aluminum hydroxide (Al(OH)_3) with hydrochloric acid (HCl); and a second step of adding and reacting aluminum sulfate, which is a first basicity modifier, to and with the PAC, and adding and reacting strong acid hypochlorite water, which is a second basicity modifier, to and with the mixture to manufacture a hypochlorous polyaluminum chlorosulfate (HCPACS) coagulant having the basicity of 5 to 25% and the remaining chlorine of 0.02 to 2 mg/L, represented by Al_2(OH)_aCl_b(SO_4)_c(OCl)_d.

Description

Preparation method of low basicity coagulant using strong acidic hypochlorous acid water and water treatment method using the same {Preparation method of low basicity coagulant using strong acid hypochlorite water and water treatment method using same}

The present invention relates to a method for producing a coagulant for water purification and sewage and wastewater treatment, and more particularly, to a method for preparing a water treatment coagulant having oxidizing power of a low basic airway using strong acidic hypochlorous acid water and a water treatment method using the same.

In the treatment of purified water and sewage and waste water, the flocculation and precipitation treatment is the most basic process. At this time, the organic substances contained in the raw water are precipitated together to reduce the chemical oxygen demand (COD) or biological oxygen demand (BOD) in the water. The use of coagulants is essential, and the coagulants used at this time are aluminum sulfate (hereinafter referred to as 'Alum') and polymer polyaluminium chloride (hereinafter referred to as 'PAC'). .

Recently, several types of products with additives and basicity modifiers added to inorganic coagulants Alum and PAC have been developed and sold on the market, but Alum and PAC are still the most used for water purification, sewage, and wastewater treatment.

In particular, PAC usage has been rapidly increasing in sewage treatment plants in recent years, but PAC for tap water by the 'drinking water management method' has high basicity, so it has an excellent effect on low turbidity and low water temperature, but it is effective in treating high turbidity and high concentration COD like sewage and wastewater. Due to its limitations, the development of low-base PACs is increasing.

Although high water bases have recently been changed to PAC products in water purification plants across the country that purify water with low turbidity and low water temperature, Nakdong River raw water and sewage water have high cohesive properties for suspended solids and particulate matter due to high charge neutralization by alkaline metal salts. It is difficult to remove COD due to weak reactivity with organic substances dissolved in raw water. In addition, when the excess amount is added, the residual aluminum concentration increases due to the reversal of the precipitate. On the contrary, the low-base PAC can achieve a high COD reduction effect by adsorbing and co-precipitating organic matter by microfloc production.

As the COD concentration increases, the amount of the fine floc increases as the amount of the inorganic flocculant increases, so the turbidity of the treated water increases when a sufficient sedimentation time is not given. Therefore, there is a need to develop a new coagulant with excellent COD reduction efficiency, sedimentation and removal of fine floating matter.

Water treatment flocculants are 1 (10.0 to 12.0%), 2 (12.0 to 15.0%) depending on the aluminum oxide content in the “Standards and Specifications and Labeling Standards for Water Treatment Agents” No. 2017-190 (2017. 10. 23.) ), 3 types (15.0 ~ 18.0%), and basicity is defined as more than 35%. It is used for waterworks and sewage treatment plants through government procurement.

In the prior art, Patent Document 1, in a method for stably producing a low-aluminum polyaluminum chloride-based coagulant, prepares an aluminum chloride having an extremely low-aqueous base (0 to 3%) obtained by the reaction of aluminum hydroxide and an acid, and again increases the basicity. As a zero agent, it discloses a configuration for preparing a polyaluminum chloride-based flocculant having a low basicity (5-25%) level by reacting with a mixture of magnesium hydroxide and calcium hydroxide, and adding low hydrochloric acid to produce a low-base PAC. It has the characteristics of a one-step reaction to prepare a base PAC.

In addition, Patent Document 2 is a primary reactant that is polyaluminum chloride (PAC) whose Al ₂ O ₃ content is adjusted to 15-18% by reacting for 5-10 hours at a temperature of 120-170 ° C. by adding aluminum hydroxide and hydrochloric acid. It relates to producing a low-base polyaluminum chloride (PACB) consisting of a step of reacting hydrochloric acid with a primary reactant and a basicity modifier, and in the production of low-base PAC, general PAC is prepared and then hydrochloric acid is produced. It is characterized by a two-step reaction that reacts in addition.

Patent Document 1. Republic of Korea Registered Patent Publication No. 10-1752777 Patent Document 2. Republic of Korea Registered Patent Publication No. 10-1159236

The present invention devised to solve the problems of the prior art as described above, the content of Al ₂ O _{3 as} a flocculant that maintains a low salt airway is 10.0 to 16.0 wt%, basicity is 5 to 25%, residual chlorine is 0.02 to 2 mg / It is an object to prepare a polyaluminum hypochlorite (HCPACS) coagulant which is ℓ.

That is, the inorganic coagulant with improved COD reduction efficiency by coagulation removal efficiency and oxidizing power for suspended solids (suspension particles) than conventional PAC, low-base, and high-base PAC using Alum and strong acidic hypochlorous acid water, storage stability It is an object of the present invention to produce a polyaluminum hypochlorite flocculant having a low basicity.

In order to achieve the above object, a method of preparing a low-base air cohesive agent using strong acidic hypochlorous acid water of the present invention, aluminum oxide (Al ₂ O ₃ ) produced by reacting aluminum hydroxide (Al (OH) ₃ ) with hydrochloric acid (Hcl) ) The first step of producing a polyaluminum chloride (PAC) content of 15 to 20% by weight; After the reaction by the addition of a primary basicity adjusting agent is aluminum sulfate (Aluminium sulfate) to said poly aluminum chloride, secondary basicity adjusting agent is to put the reaction the number of strong acid difference chlorate, aluminum (Al ₂ O ₃₎ content of 10.0 to oxidation 16.0% by weight, basicity of 5 to 25%, residual chlorine is 0.02 to 2mg / ℓ, hypochlorous acid polyaluminum sulfate represented by [Formula 1] ((Hypochlorous PolyAluminium Chloro Sulfate, HCPACS) flocculant preparation agent Step 2: Al ₂ (OH) _a cl _b (SO4) _c (Ocl) It comprises a _d .

In addition, in [Formula 1], a + b + c + d = 6, and the range is 0.3≤a≤1.5, 4.2≤b≤5.6, 0.1≤c≤0.3, 0.000002≤d≤0.0002) do.

In addition, the polyaluminum chloride in the first step is stirred at 150 to 160 ° C. while stirring 2 mol of solid aluminum hydroxide (purity of 99.5% or more, and 3.6 mol of hydrochloric acid (Hcl 30 to 35%)) at 58 to 120 rpm. After producing PAC having an Al ₂ O ₃ content of 18 to 20% by weight by reacting for ~ 6 hours, dilution water was added thereto, and the Al ₂ O ₃ content was 16.10% by weight and the basicity was 35.0 to 45.0%. do.

In addition, the primary basicity regulator of the second step is 100 to 130 ° C. while stirring 2 moles of solid aluminum hydroxide (purity of 99.5% or more, 3 moles of sulfuric acid (H ₂ SO ₄ 98%)) at 58 to 120 rpm. It is characterized in that the aluminum oxide content produced by reacting at 1 to 3 hours is 8.0% by weight and the basicity is 0% aluminum sulfate.

In addition, the secondary basicity regulator of the second step is prepared by stirring and reacting hydrochloric acid (Hcl 35%) in a mixed solution of sodium hypochlorite and water, or as an insoluble electrode in a solution of water and hydrochloric acid (Hcl 35%). It is characterized in that the residual chlorine amount is 0.5 to 150 mg / L concentration by applying a DC voltage (1.6 V) and a current (1 A) in the configured electrolyzer.

In addition, in the first step, the content of Al ₂ O ₃ generated by reacting aluminum hydroxide (Al (OH) ₃ ) and hydrochloric acid (Hcl) in a high-temperature high-pressure reactor at 150 to 160 ° C. for 3 to 6 hours is 15 ~. 20 weight%, a step of preparing polyaluminum chloride having a basicity of 35.0 to 45.0%, and in the second step, 0.1 to 60 to 100 ° C temperature condition while stirring by adding aluminum sulfate having 0% basicity as the primary basicity regulator. After reacting for ~ 1 hour, the strong acidic hypochlorous acid water having 0% basicity, which is the secondary basicity regulator, was added to react for 0.1 to 1 hour at a temperature condition of 60 to 100 ° C, and the Al ₂ O ₃ content was 10.0 to 16.0. A method for producing a low-base flocculant using strong acidic hypochlorous acid water, which is characterized in that it is a step for preparing polyaluminum hypochlorite having a weight%, basicity of 5 to 25%, and residual chlorine of 0.02 to 2 mg / l.

In addition, it characterized by a method for treating purified water or sewage, wastewater by using a coagulant with a low base also using the strong acidic hypochlorous acid water of the present invention.

The basicity of the inorganic coagulant is a molar concentration ratio of OH ^- ions to Al ³⁺ ions, '[OH] / [Al] * 3) * 100', and the basicity value is 0 to 100%.

The primary basicity adjusting agent according to the present invention is used to control the storage stability and basicity of PAC by sulfates, and may use sulfates such as sodium, magnesium, iron, and rare earth metals as well as Alum, especially sodium sulfate, magnesium sulfate, and iron sulfate , It is also possible to select one or more, such as lanthanum sulfate.

Therefore, according to the method for preparing a low-base coagulant using strong acidic hypochlorous acid water and the water treatment method using the same, the efficiency and oxidizing power of flocculation for suspended substances (suspension particles) than conventional PAC, low-base, and high-base PAC Alum and strong acidic hypochlorous acid water were used in manufacturing the inorganic coagulant with improved COD reduction efficiency. Therefore, it is possible to prepare a polyaluminum hypochlorite coagulant of low basicity with storage stability.

The HCPACS manufactured according to the manufacturing method of the present invention is an inorganic coagulant having both a low basicity and an oxidizing power, and has excellent floating material removal and sedimentation properties, and has the effect of maintaining product stability that does not generate hydroxide by dissociating during long-term storage.

In addition, it has excellent characteristics in reducing the amount of sludge generated due to the reduction in the amount of water used in the treatment of purified water and sewage and waste water, and removing suspended matter and organic matter (COD) in water.

The effects obtainable in the present invention are not limited to the above-mentioned effects, and other effects not mentioned will be clearly understood by those skilled in the art from the following description. .

Included as part of the detailed description to aid understanding of the present invention, the accompanying drawings provide embodiments of the present invention and describe the technical features of the present invention together with the detailed description.
1 is a graph showing a change in turbidity according to the amount of coagulant input of the present invention based on the number of raw water in a water treatment plant.
Figure 2 is a graph showing the change in UV254 according to the amount of coagulant input of the present invention based on the number of raw water.
Figure 3 is a graph showing the change in COD according to the amount of coagulant input of the present invention based on the number of raw water.
4 is a graph showing the change in turbidity according to the amount of coagulant input of the present invention based on raw sewage.
5 is a graph showing UV254 change according to the amount of coagulant input of the present invention based on raw sewage.
6 is a graph showing the change in COD according to the amount of coagulant input of the present invention based on raw sewage.

The terms or words used in the specification and claims should not be interpreted as being limited to ordinary or lexical meanings, and the inventor can appropriately define the concept of terms in order to explain his or her invention in the best way. Based on the principle that it should be interpreted as meanings and concepts consistent with the technical spirit of the present invention.

Therefore, the embodiments shown in the embodiments and the drawings described in this specification are only the most preferred embodiments of the present invention and do not represent all of the technical spirit of the present invention. It should be understood that there may be equivalents and variations.

Unless otherwise defined, all terms (including technical and scientific terms) used in the present specification may be used as meanings commonly understood by those skilled in the art to which the present invention pertains. In addition, terms defined in the commonly used dictionary are not ideally or excessively interpreted unless specifically defined.

In this specification, the terms "comprises" or "have" are intended to indicate the presence of features, numbers, steps, actions, components, parts or combinations thereof described in the specification, one or more other features. It should be understood that the existence or addition possibilities of fields or numbers, steps, operations, components, parts or combinations thereof are not excluded in advance.

With reference to the accompanying drawings will be described in detail an embodiment of a method for producing a low-base coagulant and a water treatment method using the strong acidic hypochlorous acid water of the present invention. In describing the present invention, detailed descriptions of related known functions or configurations are omitted so as not to obscure the subject matter of the present invention.

Hereinafter, the present invention will be described in more detail through examples and comparative examples, and the following examples are not intended to limit the present invention.

<Example 1>

(a) Al ₂ O ₃ content 16% PAC production

3,936Kg of solid aluminum hydroxide (Al (OH) ₃ , purity 99.5% or higher, dry phase) and 9,792Kg of hydrochloric acid (Hcl 35%) were added to a glass reactor stirred at 60 rpm, and reacted at about 155 ° C for 4 hours to produce aluminum oxide Al _{After 2} O ₃ content of 18.6 wt% PAC was prepared, 2,272 Kg of dilution water was added thereto to prepare 16,000 Kg of PAC having an Al ₂ O ₃ content of 16.10 wt% and basicity of 38.5%.

(b) Al ₂ O ₃ content 8% Alum production

120 g of solid aluminum hydroxide (Al (OH) ₃ , purity 99.5% or higher, dry phase) was mixed with 200 g of water in a glass reactor stirred at 100 rpm, and then 240 g of sulfuric acid (H ₂ SO ₄ 98%) was added and then at about 105 ° C. After reacting for 2 hours, when it became transparent, 440 g of water was added to prepare 1000 g of Alum having an Al ₂ O ₃ content of 8.0% by weight and 0% basicity.

(c1) Preparation of strongly acidic hypochlorous acid water

1 g of sodium hypochlorite (12% of effective chlorine) was mixed with 387 g of water and 612 g of hydrochloric acid (Hcl, 35%) was reacted at 100 rpm for 0.5 hour to react for 0.5 hour with Hcl 21%, residual chlorine 130 mg / L and strong acidic hypochlorous acid 1000 g Was prepared.

(c2) Preparation of strongly acidic hypochlorous acid water

In the electrolytic cell composed of an insoluble electrode in a solution of 612 g of water and 612 g of hydrochloric acid (Hcl, 35%), DC voltage (1.6 V) and current (1 A) were applied for 15 minutes in the electrolytic cell, and the residual chlorine content was Hcl 21% and residual chlorine 0.76 mg / 1000 g of strong acidic hypochlorous acid at a concentration of ℓ was prepared.

[A] Manufacture of PAC (Sample 1)

The Al ₂ O ₃ content 16.1% PAC 600g made in (a) and the Al ₂ O ₃ content 8% Alum 100g made in (b) were reacted for 1 hour under mixing conditions of 70 ° C and 120 rpm, and then 300g of water was added. By reacting for 0.5 hour, 1000 g of PAC having an Al ₂ O ₃ content of 10.46% by weight and a basicity of 35.36% was prepared (sample 1, water treatment standard PAC type 1).

[B] Manufacture of low-base PAC (Sample 2)

Al ₂ O ₃ content made in (a) 16.1% PAC 650 g of hydrochloric acid 35% 180 g and water 170 g of the mixed solution was reacted for 1 hour at a mixing condition of 70 ℃ and 120 rpm Al ₂ O ₃ content is 10.58% by weight, basicity A low base PAC of 10.58% was prepared 1000g (sample 2).

[C1] HCPACS (Sample 3-1) Preparation

The Al ₂ O ₃ content 16.1% PAC 600g made in (a) and the Al ₂ O ₃ content 8% Alum 100g made in (b) were reacted for 1 hour at a mixing condition of 90 ° C and 120 rpm, and then (c1). 300 g of strong acidic hypochlorous acid was added to react for 1 hour to prepare 1000 g of PAC having an Al ₂ O ₃ content of 10.54% by weight, a basicity of 7.81%, and residual chlorine of 0.07 mg / L (Sample 3-1).

[C2] HCPACS (Sample 3-2) Preparation

The Al ₂ O ₃ content 16.1% PAC 600g made in (a) and the Al ₂ O ₃ content 8% Alum 100g made in (b) were reacted for 1 hour at a mixing condition of 90 ° C and 120 rpm. 300 g of strongly acidic hypochlorous acid water prepared in (c2) was added and reacted for 1 hour to prepare 1000 g of PAC having an Al ₂ O ₃ content of 10.55% by weight, basicity of 7.80%, and residual chlorine of 0.07 mg / L (sample 3-2). .

<Test Example 1>

For the stability test of the samples prepared in <Example 1>, the results for freezing temperature and storage safety are shown in Table 1 below.

Comparison of freezing temperature and storage stability Item PAC (sample 1) Low base PAC (sample 2) HCPAC (sample 3-1) HCPAC (sample 3-2) Freezing temperature (℃) -31 -31 -33 -33 Storage stability (6 months) No change in properties No change in properties No change in properties No change in properties

In order to test the coagulation characteristics of HCPACS prepared in <Example 1> for water purification and sewage treatment, Nakdong Gangwonsu (hereinafter referred to as 'Nakdong Gangwonsu') and Ulsan Onsan Sewage Treatment Plant (hereinafter referred to as 'Onsan Sewage') ) Was collected and a cohesion experiment was conducted using a Jar-test.

The Jar-tester used in the cohesive tester is equipped with six stirring devices. The size of the paddle is 20mmH × 76mmL, and it is a device that can control the stirring speed. In addition, the Jar used for the coagulation experiment used a 1 liter beaker.

In the Jar-Test conditions, the stirring speed and the stirring time were set to 150 rpm and 50 rpm, respectively, and the stirring time was set to 1 min and 30 min, respectively under rapid and slow stirring conditions. After 30 minutes of standing, it was collected at a point 10 cm below the surface of the water to analyze the treated water.

The concentration of organic substances present in water was confirmed by the UV-254nm measurement value, which is commonly used to indirectly measure the state of change of COD and organic substances, and the water quality analysis in the aggregation test was performed using standard methods (AWWA, 2005), manufactured substances. The analysis method of was in accordance with the Ministry of Environment Notice No. 2017-190 (October 23, 2017) “Standards and standards for water treatment and labeling standards”, and the analyzers used are shown in [Table 2] below.

Instrument used for analysis Item unit Analyzer name Jar-test Jar-tester (chang shin scientific, Model C-JT) pH pH Meter (Toa, Model HM-31P) Turbidity NTU Tubidity meter (Humas, Model Tubby 1000) COD ppm Water quality analyzer (Humas, Model HS2300 plus) UV254 cm ^-1 UV-VIS Spectrometer (PG instruments, Model T60) Chlorine ppm Colorimeter (Lamotte, Model 1200-CL)

And the coagulant used in the coagulation experiment was used in the <Example 1> PAC (Sample 1) and low base PAC (Sample 2) and HCPAC (Sample 3-1, Sample 3-2) prepared according to the present invention. , Water treatment agents commonly used to treat raw water from water purification plants and raw water from sewage treatment plants are PAC (sample 1) and low-base PAC (sample 2), so HCPAC (sample 3-1, sample 3) of the present invention is based on this. Compared to -2), the results of the cohesive efficiency are shown in [Table 3] and [Table 4] below as a cohesive characteristic according to each input amount.

As shown in the flocculation efficiency according to the flocculant input amount of each flocculant used in the flocculation experiments of [Table 3] and [Table 4], in the case of HCPAC (Sample 3-1, Sample 3-2) according to the present invention, PAC ( 10%) and low-base PAC (10%), it showed excellent effect in removing suspended matter and organic matter (COD) in water.

Water Purification Plant Raw Water (Nakdong River Raw Water) Comparison Test Results Coagulant type input
(ppm) Turbidity
(NTU) UV254
(cm ^-1 ) COD
(ppm) pH ORP
(mV) Nakdong Gangwon-su 0 16.7 0.084 3.28 7.72 182 PAC
(Sample 1) 10 12.8 0.079 2.42 7.64 213 15 7.2 0.058 1.58 7.54 223 20 0.7 0.036 0.73 7.45 234 25 0.5 0.034 0.68 7.35 221 30 0.4 0.032 0.64 7.24 207 35 0.2 0.030 0.59 7.14 194 Low base PAC
(Sample 2) 10 12.4 0.078 2.02 7.62 213 15 6.8 0.057 1.35 7.54 222 20 0.6 0.035 0.69 7.43 232 25 0.5 0.034 0.65 7.30 219 30 0.4 0.032 0.62 7.16 206 35 0.3 0.030 0.58 7.02 194 HCPAC
(Sample 3-1) 10 11.1 0.076 1.88 7.62 217 15 5.7 0.054 1.24 7.53 227 20 0.4 0.032 0.61 7.42 237 25 0.4 0.031 0.59 7.29 224 30 0.3 0.030 0.58 7.15 212 35 0.2 0.029 0.56 7.02 199 HCPAC
(Sample 3-2) 10 11.2 0.076 1.89 7.62 195 15 5.7 0.054 1.26 7.52 218 20 0.4 0.032 0.62 7.43 227 25 0.4 0.031 0.59 7.30 238 30 0.3 0.030 0.58 7.16 225 35 0.2 0.029 0.57 7.03 211

1 to 3 is a graph showing the change in turbidity, UV254, and COD according to the amount of the coagulant in the present invention in [Table 3], which is a test result based on the raw water of the water purification plant according to <Test Example 1>. .

Sewage treatment plant raw water (onsan sewage) test results Coagulant type input
(ppm) Turbidity
(NTU) UV254
(cm ^-1 ) COD
(ppm) pH ORP
(mV) Onsan Sewage 0 3.9 0.215 38.01 7.61 81 PAC
(Sample 1) 10 1.4 0.214 30.67 7.58 97 20 1.3 0.204 27.58 7.56 98 40 1.2 0.184 21.40 7.52 102 60 1.1 0.181 20.88 7.47 106 80 1.1 0.178 20.35 7.44 109 100 1.0 0.175 19.84 7.37 113 Low base PAC
(Sample 2) 10 1.4 0.213 28.97 7.55 100 20 1.3 0.203 26.30 7.52 102 40 1.1 0.182 21.01 7.47 106 60 1.0 0.179 20.33 7.41 111 80 1.0 0.176 19.68 7.34 117 100 1.0 0.173 19.01 7.28 122 HCPAC
(Sample 3-1) 10 1.3 0.213 27.83 7.54 102 20 1.2 0.201 24.28 7.51 105 40 1.0 0.178 20.27 7.46 110 60 1.0 0.175 19.65 7.40 115 80 0.9 0.174 18.99 7.33 119 100 0.9 0.173 18.70 7.27 124 HCPAC
(Sample 3-2) 10 1.3 0.213 27.79 7.54 103 20 1.2 0.201 24.25 7.50 105 40 1.0 0.178 20.26 7.45 110 60 1.0 0.176 19.63 7.40 114 80 0.9 0.174 18.98 7.32 118 100 0.9 0.173 18.71 7.27 124

4 to 6 is a result of testing based on Onsan Sewage, which is the raw water of a sewage treatment plant according to <Test Example 1>, in Table 4, turbidity change, UV254 change, and COD change according to the coagulant input amount of the present invention, respectively. It is shown.

<Test Example 2>

In order to examine the reaction temperature characteristics of HCPAC, the results of cohesive performance test of the results prepared by different reaction temperatures under the same conditions are shown in [Table 5].

As shown in the flocculation efficiency according to the flocculant input amount of each flocculant used in the flocculation experiment of [Table 5], reacting at 100 ° C showed the best effect.

Cohesion performance test results according to the reaction temperature of the coagulant of the present invention Coagulant type Reaction temperature
(℃) input
(ppm) Turbidity
(NTU) UV254
(cm ^-1 ) COD
(ppm) pH ORP
(mV) Hwamyeong Water Purification Plant - 0 16.7 0.084 3.28 7.72 182 HCPAC
(Sample 3-1) 25 20 0.604 0.044 0.72 7.44 235 50 20 0.512 0.040 0.67 7.43 236 75 20 0.464 0.037 0.65 7.43 236 100 20 0.382 0.032 0.61 7.42 237 HCPAC
(Sample 3-2) 25 20 0.601 0.044 0.74 7.44 236 50 20 0.511 0.040 0.68 7.44 236 75 20 0.462 0.037 0.67 7.43 237 100 20 0.378 0.032 0.62 7.42 238 Coagulant type Reaction temperature
(℃) input
(ppm) Turbidity
(NTU) UV254
(cm ^-1 ) COD
(ppm) pH ORP
(mV) Onsan sewage raw water - 0 3.942 0.215 38.01 7.61 81 HCPAC
(Sample 3-1) 25 40 1.122 0.182 22.13 7.48 108 50 40 1.077 0.181 21.84 7.48 109 75 40 1.042 0.179 21.17 7.47 109 100 40 0.981 0.178 20.27 7.46 110 HCPAC
(Sample 3-2) 25 40 1.118 0.182 22.12 7.48 108 50 40 1.074 0.181 21.81 7.48 109 75 40 1.037 0.179 21.14 7.46 109 100 40 0.979 0.178 20.26 7.45 110

In the process of adjusting the low base in the present invention, the reaction temperature is preferably 100 ° C., and the HCPAC (Sample 3-1, Sample 3-2) of the present invention in the aggregation test is the PAC (Sample 1) and the low base PAC (Sample). Compared to 2), it showed excellent effect in removing suspended matter and organic matter (COD) in water.

The present invention has been shown and described with reference to preferred embodiments as described above, but is not limited to the above-described embodiments and is within the scope of the present invention to those skilled in the art to which the present invention pertains. By doing so, various changes and modifications will be possible.

Claims (7)

A first step of producing polyaluminum chloride (PAC) having an aluminum oxide (Al ₂ O ₃ ) content of 15 to 20% by weight by reacting aluminum hydroxide (Al (OH) ₃ ) with hydrochloric acid (HCl); And
After the reaction by the addition of a primary basicity adjusting agent is aluminum sulfate (Aluminium sulfate) to said poly aluminum chloride, secondary basicity adjusting agent is to put the reaction the number of strong acid difference chlorate, aluminum (Al ₂ O ₃₎ content of 10.0 to oxidation 16.0% by weight, basicity of 5 to 25%, residual chlorine is 0.02 to 2mg / ℓ, hypochlorous acid polyaluminum sulfate represented by [Formula 1] ((Hypochlorous PolyAluminium Chloro Sulfate, HCPACS) flocculant preparation agent Stage 2;
[Formula 1] Al ₂ (OH) _a Cl _b (SO4) _c (OCl) _d
It comprises,
In [Formula 1] a + b + c + d = 6, the range is 0.3≤a≤1.5, 4.2≤b≤5.6, characterized in that 0.1≤c≤0.3, 0.000002≤d≤0.0002), A method for preparing a low-base coagulant using strong acidic hypochlorous acid water.
delete The method according to claim 1,
The primary basicity adjusting agent in the second step is 1 at 100 to 130 ° C. while stirring 2 mol of solid aluminum hydroxide (purity of 99.5% or more, 3 mol of sulfuric acid (H ₂ SO ₄ 98%)) at 58 to 120 rpm. A method for preparing a low-base coagulant using strong acidic hypochlorous acid water, characterized in that the aluminum oxide content produced by reacting for 3 hours is 8.0% by weight and 0% basicity of aluminum sulfate.
The method according to claim 1,
The polyaluminum chloride in the first step is 3 to 6 at 150 to 160 ° C. while stirring 2 mol of solid aluminum hydroxide (purity of 99.5% or more, dry phase) and 3.6 mol of hydrochloric acid (HCl 30 to 35%) at 58 to 120 rpm. After producing a PAC having an Al ₂ O ₃ content of 18 to 20% by weight by reacting with time, Al ₂ O ₃ content is 16.10% by weight, and a basicity of 35.0 to 45.0% by adding dilution water to the PAC. , A method of preparing a low-base coagulant using strong acidic hypochlorous acid water.
The method according to claim 1,
The secondary basicity regulator of the second step is prepared by stirring and reacting hydrochloric acid (HCl 35%) in a mixed solution of sodium hypochlorite and water, or an electrolytic cell composed of an insoluble electrode in a solution of water and hydrochloric acid (HCl 35%). Method for producing a low-base coagulant using strong acidic hypochlorous acid water, characterized in that the residual chlorine amount is 0.5 to 150 mg / ℓ concentration by applying a direct current voltage (1.6 V) and a current (1 A).
The method according to claim 1,
In the first step, the Al ₂ O ₃ content generated by reacting aluminum hydroxide (Al (OH) ₃ ) and hydrochloric acid (HCl) in a high temperature and high pressure reactor at 150 to 160 ° C. for 3 to 6 hours is 15 to 20 weight. %, Is a step of preparing polyaluminum chloride having a basicity of 35.0 to 45.0%,
In the second step, after reacting for 0.1 to 1 hour at a temperature condition of 60 to 100 ° C while stirring by adding aluminum sulfate having a basicity of 0%, which is the primary basicity adjusting agent, the basicity of the secondary basicity adjusting agent is 0%. Strong acidic hypochlorous acid was added to react for 0.1 to 1 hour at a temperature condition of 60 to 100 ℃, Al ₂ O ₃ content of 10.0 to 16.0% by weight, basicity of 5 to 25%, residual chlorine of 0.02 to 2mg / ℓ A method for producing a low-base coagulant using strong acidic hypochlorous acid water, which is characterized in that it is a step of producing polyaluminum hypochlorite.
A method for treating water or sewage and wastewater using a low-base coagulant using strong acidic hypochlorous acid water according to any one of claims 1 to 3 to 6.

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