A composite salt inhibitor for hazardous waste incineration quenching tower, preparation method and application thereof

Abstract

The invention discloses a composite salt blocking agent for a hazardous waste incineration quenching tower, a preparation method and an application thereof, which belongs to hazardous waste incineration treatment and is prepared from the following components: 50-90wt% of polyaminopolyether methylenephosphonic acid; 3-20wt% of oxalic acid; 3-20wt% of ammonium polyphosphate; and 0.01-1wt% of sodium dodecylbenzene sulfonate; wherein the oxalic acid is industrial oxalic acid produced by oxidation. The invention has an ideal salt blocking effect.

Description

Technical Field

[0001] The invention relates to hazardous waste incineration treatment, and in particular to a composite salt inhibitor for a hazardous waste incineration quenching tower, and a preparation method and application thereof. Background Art

[0002] The high-temperature exhaust gas generated by the hazardous waste incineration treatment device needs to be cooled quickly before entering the flue gas scrubber to remove the acidic gas and other harmful components in the exhaust gas. This rapid cooling process is usually completed in the quenching tower. For the purpose of green environmental protection, the current hazardous waste incineration treatment device generally uses the salt-containing wastewater from the flue gas scrubber to be sprayed back into the quenching tower to achieve the rapid cooling of the high-temperature exhaust gas.

[0003] However, the brine back-spray quenching tower process faces a huge problem during operation: when the salty wastewater is back-sprayed into the quenching tower, the waste salt is precipitated not only at the bottom of the quenching tower, but also on the inner wall of the quenching tower. Once the waste salt is precipitated on the wall of the quenching tower, a dense salt layer with a thickness of tens of centimeters to several meters is formed on the inner wall of the quenching tower in a short period of time, which makes the operating conditions of the quenching tower deteriorate sharply and causes the device to shut down. In order to put the quenching tower back into operation, it is necessary to enter the quenching tower to manually remove the accumulated salt. On the one hand, the formation of salt accumulation seriously affects the normal operation of the device, and on the other hand, the operating environment for cleaning the salt accumulation is poor, which poses a huge health impact and safety hazard to the operators.

[0004] In the prior art, in order to solve the problem of the deterioration of the operating conditions of the quench tower caused by the accumulation of dense salt layers on the inner wall of the quench tower, a pipe connected to the brine return spray pipe is set during the brine back-spray, and a salt inhibitor is introduced through the newly set pipe. The back-sprayed brine is mixed with the salt inhibitor before spraying, thereby reducing the accumulation of dense salt layers on the inner wall of the quench tower. Among the salt inhibitors currently used for quench towers, polyaminopolyethermethylenephosphonic acid (PAPEMP) has been used in the quench tower of the hazardous waste incineration treatment system, and oxalic acid, citric acid, polyacrylic acid, and phytic acid are also used as salt inhibitors.

[0005] However, the existing polyaminopolyether-based methylenephosphonic acid and oxalic acid, citric acid, polyacrylic acid, and phytic acid each have their own shortcomings. Among them, polyaminopolyether-based methylenephosphonic acid mainly has a good salt-blocking effect on calcium, but a poor effect on other salt ions, and the price of polyaminopolyether-based methylenephosphonic acid is relatively high. Although oxalic acid, citric acid, polyacrylic acid, and phytic acid have salt-blocking effects on calcium and magnesium and have relatively low costs, their salt-blocking effects are poor. Therefore, there is room for improvement in the salt-blocking effect of polyaminopolyether-based methylenephosphonic acid and oxalic acid, citric acid, polyacrylic acid, and phytic acid, which has become a problem that the industry urgently needs to solve.

[0006] The above background technology is for facilitating the understanding of the present invention and is not the known technology disclosed to the general public before the application of the present invention. Summary of the invention

[0007] In view of the above-mentioned defects, the present invention provides a method for improving at least one of the problems mentioned in the background technology.

[0008] The technical solution is: a composite salt inhibitor for a hazardous waste incineration quenching tower, made of the following ingredients:

[0009] Polyaminopolyether methylenephosphonic acid 50~90wt%;

[0010] Oxalic acid 3~20 wt%;

[0011] Ammonium polyphosphate 3-20 wt%; and

[0012] Sodium dodecylbenzene sulfonate 0.01~1 wt%;

[0013] Among them, oxalic acid is industrial oxalic acid produced by oxidation process.

[0014] Furthermore, the polyaminopolyether-based methylenephosphonic acid comprises 70-80 wt % of oxalic acid, 9-15 wt % of ammonium polyphosphate, and 0.05-0.2 wt % of sodium dodecylbenzene sulfonate.

[0015] Furthermore, the degree of polymerization of the ammonium polyphosphate is 2 to 20.

[0016] Furthermore, the composite salt inhibitor for the hazardous waste incineration quenching tower is prepared by the following steps:

[0017] S1, stirring oxalic acid and ammonium polyphosphate evenly, then adding sodium dodecylbenzene sulfonate, stirring evenly to form a mixture;

[0018] S2, add polyamino polyether methylene phosphonic acid into the reaction kettle, then add the mixture of S1 into the reaction kettle, stir evenly, and obtain a composite salt inhibitor.

[0019] The invention also provides a method for preparing a composite salt inhibitor for a hazardous waste incineration quenching tower.

[0020] The technical solution is: a method for preparing a composite salt inhibitor for a hazardous waste incineration quenching tower, comprising the following steps:

[0021] S1, stirring oxalic acid and ammonium polyphosphate evenly, then adding sodium dodecylbenzene sulfonate, stirring evenly to form a mixture;

[0022] S2, add polyamino polyether methylene phosphonic acid into the reaction kettle, then add the mixture of S1 into the reaction kettle, stir evenly, and obtain a composite salt inhibitor;

[0023] Among them, polyamino polyether methylene phosphonic acid 50~90wt%;

[0024] Oxalic acid 3~20 wt%;

[0025] Ammonium polyphosphate 3-20 wt%; and

[0026] Sodium dodecylbenzene sulfonate 0.01~1 wt%;

[0027] Oxalic acid is industrial oxalic acid produced by oxidation process.

[0028] Furthermore, the polyaminopolyether-based methylenephosphonic acid comprises 70-80 wt % of oxalic acid, 9-15 wt % of ammonium polyphosphate, and 0.05-0.2 wt % of sodium dodecylbenzene sulfonate.

[0029] Furthermore, the degree of polymerization of the ammonium polyphosphate is 2 to 20.

[0030] The invention also provides an application of the composite salt inhibitor.

[0031] The technical solution is: the above-mentioned composite salt inhibitor for hazardous waste incineration quenching tower is applied to the hazardous waste incineration quenching tower, and the dosage of the composite salt inhibitor for hazardous waste incineration quenching tower is 1-20 mg per 1L of back-sprayed brine.

[0032] Compared with the prior art, the present invention has the following beneficial effects:

[0033] The inventor team of the present invention unexpectedly discovered in production practice that when polyaminopolyether methylenephosphonic acid, oxidized oxalic acid, ammonium polyphosphate and sodium dodecylbenzene sulfonate are combined together, a synergistic effect is obtained, achieving an amazing salt-blocking effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 It is a schematic diagram of the front view of the online detection device for the salt blocking effect of the hazardous waste incineration quenching tower of the present invention;

[0035] Figure 2 It is a schematic side view of an online detection device for the salt blocking effect of a hazardous waste incineration quenching tower of the present invention;

[0036] In the figure: 1. detection tower body, 2. gas inlet, 3. gas outlet, 4. salt water injection device, 5. injection inlet pipe, 6. salt inhibitor branch pipe, 7. weighing bracket, 8. weighing structure, 9. platform. DETAILED DESCRIPTION

[0037] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0038] Those skilled in the art will appreciate that the following examples are only used to illustrate the present application and should not be considered as limiting the scope of the present application. If specific conditions are not specified in the examples, they are carried out according to normal conditions or conditions recommended by the manufacturer. If the manufacturer is not specified for the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0039] In these examples, parts and percentages are by mass unless otherwise indicated.

[0040] "Parts by mass" refers to the basic unit of measurement for expressing the mass ratio of multiple components. 1 part can represent any unit mass, such as 1g or 2.689g. If we say that the mass of component A is a parts and the mass of component B is b parts, it means the ratio of the mass of component A to the mass of component B is a:b. Alternatively, it means that the mass of component A is aK and the mass of component B is bK (K is an arbitrary number, indicating a multiple factor). It should not be misunderstood that, unlike the mass parts, the sum of the mass of all components is not limited to 100 parts.

[0041] "And / or" is used to indicate that one or both of the stated situations may occur, for example, A and / or B includes (A and B) and (A or B).

[0042] In these examples, the molecular weight of the polyacrylic acid is 280 and the degree of polymerization of the ammonium polyphosphate is 15.

[0043] Example 1

[0044] S1, stir 14.8kg oxalic acid (oxidation process industrial oxalic acid, purchased from the market) and 15.1kg ammonium polyphosphate evenly, then add 0.1kg sodium dodecylbenzene sulfonate, stir evenly to form a mixture, and set the mixture aside for later use.

[0045] S2, add 70kg of polyamino polyether methylene phosphonic acid into the reactor, then add the mixture stirred evenly in S1 into the reactor, stir evenly to obtain a composite salt inhibitor.

[0046] Example 2

[0047] S1, stir 12.9kg oxalic acid (oxidation process industrial oxalic acid, purchased from the market) and 12.05kg ammonium polyphosphate evenly, then add 0.05kg sodium dodecylbenzene sulfonate, stir evenly to form a mixture, and set the mixture aside for later use.

[0048] S2, add 75kg of polyamino polyether methylene phosphonic acid into the reactor, then add the mixture stirred evenly in S1 into the reactor, stir evenly to obtain a composite salt inhibitor.

[0049] Example 3

[0050] S1, stir 9.3kg oxalic acid (oxidation process industrial oxalic acid, purchased from the market) and 10.5kg ammonium polyphosphate evenly, then add 0.2kg sodium dodecylbenzene sulfonate, stir evenly to form a mixture, and set the mixture aside for later use.

[0051] S2, add 80kg of polyamino polyether methylene phosphonic acid into the reactor, then add the mixture stirred evenly in S1 into the reactor, stir evenly to obtain a composite salt inhibitor.

[0052] Comparative Example 1

[0053] 100 kg of polyamino polyether methylene phosphonic acid was taken as a salt inhibitor.

[0054] Comparative Example 2

[0055] Take 100kg of oxalic acid (oxidation process industrial oxalic acid, purchased from the market) as a salt inhibitor.

[0056] Comparative Example 3

[0057] Take 100 kg of oxalic acid (industrial oxalic acid produced by the sodium formate method, purchased from the market) as a salt inhibitor.

[0058] Comparative Example 4

[0059] S1, stir 12.9kg oxalic acid (industrial oxalic acid from the sodium formate method, purchased from the market) and 12.05kg ammonium polyphosphate evenly, then add 0.05kg sodium dodecylbenzene sulfonate, stir evenly to form a mixture, and set the mixture aside for later use.

[0060] S2, add 75kg of polyamino polyether methylene phosphonic acid into the reactor, then add the mixture stirred evenly in S1 into the reactor, stir evenly to obtain a composite salt inhibitor.

[0061] Comparative Example 5

[0062] S1, 12.9 kg of polyacrylic acid and 12.05 kg of ammonium polyphosphate are stirred evenly, and then 0.05 kg of sodium dodecylbenzene sulfonate is added and stirred evenly to form a mixture, and the mixture is set aside for later use.

[0063] S2, add 75kg of polyamino polyether methylene phosphonic acid into the reactor, then add the mixture stirred evenly in S1 into the reactor, stir evenly to obtain a composite salt inhibitor.

[0064] Comparative Example 6

[0065] S1, 12.9 kg citric acid and 12.05 kg ammonium polyphosphate are stirred evenly, and then 0.05 kg sodium dodecylbenzene sulfonate is added and stirred evenly to form a mixture, and the mixture is set aside for later use.

[0066] S2, add 75kg of polyamino polyether methylene phosphonic acid into the reactor, then add the mixture stirred evenly in S1 into the reactor, stir evenly to obtain a composite salt inhibitor.

[0067] Comparative Example 7

[0068] S1, add 24.95kg of oxalic acid (oxidation process industrial oxalic acid, purchased from the market) and 0.05kg of sodium dodecylbenzene sulfonate, stir evenly to form a mixture, and set the mixture aside for later use.

[0069] S2, add 75kg of polyamino polyether methylene phosphonic acid into the reactor, then add the mixture stirred evenly in S1 into the reactor, stir evenly to obtain a composite salt inhibitor.

[0070] Comparative Example 8

[0071] S1, stir 12.9 kg of oxalic acid (oxidation process industrial oxalic acid, purchased from the market) and 12.05 kg of ammonium polyphosphate to form a mixture, and set the mixture aside for later use.

[0072] S2, add 75.05kg of polyamino polyether methylene phosphonic acid into the reactor, then add the mixture stirred evenly in S1 into the reactor, stir evenly to obtain a composite salt inhibitor.

[0073] Comparative Example 9

[0074] S1, stir 12.9 kg oxalic acid (oxidation process industrial oxalic acid, purchased from the market) and 12.05 kg ammonium polyphosphate evenly, then add 0.05 kg dodecyl dimethyl benzyl ammonium chloride, stir evenly to form a mixture, and set the mixture aside for later use.

[0075] S2, add 75kg of polyamino polyether methylene phosphonic acid into the reactor, then add the mixture stirred evenly in S1 into the reactor, stir evenly to obtain a composite salt inhibitor.

[0076] Comparative Example 10

[0077] S1, stir 12.9 kg oxalic acid (oxidation process industrial oxalic acid, purchased from the market) and 12.05 kg ammonium polyphosphate evenly, then add 0.05 kg sodium dioctyl sulfosuccinate, stir evenly to form a mixture, and set the mixture aside for later use.

[0078] S2, add 75kg of polyamino polyether methylene phosphonic acid into the reactor, then add the mixture stirred evenly in S1 into the reactor, stir evenly to obtain a composite salt inhibitor.

[0079] In order to obtain the salt blocking effect of the salt blocking agent of Examples 1 to 3 and Comparative Examples 1 to 10 in the quench tower of the hazardous waste incineration treatment device, we designed a salt blocking effect detection device dedicated to online detection of the quench tower of the hazardous waste incineration treatment device, please refer to Figure 1-Figure 2 , Figure 1 This is a schematic diagram of the front view of the online detection device for the salt blocking effect of the hazardous waste incineration quenching tower of the present invention, Figure 2 It is a schematic side view of an online detection device for the salt blocking effect of a hazardous waste incineration quenching tower according to the present invention.

[0080] An online detection device for the salt-blocking effect of a hazardous waste incineration quenching tower is a scaled-down version of the quenching tower, comprising a detection tower body 1, the detection tower body 1 being respectively connected to a gas inlet 2 and a gas outlet 3, a brine injection device 4 being arranged in the detection tower body 1 (the brine injection device passes through the tower wall of the detection tower body 1), the brine injection device 4 being connected to an injection inlet pipe 5, and a salt-blocking agent branch pipe 6 being connected to the injection inlet pipe 5.

[0081] Different from the quenching tower, the online detection device for the salt blocking effect of the hazardous waste incineration quenching tower also includes a weighing structure 8, which is installed on a hollow platform 9. The detection tower body 1 is provided with a weighing bracket 7, which is placed on the weighing structure 8, and the detection tower body 1 passes through the platform 9.

[0082] During the performance test, the pipeline of the gas inlet 2 is connected to the air inlet pipeline of the quenching tower, the gas pipeline of the gas outlet 3 is connected to the air outlet pipeline of the quenching tower, and the injection inlet pipe 5 is connected to the injection inlet pipe of the quenching tower. The connection position is before the brine is mixed with the salt inhibitor of the quenching tower.

[0083] By setting up an online detection device for the salt-blocking effect of the hazardous waste incineration quenching tower and running it in parallel with the quenching tower, the effect of the salt-blocking agent can be detected through changes in weight. At the same time, it does not affect the quenching tower. When it is turned on, it also reduces the burden on the quenching tower.

[0084] In the present invention, the volume of the detection tower body 1 is 1m 3 .

[0085] The salt inhibitors of Examples 1 to 3 and Comparative Examples 1 to 10 were mixed with the brine injected into the pipe 5 through the salt inhibitor branch pipe 6, and the salt blocking effect test was performed on each test. The time from the start to the end of each test was the same, which was 168 hours. In each test, except for the different salt inhibitors, the other conditions were as similar as possible to eliminate the test errors. The results are shown in Table 1.

[0086] Table 1 Salt blocking effect

[0087]

[0088] Remark:

[0089] 1. When the quenching tower operates normally, the salt content entering the quenching tower is about 15%, of which the sulfate content is about 9%, the chloride content is about 4%, the fluoride content is about 0.5%, and the bromide content is about 0.2%.

[0090] 2. The salt inhibitor content corresponding to each 1L of back-sprayed brine is 2mg.

[0091] 3. The weight change is the weight increase after the online detection device of the salt barrier effect of the hazardous waste incineration quenching tower has been run once (the online detection device of the salt barrier effect of the hazardous waste incineration quenching tower has been cleaned before each operation to ensure that the initial value is the same).

[0092] From the results in Table 1, we can see that:

[0093] It can be seen from Examples 1 to 3 that, under the same formula composition, as the content of polyaminopolyether methylenephosphonic acid increases, the amount of dense salt layer remaining in the online detection device for the salt blocking effect of the hazardous waste incineration quenching tower is smaller, and the salt blocking effect is better.

[0094] It can be seen from Comparative Examples 1 to 3 that the effect of polyaminopolyethermethylenephosphonic acid is much better than that of oxalic acid.

[0095] From Comparative Examples 2 and 3, it can be seen that the salt blocking effects of the oxidation method oxalic acid and the sodium formate method as salt blocking agents are basically the same.

[0096] From Example 2 and Comparative Examples 4 to 6, it can be seen that after sodium formate oxalic acid, polyacrylic acid and citric acid replace oxidative oxalic acid, the salt-blocking effect decreases sharply, but the salt-blocking effect of the formula formed by sodium formate oxalic acid, polyacrylic acid and citric acid is not much different and is basically equivalent.

[0097] It can be seen from Example 2 and Comparative Example 7 that after the addition of ammonium polyphosphate, a synergistic effect is formed with the formulation system, and the salt blocking effect is greatly improved.

[0098] It can be seen from Example 2 and Comparative Example 8 that after the addition of sodium dodecylbenzene sulfonate, a synergistic effect is formed with the formulation system, and the salt blocking effect is greatly improved.

[0099] It can be seen from Example 2 and Comparative Examples 8 to 10 that the addition of dodecyl dimethyl benzyl ammonium chloride not only did not improve the salt blocking effect, but worsened the salt blocking effect. Although the addition of dioctyl sodium sulfosuccinate also improved the salt blocking effect, the improvement was small.

[0100] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A composite salt inhibitor for a hazardous waste incineration quenching tower, characterized in that: Made with the following ingredients: Polyaminopolyether methylenephosphonic acid 50~90wt%; Oxalic acid 3~20 wt%; Ammonium polyphosphate 3-20 wt%; and Sodium dodecylbenzene sulfonate 0.01~1 wt%; Among them, oxalic acid is industrial oxalic acid produced by oxidation process.

2. The composite salt inhibitor for hazardous waste incineration quenching tower according to claim 1, characterized in that: The polyaminopolyether-based methylenephosphonic acid comprises 70-80 wt %, oxalic acid comprises 9-15 wt %, ammonium polyphosphate comprises 10-16 wt % and sodium dodecylbenzene sulfonate comprises 0.05-0.2 wt %.

3. The composite salt inhibitor for hazardous waste incineration quenching tower according to claim 1, characterized in that: The degree of polymerization of the ammonium polyphosphate is 2 to 20.

4. The composite salt inhibitor for hazardous waste incineration quenching tower according to any one of claims 1 to 3, characterized in that: The composite salt inhibitor for hazardous waste incineration quenching tower is prepared by the following steps: S1, stirring oxalic acid and ammonium polyphosphate evenly, then adding sodium dodecylbenzene sulfonate, stirring evenly to form a mixture; S2, add polyamino polyether methylene phosphonic acid into the reaction kettle, then add the mixture of S1 into the reaction kettle, stir evenly, and obtain a composite salt inhibitor.

5. A method for preparing a composite salt inhibitor for a hazardous waste incineration quenching tower, characterized in that: The following steps are involved: S1, stirring oxalic acid and ammonium polyphosphate evenly, then adding sodium dodecylbenzene sulfonate, stirring evenly to form a mixture; S2, add polyamino polyether methylene phosphonic acid into the reaction kettle, then add the mixture of S1 into the reaction kettle, stir evenly, and obtain a composite salt inhibitor; Among them, polyamino polyether methylene phosphonic acid 50~90wt%; Oxalic acid 3~20 wt%; Ammonium polyphosphate 3-20 wt%; and Sodium dodecylbenzene sulfonate 0.01~1 wt%; Oxalic acid is industrial oxalic acid produced by oxidation process.

6. The method for preparing the composite salt inhibitor for hazardous waste incineration quenching tower according to claim 5, characterized in that: The polyaminopolyether-based methylenephosphonic acid comprises 70-80 wt % of the polyaminopolyether-based methylenephosphonic acid, 9-15 wt % of the oxalic acid, 10-16 wt % of the ammonium polyphosphate, and 0.05-0.2 wt % of the sodium dodecylbenzene sulfonate.

7. The method for preparing a composite salt inhibitor for a hazardous waste incineration quenching tower according to claim 5, characterized in that: The degree of polymerization of the ammonium polyphosphate is 2 to 20.

8. Use of the composite salt inhibitor for hazardous waste incineration quenching tower according to any one of claims 1 to 4 in a hazardous waste incineration quenching tower, characterized in that: The dosage of the composite salt inhibitor for the hazardous waste incineration quenching tower is 1-20 mg per 1L of back-sprayed brine.

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