Two-component foam inhibitor, preparation method thereof and method for reducing foaming in humic acid urea production process

Abstract

The invention relates to a two-component foam inhibitor, a preparation method thereof and a method for reducing foaming in the production process of humic acid urea. A foaming control agent in the two-component foam inhibitor reduces the pH value of a humate solution and reduces the generation amount of ammonia gas in the urea melt on one hand, and on the other hand, the problems that the humate solution is condensed and the humate solution is difficult to add into the urea melt due to reduction of the pH value can be avoided; the suspension adsorbent in the two-component foam inhibitor can adsorb free ammonia in the urea melt and ammonia generated after the humate solution is added. In conclusion, the double-component foam inhibitor provided by the invention can effectively reduce foaming reaction in the production process of humic acid urea, avoid pulverization of humic acid urea particles and improve the production efficiency.

Description

Technical Field

[0001] The invention belongs to the technical field of value-added urea preparation, and specifically relates to a two-component foam suppressant and a preparation method thereof, and a method for reducing foaming in a humic acid urea production process. Background Art

[0002] Humic acid urea has the effects of inhibiting soil urease activity, slowing down urea conversion and reducing ammonia volatilization losses, and has been widely welcomed by urea production companies and farmers in recent years. At present, the annual output of humic acid urea in China is about 1 million tons, accounting for 1 / 3 of China's value-added urea output.

[0003] However, humic acid needs to be added to urea in the form of humate solution. Since humate (potassium humate, sodium humate, etc.) is alkaline, a large amount of ammonia will be instantly generated after being added to the urea melt, and a large amount of foaming will be generated in the urea melt, leading to the following problems: 1) The humic acid urea particles produced contain bubbles, the particle strength is low, and they are easy to break during storage and transportation; 2) Humic acid urea produces a lot of dust, which reduces production efficiency and increases additional costs for recycling; 3) It affects the enthusiasm of urea companies to produce humic acid urea; 4) The product has a lot of dust, and the enthusiasm of farmers to apply it is also affected. Therefore, solving the foaming problem in the production process of humic acid urea is an important part of promoting the healthy development of the humic acid urea industry.

[0004] Humate solution has good fluidity only under alkaline conditions and can be accurately added to urea melt by a metering pump. Therefore, adjusting the pH of humate solution is an effective way to reduce foaming of urea melt. However, when the pH of humate solution is reduced to a moderately acidic state, the humate solution will condense and produce precipitation, making it difficult to add the humate solution to the urea melt. Summary of the invention

[0005] The purpose of the present invention is to provide a two-component foam suppressor and a preparation method thereof and a method for reducing foaming in a humic acid urea production process. The two-component foam suppressor provided by the present invention can prevent humate solution from condensing under non-alkaline conditions and effectively reduce foaming in a humic acid urea production process.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] The present invention provides a two-component foam suppressant, comprising a foam control agent and a suspension adsorbent;

[0008] The raw materials of the foam control agent include lactic acid, acetic acid and metal oxide;

[0009] The raw materials of the suspended adsorbent include vegetable oil, polysaccharide, organic acid and adsorbent;

[0010] The polymerization degree of the polysaccharide is 3 to 10; and the organic acid does not include lactic acid and acetic acid.

[0011] Preferably, the metal oxide includes one or more of zinc oxide, copper oxide, iron oxide, manganese oxide and calcium oxide;

[0012] The lactic acid is a lactic acid solution; the mass concentration of the lactic acid solution is 85%;

[0013] The acetic acid is an acetic acid solution; the mass concentration of the acetic acid solution is 80%.

[0014] Preferably, the mass ratio of the lactic acid to the acetic acid solution is 300-400:100-200;

[0015] The mass ratio of the lactic acid to the metal oxide is 300-400:120-160.

[0016] Preferably, the mass ratio of the vegetable oil to the polysaccharide is 500-600:200-300;

[0017] The mass ratio of the vegetable oil to the organic acid is 500-600:50-100;

[0018] The mass ratio of the total mass of the vegetable oil, polysaccharide and organic acid to the mass of the adsorbent is 1000:30-100.

[0019] Preferably, the vegetable oil includes one or more of palm oil, corn oil and cottonseed oil;

[0020] The polysaccharide includes one or more of maltooligosaccharide, isomaltooligosaccharide, fructooligosaccharide, galacto-oligosaccharide and xylo-oligosaccharide;

[0021] The organic acid is an organic carboxylic acid;

[0022] The adsorbent includes one or more of silica gel powder and zeolite powder.

[0023] The present invention also provides a method for preparing the two-component antifoaming agent described in the above scheme, comprising the following steps:

[0024] (1) heating and mixing lactic acid, acetic acid, a metal oxide and water to perform a double decomposition reaction to obtain a foam control agent;

[0025] (2) heating and mixing the vegetable oil, polysaccharide and organic acid to obtain a viscous liquid, and then mixing the viscous liquid and an adsorbent to obtain a suspended adsorbent;

[0026] There is no time sequence requirement for step (1) and step (2).

[0027] The present invention also provides a method for reducing foaming in a humic acid urea production process, comprising a first evaporation section and a second evaporation section, and between the first evaporation section and the second evaporation section, comprising the following steps:

[0028] (1) mixing a suspended adsorbent and a molten solution of urea to obtain a urea premix solution;

[0029] (2) heating and mixing the humate solution and the foam control agent to obtain a humate premix solution;

[0030] (3) Mixing the urea premixed liquid and the humate premixed liquid.

[0031] Preferably, the volume mass ratio of the suspended adsorbent to urea is (2-5) L:1t;

[0032] The volume ratio of the foaming control agent to the humate solution is 50-200:500;

[0033] The mass concentration of the humate solution is 10-18%.

[0034] Preferably, the volume mass ratio of the humate premix to urea is (8-20) L:1t.

[0035] Preferably, the temperature of the heating and mixing is 60-80°C.

[0036] The present invention provides a two-component foam suppressor. On the one hand, the foam control agent in the two-component foam suppressor of the present invention reduces the pH value of the humate solution and reduces the amount of ammonia generated in the urea melt. On the other hand, lactic acid and acetic acid form complexes with metal ions in metal oxides, which can prevent humic acid from combining with metal ions to form precipitation in a short period of time, thereby avoiding the problem of condensation of the humate solution and difficulty in adding to the urea melt due to the reduction of the pH value; the suspended adsorbent in the two-component foam suppressor of the present invention can absorb free ammonia in the urea melt and ammonia generated after the humate solution is added. Therefore, the two-component foam suppressor provided by the present invention can effectively reduce the foaming reaction in the production process of humic acid urea, avoid the pulverization of humic acid urea particles, and improve production efficiency.

[0037] The present invention also provides a method for preparing the two-component foam suppressant of the above scheme. The preparation method provided by the present invention has simple steps, convenient operation, high feasibility, and has the prospect of large-scale industrial production.

[0038] The present invention also provides a method for reducing foaming in the production process of humic acid urea. The present invention adopts a two-component foam suppressor, utilizes its foam control agent and suspension adsorbent, mixes it with a humate solution and adds it to a urea melt, exerts force in two directions of early adsorption and late buffering, greatly reduces the generation of ammonia in the production process of humic acid urea, thereby eliminating bubbles, improving urea granulation rate, increasing granule strength, reducing dust generation, and improving production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0040] Figure 1 A process flow chart of the method for reducing foaming in the production process of humic acid urea provided by the present invention;

[0041] Figure 2 This is a morphology diagram of the urea particles in Test Example 1 of the present invention. DETAILED DESCRIPTION

[0042] The present invention provides a two-component foam suppressant, comprising a foam control agent and a suspension adsorbent;

[0043] The raw materials of the foam control agent include lactic acid, acetic acid and metal oxide;

[0044] The raw materials of the suspended adsorbent include vegetable oil, polysaccharide, organic acid and adsorbent;

[0045] The polymerization degree of the polysaccharide is 3 to 10; and the organic acid does not include lactic acid and acetic acid.

[0046] The two-component foam suppressor provided by the present invention comprises a foam control agent; the raw materials of the foam control agent include lactic acid, acetic acid and metal oxides. In the present invention, the metal oxide preferably includes one or more of zinc oxide, copper oxide, iron oxide, manganese oxide and calcium oxide; the lactic acid is preferably a lactic acid solution; the mass concentration of the lactic acid solution is preferably 85%; the acetic acid is preferably an acetic acid solution; the mass concentration of the acetic acid solution is preferably 80%.

[0047] In the present invention, the mass ratio of the lactic acid to the acetic acid solution is preferably 300-400:100-200, more preferably 320-380:120-180, and further preferably 340-360:140-160.

[0048] In the present invention, the mass ratio of the lactic acid to the metal oxide is preferably 300-400:120-160, more preferably 320-380:130-150, and further preferably 340-360:140.

[0049] The two-component foam suppressor provided by the present invention includes a suspension adsorbent; the raw materials of the suspension adsorbent include vegetable oil, polysaccharide, organic acid and adsorbent; the organic acid does not include lactic acid and acetic acid. In the present invention, the vegetable oil preferably includes one or more of palm oil, corn oil and cottonseed oil; the polysaccharide preferably includes one or more of maltooligosaccharide, isomaltooligosaccharide, fructooligosaccharide, galacto-oligosaccharide and xylo-oligosaccharide; the polymerization degree of the polysaccharide is preferably 3-9, more preferably 4-8, and further preferably 5-7; the organic acid is preferably an organic carboxylic acid; the organic carboxylic acid preferably includes one or more of dicarboxylic acid and polycarboxylic acid; the dicarboxylic acid preferably includes one or more of oxalic acid, malic acid and succinic acid; the polycarboxylic acid is preferably citric acid; the adsorbent preferably includes one or more of silica gel powder and zeolite powder; the fineness of the adsorbent is preferably above 300 mesh, more preferably above 500 mesh, and further preferably 500-700 mesh.

[0050] In the present invention, the mass ratio of the vegetable oil to the polysaccharide is preferably 500-600:200-300, more preferably 520-580:220-280, and further preferably 540-560:240-260.

[0051] In the present invention, the mass ratio of the vegetable oil to the organic acid is preferably 500-600:50-100, more preferably 520-580:60-90, and further preferably 540-560:70-80.

[0052] In the present invention, the ratio of the total mass of the vegetable oil, polysaccharide and organic acid to the mass of the adsorbent is preferably 1000:30-100, more preferably 1000:50-90, and further preferably 1000:60-70.

[0053] The present invention also provides a method for preparing the two-component antifoaming agent described in the above scheme, comprising the following steps:

[0054] (1) heating and mixing lactic acid, acetic acid, a metal oxide and water to perform a double decomposition reaction to obtain a foam control agent;

[0055] (2) heating and mixing the vegetable oil, polysaccharide and organic acid to obtain a viscous liquid, and then mixing the viscous liquid and an adsorbent to obtain a suspended adsorbent;

[0056] There is no time sequence requirement for step (1) and step (2).

[0057] In the present invention, lactic acid, acetic acid, metal oxide and water are heated and mixed (referred to as the first heating and mixing) to perform a double decomposition reaction to obtain a foam control agent. In the present invention, the solid content of the foam control agent is preferably 100 to 200 g / L, more preferably 120 to 180 g / L, and further preferably 140 to 160 g / L.

[0058] In the present invention, the temperature of the first heating and mixing is preferably 60 to 80°C, more preferably 65 to 75°C, and further preferably 70°C.

[0059] In the present invention, the apparatus for the double decomposition reaction is preferably a reactor; the temperature of the double decomposition reaction is preferably 60-80°C, more preferably 65-75°C, further preferably 70°C, and the insulation time is preferably 15-30min, more preferably 20-25min; the double decomposition reaction is preferably carried out under stirring conditions.

[0060] The present invention heats and mixes vegetable oil, polysaccharide and organic acid (referred to as the second heating and mixing) to obtain a viscous liquid, and then mixes the viscous liquid and an adsorbent to obtain a suspended adsorbent. In the present invention, the second heating and mixing is preferably carried out under anhydrous conditions; the temperature of the second heating and mixing is preferably 100 to 120°C, more preferably 105 to 115°C, and further preferably 110°C, and the insulation time is preferably 30 to 60 minutes, more preferably 40 to 50 minutes; the second heating and mixing device is preferably a reactor.

[0061] The present invention also provides a method for reducing foaming in a humic acid urea production process, comprising a first evaporation section and a second evaporation section, and between the first evaporation section and the second evaporation section, comprising the following steps:

[0062] (1) mixing a suspended adsorbent and a molten solution of urea to obtain a urea premix solution;

[0063] (2) heating and mixing the humate solution and the foam control agent to obtain a humate premix solution;

[0064] (3) Mixing the urea premixed liquid and the humate premixed liquid.

[0065] The present invention mixes a suspended adsorbent and a molten solution of urea to obtain a urea premix. In the present invention, the volume mass ratio of the suspended adsorbent to urea is preferably (2-5) L:1t, more preferably (3-5) L:1t, and further preferably (3-4) L:1t; the suspended adsorbent is preferably weighed by a metering pump.

[0066] The present invention heats and mixes the humate solution and the foaming control agent (referred to as the third heating and mixing) to obtain a humate premix. In the present invention, the volume ratio of the foaming control agent to the humate solution is preferably 50 to 200:500, more preferably 80 to 180:500, and further preferably 120 to 150:500; the mass concentration of the humate solution is preferably 10% to 18%, more preferably 12% to 16%, and further preferably 14%.

[0067] In the present invention, the temperature of the third heating and mixing is preferably 60-80°C, more preferably 65-75°C, and further preferably 70°C; the heating and mixing device is preferably a buffer tank with a stirring and heating and heat preservation system.

[0068] After obtaining the urea premix and the humate premix, the present invention mixes the urea premix and the humate premix. In the present invention, the volume mass ratio of the humate premix to urea is preferably (8-20) L:1t, more preferably (10-17) L:1t, and further preferably (12-15) L:1t.

[0069] In the present invention, the humate premix is ​​preferably weighed by a metering pump.

[0070] Figure 1 The process flow chart of the method for reducing foaming in the humic acid urea production process provided by the present invention. The present invention is based on the process of preparing humic acid urea. Between the first evaporation section and the second evaporation section, a suspended adsorbent is weighed by a metering pump and mixed with a urea melt to obtain a urea premixed liquid. Then, a humate solution and a foaming control agent are weighed by a metering pump and heated and mixed in a buffer tank. Then, the obtained humate premixed liquid is weighed by a metering pump and mixed with a urea premixed liquid. After that, the humic acid urea is obtained through two-stage evaporation and high-tower granulation, thereby effectively reducing the foaming phenomenon in the humic acid urea production process.

[0071] In order to further illustrate the present invention, the scheme of the present invention is described in detail below in conjunction with the accompanying drawings and embodiments, but they should not be understood as limiting the protection scope of the present invention.

[0072] Example 1

[0073] The preparation of a two-component antifoam agent in this embodiment comprises the following steps:

[0074] (1) Preparation of foam control agent

[0075] Lactic acid with a mass concentration of 85%, acetic acid solution with a mass concentration of 80% and calcium oxide were added to a reactor at a mass ratio of 300:100:120, and then water was added to the reactor, heated to 60°C, and stirred for reaction for 30 minutes to obtain a foaming control agent with a concentration of 100 g / L.

[0076] (2) Preparation of suspended adsorbent

[0077] Vegetable oil, polysaccharide with a polymerization degree of 3 to 10 and organic acid are mixed in a mass ratio of 500:200:50, heated to 100°C in a reactor under anhydrous conditions, and kept warm for 60 minutes to obtain a viscous liquid. Then, an adsorbent with a fineness of more than 300 mesh is added to the viscous liquid in a mass ratio of adsorbent to viscous liquid of 30:1000, and stirred evenly to obtain a suspended adsorbent.

[0078] The vegetable oil is palm oil; the polysaccharide is maltooligosaccharide; the organic acid is oxalic acid; and the adsorbent is silica gel powder.

[0079] Example 2

[0080] The preparation of a two-component antifoam agent in this embodiment comprises the following steps:

[0081] (1) Preparation of foam control agent

[0082] Lactic acid with a mass concentration of 85%, acetic acid solution with a mass concentration of 80% and zinc oxide were added to a reactor at a mass ratio of 400:200:160, and then water was added to the reactor, heated to 80°C, and stirred for reaction for 15 minutes to obtain a foaming control agent with a concentration of 200 g / L.

[0083] (2) Preparation of suspended adsorbent

[0084] Vegetable oil, polysaccharide with a polymerization degree of 3 to 10 and organic acid are mixed in a mass ratio of 600:300:100, heated to 120°C in a reactor under anhydrous conditions, and kept warm for 30 minutes to obtain a viscous liquid. Then, an adsorbent with a fineness of more than 300 mesh is added to the viscous liquid in a mass ratio of adsorbent to viscous liquid of 100:1000, and stirred evenly to obtain a suspended adsorbent.

[0085] The vegetable oil is corn oil; the polysaccharide is isomaltooligosaccharide; the organic acid is citric acid; and the adsorbent is zeolite powder.

[0086] Example 3

[0087] The preparation of a two-component antifoam agent in this embodiment comprises the following steps:

[0088] (1) Preparation of foam control agent

[0089] Lactic acid with a mass concentration of 85%, acetic acid solution with a mass concentration of 80% and manganese oxide were added to a reactor at a mass ratio of 350:150:140, and then water was added to the reactor, heated to 70°C, and stirred for reaction for 20 minutes to obtain a foaming control agent with a concentration of 150 g / L.

[0090] (2) Preparation of suspended adsorbent

[0091] Vegetable oil, polysaccharide with a polymerization degree of 3 to 10 and organic acid are mixed in a mass ratio of 550:250:80, heated to 110°C in a reactor under anhydrous conditions, and kept warm for 50 minutes to obtain a viscous liquid. Then, an adsorbent with a fineness of more than 300 mesh is added to the viscous liquid in a mass ratio of adsorbent to viscous liquid of 60:1000, and stirred evenly to obtain a suspended adsorbent.

[0092] The vegetable oil is cottonseed oil; the polysaccharide is oligofructose; the organic acid is malic acid; and the adsorbent is silica gel powder.

[0093] Example 4

[0094] The preparation of a two-component antifoam agent in this embodiment comprises the following steps:

[0095] (1) Preparation of foam control agent

[0096] Lactic acid with a mass concentration of 85%, acetic acid solution with a mass concentration of 80%, copper oxide and iron oxide (the mass ratio of copper oxide to iron oxide is 1:1) are added to a reactor at a mass ratio of 300:200:130, and then water is added to the reactor, heated to 75°C, and stirred for reaction for 25 minutes to obtain a foaming control agent with a concentration of 180 g / L.

[0097] (2) Preparation of suspended adsorbent

[0098] Vegetable oil, polysaccharide with a polymerization degree of 3 to 10 and organic acid are mixed in a mass ratio of 580:230:65, heated to 105°C in a reactor under anhydrous conditions, and kept warm for 45 minutes to obtain a viscous liquid. Then, an adsorbent with a fineness of more than 300 mesh is added to the viscous liquid in a mass ratio of adsorbent to viscous liquid of 35:1000, and stirred evenly to obtain a suspended adsorbent.

[0099] The vegetable oil is cottonseed oil; the polysaccharide is galacto-oligosaccharide; the organic acid is succinic acid; and the adsorbent is zeolite powder.

[0100] Application Example 1

[0101] After the first evaporation stage and before the second evaporation stage:

[0102] (1) First, a suspended adsorbent is added to a urea melt at a rate of 2 L per ton of urea using a metering pump to adsorb free ammonia in the urea melt and ammonia generated by adding a humate solution to obtain a urea premix;

[0103] (2) A humate solution at 60° C. and 10% by mass concentration is added to a buffer tank with a stirring and heating insulation system (the temperature is maintained at 60° C.), and a 60° C. foaming control agent and a humate solution are added to the buffer tank at a volume ratio of 50:500 to obtain a humate premixed liquid, and then the humate premixed liquid is added to the urea premixed liquid (before the second evaporation stage and after the addition of the suspended adsorbent) through a metering pump. The amount of humate premixed liquid added to each ton of urea is 8 L.

[0104] Application Example 2

[0105] After the first evaporation stage and before the second evaporation stage:

[0106] (1) First, a suspended adsorbent is added to a urea melt at a rate of 5 L per ton of urea using a metering pump to adsorb free ammonia in the urea melt and ammonia generated by adding a humate solution to obtain a urea premix;

[0107] (2) A humate solution at 80° C. and a mass concentration of 18% is added to a buffer tank with a stirring and heating insulation system (the temperature is maintained at 80° C.), and a foaming control agent at 80° C. and a humate solution are added to the buffer tank at a volume ratio of 200:500 to obtain a humate premixed liquid, and then the humate premixed liquid is added to the urea premixed liquid (before the second evaporation stage and after the addition of the suspended adsorbent) through a metering pump. The amount of humate premixed liquid added to each ton of urea is 20 L.

[0108] Test Example 1

[0109] The two-component foam suppressor prepared in Example 1 was subjected to foaming reaction and humate coagulation tests, and the test method was as follows:

[0110] (1) Foaming reaction test

[0111] Three treatment groups were set up: T1 (ordinary urea melt), T2 (15L humate solution was added to each ton of urea melt) and T3 (4L suspended adsorbent was first added to each ton of urea melt, and then a humate premix obtained by mixing 15L humate solution and 1.5L foaming control agent was added). The urea melt was taken up with a dropper and quickly dropped into liquid paraffin to obtain urea granules, and the density of the urea granules was measured (it can characterize the amount of foaming in the urea granules, and the smaller the density, the more foaming).

[0112] Determination of urea granule density: The density of urea granules was determined by the drainage method. 6.5 g of T1, T2 and T3 urea granules were weighed and placed in a 50 mL measuring cylinder containing 30 mL of liquid paraffin, and the volume at this time was recorded. The volume of urea granules V1 (5.3 mL), V2 (6.0 mL) and V3 (5.1 mL) were calculated by the difference subtraction method. Finally, the density of urea granules was calculated. The results are shown in Table 1.

[0113] Wherein, urea granule density = urea granule mass / urea granule volume.

[0114] Table 1 Effect of humate and two-component defoamer on urea granule density

[0115] Group <![CDATA[Density (g / cm 3 )]]> T1 1.22 T2 1.08 T3 1.27

[0116] According to Table 1, compared with ordinary urea granules (T1), the density of humate urea granules (T2) is reduced by 11.5%, and the density of humate + two-component antifoaming agent urea granules (T3) is increased by 4.1% and 17.6% compared with T1 and T2, respectively, indicating that the two-component antifoaming agent provided by the present invention can solve the problem of foaming in the production process of humic acid urea.

[0117] The morphology of urea particles was observed, and the foaming of urea particles was observed. Figure 2 As shown. Figure 2 It can be seen that the particle size of T1 urea granules is uniform, and the surface of the urea granules is smooth and round; the particle size of T2 is low, the appearance is poor, the surface of the urea granules is not smooth, and the urea granules have pores; the particle size of T3 is high, the appearance is good, the surface of the urea granules is smooth, and no bubbles are generated.

[0118] (2) Humate coagulation test

[0119] Set up 3 treatments: H1, H2 and H3.

[0120] H1: Place a 60°C, 10% mass concentration humate solution (pH 10.09) into a beaker, place it on a 85-2A digital display constant temperature and speed magnetic stirrer (temperature maintained at 60°C), and stir for 5 minutes.

[0121] H2: Put a humate solution at 60°C and 10% mass concentration into a beaker, place it on the above-mentioned magnetic stirrer (the temperature is maintained at 60°C), then add a 60°C foaming control agent (the volume ratio of the foaming control agent to the humate solution is 50:500), stir for 5 minutes to obtain a humate premix solution, and measure the pH at this time to be 6.10;

[0122] H3: Put a humate solution at 60°C and 10% mass concentration into a beaker and place it on the above-mentioned magnetic stirrer (the temperature is maintained at 60°C), then slowly add potassium dihydrogen phosphate solution to the humate solution to adjust the pH value of the humate solution to 6.10, and stir the reaction for 5 minutes.

[0123] The viscosity of the H1, H2 and H3 treatments was measured using a digital viscometer (SNB-2; temperature 20°C, speed 60.0 RMP) to characterize the coagulation of the humate solution. The smaller the viscosity, the smaller the coagulation degree and the stronger the fluidity of the humate solution. The viscosity of the humate solution is shown in Table 2.

[0124] Table 2 Determination of viscosity of H1~H3 humate solutions

[0125] Group Viscosity (mPa·S) H1 1.31 H2 5.64 H3 342.6

[0126] According to Table 2, the viscosity of the humate solution with a mass concentration of 10% is 1.31 mPa·S, which has good fluidity. After adding the foaming control agent, the pH value of the humate solution decreases and the viscosity increases slightly. After adding potassium dihydrogen phosphate to the humate solution, the humate coagulates and precipitates seriously, and the viscosity of H3 is 60.7 times that of H2. This shows that the foaming control agent in the two-component foam suppressor provided by the present invention can increase the anti-coagulation ability and fluidity of the humate solution under moderately acidic conditions, and effectively solves the foaming problem in the production process of humic acid urea.

[0127] Test Example 2

[0128] The two-component foam suppressor of Example 2 was subjected to dust test, particle strength test and production efficiency calculation:

[0129] (1) Dust generation: 5-12 kg of dust is generated for every ton of ordinary humic acid urea produced; this method can reduce the dust generation per ton of humic acid urea to 1-3 kg.

[0130] (2) Particle strength: The particle strength of ordinary humic acid urea is 14-16N; this method can increase the particle strength of humic acid urea to 18-20N.

[0131] (3) Production efficiency: Humic acid urea manufacturers usually reduce production capacity to reduce urea dust generation. Taking the daily output of urea as 1,500 tons, the daily output needs to be reduced to about 1,200 tons when producing humic acid urea. This method can still maintain a daily output of 1,500 tons, greatly improving production efficiency.

[0132] It can be seen from the above embodiments that the two-component antifoaming agent provided by the present invention can prevent the humate solution from condensing under non-alkaline conditions, effectively reduce the foaming phenomenon in the humic acid urea production process, and the method provided by the present invention can eliminate bubbles, improve the urea granulation rate, increase the particle strength, reduce dust generation, and improve production efficiency.

[0133] Although the above embodiment describes the present invention in detail, it is only a part of the embodiments of the present invention, not all of the embodiments. Other embodiments can be obtained based on this embodiment without creativity, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A two-component foam suppressant, characterized in that: Includes foam control agents and suspended adsorbents; The raw materials of the foam control agent include lactic acid, acetic acid and metal oxide; The raw materials of the suspended adsorbent include vegetable oil, polysaccharide, organic acid and adsorbent; The polymerization degree of the polysaccharide is 3 to 10; and the organic acid does not include lactic acid and acetic acid.

2. The two-component foam suppressant according to claim 1, characterized in that: The metal oxide includes one or more of zinc oxide, copper oxide, iron oxide, manganese oxide and calcium oxide; The lactic acid is a lactic acid solution; the mass concentration of the lactic acid solution is 85%; The acetic acid is an acetic acid solution; the mass concentration of the acetic acid solution is 80%.

3. The two-component foam suppressor according to claim 1 or 2, characterized in that: The mass ratio of the lactic acid to the acetic acid solution is 300-400:100-200; The mass ratio of the lactic acid to the metal oxide is 300-400:120-160.

4. The two-component foam suppressant according to claim 1, characterized in that: The mass ratio of the vegetable oil to the polysaccharide is 500-600:200-300; The mass ratio of the vegetable oil to the organic acid is 500-600:50-100; The mass ratio of the total mass of the vegetable oil, polysaccharide and organic acid to the mass of the adsorbent is 1000:30-100.

5. The two-component foam suppressor according to claim 1 or 4, characterized in that: The vegetable oil includes one or more of palm oil, corn oil and cottonseed oil; The polysaccharide includes one or more of maltooligosaccharide, isomaltooligosaccharide, fructooligosaccharide, galacto-oligosaccharide and xylo-oligosaccharide; The organic acid is an organic carboxylic acid; The adsorbent includes one or more of silica gel powder and zeolite powder.

6. The method for preparing the two-component antifoam agent according to any one of claims 1 to 5, characterized in that: The following steps are involved: (1) heating and mixing lactic acid, acetic acid, a metal oxide and water to perform a double decomposition reaction to obtain a foam control agent; (2) heating and mixing the vegetable oil, polysaccharide and organic acid to obtain a viscous liquid, and then mixing the viscous liquid and an adsorbent to obtain a suspended adsorbent; There is no time sequence requirement for step (1) and step (2).

7. A method for reducing foaming in a humic acid urea production process, comprising a first evaporation section and a second evaporation section, characterized in that: Between the first evaporation section and the second evaporation section, the following steps are included: (1) mixing a suspended adsorbent and a molten solution of urea to obtain a urea premix solution; (2) heating and mixing the humate solution and the foam control agent to obtain a humate premix solution; (3) Mixing the urea premixed liquid and the humate premixed liquid.

8. The method according to claim 7, characterized in that The volume mass ratio of the suspended adsorbent to urea is (2-5) L:1 t; The volume ratio of the foaming control agent to the humate solution is 50-200:500; The mass concentration of the humate solution is 10-18%.

9. The method according to claim 7, characterized in that: The volume mass ratio of the humate premixed liquid to urea is (8-20) L:1 t.

10. The method according to claim 7, characterized in that The temperature of the heating and mixing is 60-80°C.

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