CN104845673A - A kind of scale inhibitor suitable for S Zorb gasoline desulfurization unit and its preparation method and application - Google Patents

Abstract

The invention relates to a scale inhibitor suitable for an S Zorb gasoline desulfurization device and a preparation method and application thereof. The scale inhibitor comprises or consists of the following components: antioxidant, polymerization inhibitor, metal deactivator, cleaning dispersant, filming agent and solvent. The scale inhibitor has the capabilities of resisting oxidation and inhibiting polymerization; before the scale inhibitor is applied to a raw material heat exchanger, the coking of equipment such as a heat exchange system, a pipeline, the heat exchanger and the like can be effectively inhibited, the safe and stable operation of the device is ensured, and the operation period of the device is prolonged.

Description

A kind of scale inhibitor suitable for S Zorb gasoline desulfurization unit and its preparation method and application

technical field

The invention relates to a scale inhibitor suitable for S Zorb gasoline desulfurization device and its preparation method and application.

Background technique

Gasoline adsorption desulfurization technology adopts the method of adsorption to make gasoline fully contact with the adsorbent with special structure, and adsorb mercaptans, disulfides, sulfides and thiophene sulfides in gasoline to the adsorbent, thereby reducing the sulfide in gasoline. sulfur content. Because this technology has the advantages of low equipment investment, high desulfurization rate, no hydrogen consumption and low price of adsorbent, it has become one of the key research and development topics of major oil companies at home and abroad.

The S Zorb process is a reactive adsorption desulfurization process developed by ConocoPhillips, which combines fluidized bed reactor and continuous regeneration technology, and has been successfully applied to the desulfurization of catalytic cracked gasoline and diesel oil. It is currently widely used in industrial applications. Adsorption desulfurization technology. Compared with traditional hydrodesulfurization technology, S-Zorb technology has small loss of octane number, small loss of anti-knock index (≤0.5), low hydrogen consumption, high liquid yield (yield of liquid components above C5>99.2 %), high desulfurization rate and low sulfur content (<10μg/g) in the product, which can fully meet the needs of the production of Euro IV and above standard gasoline, and highlight the technical advantages in the production of clean gasoline.

In the existing S Zorb adsorption desulfurization device, because the raw material catalytic gasoline contains colloid and other heavy components, in the process of heat exchange and temperature rise, scales are often generated in equipment such as heat exchangers and pipelines, and are deposited on the surface of the equipment. On the surface, the heat transfer coefficient of the equipment is reduced, the pressure drop is increased, and the energy consumption is increased. When the scale is serious, the equipment will be blocked and the device will be forced to stop working. In order to solve the scaling problem, the best way is to use scale inhibitors. By adding a very small amount of scale inhibitors to the production equipment, it can prevent scaling of equipment and pipelines, prolong the operation period of the equipment, and reduce energy consumption. The method is simple, easy to implement, low in cost, and convenient for practical application.

However, the main component of the existing scale inhibitor used in S Zorb adsorption desulfurization unit is trisodium phosphate, which contains metal ion sodium, which will lead to the deactivation of the adsorbent.

Contents of the invention

For overcoming the defective of prior art, the present invention provides a kind of antiscalant that is applicable to S Zorb gasoline desulfurization unit, and this antiscalant is oil-soluble liquid, and filling is convenient, does not affect other quality index of gasoline, and the present invention The antiscalant has no effect on the adsorbent in the S Zorb gasoline desulfurization unit.

The inventors of the present invention have continuously studied and analyzed the causes of fouling and found that the antiscalant should have anti-oxidation properties, and substances with anti-oxidation properties can provide an active atom to the peroxy group to generate a stable compound, so that Chain reaction termination; antiscalant should also have polymerization inhibitory ability, prevent olefin, diene from polymerizing and generate macromolecular hydrocarbons; The antiscalant should not contain metal ions to prevent accumulation in the reactor and affect the performance of the catalyst and product distribution.

Based on the above analysis, we have developed a multi-functional composite scale inhibitor with anti-oxidation, polymerization inhibition and film-forming capabilities. This scale inhibitor is suitable for S Zorb gasoline desulfurization unit and can effectively prevent fouling of raw gasoline heat exchangers. .

The present invention is realized by adopting the following technical solutions.

On the one hand, the present invention provides a kind of antiscalant that is applicable to S Zorb gasoline desulfurization unit, and this antiscalant comprises or is made up of following component: antioxidant, polymerization inhibitor, metal deactivator, cleaning dispersant, film-forming agents and solvents.

Preferably, in the above scale inhibitors, the antioxidant and polymerization inhibitors are formed by condensation of phenol and alcohol; more preferably, the antioxidant and polymerization inhibitors are formed by condensation of phenol and alcohol in the presence of a catalyst Reaction, after the reaction is completed, the product obtained through vacuum distillation.

Wherein, preferably, the phenol is selected from one or more of phenol and hydroquinone, preferably phenol;

Wherein, preferably, the alcohol is an alkyl alcohol, preferably a _C7-22 alkyl alcohol, more preferably a _C8-16 alkyl alcohol, most preferably secondary octanol;

Wherein, preferably, the molar ratio between the phenol and the alcohol is 1:2˜2:1, for example, 2:1, 2:2, 1:2 or 1:3, preferably 1:2.

Wherein, preferably, the catalyst is sulfuric acid or Al ₂ O ₃ , preferably Al ₂ O ₃ .

Wherein, preferably, the addition amount of the catalyst is 10-40% of the total mass of the reaction materials, preferably the addition amount of the catalyst is 20% of the total mass of the reaction materials.

Among them, preferably, the pressure of vacuum distillation is 1.0×10 ² -1.3×10 ^-1 Pa, preferably 1.0×10 ^-1 Pa.

Wherein, preferably, the temperature of vacuum distillation is 100°C-150°C, preferably 130°C.

Wherein, preferably, the time of vacuum distillation is 1h-15h, preferably 5h.

It should be noted that although the present invention provides methods for preparing antioxidants and polymerization inhibitors, antioxidants and polymerization inhibitors obtained from other sources, such as commercial purchases, are applicable to the present invention.

Preferably, in the scale inhibitor mentioned above, the antioxidant and polymerization inhibitor is secondary octylphenol.

Preferably, among the scale inhibitors mentioned above, the metal deactivator is selected from one or more of benzotriazole, benzotriazole and aminotriazole, preferably aminotriazole.

Preferably, in the above antiscalant, the detergent dispersant is polyisobutylene diimine.

Preferably, in the scale inhibitor mentioned above, the film forming agent is morpholine or oil-soluble imidazoline, preferably oil-soluble imidazoline.

Preferably, in the above scale inhibitor, the solvent is selected from 120#, 200#, 230# solvent naphtha, preferably 200 ^# solvent naphtha.

Preferably, in the scale inhibitor mentioned above, based on the total mass of the scale inhibitor, the mass percent content of the antioxidant and polymerization inhibitor is 10-40%, preferably 25%.

Preferably, in the scale inhibitor mentioned above, based on the total mass of the scale inhibitor, the mass percentage of the metal passivator is 2-8%, preferably 5%.

Preferably, in the scale inhibitor mentioned above, based on the total mass of the scale inhibitor, the mass percentage of the cleaning and dispersing agent is 10-30%, preferably 15%.

Preferably, in the scale inhibitor mentioned above, based on the total mass of the scale inhibitor, the mass percentage of the film-forming agent is 3-10%, preferably 4%.

Preferably, in the scale inhibitor mentioned above, based on the total mass of the scale inhibitor, the mass percentage of the solvent is 30-60%, preferably 51%.

In a specific embodiment, the formula of the antiscalant that the present invention is applicable to S Zorb gasoline desulfurization unit is as follows, and wherein percentage composition is mass percent composition:

Among them, the antioxidant and polymerization inhibitor are formed by condensation of phenol and sec-octanol, wherein the molar ratio of phenol and sec-octanol is 1:2. The antioxidant and polymerization inhibitor is formed by condensation of phenol and sec _- octanol under the action of catalyst _Al2O3 . Specifically, add secondary octanol, phenol, and catalyst _Al2O3 to the reactor, wherein the molar ratio of phenol to secondary octanol is 1: ₂ , and the catalyst _Al2O3 accounts for ₂₀ % of the total mass of the reaction material, and stir Raise the temperature to a reaction temperature of 150°C, maintain the reaction temperature, react for 5 hours, and distill under reduced pressure (pressure 1.0×10 ^-1 Pa) to obtain a product at a temperature of 130±5°C with a yield of 85%.

The reaction formula is as follows:

On the other hand, the present invention provides the preparation method of above-mentioned antiscalant, and this preparation method comprises the step of mixing antioxidant, polymerization inhibitor, metal deactivator, cleaning dispersant, film-forming agent and solvent in proportion; Preferably , using a homogenizer for mixing.

In another aspect, the present invention provides the application of the above-mentioned scale inhibitor or the scale inhibitor prepared by the above-mentioned preparation method for S Zorb gasoline desulfurization unit.

Preferably, in the above application, the antiscalant is applied before the raw catalytic gasoline heat exchanger, preferably mixed with raw catalytic gasoline components.

Preferably, in the above application, the added mass of antiscalant is 60-100ppm of the raw catalytic gasoline, preferably, within 30 days of starting operation, the added mass of antiscalant is 80-100ppm of raw catalytic gasoline, and then the antiscalant The added mass is 60-80ppm of raw catalytic gasoline.

In yet another aspect, the present invention provides a method for using the above-mentioned scale inhibitor or the scale inhibitor prepared by the above-mentioned preparation method, the method includes applying the scale inhibitor before the raw material catalytic gasoline heat exchanger, preferably with the raw material catalytic gasoline component mixed.

Preferably, the added quality of antiscalant is 60-100ppm of raw material catalytic gasoline, preferably, within one month of start-up, the added quality of antiscalant is 80-100ppm of raw material catalytic gasoline, after that the added quality of antiscalant is The raw material catalytic gasoline is 60-80ppm.

In the present invention, the antiscalant is injected before the raw catalytic gasoline heat exchanger.

In the present invention, the amount of antiscalant to be added is calculated according to the content of colloids and dienes in the raw material catalytic gasoline, and then the filling amount is adjusted according to the trend line of the temperature difference of the raw material catalytic gasoline heat exchanger.

The scale inhibitor suitable for S Zorb gasoline desulfurization device of the present invention has anti-oxidation properties, and the substance with anti-oxidation properties can provide an active atom to peroxygen to generate a stable compound, so that the chain reaction is terminated.

The scale inhibitor suitable for the S Zorb gasoline desulfurization device of the present invention has a polymerization inhibition function and can prevent olefins and diolefins from polymerizing to generate macromolecular hydrocarbons.

The scale inhibitor suitable for S Zorb gasoline desulfurization device of the present invention has the function of metal passivation, can react with metal ions in oil products to form stable complexes, and will not cause catalytic dehydrogenation condensation reaction and oxidation chain reaction.

The scale inhibitor suitable for the S Zorb gasoline desulfurization device of the present invention has the function of forming a film on the metal surface, and can form a protective film on the metal surface to prevent the metal from being corroded and accelerating scaling.

The scale inhibitor suitable for the S Zorb gasoline desulfurization device of the present invention has cleaning and dispersing properties, and once a small amount of scaling is generated, it can prevent them from aggregating to limit particle growth and deposition.

The scale inhibitor suitable for S Zorb gasoline desulfurization device of the present invention does not contain metal ions, so as to prevent aggregation in the reactor and affect the performance and product distribution of the catalyst.

The S Zorb special anti-coke and anti-scaling agent developed by the present invention can effectively prevent the raw material catalytic gasoline from fouling in the heat exchanger before it is applied to the raw material catalytic gasoline heat exchanger. When the dosage is 60ppm, the scale inhibition rate reaches 92%. Above, the recommended dosage for industrial application is 60-80ppm. The antiscalant is added at the initial stage of the start-up of the device, and the dosage is 80-100ppm within one month at the beginning of the operation, and the normal dosage is adopted afterwards. The antiscalant of the present invention is entirely composed of organic compounds, does not contain metal and ash, has no side effect on the catalyst, and does not affect the normal production and product quality of the device.

Before the antiscalant of the present invention is applied to the raw material heat exchanger of the S Zorb gasoline desulfurization device, the frequency of disassembly and cleaning of the catalytic gasoline heat exchanger is reduced, and the processing capacity of the S Zorb gasoline adsorption desulfurization device is improved. The antiscalant has anti-oxidation and anti-polymerization capabilities; this antiscalant can effectively inhibit the coking of heat exchange systems, pipelines, heat exchangers and other equipment before being applied to the raw material heat exchanger, so as to ensure the safe and stable operation of the device and prolong the operation of the device. cycle.

Since the raw catalytic gasoline contains colloids and olefins, the colloids will gather on the tube bundle of the heat exchanger during the heat exchange and heating process, and some olefins will condense into coke-like and adhere to the heat exchanger during the heating and gasification process, thus The heat transfer efficiency is reduced and the processing capacity of the device is affected. Adding the antiscalant of the invention to the raw material catalytic gasoline can avoid colloid aggregation and olefin condensation reaction in the gasoline, and effectively prevent heat exchanger tube bundle fouling.

Description of drawings

Fig. 1 is a schematic diagram of a scale inhibition rate test device of a scale inhibitor, wherein 1 is a raw material tank; 2 is a raw material receiving tank; 3 is a heating furnace; 4 is a scale thermal resistance test tube; 5 is a thermometer on the outer wall of the test tube; 7 is an inlet thermometer; 8 is a raw oil pump;

Figure 2 is a schematic diagram of the application of the antiscalant prepared by the present invention, wherein 1 is the antiscalant tank, 2 is the injection pump, 3 is the raw oil pump, and 4 and 5 are two sets of raw gasoline heat exchangers connected in parallel.

Detailed ways

The technical solution of the present invention is specifically described below in the form of examples, but the following examples do not limit the scope of the present invention.

Experimental material, source in following embodiment are as follows:

Aminotriazole was purchased from Jinzhou Kangtai Lubricating Oil Additive Co., Ltd.;

T154 polyisobutylene diimine, purchased from Jinzhou Kangtai Lubricating Oil Additive Co., Ltd.;

Oil-soluble imidazoline was purchased from Wuhan National Paint Co., Ltd.;

200# solvent oil was purchased from Tianjin Xinkuan Chemical Co., Ltd.

Embodiment 1 Antioxidant of the present invention, polymerization inhibitor---preparation of secondary octylphenol

The anti-oxidant and polymerization inhibitor of the present invention--second-octylphenol is formed by condensation of phenol and second-octanol, wherein the molar ratio between phenol and second-octanol is 1:2.

The antioxidant and polymerization inhibitor is formed by condensation of phenol and sec _- octanol under the action of catalyst _Al2O3 . Specifically, add secondary octanol, phenol, and catalyst _Al2O3 to the reactor, wherein the molar ratio of phenol to secondary octanol is 1: ₂ , and the catalyst _Al2O3 accounts for ₂₀ % of the total mass of the reaction material, and stir Raise the temperature to a reaction temperature of 150°C, maintain the reaction temperature, react for 5 hours, and distill the filtrate under reduced pressure (pressure 1.0×10 ^-1 Pa) to obtain a product at a temperature of 130±5°C with a yield of 85%.

The reaction formula is as follows:

Embodiment 2 Antioxidant of the present invention, polymerization inhibitor---preparation of secondary octylphenol

The anti-oxidant and polymerization inhibitor of the present invention--second-octylphenol is formed by condensation of phenol and second-octanol, wherein the molar ratio between phenol and second-octanol is 1:1.

The antioxidant and polymerization inhibitor is formed by condensation of phenol and sec _- octanol under the action of catalyst _Al2O3 . Specifically, add secondary octanol, phenol, and catalyst _Al2O3 to the reactor, wherein the molar ratio of phenol to secondary octanol is ₁ : ₁ , and the catalyst _Al2O3 accounts for 10% of the total mass of the reaction material, and stir Raise the temperature to the reaction temperature of 100°C, keep the reaction temperature, react for 1h, and distill the filtrate under reduced pressure (pressure 1.0×10 ² pa) to obtain the product with a temperature of 130±5°C, with a yield of 82%.

The reaction formula is as follows:

Embodiment 3 Antioxidant of the present invention, polymerization inhibitor---preparation of secondary octylphenol

The anti-oxidant and polymerization inhibitor of the present invention——sec-octylphenol is formed by condensation of phenol and sec-octanol, wherein the molar ratio between phenol and sec-octanol is 2:1.

The antioxidant and polymerization inhibitor is formed by condensation of phenol and sec _- octanol under the action of catalyst _Al2O3 . Specifically, add secondary octanol, phenol, and catalyst _Al2O3 to the reactor, wherein the molar ratio of phenol to secondary octanol is ₂ : ₁ , and the catalyst _Al2O3 accounts for 40% of the total mass of the reaction material, stirring Raise the temperature to a reaction temperature of 150°C, maintain the reaction temperature, react for 15 hours, and distill the filtrate under reduced pressure (pressure 1.3×10 ^-1 Pa) to obtain a product at a temperature of 130±5°C with a yield of 80%.

The reaction formula is as follows:

Embodiment 4 is applicable to the antiscalant of S Zorb gasoline desulfurization unit of the present invention

The formula of the antiscalant that is applicable to S Zorb gasoline desulfurization unit of the present invention is as follows, and wherein percentage composition is mass percent composition:

According to the above-mentioned formula ratio, each raw material is mixed using a homogenizer to obtain the scale inhibitor suitable for S Zorb gasoline desulfurization device of the present invention.

Embodiment 5 The antiscalant that is applicable to S Zorb gasoline desulfurization unit of the present invention

The formula of the antiscalant that is applicable to S Zorb gasoline desulfurization unit of the present invention is as follows, and wherein percentage composition is mass percentage composition:

According to the above-mentioned formula ratio, each raw material is mixed using a homogenizer to obtain the scale inhibitor suitable for S Zorb gasoline desulfurization device of the present invention.

Embodiment 6 is applicable to the antiscalant of S Zorb gasoline desulfurization unit of the present invention

The formula of the antiscalant that is applicable to S Zorb gasoline desulfurization unit of the present invention is as follows, and wherein percentage composition is mass percentage composition:

According to the above-mentioned formula ratio, each raw material is mixed using a homogenizer to obtain the scale inhibitor suitable for S Zorb gasoline desulfurization device of the present invention.

Embodiment 7 is applicable to the antiscalant of S Zorb gasoline desulfurization unit of the present invention

The formula of the antiscalant that is applicable to S Zorb gasoline desulfurization unit of the present invention is as follows, and wherein percentage composition is mass percentage composition:

According to the above-mentioned formula ratio, each raw material is mixed using a homogenizer to obtain the scale inhibitor suitable for S Zorb gasoline desulfurization device of the present invention.

Embodiment 8 Performance evaluation of the scale inhibitor applicable to S Zorb gasoline desulfurization unit of the present invention

1. Devices and instruments

Figure 1 and Figure 2 show the scale inhibition rate test device of the scale inhibitor and the application schematic diagram of the scale inhibitor.

2. Test method and steps

The thermal resistance to fouling was measured by heat transfer measurement. The raw material is sent from the storage tank to the fouling thermal resistance test tube by the raw oil pump, and the flow rate V and temperature _t0 of the raw material at the inlet of the test tube are kept constant. Heat the test tube with a tubular electric heating furnace with a power of 1kw.

The scaling thermal resistance in the test tube is determined by measuring and recording the temperature T of the raw material at the outlet of the test tube and calculating the heat transfer of the heating furnace to the raw material. Before the experiment, liquid paraffin and raw materials were used to calibrate the flow rate of the metering pump, and a potentiometer was used to calibrate the thermocouples on the outer wall of the test tube and the thermocouples on the inlet and outlet of raw materials. The maximum fluctuation range of the outer wall temperature of the test tube is 200±1°C, and the maximum fluctuation range of the raw material inlet temperature is 30±1°C.

3. The principle of heat transfer heat measurement method for scaling thermal resistance

The heat flux q _o at the beginning of the experiment is:

${\mathrm{<span\; class="notranslate">\; q</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; Qc</span>}}{\mathrm{<span\; class="notranslate">\; A</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; m</span>}\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; Cp</span>}}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; t</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; )</span>}{\mathrm{<span\; class="notranslate">\; A</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>$

At the beginning of the experiment, the test tube is in a clean state, and the total thermal resistance is:

$\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; Uc</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; c</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; w</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; c</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; \&Delta;</span>}{\mathrm{<span\; class="notranslate">\; t</span>}}_{\mathrm{<span\; class="notranslate">\; c</span>}}}{{\mathrm{<span\; class="notranslate">\; q</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}}<span\; class="notranslate">\; =</span>\frac{<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; t</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; )</span>}{\mathrm{<span\; class="notranslate">\; ln</span>}<span\; class="notranslate">\; (</span>\frac{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; t</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}}{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}}<span\; class="notranslate">\; )</span>}<span\; class="notranslate">\; /</span>{\mathrm{<span\; class="notranslate">\; q</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span>$

The heat flux q _t at any time t is:

${\mathrm{<span\; class="notranslate">\; q</span>}}_{\mathrm{<span\; class="notranslate">\; t</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; Q</span>}}{\mathrm{<span\; class="notranslate">\; A</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; m</span>}\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; Cp</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; T</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; t</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; )</span>}{\mathrm{<span\; class="notranslate">\; A</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 3</span>}<span\; class="notranslate">\; )</span>$

After a period of time t, there is scaling thermal resistance in the test tube, and the total thermal resistance is:

$\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; f</span>}}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}\mathrm{<span\; class="notranslate">\; f</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; f</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; w</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; f</span>}\mathrm{<span\; class="notranslate">\; 2</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; f</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; \&Delta;</span>}{\mathrm{<span\; class="notranslate">\; t</span>}}_{\mathrm{<span\; class="notranslate">\; f</span>}}}{{\mathrm{<span\; class="notranslate">\; q</span>}}_{\mathrm{<span\; class="notranslate">\; t</span>}}}<span\; class="notranslate">\; =</span>\frac{<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; t</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; T</span>}<span\; class="notranslate">\; )</span>}{\mathrm{<span\; class="notranslate">\; ln</span>}<span\; class="notranslate">\; (</span>\frac{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; t</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}}{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; T</span>}}<span\; class="notranslate">\; )</span>}<span\; class="notranslate">\; /</span>{\mathrm{<span\; class="notranslate">\; q</span>}}_{\mathrm{<span\; class="notranslate">\; t</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 4</span>}<span\; class="notranslate">\; )</span>$

In general, scaling has little effect on convective heat transfer resistance, that is, R1C=R1f,

R2c=R2f, and the thermal resistance of the outer wall of the test tube Rf2=0. (4)-(2) get:

${\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; f</span>}\mathrm{<span\; class="notranslate">\; 1</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; f</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; f</span>}}}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{{\mathrm{<span\; class="notranslate">\; u</span>}}_{\mathrm{<span\; class="notranslate">\; c</span>}}}<span\; class="notranslate">\; =</span>\frac{<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; t</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; T</span>}<span\; class="notranslate">\; )</span>}{\mathrm{<span\; class="notranslate">\; ln</span>}<span\; class="notranslate">\; (</span>\frac{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; t</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}}{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; T</span>}}<span\; class="notranslate">\; )</span>}<span\; class="notranslate">\; /</span>{\mathrm{<span\; class="notranslate">\; q</span>}}_{\mathrm{<span\; class="notranslate">\; o</span>}}<span\; class="notranslate">\; -</span>\frac{<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; t</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}<span\; class="notranslate">\; )</span>}{\mathrm{<span\; class="notranslate">\; ln</span>}<span\; class="notranslate">\; (</span>\frac{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; t</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}}{{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; T</span>}}_{\mathrm{<span\; class="notranslate">\; 0</span>}}}<span\; class="notranslate">\; )</span>}<span\; class="notranslate">\; /</span>{\mathrm{<span\; class="notranslate">\; q</span>}}_{\mathrm{<span\; class="notranslate">\; t</span>}}<span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 5</span>}<span\; class="notranslate">\; )</span>$

During the blank test (without scale inhibitor) and scale inhibitor test, measure the outer wall temperature Ts of the test tube, the raw material inlet temperature to, the test tube raw material outlet temperature T ₀ at the beginning of the test, and the test tube raw material outlet temperature T at the end of the test. The scaling thermal resistance R _f0 and R _f in the test tube can be calculated from the formulas (1), (3) and (5) in the blank test (without adding antiscalant) and in the test with antiscalant.

4. Scale inhibition rate of scale inhibitor:

If the thermal resistance of scaling in the blank experiment (without additive) is Rf0, and the thermal resistance of scaling in the experiment with antiscalant is Rf, then the scale inhibition rate F of the antiscalant is:

F＝( _Rf0 - _Rf )/ _Rf0 *100% (6)

5. Test results and discussion

1. Test raw materials

The raw material used in the test is catalytic gasoline, and its physical and chemical properties are shown in Table 1:

Table 1 Properties of catalytic gasoline

project catalytic gasoline Density (20℃), g/cm3 0.7210 Refraction(20℃) 1.4109 Distillation range (D86), ℃ 39～203 Sulfur, μg/g 1000 Mercaptan sulfur, μg/g 53 Olefins, wt% 40.59 Aromatics, wt% 23.55 Research octane number, RON 93.0 Motor octane number, MON 80.5 Bromine value, g/100g 77.23 Unwashed colloid, mg/100ml 2.5 Total chlorine, ppmw <0.5 Silicon, wppmw <0.1 Water content, mg/L 286

The olefin distribution of raw catalytic gasoline is shown in Table 2.

Table 2 Raw Catalytic Gasoline Olefin Distribution (wt%)

project μg/g Linear Olefin-1 3.54 Linear Olefin-2 25.65 Linear Olefin-3+ 3.74 branched alkenes-1 23.76 branched alkenes-2 28.36 Branched Olefin-3+ 0.29 Cyclic olefins 12.68 Diene/Triene/Alkyne 1.97 unknown 0.00 Total 100

2. Analysis of scale composition

The scale was chemically analyzed, and the results are shown in Table 3:

Table 3 Results of chemical analysis of fouling matter

Loss on ignition Ash iron in ash Toluene insoluble matter Quinoline insoluble matter m% m% m% m% m% 99.65 0.35 40.2 83.2 27.4

3. Performance evaluation of antiscalant

Under the conditions of furnace temperature 220°C, flow rate 240ml/h, raw material inlet temperature 30°C and test time 5h, conduct blank test and antiscalant test respectively, and test raw material temperature T at the furnace outlet at the beginning of the test. and the temperature T at the outlet during the 5h test, and calculate the scaling thermal resistance and scale inhibition rate according to the formulas (1), (3), (5), and (6). The results are shown in Table 4.

Table 4 Evaluation results of scale inhibitors

It can be seen from Table 4 that after the scale inhibitor of the present invention is added, the thermal resistance of the scale sample is significantly reduced, and the scale inhibition rate increases with the increase of the scale inhibitor addition. When the dosage exceeds 60ppm, the scale inhibition rate can reach over 92%.

5 Conclusion

It can be seen that the scale inhibitor of the present invention can effectively prevent raw material catalytic gasoline from fouling in the heat exchanger, and when the dosage is 60ppm, the scale inhibition rate reaches more than 92%, and the recommended dosage for industrial application is 60-80ppm .

The antiscalant should be added at the raw material feeding place, preferably at the initial stage of plant start-up. Within one month of start-up, the dosage should be 80-100ppm, and then the normal dosage should be used.

The scale inhibitor is entirely composed of organic compounds, does not contain metal and ash, has no side effects on the catalyst, and does not affect the normal production and product quality of the device.

Embodiment 9 S Zorb antiscalant of the present invention is tested to the influence of gasoline

Use 2000ml gasoline as the raw material of the device, and divide it into four equal parts. One part is the control sample, that is, no scale inhibitor is added, and the other three parts are respectively added with 60ppm, 80ppm, and 100ppm of the scale inhibitor prepared in Example 4 to analyze all the indicators of gasoline. The results are shown in the table below:

Analysis and comparison table of gasoline scale antiscalant index

Note: Iron and lead cannot be analyzed

Embodiment 10 S Zorb antiscalant of the present invention is tested on the influence of adsorbent

Take 100g of the raw catalyst, put it into the muffle furnace and burn it, the temperature is controlled at 400°C, and take a sample after burning for 1 hour; take 100g of the raw catalyst again, put it into the feed catalytic gasoline (add S Zorb antiscalant 1000ppm), Immerse the catalyst for 24 hours, filter out the gasoline with filter paper, put it into a muffle furnace and burn it at a temperature of 400°C, and take a sample after burning for 1 hour. The two samples were compared and analyzed from the composition and content of the adsorbent. The test was done three times, and the results are as follows:

It is to be understood that the invention described herein is not limited to particular methodology, protocols or reagents, as these may vary. The discussion and examples provided herein are presented for the purpose of describing particular embodiments only and are not intended to limit the scope of the invention, which is limited only by the claims.

Claims (10)

1. A scale inhibitor suitable for S Zorb gasoline desulfurization unit, the scale inhibitor comprises or is made up of following components: antioxidant, polymerization inhibitor, metal deactivator, cleaning dispersant, film forming agent and solvent. 2. antiscalant according to claim 1, is characterized in that, described antioxidant, polymerization inhibitor are formed by condensation of phenol and alcohol; Preferably, the antioxidant and polymerization inhibitor are products obtained by condensation reaction of phenol and alcohol in the presence of a catalyst, and distillation under reduced pressure after the reaction is completed. 3. antiscalant according to claim 2 is characterized in that, described phenol is selected from one or more in phenol and hydroquinone, is preferably phenol; Preferably, the alcohol is an alkyl alcohol, preferably a C _7-22 alkyl alcohol, more preferably a C _8-16 alkyl alcohol, most preferably secondary octanol; Preferably, the molar ratio between the phenol and alcohol is 1:2 to 2:1, preferably 1:2; Preferably, the catalyst is sulfuric acid or Al ₂ O ₃ , preferably Al ₂ O ₃ ; Preferably, the addition amount of the catalyst is 10-40% of the total mass of the reaction materials, preferably the addition amount of the catalyst is 20% of the total mass of the reaction materials; Preferably, the pressure of vacuum distillation is 1.0×10 ² -1.3×10 ^-1 Pa, preferably 1.0×10 ^-1 Pa; Preferably, the temperature of vacuum distillation is 100°C-150°C, preferably 130°C; Preferably, the time for vacuum distillation is 1h-15h, preferably 5h. 4. according to the scale inhibitor described in any one in claim 1 to 3, it is characterized in that, described antioxidant, polymerization inhibitor are secondary octylphenol; Preferably, the metal deactivator is selected from one or more of benzotriazole, benzotriazole, aminotriazole, preferably aminotriazole; Preferably, the cleaning and dispersing agent is polyisobutylene diimine; Preferably, the film-forming agent is morpholine or oil-soluble imidazoline, preferably oil-soluble imidazoline; Preferably, the solvent is selected from 120#, 200#, 230# solvent naphtha, preferably 200# solvent naphtha. 5. The scale inhibitor according to any one of claims 1 to 4, characterized in that, in terms of the total mass of the scale inhibitor, the mass percentage of the antioxidant and polymerization inhibitor is 10-40%, Preferably 25%; Preferably, based on the total mass of the scale inhibitor, the mass percentage of the metal passivator is 2-8%, preferably 5%; Preferably, based on the total mass of the antiscalant, the mass percentage of the cleaning and dispersing agent is 10-30%, preferably 15%; Preferably, based on the total mass of the scale inhibitor, the mass percentage of the film-forming agent is 3-10%, preferably 4%; Preferably, based on the total mass of the scale inhibitor, the mass percentage of the solvent is 30-60%, preferably 51%. 6. The antiscalant according to any one of claims 1 to 5, characterized in that, the formula of the antiscalant is as follows, wherein percentages are mass percentages: 7. a preparation method of the scale inhibitor described in any one of claims 1 to 6, the preparation method comprises antioxidant, polymerization inhibitor, metal deactivator, cleaning dispersant, film forming agent and solvent by The step of mixing in proportion; preferably, using a homogenizer for mixing. 8. the antiscalant described in any one in claim 1 to 6 is used for the application in S Zorb gasoline desulfurization unit; Preferably, the antiscalant is applied before the raw catalytic gasoline heat exchanger, preferably mixed with raw catalytic gasoline components; More preferably, the added quality of antiscalant is 60-100ppm of raw material catalytic gasoline, preferably, within 30 days of start-up, the added quality of antiscalant is 80-100ppm of raw material catalytic gasoline, after that the added quality of antiscalant is The raw material catalytic gasoline is 60-80ppm. 9. The method for using the antiscalant according to any one of claims 1 to 6, the method comprises applying the antiscalant before the raw catalytic gasoline heat exchanger, preferably mixing with raw catalytic gasoline components. 10. the using method of the described antiscalant of claim 9 is characterized in that, the addition quality of antiscalant is 60-100ppm of raw material catalytic gasoline, preferably, within one month of starting work, the addition quality of antiscalant is The raw material catalytic gasoline is 80-100ppm, and the scale inhibitor added after that is 60-80ppm of the raw catalytic gasoline.