阅读说明：本技术 一种重油加氢处理方法 (Heavy oil hydrotreating method ) 是由 杨清河 胡大为 聂红 林建飞 孙淑玲 戴立顺 于 2018-06-30 设计创作，主要内容包括：本发明涉及一种重油加氢处理方法,包括常规重油加氢处理过程和催化剂在线恢复活性处理,当操作温度比起始温度高10℃及以上时,进行在线恢复活性处理；其中,所述在线恢复活性处理包括逐渐用携带油替换重油原料进料,替换完成之后进行活性恢复反应,然后切换重油原料进入反应器；所述起始温度为初始操作温度或最近一次恢复活性处理之后的操作温度；所述携带油中含有添加剂,所述添加剂为具有供氢作用和\或溶解积炭作用的有机物。本发明所述方法在催化剂活性降低时,通过在线活性恢复处理,对催化剂进行在线活性恢复,可显著降低催化剂表面积炭,有效恢复催化剂活性,提高了催化剂利用率,显著延长运转周期,经济效益明显。(The invention relates to a heavy oil hydrotreating method, which comprises a conventional heavy oil hydrotreating process and catalyst on-line activity recovery treatment, wherein when the operating temperature is higher than the initial temperature by 10 ℃ or above, the on-line activity recovery treatment is carried out; the on-line activity recovery treatment comprises the steps of gradually replacing heavy oil raw material feed with carrying oil, carrying out activity recovery reaction after replacement is finished, and then switching the heavy oil raw material to enter a reactor; the starting temperature is the initial operating temperature or the operating temperature after the last reviving treatment; the carrying oil contains an additive which is an organic matter with the functions of hydrogen supply and/or carbon deposit dissolution. When the activity of the catalyst is reduced, the method carries out online activity recovery on the catalyst through online activity recovery treatment, can obviously reduce the carbon deposit on the surface of the catalyst, effectively recover the activity of the catalyst, improve the utilization rate of the catalyst, obviously prolong the operation period and have obvious economic benefit.)

1. A heavy oil hydrotreating method comprises a conventional heavy oil hydrotreating process and a catalyst on-line activity recovery treatment, wherein when the operation temperature is higher than the initial temperature by 10 ℃ or more, the on-line activity recovery treatment is carried out; the on-line activity recovery treatment comprises the steps of gradually replacing heavy oil raw material feed with carrying oil, carrying out activity recovery reaction after replacement is finished, and then switching the heavy oil raw material to enter a reactor; the starting temperature is the initial operating temperature or the operating temperature after the last reviving treatment; the carrying oil contains an additive which is an organic matter with the functions of hydrogen supply and/or carbon deposit dissolution.

2. The method of claim 1, the conventional heavy oil hydroprocessing process comprising contacting a heavy oil feedstock with a heavy oil hydroprocessing catalyst under heavy oil hydroprocessing conditions comprising: the hydrogen partial pressure is 6-20MPa, the temperature is 300-^-1The volume ratio of hydrogen to oil is 600-1500.

3. The process of claim 1 wherein the heavy oil feedstock is a petroleum fraction greater than 350 ℃.

4. The method of claim 1 wherein the carrier oil is a mixture comprising VGO and an additive.

5. The method of claim 1, wherein the additive is LCO and \ or HCO.

6. The process of claim 5, wherein the total amount of aromatics in the LCO is not less than 65 wt.%, preferably not less than 70 wt.%; the total amount of aromatics in the HCO is not less than 70 wt.%, preferably not less than 80 wt.%.

7. Method according to any one of claims 1, 5 and 6, wherein the additive is present in an amount of 10-80 wt.%, preferably 20-65 wt.%, based on the total amount of carrier oil.

8. The method of claim 1 wherein said progressively replacing the heavy oil feedstock feed with the carrier oil means that the proportion of heavy oil feedstock in the feed is progressively reduced while maintaining the feed volume substantially constant, the replacement feedstock being the carrier oil, until the heavy oil feedstock feed volume is zero; the rate of reduction of the heavy oil feedstock proportion is from 3 to 30 wt%/hour, based on the total feed.

9. The method as claimed in claim 1, wherein the temperature of the catalyst bed is gradually reduced from the normal operation temperature to 280-360 ℃ at a rate of 5-15 ℃/hr during the gradual replacement of the heavy oil feedstock with the carrier oil.

10. The method of claim 1, wherein the operating conditions of the reaction comprise: the hydrogen partial pressure is 5-20MPa, the temperature is 280-350 ℃, and the liquid hourly space velocity is 0.1-1.0h^-1The volume ratio of hydrogen to oil is 500-2000 and the reaction time is 18-150 hours; preferably, the operating conditions of the reaction include: the hydrogen partial pressure is 6-18MPa, the temperature is 300-^-1The volume ratio of hydrogen to oil is 600-1100, and the reaction time is 24-120 hours.

11. The method according to any one of claims 1 to 10, wherein the heavy oil hydrogenation catalyst is one of a protecting agent, a demetallization catalyst, a desulfurization catalyst and a carbon residue removal catalyst, or is a composite catalyst system of two or more of a protecting agent, a demetallization catalyst, a desulfurization catalyst and a carbon residue removal catalyst.

12. The method as claimed in any one of claims 1 to 11, wherein the method comprises a plurality of conventional heavy oil hydrotreating processes and/or a plurality of catalyst on-line activity recovery processes.

Technical Field

The invention relates to the field of heavy oil hydrotreating catalysts, in particular to a heavy oil hydrotreating method comprising a catalyst on-line activity recovery process.

Background

Along with the continuous shortage of crude oil resources and the continuous increase of the demand on high-quality oil products, the processing capacity of heavy and poor oil products in petrochemical enterprises is increased year by year. The heavy oil hydrotreating process can remove impurities such as metal, sulfur, nitrogen and the like in the raw materials, and can increase the yield of liquid fuel with high added value, so the heavy oil hydrotreating process is more and more widely popularized and applied. Compared with light distillate oil, heavy oil has the characteristics of high boiling point, large viscosity, complex structure and high content of heteroatoms such as sulfur, nitrogen, heavy metal and the like. These composition characteristics make the hydrogenation process difficult, especially easily cause the catalyst coking deactivation and metal poisoning deactivation, shorten the catalyst operation period. In addition, the problems of carbon deposition and coking of the catalyst and the like also bring great inconvenience to the unloading of the waste agent. The effective approach for solving the problems is to remove and convert the carbon deposit on the surface of the catalyst on line without shutdown of the device in the catalyst operation process except for developing a hydrotreating series catalyst with better activity stability, so that the activity of the catalyst is effectively recovered, and the operation period of the catalyst is prolonged; or the waste catalyst particles are not agglomerated, so that the catalyst is conveniently discharged from the reactor.

At present, the method for removing carbon deposit on the surface of a hydrotreating catalyst almost adopts a scorching treatment technology. ZL201010536144 discloses an out-of-device regeneration method. The deactivated hydrogenation catalyst is burnt under certain temperature control condition, and the treated catalyst is contacted with alkali matter containing solution and organic solution before heat treatment to restore the activity of the catalyst. However, the technology needs to discharge the catalyst after the shutdown of the device and operate outside the device, and has no operability for the residual oil hydrotreating process.

Patent ZL200710012678 discloses a method for in-vessel regeneration of a noble metal hydrogenation catalyst. After hydrocarbon feeding is stopped, heated hydrogen enters the reactor to react with the deactivated noble metal catalyst, so that the activity of the catalyst is recovered. However, the technology is only suitable for the noble metal catalyst for light hydrocarbon hydrogenation, and is not suitable for the non-noble metal catalyst for residual oil hydrogenation.

Patent ZL201110192778.3 discloses a method for extending the run length of a hydrotreater. In the stage of stable deactivation of the catalyst, raw oil is switched into cleaning oil to flush coke particles formed in a catalyst bed, a scale inhibitor is added to reduce the pressure drop of the bed, and finally a vulcanizing agent is injected into the cleaning oil to supplement and vulcanize the catalyst, so that the operation period of the catalyst is prolonged. The method has complex process and poor decarburization effect, and only coke particles among particles can be removed.

Patent ZL201010222425.9 discloses a residual oil hydrotreating method for prolonging the running period of a device, which switches residual oil into distillate oil containing a vulcanizing agent to reversely pass through a reactor without stopping working, and achieves the purposes of delaying pressure drop rise, improving material flow distribution and prolonging the running period. Although the method has a certain washing effect on the coke particles on the surface of the catalyst, the method cannot reduce the dense carbon deposit formed in the pores of the catalyst and recover the activity of the catalyst, so the method has a limited effect on prolonging the running period.

Patent ZL201110192778.3 discloses a method for prolonging the operation period of a hydrotreatment device, which comprises the steps of switching raw oil into cleaning oil on the premise of not stopping working, flushing a catalyst bed layer at a low hydrogen-oil ratio and a high space velocity, then adjusting the temperature of the bed layer, and adding a scale inhibitor and a vulcanizing agent into the cleaning oil for further flushing and supplementary vulcanization. Although the method can reduce the pressure drop of the bed layer, the dense carbon deposit formed in the pores of the catalyst cannot be removed, and the activity of the catalyst is recovered.

Disclosure of Invention

The technical problem to be solved by the invention is to provide a hydrotreating method comprising a process of recovering the activity of a catalyst on line, aiming at the defect that the operation period of the current heavy oil hydrotreating catalyst is short, so that the shutdown and the shutdown of a device are frequent, so that the operation period of the catalyst is obviously prolonged. Specifically, the present invention relates to the following:

the invention relates to a heavy oil hydrotreating method, which comprises a conventional heavy oil hydrotreating process and catalyst on-line activity recovery treatment, wherein when the operating temperature is higher than the initial temperature by 10 ℃ or above, the on-line activity recovery treatment is carried out; the on-line activity recovery treatment comprises the steps of gradually replacing heavy oil raw material feed with carrying oil, carrying out activity recovery reaction after replacement is finished, and then switching the heavy oil raw material to enter a reactor; the starting temperature is the initial operating temperature or the operating temperature after the last reviving treatment; the carrying oil contains an additive which is an organic matter with the functions of hydrogen supply and/or carbon deposit dissolution.

In the hydrotreating process, when the activity of the catalyst is normal, a conventional heavy oil hydrotreating process is performed, and when the activity of the catalyst does not meet the operation requirement or the operation temperature is significantly increased, the catalyst may be subjected to an online activity recovery process, thereby forming the subject matter of the present invention. By adopting the method, when the activity of the catalyst is reduced, the carbon deposit on the surface of the catalyst can be obviously reduced through the online activity recovery treatment process, the activity of the catalyst is effectively recovered, the utilization rate of the catalyst is improved, the operation period is obviously prolonged, and the economic benefit is obvious.

Detailed Description

The following detailed description of the embodiments of the present invention is provided, but it should be noted that the scope of the present invention is not limited by the embodiments.

In the present specification, anything or matters not mentioned is directly applicable to those known in the art without any change except what is explicitly stated. Moreover, any embodiment described herein may be freely combined with one or more other embodiments described herein, and the technical solutions or concepts resulting therefrom are considered part of the original disclosure or original disclosure of the invention, and should not be considered as new matters not disclosed or contemplated herein, unless a person skilled in the art would consider such a combination to be clearly unreasonable.

According to the process of the present invention, the heavy oil feedstock is conventionally selected in the art, such as atmospheric residue, vacuum residue, deep-drawn wax oil, deasphalted oil, slurry oil, etc., and preferably is a petroleum fraction at a temperature greater than 350 ℃.

The operating conditions used in the conventional heavy oil hydroprocessing process according to the process of the present invention are well known to those skilled in the art. Preferably, the hydrogen partial pressure is 6-20MPa, the temperature is 300-450 ℃, and the liquid hourly space velocity is 0.1-1h^-1The volume ratio of hydrogen to oil is 600-1500.

According to the method of the invention, the carrying oil, which preferably is a mixture containing VGO and additives, acts to carry away the carbon deposits on the catalyst surface or removed from the catalyst surface in an activity recovery reaction.

According to the method, the additive is organic matters with hydrogen supply and/or carbon deposit dissolving functions, such as common hydrogen supply agents, aromatic compounds or mixtures and the like, which are common in the field, and more specifically, the additive is preferably one or two of LCO and HCO; when both LCO and HCO are present, the weight ratio of LCO to HCO is between 0.3 and 3, preferably between 0.5 and 2; preferably, the total amount of aromatics in the catalytic light cycle oil LCO is not less than 65%, preferably not less than 70%; the total content of aromatic hydrocarbon in the catalytic heavy cycle oil HCO is not less than 70 percent, and preferably not less than 80 percent.

According to the method of the invention, the additive is preferably present in an amount of 10 to 80 wt.%, preferably 20 to 65 wt.%, based on the total amount of carrier oil.

According to the method, during the process of replacing the heavy oil raw material feed by the carrying oil, preferably, under the condition of keeping the total feed unchanged, the carrying oil dosage is controlled to be slowly increased, and meanwhile, the heavy oil feed is correspondingly reduced until the heavy oil raw material feed amount is zero; more preferably, the rate of reduction of the proportion of heavy oil feedstock is from 3 to 30 wt.%/hour, based on the total amount of feed.

In accordance with the process of the present invention, reaction conditions, such as the bed temperature of the catalyst, maintain the temperature conditions of the hydroprocessing reaction during the gradual replacement of the heavy oil feedstock with carrier oil. The inventors have found that when the catalyst bed is controlled at a suitable temperature, the catalyst activity is restored to a better level. The suitable temperature is reduced from the normal operation temperature to 280-370 ℃, more preferably 280-360 ℃, or the temperature of the catalyst bed is reduced from the normal operation temperature to at least 20 ℃ lower than the normal operation temperature, more preferably at least 40 ℃ lower; more preferably, a gradual cooling is used, e.g., at a rate of 5-15 deg.C/hr.

According to the method of the present invention, the above-mentioned raw material replacement and temperature control processes are preferably performed simultaneously.

According to the method, the reaction operation condition is a conventional operation condition, preferably the temperature is 280-360 ℃, the hydrogen partial pressure is 5-20MPa, and the liquid hourly space velocity is 0.1-1.0h^-1The volume ratio of hydrogen to oil is 500-2000 and the reaction time is 18-150 hours; further preferably, the operating conditions of the reaction are that the hydrogen partial pressure is 6-18MPa, the temperature is 300-^-1The hydrogen-oil volume ratio is 600-1100, and the reaction time is 24-120 hours, wherein the reaction time is counted from the time when the carrying oil penetrates the catalyst bed layer.

According to the method of the present invention, the switching of the feeding of the heavy oil raw material into the reactor is preferably performed while maintaining the total feeding amount substantially unchanged, and the feeding ratio of the heavy oil raw material is gradually increased, more preferably, the feeding amount of the heavy oil raw material is increased by 15 wt%/h, until the whole feeding is the heavy oil raw material.

According to the method of the invention, the temperature is preferably gradually increased to the reaction temperature during the switching of the carrying oil to the heavy oil raw material feeding, and the temperature is more preferably increased at the rate of 5-15 ℃/h.

According to the method of the present invention, preferably, the above-mentioned processes of increasing the heavy oil feedstock and adjusting the temperature to the reaction temperature are performed simultaneously.

According to the method, the heavy oil hydrogenation catalyst is a common catalyst or a catalyst combination, such as one of a protective agent, a demetallization catalyst, a desulfurization catalyst and a carbon residue removal catalyst, or a composite catalyst system of two or more of the protective agent, the demetallization catalyst, the desulfurization catalyst and the carbon residue removal catalyst.

According to the method provided by the invention, the heavy oil hydrogenation reactor can be a fixed bed, an ebullating bed or a moving bed reactor, wherein the fixed bed reactor is preferred. The reactor may be fed in either a downflow or upflow reactor. The reactor can be an independent reactor or a plurality of reactors connected in series. Each reactor can be filled with one catalyst or multiple catalysts.

According to the method provided by the invention, the heavy oil hydrogenation catalyst can have various shapes according to the use requirement, such as a spherical shape, a cylindrical shape, an annular shape, a clover shape, a four-leaf shape, a honeycomb shape or a butterfly shape; the heavy oil hydrogenation catalyst can be a supported catalyst or an unsupported catalyst according to the use requirement, can contain a molecular sieve or not, can be prepared by a special method such as a complexing agent and the like, and can also be prepared by a conventional method.

According to the method provided by the invention, during the operation of the heavy oil hydrogenation catalyst, the catalyst with reduced activity can be subjected to on-line activity recovery treatment at a proper time according to the product requirements and the device operation condition; generally, the obvious sign of the reduction of the catalyst activity is the continuous increase of the operation temperature on the premise of ensuring the product quality to reach the standard. When the operation temperature is 10 ℃ or above higher than the initial temperature, performing an online activity recovery treatment process; preferably, the on-line activity recovery treatment process is performed when the operating temperature is 10 to 40 deg.C, more preferably 15 to 25 deg.C, higher than the starting temperature. Wherein, for the catalyst which has not been subjected to the on-line activity recovery treatment process, the initial temperature refers to the initial operation temperature; for a catalyst that has been subjected to an in-line activity recovery treatment process, the starting temperature refers to the operating temperature after the last activity recovery treatment.

According to the method, one or more online activity recovery treatment processes can be carried out in the whole hydrotreating operation period according to the specific operation condition of the device.

After the activity of the catalyst is reduced to a certain degree, the method can be used for on-line activity recovery, the carbon deposit on the surface of the catalyst can be obviously reduced, the activity of the catalyst can be recovered in time, the whole operation period can be recovered for multiple times, the operation period of the catalyst can be prolonged by 30-100% due to accumulation, and the economic benefit is obvious.

The present invention will be described in further detail below by way of examples, mainly taking as examples the production of catalyst supports for the hydrogenation field, but it will be understood that the present invention is not limited to the following examples.

In the following examples and comparative examples, the measurement methods involved are as follows:

the content of nickel and vanadium in the oil sample is measured by an inductively coupled plasma emission spectrometer (ICP-AES) (the used instrument is a PE-5300 type plasma photometer of PE company in America, and the specific method is shown in petrochemical industry analysis method RIPP 124-90); measuring the sulfur content in the oil sample by using an electric quantity method (the specific method is shown in petrochemical analysis method RIPP 62-90); measuring the nitrogen content in the oil sample by an electric quantity method (the specific method is shown in petrochemical analysis method RIPP 63-90); the content of carbon residue in the oil sample is measured by a micro method (the specific method is shown in petrochemical analysis method RIPP 149-90); the content of aromatic hydrocarbon in the oil sample is determined by using a mass spectrometry method (the specific method is shown in a petrochemical analysis method RIPP 160-90).