JP4697571B2 - Method for hydrotreating heavy hydrocarbon fractions using a sortable reactor and a reactor that can be shorted - Google Patents

Description

好適な方式では、ガード反応器またはガードゾーンで総括ＨＳＶが約０．１〜４．０ｈ^−１、通常は約０．２〜１．０ｈ^−１となるように運転するが、この点がもっと小さなガード反応器を使用する他の方法、特により小さなガード反応器を使用している米国特許第Ａ−３ ９６８ ０２６号に記載されているような方法とは差があるところである。それぞれ役目を果たしているガード反応器でのＨＳＶの値は、好ましくは約０．５〜８ｈ^−１、通常は約１〜２ｈ^−１である。ガード反応器およびそれぞれの反応器ののＨＳＶの値は、反応温度を調節しながら（発熱を制限しながら）水素化脱金属（ＨＤＭ）を最大限実施できるように選択する。
【００６２】
有利な実施態様としては、ユニットに、反応セクションとは独立して機能する循環用手段、加熱手段、冷却手段および適当な分離手段を備えたコンディショニングセクション（図示せず）を含み、それにより、配管と弁を操作することで、ガード反応器内の新触媒または再生触媒の調製操作および運転中のユニットに接続直前の短絡されていた反応器のための操作を実施できるが、すなわち、並べ替えまたは短絡中のガード反応器を予熱し、その内容物の触媒を硫化し、ガード反応器を必要な圧力および温度条件に合わせる。一連の必要な弁の操作を行ってこのガード反応器の並べ替えまたは短絡操作を実施した時に、この同一のセクションに対して、反応セクションから切り離した直後にガード反応器内の使用済み触媒をコンディショニングする操作を実施することができるが、それは、必要な条件下で使用済み触媒を洗浄およびストリッピングし、次いで冷却してから、この使用済み触媒を抜き出しさらにそれを新触媒または再生触媒と入れ替える操作を行う。
【００６３】
これらの触媒についても、本出願人による欧州特許第Ｂ−０ ０９８ ７６４号およびフランス国特許出願登録第９７／０７１４９号に記載されているものが好ましい。それらの触媒には、担体と、金属酸化物として表して０．１％〜３０重量％の、少なくとも１種の金属または周期律表の第Ｖ、ＶＩおよびＶＩＩＩ族の少なくとも１種の金属の化合物とを含み、その形状はそれぞれが複数の針状の板状微結晶から形成された複数の複数の並列配置した塊状物であって、それぞれの塊状物の板状微結晶は一般に、相互に対して、および塊状物の中心に対して放射状に配置されている。
【００６４】
より具体的には、本発明は、重質の石油または石油留分の処理に関するもので、それらをより軽質の留分に転化させて、輸送や通常の精製方法で用いられる処理を容易にすることを目的としている。石炭水素化分解により得られる油分もまた処理することができる。その場合には、沸騰床反応器を使用するのが好ましい。
【００６５】
より具体的には本発明は、金属および硫黄含量が高く、通常沸点が５２０℃を超える成分を５０％以上含む輸送が困難で高粘度の重質油を、輸送が容易で金属およびアスファルテン含量が低下し、通常沸点が５２０℃を超える成分が減少して、たとえば２０重量％未満となったような安定な炭化水素含有製品へと、変換させる場合の問題点を解決するものである。
【００６６】
具体的な実施態様においては、仕込原料をガード反応器に送るより前に、それをまず水素と混合して、水素化ビスブレーキング条件におく。
【００６７】
さらなる実施態様においては、常圧蒸留残油または減圧蒸留残油を、溶媒、たとえば炭化水素含有溶媒または溶媒混合物を用いて脱アスファルト化させることもできる。使用される頻度が最も高い炭化水素含有溶媒は、炭素原子数が３〜７の、パラフィン系、オレフィン系または脂環式炭化水素（または炭化水素混合物）である。この処理は通常、ＡＦＮＯＲ ＮＦ Ｔ６０１１５基準にしたがって、ヘプタンで沈降させることにより、脱アスファルト後の製品が含むアスファルテンを０．０５重量％未満とするような条件下で実施する。この脱アスファルト化は、本出願人による米国特許第Ａ−４ ７１５ ９４６号に記載された方法を用いて実施することができる。溶媒と仕込原料の容積比は通常約３：１から約４：１とし、総合的に脱アスファルト化をする操作に含まれるような物理化学的素操作（混合−沈降、アスファルト相のデカンテーション、アスファルト相の洗浄−沈降）を、通常は個別に実施する。次いで、この脱アスファルト後の製品を通常は、第１の機能性ガードゾーンの入口に少なくとも部分的に再循環させる。
【００６８】
アスファルテン相を洗浄するのに使用する溶媒は通常、沈降させるのに用いた溶媒と同じものである。
【００６９】
脱アスファルト化するための仕込原料と脱アスファルト化用溶媒との混合物を熱入れ替え器の上流側に通常セットするが、この熱入れ替え器は適当な沈降が起こり、良好なデカンテーションが可能となるように混合物を必要な温度に調節するためのものである。
【００７０】
仕込原料−溶媒混合物は、熱入れ替え器のチューブ側に流すのが好ましく、シェル側に流すのは好ましくない。
【００７１】
仕込原料−溶媒混合物の混合物沈降ゾーンにおける滞留時間は一般に、約５秒〜約５分であるが、好ましくは約２０秒〜約２分である。
【００７２】
この混合物のデカンテーションゾーンにおける滞留時間は通常、約４分〜約２０分である。
【００７３】
この混合物の洗浄ゾーンにおける滞留時間は一般に、約４分〜約２０分の間である。
【００７４】
デカンテーションゾーンおよび洗浄ゾーン内での混合物の上昇速度は普通、約１ｃｍ／秒未満で、好ましくは約０．５ｃｍ／秒未満である。
【００７５】
洗浄ゾーンで与える温度は普通、デカンテーションゾーンに与える温度よりも低い。この２つのゾーンでの温度の差は通常、約５℃〜約５０℃である。
【００７６】
洗浄ゾーンからの混合物は通常デカンターに、好ましくはデカンテーションゾーンの入口に位置する熱入れ替え器の上流側に再循環する。
【００７７】
洗浄ゾーンにおける溶媒対アスファルテンの比は、約０．５：１から約８：１、好ましくは約１：１から約５：１とするのがよい。
【００７８】
脱アスファルト化は２段とすることも可能で、それぞれの段に３種の素操作、すなわち沈降、デカンテーションおよび洗浄が含まれる。この厳密さを要求されるケースでは、第１段のそれぞれの操作での温度は、第２段のそれに対応する各操作での温度に比較して平均して約１０℃〜約４０℃低くするのがよい。
【００７９】
使用される溶媒は、Ｃ１〜Ｃ６のアルコールまたはフェノールまたはグリコール系の溶媒である。しかしながら、炭素原子数３〜６のパラフィン系および／またはオレフィン系溶媒を使用するのが特に有利である。
【００８０】
要約すると、１つの変形形態においては、本発明の方法は、少なくとも2つのセクションにおいて硫黄不純物および金属不純物を含有する重質炭化水素を水素化処理するための方法からなり、
そこでは、第１の水素化脱金属セクションにおいて、炭化水素の仕込原料および水素を、水素化脱金属条件下で、水素化脱金属触媒の上に通し、
次いで、その第１ステージからの流出物を、水素化脱硫条件下で、続く第２セクション中の水素化脱硫触媒の上に通し、
ここで、前記水素化脱金属セクションは１つまたは複数の水素化脱金属ゾーンを含み、それより前に、少なくとも２つの水素化脱金属ガードゾーンを直列に配置して、以下で定義するステップｂ）およびｃ）を連続してくりかえすことからなるサイクルで使用できるようにし、
前記水素化脱金属および／または水素化脱硫セクションには１基または複数の反応器が含まれ、それらは別々にまたは以下に定義するステップｄ）にしたがって、短絡することが可能であり、
前記水素化処理方法には以下のステップが含まれる：
ａ）その間はガードゾーンをすべて同時に、ガードゾーンの１つが失活する時間および／または閉塞する時間までの間に長くとも等しい時間使用するステップ；
ｂ）その間に活性低下および／または閉塞したガードゾーンを短絡し、そしてその内部の触媒を再生し、および／または新触媒もしくは再生触媒と入れ替えするステップ；
ｃ）その間にガードゾーンをすべて同時に使用するステップであり、このガードゾーンは先行ステップの間に内部の触媒を再生および／または入れ替えしたものであり、これを再接続させ、前記ステップを、ガードゾーンの１つが失活する時間および／または閉塞する時間までの間に長くとも等しい時間実施するステップ；
ｄ）サイクル中に触媒が活性低下および／または閉塞して再生および／または新触媒または再生触媒への入れ替えが必要となった時に、その間は水素化脱金属セクションおよび／または水素化脱硫セクションの反応器の少なくとも１基を短絡することが可能なステップ。
【００８１】
さらなる変形形態において、本発明の方法は、硫黄不純物および金属不純物を含有する重質炭化水素留分を、少なくとも２つのセクション中で水素化処理するための方法からなり、
そこでは、第１の水素化脱金属セクションにおいて、炭化水素の仕込原料および水素を、水素化脱金属条件下で、水素化脱金属触媒の上に通し、
次いで、その第１ステージからの流出物を、水素化脱硫条件下で、続く第２セクション中の水素化脱硫触媒の上に通し、
ここでその水素化脱金属セクションは、その前に少なくとも１つの水素化脱金属ガードゾーンがある、１つまたは複数の水素化脱金属ゾーンを含み、
前記水素化脱金属および／または水素化脱硫セクションには１基または複数の反応器が含まれ、それらは別個にまたは以下に定義するステップｄ）にしたがって、短絡することが可能であり、
前記水素化処理方法には以下のステップが含まれる：
ａ）その間はガードゾーンを、前記ゾーンが失活する時間および／または閉塞する時間までの間に長くとも等しい時間使用するステップ；
ｂ）その間に活性低下および／または閉塞したガードゾーンを短絡し、そしてその内部の触媒を再生し、および／または新触媒もしくは再生触媒と入れ替えするステップ；
ｃ）その間に先行ステップの間に内部の触媒を再生および／または入れ替えしたガードゾーンを再接続させるステップであり、前記ステップをガードゾーンの１つが失活する時間および／または閉塞する時間までの間に長くとも等しい時間実施するステップ；
ｄ）サイクル中に触媒が活性低下および／または閉塞して再生および／または新触媒または再生触媒への入れ替えが必要となった時に、その間は水素化脱金属セクションおよび／または水素化脱硫セクションの反応器の少なくとも１基を短絡することが可能なステップ。
【００８２】
さらなる変形形態において、本発明の方法は、硫黄不純物および金属不純物を含有する重質炭化水素留分を、少なくとも２つのセクション中で水素化処理するための方法からなり、
そこでは、第１の水素化脱金属セクションにおいて、炭化水素の仕込原料および水素を、水素化脱金属条件下で、水素化脱金属触媒の上に通し、
次いで、その第１セクションからの流出物を、水素化脱硫条件下で、続く第２セクション中の水素化脱硫触媒の上に通し、
ここで、前記水素化脱金属セクションは１つまたは複数の水素化脱金属ゾーンを含み、それより前に、１基または複数の反応器、好ましくは固定床または沸騰床ゾーンを含む、少なくとも２つの水素化脱金属ガードゾーンを直列に配置して、以下で定義するステップｂ）およびｃ）を連続してくりかえすことからなるサイクルで使用できるようにし、
前記水素化脱金属および／または水素化脱硫セクションには１基または複数の反応器が含まれ、それらは別々にまたは以下に定義するステップｄ）にしたがって、短絡することが可能であり、
前記水素化処理方法には以下のステップが含まれる：
ａ）その間はガードゾーンを同時にすべて、処理した仕込原料の全体の流れ方向を基準にして最も上流に位置するゾーンが失活する時間および／または閉塞する時間までの間に長くとも等しい時間使用するステップ；
ｂ）その間に、前のステップの間は最も上流側にあったガードゾーンのすぐ後ろに位置していたガードゾーンに仕込原料を直接通過させるステップであり、その間に、前のステップの間は最も上流側にあったガードゾーンを短絡して、その内部の触媒を再生し、および／または新触媒により入れ替えするステップ；および
ｃ）その間に、ガードゾーンを同時にすべて使用するステップであり、ステップｂ）の間に内部の触媒を再生および／または入れ替えしたガードゾーンをガードゾーンのセットの下流になるように再接続したステップであり、前記ステップを、このステップの間は処理した仕込原料の全体の流れ方向を基準にして最も上流に位置するゾーンが失活する時間および／または閉塞する時間までの間に長くとも等しい時間続けるステップ；
ｄ）サイクル中は、水素化脱金属セクションおよび／または水素化脱硫セクションの反応器のうちの少なくとも１基を短絡し、その間に、活性低下および／または閉塞した触媒を再生しおよび／または新触媒もしくはまたは再生触媒で入れ替えするステップ。
【００８３】
本発明の方法においては、炭化水素仕込原料の重量を基準にして一般に０．５％〜８０重量％で表される量の中間留出物を、第１の機能性ガードゾーンの入口に導入するのが好ましい。炭化水素の仕込原料と同時に導入する常圧蒸留留出物が直留ガスオイルであれば、より好ましい。
【００８４】
本発明の方法においては、水素化脱硫ステップからの製品を常圧蒸留ゾーンに送るのが好ましく、そこから常圧蒸留留出物を回収して、好ましくは少なくともその一部を第１の機能性ガードゾーンの入口に再循環させ、常圧蒸留残油を回収する。より好ましくは、水素化脱硫ステップの後の常圧蒸留ステップからのガスオイル留分の少なくとも一部を、第１の機能性ガードゾーンの入口に再循環させる。
【００８５】
本発明の方法の好ましい変形形態においては、再循環させたガスオイル留分は、初留点が約１４０℃で終留点が約４００℃の留分である。
【００８６】
これらの好適な変形形態においては、原料と同時に第１の機能性ガードゾーンの入口に導入する常圧蒸留留出物および／またはガスオイルの量は、仕込原料を基準にして約１％〜５０重量％であるのが好ましい。
【００８７】
常圧蒸留ゾーンからの常圧蒸留残油の少なくとも一部を減圧蒸留ゾーンに送ることも可能であって、そこで減圧蒸留留出物を回収し、その少なくとも一部を第１の機能性ガードゾーンの入口に再循環させ、減圧蒸留残油もまた回収する。この場合、好ましい変形形態としては、常圧蒸留残油および／または減圧蒸留留出物の少なくとも一部を接触分解ユニットに送り、そこでＬＣＯ留分とＨＣＯ留分を回収し、その２つの留分の一方、他方または混合物の少なくとも一部を第１の機能性ガードゾーンの入口に送る。
【００８８】
本発明の方法における好適な方式では、ステップｃ）の間にガードゾーンをすべて同時に使用するが、ステップｂ）で内部の触媒を再生したガードゾーンを、その接続が、ステップｂ）の間で短絡するより前の接続の仕方と同一になるように接続する。
【００８９】
本発明の方法におけるさらに好適な方式では、コンディショニングセクションを単一または複数のガードゾーンに付随させるが、このセクションによって運転中に、ユニットの運転を停止させることなく、前記の単一または複数のガードゾーンを短絡させたり並べ替えたりすることが可能となるが、前記のセクションは、稼働していないガードゾーン中の触媒をコンディショニングするために調節して、圧力が１ＭＰａ〜５ＭＰａの範囲になるようにする。
【００９０】
本発明の方法の好ましい方式では、重質油またはアスファルテン含有重質油留分からなる仕込原料を処理するために、仕込原料を単一または複数のガードゾーンに送りこむ前に、まず仕込原料を水素と混合して水素化ビスブレーキングをする条件に置く。
【００９１】
本発明の方法の好ましい方式では、任意の常圧蒸留ステップで得られた常圧蒸留残油を、溶媒または溶媒混合物を使用した脱アスファルト化にかけ、脱アスファルト後の製品の少なくとも一部を第１の機能性ガードゾーンの入口に再循環させる。
【００９２】
本発明の方法の好ましい方式では、任意の減圧蒸留ステップで得られた減圧蒸留残油を、溶媒または溶媒混合物を使用した脱アスファルト化にかけ、脱アスファルト後の製品の少なくとも一部を第１の機能性ガードゾーンの入口に再循環させる。
【００９３】
本発明の方法のさらに好ましい変形形態においては、すべての反応器が固定床反応器である。さらに好ましい変形形態では、ガード反応器および／または水素化脱金属セクションおよび／または水素化脱硫セクションのうち少なくとも１つは沸騰床反応器である。さらに好ましい変形形態では、ガードゾーンのための反応器が固定床反応器で、水素化脱硫ゾーンにおける全ての反応器が沸騰床反応器である。
【００９４】
さらに好ましい変形形態では、ガードゾーンのすべての反応器が固定床反応器であり、水素化脱金属ゾーンでのすべての反応器が沸騰床反応器であり、そして任意ではあるが好ましくは、水素化脱硫ゾーンの反応器のすべてが沸騰床反応器である。本発明の方法を、ガードゾーン中ならびに水素化脱金属および水素化脱硫セクション中で、沸騰床反応器だけで運転することも可能である。
【００９５】
【発明の実施の形態】
図１を用いて本発明を簡単に説明する。
【００９６】
仕込原料は配管１を経由してガードゾーン１Ａおよび１Ｂに到達し、配管２３および／または配管２４、配管１３を経由してこれらのゾーンから出る。単一または複数のガードゾーンを出た仕込原料は、配管１３を経由してＨＤＭセクションに到達するが、これは本明細書では反応セクション２で示されていて、１基または複数の反応器で構成されているが、そのそれぞれの反応器には専用の短絡流路が備えられている。セクション２からの流出物は、配管１４を経由して抜き出されて水素化脱硫セクション３に送られるが、これには１基または複数の反応器があるが、それらは直列に配置されていてもよく、また、そのそれぞれに専用の短絡流路を備えておいてもよい。セクション３からの流出物は配管１５を経由して抜き出される。
【００９７】
図１の中では、中間留出物が配管５５を経由して導入され、配管１の中で炭化水素の仕込原料と混合される。
【００９８】
図１で示されている場合では、ガードゾーンには２基の反応器があるが、その好ましい実施態様においては、この方法には一連のサイクルが含まれ、それぞれ、４つの連続した期（period）に分けられる：
・第１期の間は、仕込原料が連続的にゾーン１Ａ、次いでゾーン１Ｂを通過するが、ここでは、常圧蒸留から再循環させたガスオイル留分は仕込原料と共にゾーン１Ａに導入される。この第１期（方法のステップａ））の間、仕込原料は配管１および配管２１（弁３１は開）を経由してガード反応器１Ａに導入される。この期の間、弁３２、３３および３５は閉とする。ゾーン１Ａからの流出物は、配管２３、配管２６（弁３４は開）および配管２２を経由してガード反応器１Ｂに送られる。ゾーン１Ｂからの流出物は配管２４（弁３６は開）および配管１３（弁３７は開）を経由して、ＨＤＭセクション２に送られる。
【００９９】
・第２期の間は、仕込原料はゾーン１Ｂだけを通過し、常圧蒸留から再循環させたガスオイル留分は仕込原料と共にゾーン１Ｂに導入される。この第２期（方法のステップｂ））の間、弁３１、３３、３４および３５は閉とし、仕込原料は配管１および配管２２（弁３２は開）を経由してゾーン１Ｂに導入される。この期の間、ゾーン１Ｂからの流出物は配管２４（弁３６は開）および配管１３（弁３７は開）を経由して、ＨＤＭセクション２に送られる。
【０１００】
・第３期の間は、仕込原料はゾーン１Ｂ次いでゾーン１Ａを連続的に通過し、ここでは、常圧蒸留から再循環させたガスオイル留分は仕込原料と共にゾーン１Ｂに導入される。この第３期（方法のステップｃ））の間、弁３１、３４および３６は閉とし、弁３２、３３および３５は開とする。仕込原料は配管１および配管２２を経由してゾーン１Ｂに導入される。ゾーン１Ｂからの流出物は、配管２４、配管２７および配管２１を経由してガード反応器１Ａに送られる。ゾーン１Ａからの流出物は、配管２３および配管１３（弁３７は開）を経由して、ＨＤＭセクション２に送られる。
【０１０１】
・第４期の間は、仕込原料はガードゾーン１Ａだけを通過し、常圧蒸留から再循環させたガスオイル留分を仕込原料と共にゾーン１Ａに導入される。
【０１０２】
ガード反応器に対して実施するサイクルの回数は、全ユニットの運転サイクルの期間および、ゾーン１Ａおよび１Ｂの並べ替え（permutation）の平均頻度の関数である。第４期の間、弁３２、３３、３４および３６は閉とし、弁３１および３５は開とする。仕込原料は、配管１および配管２１を経由してゾーン１Ａに導入する。この期の間、ゾーン１Ａからの流出物は配管２３および配管１３（弁３７は開）を経由してＨＤＭセクション２に送られる。
【０１０３】
図１で示されている場合では、水素化脱金属（ＨＤＭ）セクション２には１基または複数の反応器を設けることができる。それらの反応器のそれぞれまたは複数は、触媒を定期的に（方法のステップｄ））するために、一時的に切り離すことができる。その好ましい実施態様において、この方法には一連のサイクルが含まれ、それぞれ、３つの連続した期に分けられる：
・第１期の間は、仕込原料を連続的にガードゾーン１Ａ、１ＢおよびＨＤＭセクション２を通過させ、最後にＨＤＳセクション３に送る。この期の間、常圧蒸留から再循環させたガスオイル留分は仕込原料と共にガードゾーン１Ａに導入される。この期の間、弁３２、３３、３５、３８および４１は閉とする。仕込原料は、配管１および配管２１を経由してゾーン１Ａに導入される。ゾーン１Ａからの流出物は、配管２３、配管２６（弁３４は開）および配管２２を経由してガードゾーン１Ｂに送られる。ゾーン１Ｂからの流出物は配管２４（弁３６は開）および配管１３（弁３７は開）を経由して、ＨＤＭセクション２に送られる。セクション２からの流出物は、配管１４（２つの弁４２および３９は開）を経由してＨＤＳセクション３に送られる。次いでセクション３からの流出物は、配管１５（弁４０は開）を経由して分留ユニット（図示せず）に送られる。
【０１０４】
・第２期の間、仕込原料は連続的にガードゾーン１Ａおよび１Ｂ、次いでＨＤＳセクション３を通過する。この期の間、常圧蒸留から再循環させたガスオイル留分は仕込原料と共にゾーン１Ｂに導入される。この運転の間は、弁３２、３３、３５、３７、４１および４２は閉とする。仕込原料は、配管１および配管２１を経由してゾーン１Ａに導入される。ゾーン１Ａからの流出物は、配管２３、配管２６（弁３４は開）および配管２２を経由してガードゾーン１Ｂに送られる。ゾーン１Ｂからの流出物は、配管２４（弁３６は開）および配管２５（２つの弁３８および３９は開）を経由してＨＤＳセクション３に送られる。次いでセクション３からの流出物は、配管１５（弁４０は開）を経由して分留ユニット（図示せず）に送られる。この期の間、ＨＤＭ触媒が新しいものと入れ替えられ、次いで、その触媒は本発明に記載された方法を使用してコンディショニングされる。このコンディショニングは、触媒が酸化物の形態をとっている場合には特に必要である。
【０１０５】
・第３期の間は、仕込原料を連続的にガードゾーン１Ａおよび１Ｂ、およびＨＤＭセクション２を通過させ、次いでＨＤＳセクション３に送る。この期の間、常圧蒸留ステップから再循環させたガスオイル留分は仕込原料と共にガードゾーン１Ｂに導入される。ここでの状態は第１期と同一で、入れ替えた新規な触媒を含む反応器を、流路系の中の、第１期について記載したのと比較して、これと同一の位置に置くことができる。
【０１０６】
図１で示されている場合では、水素化脱硫セクション３には１基または複数の反応器を設けることができ、それらの反応器のそれぞれまたは複数は、触媒を定期的に新しいものと入れ替える（方法のステップｄ））ために、一時的に切り離すことができる。その好ましい実施態様において、この方法には一連のサイクルが含まれ、それぞれ、３つの連続した期に分けられる：
・第１期の間は、仕込原料を連続的にガードゾーン１Ａ、１ＢおよびＨＤＭセクション２を通過させ、次いでＨＤＳセクション３に送る。この期の間、常圧蒸留から再循環させたガスオイル留分は仕込原料と共にガードゾーン１Ａに導入される。この期の間、弁３２、３３、３５、３８および４１は閉とする。仕込原料は、配管１および配管２１を経由してガードゾーン１Ａに導入する。ガードゾーン１Ａからの流出物は、配管２３、配管２６（弁３４は開）および配管２２を経由してガードゾーン１Ｂに送られる。ガードゾーン１Ｂからの流出物は、配管２４（弁３６は開）および配管１３（弁３７は開）を経由して、ＨＤＭセクション２に送られる。セクション２からの流出物は、配管１４（２つの弁４２および３９は開）を経由してセクション３に送られる。次いでセクション３からの流出物は、配管１５（弁４０は開）を経由して分留ユニット（図示せず）に送られる。
【０１０７】
・第２期の間、仕込原料は連続的にガードゾーン１Ａおよび１Ｂ、次いでＨＤＭセクション２を通過する。この期の間、常圧蒸留から再循環させたガスオイル留分は仕込原料と共にゾーン１Ｂに導入される。この運転の間、弁３２、３３、３５、３８、３９および４０は閉とする。仕込原料は、配管１および配管２１を経由してゾーン１Ａに導入される。ゾーン１Ａからの流出物は、配管２３、配管２６（弁３４は開）および配管２２を経由してゾーン１Ｂに送られる。ゾーン１Ｂからの流出物は、配管２４（弁３６は開）および配管１３（弁３７は開）を経由して、ＨＤＭセクション２に送られる。セクション２からの流出物は、次いで配管１４（弁４２は開）および配管１６（弁４１は開）を経由して分留ユニット（図示せず）に送られる。この期の間、セクション３からの単一または複数の触媒が新しいものと入れ替えられ、次いで、その単一または複数の触媒は本発明に記載された方法を使用してコンディショニングされる。このコンディショニングは、触媒が酸化物の形態をとっている場合には特に必要である。
【０１０８】
・第３期の間は、仕込原料を連続的にガードゾーン１Ａおよび１Ｂ、およびＨＤＭセクション２を通過させ、次いでＨＤＳセクション３に送る。この期の間、常圧蒸留ステップから再循環させたガスオイル留分は仕込原料と共にゾーン１Ｂに導入される。ここでの状態は第１期と同一で、新触媒を含む反応器を、仕込原料路系の中の、第１期について記載したのと同一の位置に置くことができる。
【図面の簡単な説明】
【図１】 本発明の一例を示すフローシートである。[0001]
[Technical field to which the invention belongs]
The present invention particularly relates to heavy hydrocarbon fractions containing sulfur impurities and metal impurities, such as atmospheric distillation residue, vacuum distillation residue, deasphalted oil, pitch, asphalt containing aromatic fraction, coal hydrocracking The refining and conversion of heavy oils from foods, various raw materials, and especially bituminous shale or bituminous sand. Specifically, the present invention relates to the processing of liquid feedstock. Asphaltenes contained in the liquid feedstock are also included in the scope of the present invention.
[0002]
[Prior art]
The feedstock that can be treated according to the invention usually contains at least 0.5 ppm by weight of metal (nickel and / or vanadium) and at least 0.5% by weight of sulfur.
[0003]
There are two purposes of catalytic hydrotreating such feedstocks: refining, ie substantially reducing the content of metals, sulfur and other impurities contained in them, and simultaneously converting them. And by increasing its hydrogen-to-carbon ratio (H / C) as a more or less lighter fraction, the resulting effluent can be converted into high quality fuel, gas oil and gasoline. Can be used as a basic raw material for producing a raw material, and a raw material for other units such as a residual oil cracking unit and a cracked vacuum distillation distillation unit.
[0004]
The cause of problems when catalytically hydrotreating such feedstocks is that such impurities gradually accumulate on the catalyst in the form of metals and coke, which rapidly reduces the activity of the catalyst system. In this case, it becomes necessary to stop the operation in order to replace the catalyst.
[0005]
Therefore, the method of hydrotreating this type of feedstock must be designed to provide as long an operating cycle as possible without shutting down the unit, and achieve an operating cycle of at least one year. Is the goal.
[0006]
There are various methods for processing this type of feedstock. Until now, such processing has been implemented in one of the following ways:
A method using a fixed catalyst bed (for example, the HYVAHL-F method of Institut Francais du Petrole) or
A method comprising at least one reactor capable of quasi-continuous replacement of the catalyst (for example the HYVAHL-M moving bed method of Institut Francais du Petrole) ).
[0007]
The method of the present invention is an improvement over prior art methods, particularly fixed bed or ebullated bed methods. In such a process, the feedstock circulates in a plurality of reactors arranged in series, preferably a fixed bed or ebullated bed reactor, while the first (single or multiple) reactors are: Specifically used to perform hydrodesulfurization (HDM) and partial hydrodesulfurization of the feedstock, and the final (single or multiple) reactor is used for deep refining of the feedstock, especially Used to perform hydrodesulfurization (HDS step). The effluent of this process is withdrawn from the last HDS reactor.
[0008]
Such a method typically uses a specific catalyst adapted to each step, but the average operating conditions are a pressure of about 5 MPa to about 25 MPa, preferably about 10 MPa to about 20 MPa, and a temperature of about 340. ° C to 440 ° C, preferably 370 ° C to 420 ° C.
[0009]
In the case of the HDM step, the ideal catalyst is suitable for processing asphaltene-rich feedstocks, yet has high metal removal performance due to its large metal holding capacity and high resistance to coking. Must. The present applicant has developed a catalyst supported on a specific porous carrier (sea urchin-like structure), and this carrier has obtained the following desirable properties for this step (Patent Document 1 and Patent Document 1). 2).
[0010]
The degree of demetallization in the HDM step is at least 10% to 90%; the metal holding capacity exceeds 10% based on the weight of the new catalyst, so that a longer operating cycle can be achieved;
· High coking resistance even at temperatures above 390 ° C, resulting in extended cycle periods often limited due to increased pressure loss and reduced activity due to coke formation However, this indicates that most of the thermal conversion reaction takes place at this step.
[0011]
In the case of the HDS step, the ideal catalyst must have a high hydrogenation capacity, thereby enabling extreme purification of the product, such as desulfurization, subsequent demetalization, Conradson carbon and possibly asphaltene reduction. Be able to implement. The Applicant has also developed such a catalyst (see US Pat. Nos. 5,057,086 and 5,048,4), which is particularly suitable for processing this type of feedstock.
[0012]
The disadvantage of such a hydrogenating catalyst is that its activity is rapidly reduced by the presence of metal or coke. For this reason, a suitable HDM catalyst capable of performing most of the conversion reaction and demetalization at a relatively high temperature, and functioning at a relatively low temperature because it is protected from metals and other impurities by the HDM catalyst. When combined with a suitable HDS catalyst that is capable of extreme hydrogenation and is less prone to coking, its refining performance is the same as the performance and temperature obtained using a single catalyst system. Ultimately, it is higher than the performance obtained using a similar HDM / HDS combination that causes rapid coking with the HDS catalyst due to the elevated pattern.
[0013]
The significance of the fixed bed method is that high purification performance can be obtained because of the high catalytic efficiency of the fixed bed. In contrast, if the amount of metal in the feed is higher than a certain level (eg 50-150 ppm), even if a high performance catalyst is used, its performance, especially the uptime in such a method And the reactor (especially the first stage HDM reactor) accumulates metal quickly and the activity decreases, and when the temperature is increased to compensate for the decrease in activity, the formation of coke is promoted. In many cases, the first stage catalyst bed becomes clogged very rapidly due to the increased pressure loss and also due to asphaltenes and sedimentary substances contained in the feedstock or as a result of operational problems.
[0014]
As a result, the unit must be shut down at least every 2-6 months and the first stage activity down or clogged catalyst bed must be replaced, and the work can take up to 3 weeks. Therefore, the operating factor of the unit is further reduced.
[0015]
The significance of the ebullated bed method is that its conversion performance is high because it can be operated at high temperature. The present applicant has developed a method that is extremely suitable for processing normal feedstocks and heavy feedstocks (see Patent Documents 5 and 6).
[0016]
Even with the optimal catalyst system, operating times can be shortened due to operational problems and / or unsuitable use for the feedstock. The unit will then stop depending on the amount of coke present in the reactor. We have continued efforts to solve these operational and catalyst use challenges.
[0017]
The inventors have also attempted to overcome the disadvantages of fixed bed arrangements from another perspective.
[0018]
As a result, one or more moving bed reactors installed before the HDM step were proposed (see Patent Document 7 or Patent Document 8). Such a moving bed may be operated in a parallel flow mode (eg, SHELL's HYCON method) or in a countercurrent mode (eg, HYVAHL-M method by the applicant). Can do. By this method, a reactor, for example a fixed bed reactor, can be protected by carrying out part of the demetalization and sieving the particles that are contained in the feedstock and can cause clogging. Furthermore, by replacing the catalyst semi-continuously in a single or multiple moving bed reactors, the unit need not be stopped every 3 to 6 months.
[0019]
The disadvantage of such moving bed technology is that the overall performance and efficiency is considerably inferior to that of the same amount of fixed bed, causing attrition to move the catalyst, and consequently downstream. Under the operating conditions where the flow in the fixed bed becomes obstructed and used, the risk of coking and the formation of catalyst agglomerates can never be ignored in the case of heavy feeds, especially when problems occur. become. The formation of such a mass obstructs the movement of the catalyst in the reactor and in the catalyst extraction pipe after use. Finally, it is necessary to shut down the unit and clean the reactor and the extraction pipe. Occurs.
[0020]
Install a guard reactor, preferably a fixed bed reactor (space velocity, HSV = 2-4) in front of the HDM reactor in order to continue to maintain excellent performance while maintaining an acceptable operating factor. Has been devised (see Patent Document 9 and Patent Document 10). Usually this guard reactor can be short-circuited by using a special isolation valve. In this way, the main reactor is protected from the risk of blockage for the time being. If the guard reactor becomes blocked, it will be short-circuited, and the next main reactor may instead be blocked instead, and the unit will have to be shut down. Furthermore, if the size of the guard reactor is small, in the case of a feedstock that is rich in metal (for example, 100 ppm or more), the feedstock cannot be sufficiently demetalized, so that the main HDM reactor is made of metal. It will not be possible to protect it sufficiently from the accumulation of the material. Eventually, in these reactors, the decrease in activity is promoted, the unit must be stopped frequently, and the operation factor becomes unsatisfactory.
[0021]
Patent Document 11 describes a system having both a good fixed bed performance and a high operation factor for processing a raw material having a high metal content (1-1500 ppm, usually 100-1000 ppm, preferably 150-350 ppm). It consists of a hydrotreating carried out in at least two stages to hydrotreat a heavy hydrocarbon fraction containing sulfur and metal impurities, where the hydrogenation in the first section In the demetallization, the hydrocarbon feedstock and hydrogen are passed over the hydrodemetallation catalyst under hydrodemetallation conditions, and then in a second step, the effluent from the first section is hydrodesulfurized conditions. Underneath the hydrodesulfurization catalyst. In this process, the hydrodemetallation section preferably consists of one or more hydrodemetallization zones of a fixed bed, but before that at least two hydrodemetallizations that are also preferably fixed beds are preferred. It has a metal guard zone and is arranged in series so that it can be used in circulation consisting of a series of steps b) and c) shown below:
a) in the meantime using the guard zone at the same time for a time until one of the guard zones is deactivated and / or closed;
b) operating with a shorted and / or blocked guard zone during the operation, and regenerating and / or replacing the internal catalyst with a new catalyst; and
c) during which the guard zone that has regenerated the catalyst during the previous step is reconnected and the guard zone is used all at the same time until one of the guard zones is deactivated and / or until it is blocked Perform the above steps.
[0022]
In this way, main HDM and HDS reactors generally have a high refining and conversion performance and can produce a stable product with a cycle period of at least 11 months. Overall desulfurization is on the order of 90% and overall demetallization is on the order of 95%.
[0023]
[Patent Document 1]
European Patent No. B-0113297.
[0024]
[Patent Document 2]
European Patent No. B-0113284.
[0025]
[Patent Document 3]
European Patent No. B-0113297.
[0026]
[Patent Document 4]
European Patent No. B-0113284.
[0027]
[Patent Document 5]
Canadian Patent No. 2171894.
[0028]
[Patent Document 6]
French patent application 98/00530.
[0029]
[Patent Document 7]
U.S. Pat. No. 3,910,834.
[0030]
[Patent Document 8]
British Patent B-2124252.
[0031]
[Patent Document 9]
U.S. Pat. No. 4,118,310.
[0032]
[Patent Document 10]
U.S. Pat. No. 3,396,026.
[0033]
[Patent Document 11]
French patent B1-2681871 specification.
[0034]
[Problem to be Solved by the Invention]
The disadvantages of this technology are that the overall desulfurization performance exceeds about 90% and / or the overall demetalization performance is difficult to exceed about 95% and regardless of performance level. It is difficult to make the cycle time exceed 11 months. Surprisingly, it has been found that short-circuiting one or more reactors of the hydrodemetallation and / or hydrodesulfurization section can maintain the catalytic activity at each step and / or improve the cycle time. It was done.
[0035]
[Means for Solving the Problems]
The present invention provides for short-circuiting of one or more reactors (ie, when a catalyst is deactivated and / or clogged by sedimentation material or coke and regenerated and / or replaced with a new or regenerated catalyst (ie, It is related to enabling (bypass). The present invention relates to both hydrodemetallation section reactors and hydrodesulfurization section reactors.
[0036]
Accordingly, if the hydrodemetallization section and / or the hydrodesulfurization section reactor is short-circuited, for example, every 6 months, and the catalyst bed that has been reduced or blocked is replaced with a new one, this operation will An improvement in the operating factor of the unit is brought about.
[0037]
The present invention is for hydrotreating a heavy hydrocarbon fraction using a first hydrodemetallation section and then a second hydrodesulfurization section that passes the effluent from the first section. It consists of a method. At least one guard zone is provided in front of the hydrodemetallation section. The hydroprocessing method includes the following steps:
a) using a guard zone in the meantime;
b) during which the guard zone is short-circuited and the catalyst therein is regenerated and / or replaced;
c) regenerating and / or reconnecting the guard zone during which the internal catalyst has been regenerated and / or replaced with a new one;
d) during which at least one of the reactors of the hydrodemetallation section and / or the hydrodesulfurization section can be short-circuited, and the catalyst inside thereof is regenerated and / or replaced with a new one.
[0038]
A method for improving the performance of a fixed bed, summarized below, is also described in French patent A-2 784 687 by the applicant. The concept there can be applied to the present invention.
[0039]
However, due to the high viscosity of the feedstock and the overall liquid effluent, the pressure loss in the reactor is high, and the operation of the circulating compressor is difficult and the hydrogen pressure is low, so that good hydrodehydration is achieved. There are problems such as failure to obtain metal or good hydrodesulfurization. Furthermore, it is known that the resulting gas oil fraction cannot usually be used directly because its sulfur content is so high that it is not allowed by current standards.
[0040]
It is therefore desirable and possible to improve the performance of the methods as described in the applicant's French patents B1-2 681 871 and A-2 784 687. Specifically, the method of the present invention can substantially reduce the viscosity of the liquid effluent, and as a result, the pressure loss inside the reactor is substantially reduced, and the circulation compressor Operation is improved and higher hydrogen pressure is obtained. As a result, the desulfurization level is generally improved and the sulfur content of the gas oil fraction is greatly reduced, so that it conforms to the current standards and can be directly added to the refinery gas oil pool. Furthermore, the method of the present invention improves the heat transfer and improves the efficiency of the preheating furnace, which makes it possible to lower the furnace wall temperature, resulting in longer furnace life and reduced unit operating costs. Will do.
[0041]
The process of the present invention combines high performance reactors, preferably fixed bed reactors or ebullated bed reactors, with a high operating factor and high metal content (1-1500 ppm, usually 100-1000 ppm, preferably 150- 350 ppm), but as one of its variants, a process for hydrotreating heavy hydrocarbon fractions containing sulfur and metal impurities in at least two sections Can be defined as
There, in a first hydrodemetallation section, a hydrocarbon feed and hydrogen are passed over a hydrodemetallation catalyst under hydrodemetallation conditions;
The effluent from the first section is then passed under hydrodesulfurization conditions over the hydrodesulfurization catalyst in the subsequent second section,
Here, the hydrodemetallization section comprises one or more hydrodemetallization zones (preferably fixed bed or ebullated bed zones), before which at least one or possibly two A hydrodemetallation guard zone (and also preferably a fixed or ebullated bed zone) is arranged in series so that it can be used in a cycle consisting of a series of repeated steps b) and c),
Said hydrodemetallation and / or hydrodesulfurization section comprises one or more reactors (preferably fixed bed or ebullated bed reactors), which are separately or according to step d) as defined below. It is possible to short circuit. When two guard zones are used, the method of the present invention is a hydroprocessing method that includes the following steps:
a) using all of the guard zones in the meantime at the same time, at most equal to the time until one of the guard zones is deactivated and / or closed.
b) short-circuiting the guard zone that has fallen and / or blocked during that time, and regenerating the catalyst therein and / or replacing it with a new or regenerated catalyst;
c) A step in which all the guard zones are used at the same time, and this guard zone is a regeneration and / or replacement of the internal catalyst during the preceding step, which is reconnected, Performing at most equal time between the time when one of the zones is deactivated and / or the time when it is occluded; and
d) during the cycle when the activity is reduced and / or clogged and it becomes necessary to regenerate and / or replace with a new or regenerated catalyst, during which time the hydrodemetallization section and / or hydrodesulfurization section reaction A step capable of shorting at least one of the vessels.
[0042]
A further variant of the process according to the invention consists of a process for hydrotreating heavy hydrocarbon fractions containing sulfur and metal impurities in at least two sections,
There, in a first hydrodemetallation section, a hydrocarbon feed and hydrogen are passed over a hydrodemetallation catalyst under hydrodemetallation conditions;
The effluent from the first step is then passed under hydrodesulfurization conditions over the hydrodesulfurization catalyst in the subsequent second section, wherein the hydrodemetallization section is preceded by at least one at least one Including one or more hydrodemetallization zones having hydrodemetallization guard zones;
Said hydrodemetallation and / or hydrodesulfurization section comprises one or more reactors, which can be short-circuited separately or according to step d) as defined below.
[0043]
The hydroprocessing method includes the following steps:
a) using the guard zone in the meantime for at most equal time between the time the zone is deactivated and / or the time to block;
b) short-circuiting the guard zone that has fallen and / or blocked during that time, and regenerating the catalyst therein and / or replacing it with a new or regenerated catalyst;
c) re-connecting the guard zone during which the internal catalyst has been regenerated and / or replaced during the preceding step, said step being between the time when one of the guard zones is deactivated and / or the time when it is blocked Performing at most equal time;
d) during the cycle when the activity is reduced and / or clogged and it becomes necessary to regenerate and / or replace with a new or regenerated catalyst, during which time the hydrodemetallization section and / or hydrodesulfurization section reaction A step capable of shorting at least one of the vessels.
[0044]
In one variant of the process of the invention, the feed for the process is a heavy hydrocarbon fraction containing sulfur and metal impurities, generally at least 0.5 ppm by weight of metal, for example A fraction obtained from vacuum distillation is called a vacuum distillation distillate (VD).
[0045]
In the process of the present invention, an amount of middle distillate, generally expressed as about 0.5% to about 80% by weight, based on the weight of the hydrocarbon feedstock, is added to the first functional guard zone. It is preferable to introduce into
[0046]
The amount of middle distillate introduced is preferably about 1% to about 50% by weight, more preferably about 5% to about 25% by weight, based on the weight of the hydrocarbon feed.
[0047]
In a specific embodiment, the atmospheric distillation distillate introduced with the hydrocarbon feed is straight-run gas oil.
[0048]
In a further embodiment, the product from the hydrodesulfurization step is sent to an atmospheric distillation zone from which an atmospheric distillation distillate is recovered and at least a portion thereof is recycled to the inlet of the first functional guard zone. Circulate and recover atmospheric distillation residue.
[0049]
In one specific variation, at least a portion of the gas oil fraction from atmospheric distillation is recycled. In this case, the gas oil fraction to be recycled is usually a fraction having an initial boiling point of about 140 ° C. and an end point of about 400 ° C. This fraction is usually a 150 to 370 ° C. fraction or a 170 to 350 ° C. fraction.
[0050]
In a further variation possible in the process of the invention, gas oil from a unit operating using the HYVAHL process or light gas oil from a catalytic cracking unit, commonly known as LCO (light cycle oil). It is possible to recycle one having an initial boiling point in the range of about 140 ° C to about 220 ° C and an end point in the range of about 340 ° C to about 400 ° C. Further, the heavy gas oil fraction from catalytic cracking is generally known as HCO (heavy cycle oil) and its initial boiling point is in the range of about 340 ° C to about 380 ° C, and its final boiling point is usually about 350 ° C to Those in the range of about 550 ° C can also be recycled.
[0051]
The amount of atmospheric distillation distillate and / or gas oil to be recycled is about 1% to 50%, preferably 5% to 25%, more preferably about 10% to 20% by weight, based on the feed. It is.
[0052]
In a further variation, at least a portion of the atmospheric distillation residue from the atmospheric distillation zone is sent to the vacuum distillation zone, from which the vacuum distillation distillate is recovered, at least a portion of which is a first functional guard. Recycled to the zone inlet, vacuum distillation residue can also be recovered and sent to the essential oil fuel pool.
[0053]
In a further variant, at least part of the atmospheric distillation residue and / or vacuum distillation distillate is used for catalytic cracking units, preferably fluid bed catalytic cracking units, for example the R2R method developed by the applicant. Send it to the unit. From this catalytic cracking unit, the LCO fraction and in particular the HCO fraction is recovered and at least part of either or the other or a mixture of the two can be added to the fresh feed, To the processing method. Usually, gas oil fractions, gasoline fractions and gas fractions are also collected. At least a portion of the gas oil fraction can optionally be recycled to the inlet of the first functional guard zone.
[0054]
The catalytic cracking step can be carried out under suitable residue cracking conditions using conventional methods well known to those skilled in the art to produce lower molecular weight hydrocarbon-containing products. The operating conditions and catalysts that can be used in fluid bed cracking are described in the following patents. That is, U.S. Pat. No. A-4 695 370, European Patent B-0 184 517, U.S. Pat. No. A-4 959 334, European Patent B-0 323 297, U.S. Pat. No. A-4 965 232. U.S. Patent No. A-5 120 691, U.S. Patent No. A-5 344 554, U.S. Patent No. A-5 449 496, European Patent No. A-0 485 259, U.S. Patent No. A-5 286 690. U.S. Patent No. A-5 324 696 and European Patent No. A-0 699 224, the disclosures of which are incorporated herein by reference.
[0055]
This fluidized bed catalytic cracking reactor may be used in either an upward flow system or a downward flow system. Although not preferred as an embodiment of the present invention, it is also possible to carry out catalytic cracking in a moving bed reactor. Particularly suitable catalytic cracking catalysts comprise at least one zeolite and are usually used in admixture with a suitable matrix such as alumina, silica or silica alumina.
[0056]
The method of the present invention also includes certain variations, in which all the guard zones are used simultaneously during step c), but when the catalyst guard zones regenerated during step b) are reconnected. In addition, the connection is made to be the same as the connection method before the short circuit between steps b).
[0057]
The method of the present invention includes further variations that constitute preferred embodiments of the present invention, which include the following steps:
a) In the meantime, all the guard zones are used at the same time, at most equal to the time until the most upstream zone is deactivated and / or clogged with respect to the overall flow direction of the processed feedstock. Step;
b) In the meantime, during the previous step, the feed material is directly passed to the guard zone located immediately behind the guard zone that was at the most upstream side. Short circuiting the guard zone that was upstream, regenerating the catalyst therein and / or replacing it with a new or regenerated catalyst; and
c) In the meantime, the step of using all the guard zones at the same time, and the step of reconnecting the guard zone in which the internal catalyst was regenerated and / or replaced during the previous step so that it is downstream of the set of guard zones. A time equal to at most equal to the time during which the most upstream zone is deactivated and / or clogged during this step, relative to the overall flow direction of the processed feedstock. Continued use step;
d) In the meantime, at least one of the reactors of the hydrodemetallation section and / or hydrodesulfurization section is short-circuited, during which time the deactivated and / or blocked catalyst is regenerated and / or a new catalyst or Or the step of replacing with a regenerated catalyst.
[0058]
In a preferred embodiment of the method, the guard zone located upstream in the direction of circulation of the entire feedstock gradually contains metals, coke, sedimentary substances, and various other impurities, so that the desired timing can be obtained. Usually, the catalyst is cut off at the timing when the catalyst in the inside is practically saturated with metal and various impurities.
[0059]
In a preferred embodiment, a specific conditioning section is used so that these guard zones can be rearranged during operation, i.e. without stopping the operation of the unit. First, using a system operated at moderate pressure (1-5 MPa, preferably 1.5-2.5 MPa), the following operations are performed on the detached guard reactor; the spent catalyst is discharged Washing, stripping, cooling; then charging with new catalyst followed by heating and sulfiding; then using appropriate operating techniques, these can be further pressurized / depressurized and cock / valve operated The guard zone is replaced efficiently without shutting down the unit and thus without affecting the operating factor, but cleaning, stripping, discharging, refilling of new catalyst, heating and sulfidation operations of these spent catalysts All are done on a separate reactor or guard zone.
[0060]
The reactor of this hydrotreating unit is usually carried out at the space velocity (HSV) shown below.
[0061]

In a preferred mode, the overall HSV is about 0.1 to 4.0 h in the guard reactor or guard zone. ^-1 , Usually about 0.2-1.0h ^-1 However, this is another way of using smaller guard reactors, particularly as described in US Pat. No. 3,968,026 using smaller guard reactors. There is a difference from the method. The value of the HSV in each guard reactor, which plays a role, is preferably about 0.5-8 h ^-1 , Usually about 1-2h ^-1 It is. The HSV values for the guard reactor and each reactor are selected to allow maximum hydrodemetallation (HDM) while adjusting the reaction temperature (with limited exotherm).
[0062]
In an advantageous embodiment, the unit comprises a conditioning section (not shown) with circulation means, heating means, cooling means and suitable separation means which function independently of the reaction section, whereby piping And the valve can be operated to prepare a new or regenerated catalyst in the guard reactor and operate for the shorted reactor just prior to connection to the operating unit, i.e., reordering or Preheat the guard reactor during short circuit, sulfidize the catalyst in its contents, and adjust the guard reactor to the required pressure and temperature conditions. Conditioning the spent catalyst in the guard reactor for this same section immediately after disconnecting from the reaction section when a series of required valve operations have been performed to perform this guard reactor reordering or short circuit operation It can be carried out by washing and stripping the spent catalyst under the required conditions, then cooling it, then extracting this spent catalyst and replacing it with a new or regenerated catalyst. I do.
[0063]
Among these catalysts, those described in European Patent No. B-0 098 764 and French Patent Application No. 97/07149 by the present applicant are preferable. These catalysts include a support and a compound of 0.1% to 30% by weight, expressed as a metal oxide, of at least one metal or at least one metal from groups V, VI and VIII of the Periodic Table. The shape is a plurality of a plurality of juxtaposed lumps each formed from a plurality of needle-like plate-like microcrystals, and each plate-like microcrystal of each lump is generally And arranged radially with respect to the center of the mass.
[0064]
More specifically, the present invention relates to the processing of heavy oils or petroleum fractions, which are converted to lighter fractions to facilitate processing used in transportation and normal refining methods. The purpose is that. Oils obtained by coal hydrocracking can also be processed. In that case, it is preferred to use an ebullated bed reactor.
[0065]
More specifically, the present invention provides a heavy oil that is difficult to transport and has a high viscosity and has a high metal and sulfur content and usually contains 50% or more of a component having a boiling point exceeding 520 ° C. This solves the problem in the case of conversion into a stable hydrocarbon-containing product that is lowered and the component whose boiling point normally exceeds 520 ° C. is reduced, for example, less than 20% by weight.
[0066]
In a specific embodiment, prior to feeding the feed to the guard reactor, it is first mixed with hydrogen and subjected to hydrogenated visbreaking conditions.
[0067]
In a further embodiment, the atmospheric distillation residue or vacuum distillation residue can be deasphalted using a solvent, such as a hydrocarbon-containing solvent or solvent mixture. The most frequently used hydrocarbon-containing solvents are paraffinic, olefinic or alicyclic hydrocarbons (or hydrocarbon mixtures) having 3 to 7 carbon atoms. This treatment is usually carried out in accordance with the AFNOR NF T60115 standard under conditions such that the asphaltene contained in the product after deasphalting is less than 0.05% by precipitation with heptane. This deasphalting can be carried out using the method described in the applicant's US Pat. No. A-4 715 946. The volume ratio of the solvent to the feedstock is usually about 3: 1 to about 4: 1 and the physicochemical operations (mixing-sedimentation, asphalt phase decantation, etc.) included in the overall deasphalting operation. The asphalt phase washing-precipitation) is usually carried out individually. This deasphalted product is then typically at least partially recycled to the inlet of the first functional guard zone.
[0068]
The solvent used to wash the asphaltene phase is usually the same solvent used for precipitation.
[0069]
The mixture of the raw material for deasphalting and the solvent for deasphalting is usually set upstream of the heat exchanger, but this heat exchanger will cause proper sedimentation and allow good decantation. In order to adjust the mixture to the required temperature.
[0070]
The feedstock-solvent mixture is preferably flowed to the tube side of the heat exchanger and is not preferably flowed to the shell side.
[0071]
The residence time of the feed-solvent mixture in the mixture settling zone is generally from about 5 seconds to about 5 minutes, preferably from about 20 seconds to about 2 minutes.
[0072]
The residence time in the decantation zone of this mixture is usually from about 4 minutes to about 20 minutes.
[0073]
The residence time of the mixture in the wash zone is generally between about 4 minutes and about 20 minutes.
[0074]
The rate of rise of the mixture within the decantation zone and the wash zone is usually less than about 1 cm / second, preferably less than about 0.5 cm / second.
[0075]
The temperature given in the washing zone is usually lower than the temperature given in the decantation zone. The temperature difference between the two zones is typically about 5 ° C to about 50 ° C.
[0076]
The mixture from the wash zone is usually recycled to the decanter, preferably upstream of the heat exchanger located at the entrance of the decantation zone.
[0077]
The solvent to asphaltene ratio in the wash zone should be from about 0.5: 1 to about 8: 1, preferably from about 1: 1 to about 5: 1.
[0078]
Deasphalting can also be in two stages, each stage including three elementary operations: sedimentation, decantation and washing. In cases where this strictness is required, the temperature in each operation of the first stage is about 10 ° C. to about 40 ° C. lower on average than the temperature in each operation corresponding to that of the second stage. It is good.
[0079]
The solvent used is a C1-C6 alcohol or phenol or glycol solvent. However, it is particularly advantageous to use paraffinic and / or olefinic solvents having 3 to 6 carbon atoms.
[0080]
In summary, in one variation, the method of the present invention comprises a method for hydrotreating heavy hydrocarbons containing sulfur and metal impurities in at least two sections;
There, in a first hydrodemetallation section, a hydrocarbon feed and hydrogen are passed over a hydrodemetallation catalyst under hydrodemetallation conditions;
The effluent from the first stage is then passed over the hydrodesulfurization catalyst in the subsequent second section under hydrodesulfurization conditions,
Wherein the hydrodemetallation section includes one or more hydrodemetallation zones, prior to which at least two hydrodemetallation guard zones are arranged in series, step b as defined below ) And c) can be used in a cycle consisting of repeated
Said hydrodemetallization and / or hydrodesulfurization section comprises one or more reactors, which can be short-circuited separately or according to step d) defined below,
The hydroprocessing method includes the following steps:
a) in the meantime using all the guard zones at the same time, at most equal to the time until one of the guard zones is deactivated and / or closed.
b) short-circuiting the guard zone that has fallen and / or blocked during that time, and regenerating the catalyst therein and / or replacing it with a new or regenerated catalyst;
c) a step in which all the guard zones are used at the same time, this guard zone being a regeneration and / or replacement of the internal catalyst during the preceding step, which is reconnected, said step being a guard zone Performing at most an equal time between the time at which one of them is deactivated and / or the time to block;
d) during the cycle when the activity is reduced and / or clogged and it becomes necessary to regenerate and / or replace with a new or regenerated catalyst, during which time the hydrodemetallization section and / or hydrodesulfurization section reaction A step capable of shorting at least one of the vessels.
[0081]
In a further variant, the process of the invention consists of a process for hydrotreating a heavy hydrocarbon fraction containing sulfur and metal impurities in at least two sections,
There, in a first hydrodemetallation section, a hydrocarbon feed and hydrogen are passed over a hydrodemetallation catalyst under hydrodemetallation conditions;
The effluent from the first stage is then passed over the hydrodesulfurization catalyst in the subsequent second section under hydrodesulfurization conditions,
Wherein the hydrodemetallation section comprises one or more hydrodemetallation zones preceded by at least one hydrodemetallation guard zone;
Said hydrodemetallation and / or hydrodesulfurization section comprises one or more reactors, which can be short-circuited separately or according to step d) defined below,
The hydroprocessing method includes the following steps:
a) in the meantime, using the guard zone for a time equal to at most the time until the zone is deactivated and / or closed;
b) short-circuiting the guard zone that has fallen and / or blocked during that time, and regenerating the catalyst therein and / or replacing it with a new or regenerated catalyst;
c) a step of reconnecting the guard zone during which the internal catalyst has been regenerated and / or replaced during the preceding step, the step being performed until one of the guard zones is deactivated and / or closed. Performing for a time equal to at most;
d) during the cycle when the activity is reduced and / or clogged and it becomes necessary to regenerate and / or replace with a new or regenerated catalyst, during which time the hydrodemetallization section and / or hydrodesulfurization section reaction A step capable of shorting at least one of the vessels.
[0082]
In a further variant, the process of the invention consists of a process for hydrotreating a heavy hydrocarbon fraction containing sulfur and metal impurities in at least two sections,
There, in a first hydrodemetallation section, a hydrocarbon feed and hydrogen are passed over a hydrodemetallation catalyst under hydrodemetallation conditions;
The effluent from the first section is then passed under hydrodesulfurization conditions over the hydrodesulfurization catalyst in the subsequent second section,
Wherein the hydrodemetallation section comprises one or more hydrodemetallization zones and preceded by at least two reactors, preferably comprising one or more reactors, preferably a fixed or ebullated bed zone. Placing the hydrodemetallation guard zones in series so that they can be used in a cycle consisting of repeating steps b) and c) defined below;
Said hydrodemetallization and / or hydrodesulfurization section comprises one or more reactors, which can be short-circuited separately or according to step d) defined below,
The hydroprocessing method includes the following steps:
a) In the meantime, all the guard zones are used at the same time, at most equal to the time until the most upstream zone is deactivated and / or clogged with respect to the overall flow direction of the processed feedstock. Step;
b) In the meantime, during the previous step, the feed material is directly passed to the guard zone located immediately behind the guard zone that was at the most upstream side. Shorting the guard zone that was upstream, regenerating the catalyst therein and / or replacing it with a new catalyst; and
c) a step in which all the guard zones are simultaneously used in the meantime, and a step in which the guard zone in which the internal catalyst is regenerated and / or replaced during step b) is reconnected so as to be downstream of the set of guard zones. And said step is continued during this step for at most equal time between the time when the most upstream zone is deactivated and / or closed, relative to the overall flow direction of the processed feedstock Step;
d) During the cycle, at least one of the reactors of the hydrodemetallation section and / or the hydrodesulfurization section is short-circuited, during which the reduced and / or blocked catalyst is regenerated and / or a new catalyst Alternatively, or replace with a regenerated catalyst.
[0083]
In the process of the present invention, an amount of middle distillate, generally expressed as 0.5% to 80% by weight, based on the weight of the hydrocarbon feedstock, is introduced into the inlet of the first functional guard zone. Is preferred. More preferably, the atmospheric distillation distillate introduced at the same time as the hydrocarbon feedstock is a straight-run gas oil.
[0084]
In the process of the present invention, it is preferred to send the product from the hydrodesulfurization step to an atmospheric distillation zone, from which the atmospheric distillation distillate is recovered and preferably at least a portion of the first functionality. Recirculate to the guard zone inlet to recover atmospheric distillation residue. More preferably, at least a portion of the gas oil fraction from the atmospheric distillation step after the hydrodesulfurization step is recycled to the inlet of the first functional guard zone.
[0085]
In a preferred variant of the process according to the invention, the recirculated gas oil fraction is a fraction with an initial boiling point of about 140 ° C. and an end point of about 400 ° C.
[0086]
In these preferred variants, the amount of atmospheric distillation distillate and / or gas oil introduced into the inlet of the first functional guard zone simultaneously with the feed is about 1% to 50 based on the feed. It is preferable that it is weight%.
[0087]
It is also possible to send at least a portion of the atmospheric distillation residue from the atmospheric distillation zone to the vacuum distillation zone, where the vacuum distillation distillate is recovered, at least a portion of which is in the first functional guard zone. Recirculate to the inlet and recover the vacuum distillation residue. In this case, a preferred variant is that at least part of the atmospheric distillation residue and / or vacuum distillation distillate is sent to the catalytic cracking unit, where the LCO fraction and the HCO fraction are recovered and the two fractions are recovered. One, the other or at least part of the mixture is sent to the entrance of the first functional guard zone.
[0088]
In a preferred manner in the method of the invention, all the guard zones are used simultaneously during step c), but the connection of the guard zone that has regenerated the internal catalyst in step b) is short-circuited during step b). Connect to be the same as the previous connection method.
[0089]
In a further preferred manner in the method of the invention, a conditioning section is associated with one or more guard zones, but this section or guards can be operated without stopping the unit during operation. Zones can be shorted and reordered, but the section can be adjusted to condition the catalyst in the guard zone that is not operating so that the pressure is in the range of 1 MPa to 5 MPa. To do.
[0090]
In a preferred mode of the process of the present invention, to process a feed consisting of heavy oil or an asphaltene-containing heavy oil fraction, before the feed is sent to one or more guard zones, the feed is first charged with hydrogen. Mix and place under conditions for hydrogenation visbreaking.
[0091]
In a preferred mode of the process of the present invention, the atmospheric distillation residue obtained in an optional atmospheric distillation step is subjected to deasphalting using a solvent or solvent mixture, and at least a portion of the product after deasphalting is first. Recirculate to the entrance of the functional guard zone.
[0092]
In a preferred mode of the method of the present invention, the vacuum distillation residue obtained in an optional vacuum distillation step is subjected to deasphalting using a solvent or solvent mixture, and at least a portion of the product after deasphalting is subjected to a first function. Recirculate to the entrance to the sex guard zone.
[0093]
In a further preferred variant of the process according to the invention, all reactors are fixed bed reactors. In a further preferred variant, at least one of the guard reactor and / or the hydrodemetallation section and / or the hydrodesulfurization section is an ebullated bed reactor. In a further preferred variant, the reactor for the guard zone is a fixed bed reactor and all reactors in the hydrodesulfurization zone are ebullated bed reactors.
[0094]
In a further preferred variant, all reactors in the guard zone are fixed bed reactors, all reactors in the hydrodemetallation zone are ebullated bed reactors, and optionally but preferably hydrogenation. All of the reactors in the desulfurization zone are ebullated bed reactors. It is also possible to operate the process according to the invention only in an ebullated bed reactor in the guard zone and in the hydrodemetallation and hydrodesulfurization section.
[0095]
DETAILED DESCRIPTION OF THE INVENTION
The present invention will be briefly described with reference to FIG.
[0096]
The raw materials reach the guard zones 1A and 1B via the pipe 1 and exit from these zones via the pipe 23 and / or the pipe 24 and the pipe 13. The feedstock leaving the single or multiple guard zones arrives at the HDM section via line 13, which is shown herein as reaction section 2 and is one or more reactors. Although configured, each reactor is provided with a dedicated short-circuit channel. The effluent from section 2 is withdrawn via line 14 and sent to hydrodesulfurization section 3, which has one or more reactors, which are arranged in series. Alternatively, each of them may have a dedicated short-circuit channel. The effluent from section 3 is withdrawn via line 15.
[0097]
In FIG. 1, the middle distillate is introduced via the pipe 55 and mixed with the hydrocarbon feed in the pipe 1.
[0098]
In the case shown in FIG. 1, there are two reactors in the guard zone, but in its preferred embodiment, the method includes a series of cycles, each of four consecutive periods. ):
-During the first period, the feedstock continuously passes through Zone 1A and then Zone 1B, but here the gas oil fraction recirculated from atmospheric distillation is introduced into Zone 1A together with the feedstock . During this first phase (step a) of the process), the feed is introduced into the guard reactor 1A via the pipe 1 and the pipe 21 (valve 31 is open). During this period, the valves 32, 33 and 35 are closed. The effluent from the zone 1A is sent to the guard reactor 1B via the pipe 23, the pipe 26 (the valve 34 is opened), and the pipe 22. The effluent from zone 1B is sent to HDM section 2 via line 24 (valve 36 open) and line 13 (valve 37 open).
[0099]
-During the second period, the feedstock passes only through zone 1B, and the gas oil fraction recirculated from atmospheric distillation is introduced into zone 1B together with the feedstock. During this second phase (method step b)), valves 31, 33, 34 and 35 are closed and the feed is introduced into zone 1B via line 1 and line 22 (valve 32 is open). . During this period, the effluent from zone 1B is sent to HDM section 2 via line 24 (valve 36 open) and line 13 (valve 37 open).
[0100]
-During the third period, the feedstock continuously passes through zone 1B and then zone 1A, where the gas oil fraction recirculated from atmospheric distillation is introduced into zone 1B together with the feedstock. During this third phase (method step c)), valves 31, 34 and 36 are closed and valves 32, 33 and 35 are open. The charged raw material is introduced into the zone 1 </ b> B via the pipe 1 and the pipe 22. The effluent from the zone 1B is sent to the guard reactor 1A via the pipe 24, the pipe 27, and the pipe 21. The effluent from zone 1A is sent to HDM section 2 via line 23 and line 13 (valve 37 open).
[0101]
-During the fourth period, the feedstock passes only through the guard zone 1A, and the gas oil fraction recirculated from atmospheric distillation is introduced into the zone 1A together with the feedstock.
[0102]
The number of cycles performed on the guard reactor is a function of the duration of the operating cycle of all units and the average frequency of permutation of zones 1A and 1B. During the fourth period, valves 32, 33, 34 and 36 are closed and valves 31 and 35 are open. The charged raw material is introduced into the zone 1 </ b> A via the pipe 1 and the pipe 21. During this period, the effluent from zone 1A is sent to HDM section 2 via line 23 and line 13 (valve 37 open).
[0103]
In the case shown in FIG. 1, the hydrodemetallation (HDM) section 2 can be provided with one or more reactors. Each or more of these reactors can be temporarily disconnected to periodically (catalyst step d)) the catalyst. In its preferred embodiment, the method includes a series of cycles, each divided into three consecutive phases:
-During the first period, the feed is continuously passed through the guard zones 1A, 1B and the HDM section 2 and finally sent to the HDS section 3. During this period, the gas oil fraction recirculated from atmospheric distillation is introduced into the guard zone 1A together with the charged raw materials. During this period, the valves 32, 33, 35, 38 and 41 are closed. The charged raw material is introduced into the zone 1 </ b> A via the pipe 1 and the pipe 21. The effluent from the zone 1A is sent to the guard zone 1B via the pipe 23, the pipe 26 (the valve 34 is opened), and the pipe 22. The effluent from zone 1B is sent to HDM section 2 via line 24 (valve 36 open) and line 13 (valve 37 open). The effluent from section 2 is sent to HDS section 3 via line 14 (two valves 42 and 39 are open). The effluent from section 3 is then sent to the fractionation unit (not shown) via line 15 (valve 40 open).
[0104]
• During the second phase, the feedstock passes continuously through guard zones 1A and 1B and then HDS section 3. During this period, the gas oil fraction recirculated from atmospheric distillation is introduced into zone 1B together with the feed. During this operation, the valves 32, 33, 35, 37, 41 and 42 are closed. The charged raw material is introduced into the zone 1 </ b> A via the pipe 1 and the pipe 21. The effluent from the zone 1A is sent to the guard zone 1B via the pipe 23, the pipe 26 (the valve 34 is opened), and the pipe 22. The effluent from zone 1B is sent to HDS section 3 via line 24 (valve 36 open) and line 25 (two valves 38 and 39 open). The effluent from section 3 is then sent to the fractionation unit (not shown) via line 15 (valve 40 open). During this phase, the HDM catalyst is replaced with a new one, which is then conditioned using the method described in the present invention. This conditioning is particularly necessary when the catalyst is in the form of an oxide.
[0105]
• During the third phase, feed is continuously passed through guard zones 1A and 1B and HDM section 2 and then sent to HDS section 3. During this period, the gas oil fraction recirculated from the atmospheric distillation step is introduced into the guard zone 1B together with the feed materials. The condition here is the same as in the first phase, and the reactor containing the replaced new catalyst is placed in the same position in the flow path system as described for the first phase. Can do.
[0106]
In the case shown in FIG. 1, the hydrodesulfurization section 3 can be provided with one or more reactors, each or more of these reactors periodically replacing the catalyst with new ones ( For method step d)), it can be temporarily disconnected. In its preferred embodiment, the method includes a series of cycles, each divided into three consecutive phases:
• During the first phase, feed is continuously passed through guard zones 1A, 1B and HDM section 2 and then sent to HDS section 3. During this period, the gas oil fraction recirculated from atmospheric distillation is introduced into the guard zone 1A together with the charged raw materials. During this period, the valves 32, 33, 35, 38 and 41 are closed. The charged raw material is introduced into the guard zone 1 </ b> A via the pipe 1 and the pipe 21. The effluent from the guard zone 1A is sent to the guard zone 1B via the pipe 23, the pipe 26 (the valve 34 is open), and the pipe 22. The effluent from the guard zone 1B is sent to the HDM section 2 via the pipe 24 (the valve 36 is opened) and the pipe 13 (the valve 37 is opened). The effluent from section 2 is sent to section 3 via line 14 (two valves 42 and 39 are open). The effluent from section 3 is then sent to the fractionation unit (not shown) via line 15 (valve 40 open).
[0107]
• During the second phase, the feedstock passes continuously through guard zones 1A and 1B and then HDM section 2. During this period, the gas oil fraction recirculated from atmospheric distillation is introduced into zone 1B together with the feed. During this operation, the valves 32, 33, 35, 38, 39 and 40 are closed. The charged raw material is introduced into the zone 1 </ b> A via the pipe 1 and the pipe 21. The effluent from the zone 1A is sent to the zone 1B via the pipe 23, the pipe 26 (the valve 34 is opened), and the pipe 22. The effluent from zone 1B is sent to HDM section 2 via line 24 (valve 36 open) and line 13 (valve 37 open). The effluent from section 2 is then routed to the fractionation unit (not shown) via line 14 (valve 42 open) and line 16 (valve 41 open). During this period, the single or multiple catalysts from section 3 are replaced with new ones, and then the single or multiple catalysts are conditioned using the method described in the present invention. This conditioning is particularly necessary when the catalyst is in the form of an oxide.
[0108]
• During the third phase, feed is continuously passed through guard zones 1A and 1B and HDM section 2 and then sent to HDS section 3. During this period, the gas oil fraction recirculated from the atmospheric distillation step is introduced into zone 1B together with the feed. The conditions here are the same as in the first phase, and the reactor containing the new catalyst can be placed in the same position as described for the first phase in the feedstock path system.
[Brief description of the drawings]
FIG. 1 is a flow sheet showing an example of the present invention.

Claims (19)

A process for hydrotreating a heavy hydrocarbon fraction containing sulfur impurities and metal impurities in at least two sections, comprising:
Here, in the first hydrodemetallation section, the hydrocarbon feed and hydrogen are passed over the hydrodemetallation catalyst under hydrodemetallation conditions;
The effluent from the first stage is then passed over the hydrodesulfurization catalyst under hydrodesulfurization conditions in the subsequent second section,
Wherein the hydrodemetallation section comprises one or more hydrodemetallation zones preceded by at least one guard zone;
The hydrodesulphurization section comprises one group or more reactors which can be short-circuited according to step d) as defined below, said hydrotreatment method,
a) using one or more guard zones for a time equal to at most the time until the guard zone is deactivated and / or closed;
b) shorting the reduced and / or blocked guard zone and regenerating the catalyst therein and / or replacing it with a new or regenerated catalyst;
c) Reconnecting the guard zone that regenerated and / or replaced the internal catalyst during the preceding step, said step being at most equal to the time until one of the guard zones deactivates and / or closes Performing the time step; and
d) Short-circuiting at least one of the reactors in the hydrodesulfurization section when the catalyst loses activity and / or becomes clogged during the cycle and needs to be regenerated and / or replaced with a new or regenerated catalyst. Possible steps. One or more hydrodemetallation zones are preceded by at least two hydrodemetallation guard zones, the hydrodemetallation guard zones being arranged in series and repeating steps b) and c). Can be used in a cycle consisting of
During the steps a) and c), the guard zones are used all at the same time, at most equal to the time until one of the guard zones is deactivated and / or closed.
The hydrotreating method according to claim 1. Said hydrodemetallation guard zone comprises one or more fixed bed or ebullated bed reactors, and all of the guard zones are used simultaneously during step c), and the catalyst is regenerated and / or during step b). Alternatively, reconnect the replaced guard zone so that it is downstream of the set of guard zones, and during this step the zone located most upstream is lost with respect to the overall flow direction of the processed feedstock. Continue for at most equal time between time to live and / or time to block,
The hydrotreating method according to claim 2.   An intermediate effluent in an amount of 0.5% to 80% by weight, based on the weight of the hydrocarbon feedstock, is introduced at the inlet of the first guard zone during operation. The method of any one of these. The product from the hydrodesulfurization step is sent to an atmospheric distillation zone from which an atmospheric distillation distillate is recovered and at least a portion of it is recycled to the inlet of the first functional guard zone. The process according to any one of claims 1 to 4 , wherein the pressure distillation residue is also recovered. 6. The method of claim 5 , wherein at least a portion of the gas oil fraction from the atmospheric distillation step after the hydrodesulfurization step is recycled to the inlet of the first functional guard zone. The process according to claim 6 , wherein the initial boiling point of the recycled gas oil fraction is 140 ° C and the final boiling point is 400 ° C. The amount of the atmospheric distillation distillate and / or gas oil introduced into the inlet of the first functional guard zone simultaneously with the raw material is 1 % to 50% by weight based on the charged raw material. 8. The method according to any one of items 7 . At least a portion of the atmospheric distillation residue from the atmospheric distillation zone is sent to the vacuum distillation zone where the vacuum distillation distillate is recovered and at least a portion thereof is recycled to the inlet of the first functional guard zone. A process according to claim 5 or 6 , wherein the process is circulated and the vacuum distillation residue is also recovered. At least a portion of the atmospheric distillation residue and / or vacuum distillation distillate is sent to a catalytic cracking unit where an LCO fraction and an HCO fraction are recovered, wherein one of the two fractions, the other or a mixture of The method of claim 9 , wherein at least a portion is sent to an entrance of the first functional guard zone.   During step c), all the guard zones are used simultaneously, and the guard zone that has regenerated the internal catalyst in step b) is connected in the same way as before the short circuit during step b). The method according to any one of claims 1 to 3, wherein: A conditioning section can be attached to a single or multiple guard zones, which can be used to short circuit or reorder the single or multiple guard zones during operation without stopping the unit. 12. The method of any one of claims 1 to 11 , wherein, although possible, the section is adjusted so that the pressure is in the range of 1 MPa to 5 MPa to condition the catalyst in the guard zone that is not operating. The method described in 1. To process a feed consisting of heavy oil or heavy oil fractions containing asphaltenes, the feed is first mixed with hydrogen before hydrogenation visbreaking before it is sent to one or more guard zones. 13. A method according to any one of claims 1 to 12 , which is subject to conditions. 6. The atmospheric distillation residue is subjected to deasphalting using a solvent or solvent mixture, and at least a portion of the deasphalted product is recycled to the inlet of the first functional guard zone . 9. The method according to any one of 9 , 10 . The vacuum residue oil, subjected to deasphalting using a solvent or solvent mixture, at least a portion of the product after deasphalting is recycled to the inlet of the first functional guard zone, according to claim 9 or 10 The method described in 1. The process according to any one of claims 1 to 15 , wherein all of the reactors are fixed bed reactors. Wherein at least one of the guard zone and / or hydrodemetallization section and / or hydrodesulphurization section reactor is a boiling bed reactor, the method according to any one of claims 1-16. 18. The process of claim 17 , wherein the reactor for the guard zone is a fixed bed reactor and all reactors in the hydrodesulfurization zone are ebullated bed reactors. 19. A process according to claim 17 or 18 , wherein the reactor for the guard zone is a fixed bed reactor and all reactors in the hydrodemetallation zone are ebullated bed reactors.

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