Provided is a method for preparing synthesis gas, and more particularly, a method for preparing synthesis gas including: supplying a pyrolysis gas oil (PGO) stream including a PGO discharged from a naphtha cracking center (NCC) process to a distillation tower; and supplying a lower discharge stream from the distillation tower and a pyrolysis fuel oil (PFO) stream including a PFO discharged from the naphtha cracking center (NCC) process to a combustion chamber for a gasification process as a feed stream to obtain synthesis gas.

The invention relates to a method (100) for the recovery of a separation product which contains predominantly hydrocarbons with two carbon atoms, with the use of a separation feedstock which contains predominantly methane, hydrogen and hydrocarbons with two carbon atoms, wherein the methane content of the separation feedstock is up to 20%, and the separation feedstock is provided in a gaseous state. It is provided that, at a first pressure level, the separation feedstock is partially condensed in a single step by cooling from a first temperature level to a second temperature level, thereby obtaining precisely one first liquid fraction and precisely one first gaseous fraction; at least one part of the first gaseous fraction is partially condensed in a single step through further cooling from the second temperature level to a third temperature level, thereby obtaining precisely one second liquid fraction and precisely one second gaseous fraction; at least one part of the second gaseous fraction at the second pressure level is subjected to a contraflow absorption in the contraflow to an absorption liquid containing predominantly methane, thereby obtaining precisely one third liquid fraction and precisely one third gaseous fraction; the first, the second and the third liquid fraction are at least partially combined and, at least partially, at a second pressure level above the first pressure level, subjected to a low-temperature rectification, thereby obtaining a sump liquid and an overhead gas; at least one part of the overhead gas at the second pressure level is partially condensed in a single step through further cooling from the second temperature level to the third temperature level, thereby obtaining a fourth liquid fraction and a fourth gaseous fraction; and the absorption liquid containing predominantly methane is formed through further cooling of at least a part of the fourth gaseous fraction to a fourth temperature level. A corresponding plant also forms the subject matter of the invention.

Methods that reduce fouling of equipment in a quench water recycling loop of a steam cracker quench system by separating tar from water in the quench water recycling loop. The methods may include settling a bottom stream comprising pyrolysis gasoline, from a quench tower, in at least two quench water settlers in parallel, each of the quench water settlers producing a settler hydrocarbon stream and a settler bottom quench water stream. The methods may also include mixing a bottom stream comprising pyrolysis gasoline, from a quench tower, with quench tower effluent water to form a combined stream. The method may further include settling the combined stream in at least two quench water settlers in parallel to produce settler hydrocarbon streams, settler bottom quench water streams, and settler process water streams.

Methods and systems for producing light olefins are disclosed. A feedstock comprising crude oil is distilled to produce a plurality of streams including a naphtha stream and a vacuum residue stream. The naphtha is fed to a steam cracking unit to produce light olefins, C.sub.4 hydrocarbons, pyrolysis gasoline and pyrolysis oil. The vacuum residue stream is hydrocracked to produce additional naphtha and heavy unconverted oil. The heavy unconverted oil and the pyrolysis oil from steam cracking unit can be deasphalted to produce deasphalted oil and pitch product. The deasphalted oil can be further hydrocracked to produce naphtha. The pitch product can be gasified to produce synthesis gas, which is further used to produce methanol. The methanol can be used to react with isobutylene of the C.sub.4 hydrocarbon stream from steam cracker to produce methyl tert-butyl ether (MTBE).

A method is described for treating a hydrocarbon oil feedstream to a delayed coking unit to maximize the ratio of the yield of liquids-to-gases, and to minimize the formation of coke which includes: a. mixing an oil-soluble catalyst with the hydrocarbon oil feedstream to produce a uniform mixture; b. contacting the catalyst-containing hydrocarbon oil feedstream with an excess of hydrogen under predetermined conditions that are favorable to maximizing the solubility of the hydrogen in the feedstream in a hydrogen distribution zone that is upstream of the coking unit; c. introducing the feedstream containing the solubilized catalyst and dissolved hydrogen, and the excess hydrogen gas into a flashing zone; d. recovering from the flashing zone a hydrogen gas stream and a single-phase hydrocarbon oil feedstream containing dissolved hydrogen and catalyst; e. maintaining the hydrocarbon oil feedstream containing dissolved hydrogen and catalyst under single-phase conditions to promote the reaction of the dissolved hydrogen with free radicals formed in the feedstream and to promote the catalyzed hydrodesulfurization of any sulfur-containing compounds present in the feedstream; f. introducing the catalyst-containing feedstream into a coking furnace upstream of the coking unit to heat the feedstream to a predetermined coking temperature; g. introducing the hot feedstream into the coking unit; and h. recovering a coking unit product stream that is free of catalyst and forming a coke product that contains the catalyst.

A method of converting naphtha is disclosed. The method includes heating the naphtha in stages in different heating units. The naphtha is vaporized in the first heating unit. And the vaporized naphtha undergoes the largest temperature change of the process in the second heating unit. A third heating unit can be a part of the reactor. The reactor includes a catalyst which is contacted with the pre-heated naphtha to convert it to C.sub.2 to C.sub.4 olefins.

A method for preparing ethylene, including: passing a feed stream containing C1 and C2 hydrocarbon compounds through a first heat exchanger and feeding the feed stream passed through the first heat exchanger to a second gas-liquid separator; feeding a part of a bottom discharge stream of the second gas-liquid separator to a demethanizer, passing an overhead discharge stream of the second gas-liquid separator through a second heat exchanger, feeding the overhead discharge stream of the second gas-liquid separator passed through the second heat exchanger to a third gas-liquid separator; feeding a bottom discharge stream of the third gas-liquid separator to the demethanizer; feeding a bottom discharge stream of the demethanizer to a C2 separator; feeding an overhead discharge stream of the C2 separator to a second compressor; passing a part of a compressed discharge stream of the second compressor through the first heat exchanger and feeding the part of the compressed discharge stream of the second compressor passed through the first heat exchanger to the second compressor as a first circulation flow; passing a part of the compressed discharge stream of the second compressor through the second heat exchanger and feeding the part of the compressed discharge stream of the second compressor passed through the second heat exchanger to a first compressor as a second circulation flow; and feeding a compressed discharge stream of the first compressor to the second compressor, and an apparatus for preparing ethylene for implementing the same.

This disclosure provides systems and methods that utilize integrated mechanical vapor or thermal vapor compression to upgrade process vapors and condense them to recover the heat of condensation across multiple processes, wherein the total process energy is reduced. Existing processes that are unable to recover the heat of condensation in vapors are integrated with mechanical or thermal compressors that raise vapor pressures and temperatures sufficient to permit reuse. Integrating multiple processes permits vapor upgrading that can selectively optimize energy efficiency, environmental sustainability, process economics, or a prioritized blend of such goals. Mechanical or thermal vapor compression also alters the type of energy required in industrial processes, favoring electro-mechanical energy which can be supplied from low-carbon, renewable sources rather than combustion of carbonaceous fuels.

A process for re-refining used lubricating oil (ULO), much of which is used motor oil (UMO) relies on more rapid heating, turbulent flows, higher peak temperatures, to achieve rapid thermal cracking, even including metal-bearing additives without catalysts, compared to conventional refining of crude oil and conventional recycling processing of UMO. By thermally cracking this way and scrubbing with recycled, processed liquids from the flow stream, a process readily removes metal-bearing hydrocarbons in typical lubricating oil additives. Those bonded metals consigned to heavy fraction “bottoms,” are commonly non-removable by other recycling schemes. Long chain polymers including paraffins are broken into lighter hydrocarbons with properties typical of fuels containing olefins, naphthenes, and the like. Data and analysis reveal low solids, effective metal removal, comparatively low viscosity and boiling points, and greatly reduced sulfur content in fuel and oil products resulting.

A process for re-refining used lubricating oil (ULO), much of which is used motor oil (UMO) relies on more rapid heating, turbulent flows, higher peak temperatures, to achieve rapid thermal cracking, even including metal-bearing additives without catalysts, compared to conventional refining of crude oil and conventional recycling processing of UMO. By thermally cracking this way and scrubbing with recycled, processed liquids from the flow stream, a process readily removes metal-bearing hydrocarbons in typical lubricating oil additives. Those bonded metals consigned to heavy fraction “bottoms,” are commonly non-removable by other recycling schemes. Long chain polymers including paraffins are broken into lighter hydrocarbons with properties typical of fuels containing olefins, naphthenes, and the like. Data and analysis reveal low solids, effective metal removal, comparatively low viscosity and boiling points, and greatly reduced sulfur content in fuel and oil products resulting.