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 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.

The present invention concerns a method of weakening and removal of coke or carbonaceous material which deposits as a result of thermal cracking of hydrocarbons on the inner walls of coils, piping, tubing, and in general, hydrocarbon processing equipment.

The present invention concerns a method of weakening and removal of coke or carbonaceous material which deposits as a result of thermal cracking of hydrocarbons on the inner walls of coils, piping, tubing, and in general, hydrocarbon processing equipment.

A process for steam cracking a whole crude including a volatilization step performed to maintain a relatively large hydrocarbon droplet size. The process may include contacting a whole crude with steam to volatilize a portion of the hydrocarbons, wherein the contacting of the hydrocarbon feedstock and steam is conducted at an initial relative velocity of less than 30 m/s, for example. The resulting vapor phase, including volatilized hydrocarbons and steam may then be separated from a liquid phase comprising unvaporized hydrocarbons. The hydrocarbons in the vapor phase may then be forwarded to a steam pyrolysis reactor for steam cracking of the hydrocarbons in the vapor phase.

Systems and methods for safe on-line pigging decoking of a coker furnace tubes and which also permits on-line spalling operations.

Systems and methods for safe on-line pigging decoking of a coker furnace tubes and which also permits on-line spalling operations.

Crackers for hydrocarbon such as naphtha and C.sub.2-C.sub.4 paraffins contain a radiant section and a convection section. The exhaust gases leaving the radiant section pass through the convection. Generally fouling from the convection section was low relative to fouling (e.g., coke build up) in the radiant section. With improved metallurgy and operating conditions, the time between decokes of the radiant section has increased and now there is a need to reduce fouling from the convection section. This may be achieved by using stainless steel, and particularly high nickel, high chrome stainless steel in the passes in the convection section.

Crackers for hydrocarbon such as naphtha and C.sub.2-C.sub.4 paraffins contain a radiant section and a convection section. The exhaust gases leaving the radiant section pass through the convection. Generally fouling from the convection section was low relative to fouling (e.g., coke build up) in the radiant section. With improved metallurgy and operating conditions, the time between decokes of the radiant section has increased and now there is a need to reduce fouling from the convection section. This may be achieved by using stainless steel, and particularly high nickel, high chrome stainless steel in the passes in the convection section.

The invention relates weldments useful as heat transfer tubes in pyrolysis furnaces. The invention relates to tubes that are useful in pyrolysis furnaces. The weldments include a tubular member and at least one mixing element. The tubular member comprises an aluminum-containing alloy. The mixing element comprises an aluminum-containing alloy. The mixing element's aluminum-containing alloy can be the same as or different from the tubular member's aluminum-containing alloy. Other aspects of the invention relate to pyrolysis furnaces which include such weldments, and the use of such pyrolysis furnaces for hydrocarbon conversion processes such as steam cracking.