Abstract: A method is described for recovering olefins by condensation from the reaction effluent stream from a cracking furnace containing olefins and hydrogen wherein a membrane separator is employed to reject the hydrogen from the reaction effluent stream. In such a manner, the dew point temperature of the stream can be increased and the energy required to provide refrigeration for olefin condensation can be reduced. The method comprises primary condensation, vapor-liquid separation and membrane hydrogen rejection steps followed by a series of cascaded chilling and vapor-liquid separation steps. Condensate recovered is processed in a demethanizer to separate light end components. Also disclosed is an olefins plant employing a membrane separator for rejecting hydrogen to enhance the energy efficiency and/or facilitate the expansion of plant capacity.
Type:
Grant
Filed:
April 1, 1994
Date of Patent:
September 26, 1995
Inventors:
Cong X. Dinh, William C. Petterson, Ashutosh Rastogi, Vijender K. Verma
Abstract: A method and apparatus for desulfurizing a gas and regenerating a sorbent is disclosed. The sulfur-containing feed gas which can be an effluent gas from a coal gasification reactor, for example, is desulfurized with a particulated metallic oxide sorbent in a transport riser. The sulfided sorbent is than separated from a desulfurized effluent gas and regenerated by contact with an oxygen-containing gas in a transport riser. The regenerated sorbent is separated from an SO.sub.2 containing offgas and recycled to the desulfurization step. The degree of sorbent conversion in the desulfurization step is held at a low level and the sorbent regeneration rate is increased to avoid excessive temperature rise in the regeneration step. In such manner, sorbent cooling can be substantially eliminated. The regeneration riser preferably comprises a once-through lift riser to minimize the riser transport gas requirements to just oxidant gas or oxidant gas mixed with a reduced amount of diluent gas.
Type:
Grant
Filed:
March 4, 1994
Date of Patent:
September 5, 1995
Assignee:
The M. W. Kellogg Company
Inventors:
William M. Campbell, Gunnar B. Henningsen
Abstract: An integrated middle distillate upgrading process and unit are disclosed. A middle distillate side-stream of a conventional single stage hydrocracking process is circulated to a hydrotreating stage such as an aromatics saturation reactor and/or a catalytic dewaxing reactor to effect middle distillate upgrade. The upgraded product is then finished in a fractionation stage side-stripper column. The integrated hydrotreating reactor can share the duty of existing hydrocracker stage equipment and take advantage of existing process heat to eliminate the need for much of the equipment generally required by a stand-alone hydrotreating reactor of the prior art.
Abstract: An integrated process for making methanol and ammonia from a hydrocarbon feed stock and air is disclosed. An air separation unit is used to produce substantially pure oxygen and nitrogen gas streams. The oxygen gas is used in the secondary reformer to increase the operating pressure of the reformers so that compression to methanol synthesis pressure may be done by a single stage compressor. The nitrogen gas is used to remove carbon oxides impurities from a ammonia synthesis feed stream in a nitrogen wash unit in addition to supplying the nitrogen reactant in the ammonia synthesis gas. Use of nitrogen wash obviates the need for steam shift and methanation reactions used in prior art processes.
Abstract: Disclosed is a method for cracking a hydrocarbon material. The method includes introducing a stream including a hydrocarbon fluid into a reaction zone. A microwave discharge plasma is continuously maintained within the reaction zone, and in the presence of the hydrocarbon fluid. Reaction products of the microwave discharge are collected downstream of the reaction zone.
Abstract: Ammonia synthesis gas is produced by reaction of steam, an oxidant, and a major portion of fresh hydrocarbon feed in an exothermic catalytic reforming zone to a first reformed gas having very low methane content. The balance of the fresh feed is reacted with steam in an endothermic catalytic reforming zone to a second reformed gas having a low methane content. The first and second reformed gases are combined and passed in indirect heat exchange with reactants in the endothermic reforming zone to provide all of the heat required therein and are then recovered as raw ammonia synthesis gas.