2020 REFINING PROCESSES HANDBOOK PROCESS CATEGORIES COMPANY INDEX HYDROPROCESSING Hydrogenation, CDHydro® selective for refinery C4 feeds Application: To process C4 streams from refineries to produce a stream with high butylenes content that is essentially butadiene-free, suitable for methyl tertiary butyl ether (MTBE) production, butene-1 production or alkylation feed. Description: The patented C4 CDHydro process achieves selective hydrogenation of butadiene to n-butenes in a catalytic distillation column. Selective hydrogenation increases butenes available for alkylation or isomerization, reduces acid consumption in alkylation units, and greatly improves the quality of HF alkylate. The process uses commercially available catalyst in proprietary catalytic distillation structures. The unique catalytic distillation column combines reaction and fractionation in a single unit operation. This constant pressure boiling system ensures precise temperature control in the catalyst zone. Low reaction temperature and isothermal operation enhance selectivity and minimize yield losses to paraffins. Isomerization of butene-1 to butene-2 can be maximized to improve alkylate quality on HF units or minimized for increased butene-1 recovery. Refinery C4 streams are combined with hydrogen (H2 ) in the catalytic column. Treated C4 products are taken overhead. The washing action of the reflux minimizes oligomer formation, flushing heavy compounds from the catalyst and promoting long catalyst life. Excess H2 and lights are vented from the overhead drum. Economics: Capital costs are considerably lower than conventional hydrotreaters, since the single column design eliminates costs associated with fixed-bed systems. The C4 CDHydro process is typically installed in a debutanizer, either as a retrofit or in a new column. Process advantages include: * Low operating pressure * Low operating cost * High product yield (low paraffin make) * No polymer recycle across catalyst * No sweetening required CW Offgas Overhead drum Low-pressure hydrogen Treated C4s C4+ Reflux LP steam C5+ * * * * * * Essentially mercaptan sulfur-free distillate product Flexible butene-1/butene-2 ratio Retrofit to existing C4 columns All carbon steel construction Isomerization option No H2 compressor. Installation: There are more than 110 total commercially licensed CDHydro units. Licensor: Lummus Technology Contact: Technology@lummustech.com Copyright © 2020 Gulf Energy Information. All rights reserved.http://www.hydrocarbonprocessing.com/