Off-site regeneration

Ex situ or off-site, regeneration of noble metal catalysts is not commonly practiced by commercial petroleum refiners because it requires either an extended period with the process shut down or requires that a spare load of cosdy catalyst, which would only be used for a fraction of the time, be purchased and kept available. 

Ex situ or off-site, regeneration of base metal catalysts is a service offered by several vendors worldwide, including Catalyst Recovery, Inc., of Lafayette, Louisiana, and Medicine Hat, Alberta, Canada Catalyst Recovery, Europe of Rodange, Luxembourg Nippon CRI of Miyako, Japan Englehard (formerly Edtrol) of Salt Lake City, Utah Eurecat, U.S., of Pasadena, Texas and Eurecat, SA of La Voulte, Erance (22—28). 

Adsorbent can be regenerated on-site using steam stripping, thus eliminating the liability and cost of off-site regeneration or disposal. 

CONTINUOUS DEVELOPMENTS OF CATALYST OFF-SITE REGENERATION AND PRESULFIDING... 

The high quality achieved by the modem technologies of off-site regeneration often allows to perform more than one cycle with the same catalyst batch. In addition to this economic incentive for regeneration, more and more stringent environmental regulations for disposal of spent catalysts encourage their reuse. 

Check regeneration sequence at off-site regeneration facility... 

The catalyst dust is then separated from the resulting carbon dioxide stream via cyclones and/or electrostatic precipitators and is sent off-site for disposal or treatment. Generated wastewater is typically sour water from the fractionator containing some oil and phenols. Wastewater containing metal impurities from the feed oil can also be generated from the steam used to purge and regenerate catalysts. 

In the sulfuric acid process, the sulfuric acid removed must be regenerated in a sulfuric acid plant which is generally not a part of the alkylation unit and may be located off-site. Spent sulfuric acid generation is substantial typically in the range of 13 to 30 pounds per barrel of alkylate. Air emissions from the alkylation process may arise from process vents and fugitive emissions. 

Generally, adsorption, absorption, and biofilter units require more space than compact incinerators and condensers. If the plant room is restricted, a local roof-mounted system may be the best alternative. However, roof structural reinforcement may be required even for small and lightweight units. Consideration must be given to the effects of noise and vibration. Small adsorption systems, such as adsorption canisters, require an additional central regeneration unit on site, or they must be regenerated or disposed of off site. A central regeneration unit may require long runs of costly ductwork." ... 

Kranz MWS A flue-gas desulfurization system based on activated carbon. One carbon bed removes most of the sulfur dioxide. Ammonia is then injected for the SCR process to occur in the second bed, which also removes the residual sulfur dioxide. The carbon is regenerated off-site. Developed by Krantz Company, Germany. In 1986, three plants were operating in Germany. 

An additional estimated cost breakdown comes from Sandia National Laboratory. According to this source, the estimated cost breakdown is the detoxifier, 325,000 drum feeder, 50, 000 and the moving bed evaporator, 165,000. The cost of other peripherals is estimated to be 150,000. Daily operating and maintenance costs are estimated at 600,000. Life-cycle costs are 340,000 (5 years) and 270,000 (10 years). Steam reforming is approximately 75% less expensive that off-site thermal regeneration of granular activated carbon (D17028F, p. 3). 

The Terra-Kleen solvent extraction technology is an on-site, batch-process system that uses a proprietary solvent to remove hazardous organic constituents from soils. The treatment system uses a solvent regeneration system that concentrates the extracted contaminants and then recycles the extraction solvent. The treated soil can often be returned to the site. The concentrated contaminants are usually transported off-site for disposal. 

The NECDF carbon can be divided into two categories OX15 carbon has not been exposed to VX (determination based on process knowledge and prefilter analytical monitoring). The expectation is that a carbon vendor will take back this material, or that an off-site contractor will regenerate it. For the IX carbon that has been exposed to VX, the anticipation is that it will be disposed of off-site by an incineration process. 

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