Conversions, unit

Tests employing the less-efficient distillations, D 86, D 1160, and D 1078 are generally conducted on refined products while those giving a detailed analysis, D 2887 and D 2892, are concerned mostly with crude oils and feeds to and effluents from conversion units. 

In the 1970 s, heavy fuel came mainly from atmospheric distillation residue. Nowadays a very large proportion of this product is vacuum distilled and the distillate obtained is fed to conversion units such as catalytic cracking, visbreaking and cokers. These produce lighter products —gas and gasoline— but also very heavy components, that are viscous and have high contaminant levels, that are subsequently incorporated in the fuels. 

All modern refineries have conversion units, designed to transform black effluent streams into lighter products gas, gasoline, diesel fuel. Among these conversion units, coking processes take place by pyrolysis and push the cracking reaction so far that the residue from the operation is very heavy it is called coke . 

These compounds can be malodorous as in the case of quinoline, or they can have a plecisant odor as does indole. They decompose on heating to give organic bases or ammonia that reduce the acidity of refining catalysts in conversion units such as reformers or crackers, and initiate gum formation in distillates (kerosene, gas oil). 

The feedstocks in question are primary distillation streams and some conversion products from catalytic cracking, coking, visbreaking, and residue conversion units. 

Biedermann, J.M., J.-P. Peries and J. Bousquet (1987), SOLVAHL an attractive way to provide conversion units with high quality feedstocks . National Petroleum Refiners Association (NPRA) paper No. AM-87-41, Annual meeting, San Antonio, TX. 

The reaction is initiated with nickel carbonyl. The feeds are adjusted to give the bulk of the carbonyl from carbon monoxide. The reaction takes place continuously in an agitated reactor with a Hquid recirculation loop. The reaction is mn at about atmospheric pressure and at about 40°C with an acetylene carbon monoxide mole ratio of 1.1 1 in the presence of 20% excess alcohol. The reactor effluent is washed with nickel chloride brine to remove excess alcohol and nickel salts and the brine—alcohol mixture is stripped to recover alcohol for recycle. The stripped brine is again used as extractant, but with a bleed stream returned to the nickel carbonyl conversion unit. The neutralized cmde monomer is purified by a series of continuous, low pressure distillations. 

Figure 5. Process flow diagram of the conversion unit. (Used with permission of Simulation Sciences Inc.)...

Values of measurement in the Code text will be followed by an approximate equivalent value in SI units. Tables will have a footnote for SI conversion units used in the table. 

Commissioning of the Oryx GTL facility started in 2006 and production of the first GTL products was announced in February 2007.63 However, overproduction of a fine sediment as a result of catalyst attrition reduced throughput,64 and at the time of this writing sustained full-scale production had not yet been achieved. The syncrude resembles other LTFT syncrudes (Tables 18.2 and 18.8), and the refinery consists of a single conversion unit, namely, a hydrocracker (Figure 18.9). 

Explosion occurred in chimney connected to a conversion unit... 

A key factor in the C02 capture and storage system is the need for a functioning transportation system for the C02 captured at energy conversion units. The transport options suitable for the quantities produced by large power stations or industrial plants would mainly be pipeline transport for onshore distances and ship transport for the offshore area.6... 

Installation of more conversion equipment both in new refinery construction and as additions to existing hydroskimming facilities is already a trend. The production of more naphtha by providing new conversion units would, of course, make the additional naphtha more costly. In this connection a number of studies both our own and others (4) have attempted to determine the cost of incremental naphtha production. These indicate that in typically sized European hydroskimming refinery (operating on either Libyan or Arabian crudes) gasoline plus petrochemical naphtha yields can be increased by about 50% by installation of catalytic cracking. Based on today s prices for the other refinery products, the cost... 

The first practical conversion units came with the advent of the steamship and its requirement of fresh water for boilers. Today, most of the large ocean-going vessels have their battery of evaporators. The Forrestal class carriers of the United States Navy, for example, carry four 50,000-gallon-per-day evaporators to supply the water needs of those huge ships and their large crews. 

In newer RDS applications the hydroprocessing unit is an integral part of the overall crude oil upgrading scheme to produce transportation fuels such as gasoline and kerosene. The RDS unit may operate independently of, or in combination with, other refinery conversion units, depending on the particular feedstock and product demand (Howell et al., 1985 Siewert etal., 1985). Hydroprocessing requirements and catalyst requirements are dictated by the processing route chosen. 

A 280-nm conversion unit is available. A special thermal-isolation design results in a noise level of only 5 X 10 s AU, which makes this model the most sensitive of its type which is currently available. The detector provides a linear response over 4 orders of magnitude of... 

The Demex process selectively rejects asphaltenes, metals, and high molecular weight aromatics from vacuum residues. The resulting demetallized oil can then be combined with vacuum gas oil to give a greater availability of acceptable feed to subsequent conversion units. 

There are several possible flow scheme variations involved for this process. It can operate as an independent unit or be used in conjunction with a thermal conversion unit (Figure 9-25). In this configuration, hydrogen and a vacuum residuum are introduced separately to the heater, and mixed at the entrance to the reactor. T o avoid thermal reactions and premature coking of the catalyst, temperatures are carefully controlled and conversion is limited to approximately 70% of the total projected conversion. The removal of sulfur, heptane-insoluble materials, and metals is accomplished in the reactor. The effluent from the reactor is directed to the hot separator. The overhead vapor phase is cooled, condensed, and the hydrogen separated from there is recycled to the reactor. 

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