Light cracked naphtha

Snamprogettl S.p.A. Tame/high ethers Light cracked naphtha, methanol More than 20% reactive isoamylenes, 40-60% reactive isohexene, 20-30% reactive isoheptenes etherified into TAME and higher ethers NA NA... 

Application The Snamprogetti Etherification Technology allows producing high-octane oxygenates compounds such as methyl tert-butyl ether (MTBE), ethyl tert-butyl ether (ETBE), tert-amyl methyl ether (TAME), tert-amyl ethyl ether (TAEE) and etherified light cracked naphtha (ELCN). 

Residues (petroleum), coker scrubber, condensed-ring-arom-containing Residues (petroleum), hydrogenated steam-cracked naphtha, atm tower, vacuum, light... 

Distillates (petroleum), light steam-cracked naphtha... 

Figure 5.3 shows light olefin yields of DCC process in four refineries with different feedstocks at reaction temperatures of 545-565°C. The propylene yield can reach 23 wt% with paraffinic feed, and about 18-19 wt% with intermediate-based feed. The propylene/ethylene ratio is about 3.5-6.2, much higher than that of steam cracking. The DCC operation can be modified to further increase the yield of propylene. For example, recycling a part of DCC cracked naphtha to the reactor resulted in a propylene yield increment of 3.5 wt % in Jinan Refinery [16]. 

This process is used to produce light gases, naphtha, distillate fuel, heavy fuel oil, and petroleum coke by cracking heavy residual products such as atmospheric and vacuum resids. Both delayed coking and fluid coking processes are utilized. 

Clay Treating A process used to improve the color of cracked naphthas and light distillates. It is also used to remove surface active agents which can negatively impact the WSIM rating of jet fuel. 

Feed Virgin/cracked naphtha Light cycle oil, diesel Kerosene Vacuum gas oil... 

Description The SUPERFLEX process is a proprietary technology patented by ARCO Chemical Technology, Inc. (now LyondellBasell) and exclusively offered worldwide for license by KBR. It uses a fluidized catalytic reactor system with a proprietary catalyst to convert low-value feedstocks to predominantly propylene and ethylene products. The catalyst is very robust thus, no feed pretreatment is required for typical contaminants such as sulfur, water, oxygenates or nitrogen. Attractive feedstocks include C4 and C5 olefin-rich streams from ethylene plants, FCC naphthas or C4S, thermally cracked naphthas from visbreakers or cokers, BTX or MTBE raffinates, olefin-rich streams removed from motor gasolines, and Fischer-Tropsch light liquids. 

Description The most predominant feed used to produce ethylene today is naphtha, as more than half of the world s ethylene is currently derived from cracking naphtha feed. The Advanced Catalytic Olefins (ACO) process is an alternative process that catalytically converts naphtha feed and is thus able to produce higher ultimate yields of light olefins (propylene plus ethylene) and at a higher P/E production ratio relative to steam cracking, typically about 1 1. 

Steam cracking (or middle temperature pyrolysis ) converts alkanes and refinery cuts [e.g., ethane, light fuels (naphtha)] into a mixture of saturated and unsaturated hydrocarbons, with ethylene, propylene, butenes, butadiene, benzene, and toluene being the most valuable products. 

We consider in the following a world-scale steam cracker plant with a production capacity of 125th ethene (Figure 6.6.8). The plant runs on light-run naphtha that is heated in the convection zone of the crack oven to 600 °C. The naphtha is mixed with water vapor (4.5 MPa, 257.5°C) to realize a steam-to-naphtha ratio of 0.45. This mixture is introduced to the main crack oven, which is an 80m tubular reactor at 850°C. The residence time of the feedstock in this hot section of the crack oven is 0.5 s. Following the crack oven, the product mixture is quenched to 200°C. In a first distillation column light components (C1-C5) are separated from the heavier pyrolysis products (Cs+). 

Properly speaking, steam cracking is not a refining process. A key petrochemical process, it has the purpose of producing ethylene, propylene, butadiene, butenes and aromatics (BTX) mainly from light fractions of crude oil (LPG, naphthas), but also from heavy fractions hydrotreated or not (paraffinic vacuum distillates, residue from hydrocracking HOC). 

The feedstocks used ia the production of petroleum resias are obtaiaed mainly from the low pressure vapor-phase cracking (steam cracking) and subsequent fractionation of petroleum distillates ranging from light naphthas to gas oil fractions, which typically boil ia the 20—450°C range (16). Obtaiaed from this process are feedstreams composed of atiphatic, aromatic, and cycloatiphatic olefins and diolefins, which are subsequently polymerized to yield resias of various compositioas and physical properties. Typically, feedstocks are divided iato atiphatic, cycloatiphatic, and aromatic streams. Table 2 illustrates the predominant olefinic hydrocarbons obtained from steam cracking processes for petroleum resia synthesis (18). 

Significant products from a typical steam cracker are ethylene, propylene, butadiene, and pyrolysis gasoline. Typical wt % yields for butylenes from a steam cracker for different feedstocks are ethane, 0.3 propane, 1.2 50% ethane/50% propane mixture, 0.8 butane, 2.8 hill-range naphtha, 7.3 light gas oil, 4.3. A typical steam cracking plant cracks a mixture of feedstocks that results in butylenes yields of about 1% to 4%. These yields can be increased by almost 50% if cracking severity is lowered to maximize propylene production instead of ethylene. 

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