Naphtha blends, properties

The majority of today s turbines arc fueled wth natural gas or No. 2 distillate oil. Recently there has been increased interest in the burning of nonstandard liquid fuel oils or applications where fuel treatment is desirable. Gas turbines have been engineered to accommodate a wide spectrum of fuels. Over the years, units have been equipped to burn liquid fuels, including naphtha various grades of distillate, crude oils, and residual oils and blended, coal-derived liquids. Many of these nonstandard fuels require special provisions. For example, light fuels like naphtha require modifications Co the fuel handling system to address high volatility and poor lubricity properties. 

A tank containing 1500 m3 of naphtha is to be blended with two other hydrocarbon streams to meet the specifications for gasoline. The final product must have a minimum research octane number (RON) of 95, a maximum Reid Vapor Pressure (RVP) of 0.6 bar, a maximum benzene content of 2% vol and maximum total aromatics of 25% vol. The properties and costs of the three streams are given in the Table 3.5. 

This article is an overview of the novel technology of self-reinforced LCPs with polyesters, poly(ethylene terephthalate) (PET) and poly(ethylene naphtha-late) (PEN) [10-13, 21, 23], LCP/polyester blends in a polyester matrix form in situ fibrils which improve the mechanical properties. LCPs have an inherently low melt viscosity, and provide LCP/polyester blends that effectively lower the melt viscosity during melt spinning [24], and fast injection-molding cycles. The miscibility between the LCP and polyesters can be controlled by the degree of transesterification [25] in the reactive extrusion step, and fibril formation in LCP-reinforced polyester fibers has been studied. 

The term white distillate is applied to all the refinery streams with a distillation range between approximately 80 and 360°C (175 to 680°F) at atmospheric pressure and with properties similar to the corresponding straight-run distillate from atmospheric crude distillation. Light distillate products (i.e., naphtha, kerosene, jet fuel, diesel fuel, and heating oil) are all manufactured by appropriate blending of white distillate streams. 

To specify charge stock characteristics, one of several options can be used specify a detailed gas chromatographic composition call the naphtha library estimate composition from general charge stock properties, such as PON A (% paraffins, olefins, naphthenes, and aromatics) and gravity or blend up to seven naphthas by utilizing the naphtha library. 

The model is user friendly and the input requirements are simple. An example of typical user input is shown in Table XIV, which contains all necessary information to run the model. In the example, charge stock information for a blend of two naphthas is produced by means of naphtha library codes the detailed composition developed by the module INPUT for the specified naphtha codes is shown in Table XV. Optional output of yields, temperature, and octane at six points through each reactor can also be generated. The process and reactor conditions are summarized in Table XVI, and complete yields along with the product properties are shown in Table XVII. 

Feeds. Properties of two hydrofined test feeds are given in Table I. The California gas oil blend was used in tests simulating a hydrocracking unit producing both naphthas and jet fuel, the Mid-Continent blend in tests representing a unit producing naphtha as the major product. 

H-Coal naphthas and distillates derived from Illinois No. 6 (Burning Star Mine) and Wyodak coals were supplied by Hydrocarbon Research, Inc. The naphthas and distillates were blended in the appropriate proportions to obtain a whole syncrude derived from each coal. Properties of these syncrudes are shown in Table I. For comparison, Table I also shows properties of the SRC-II syncrude used in the study described in the previous chapter. The SRC-II syncrude was derived from a West Virginia coal (Pittsburgh Seam, Blacksville No. 2 Mine of the consolidated Coal Company). The H-Coal and SRC-II syncrudes are not directly comparable because the coals used to derive these syncrudes differ. 

For all of the hydrocracker operations, the feed properties are those of the heavy naphtha from the base crude mix blended with a specified fraction of light cycle oil from the base FCC operation. For all of the motor reformer operations, the feed properties are those of the motor naphtha from the base crude mix blended with heavy hydrocrackate from the base hydrocracker operation. For all of the BTX reformer operations, the feed properties are those of the BTX naphtha from the base crude mix blended with light hydrocrackate from the base hydrocracker operation. Finally, for each process unit, the process simulator computes the change in plant performance associated with a fixed perturbation of each feed property about the base operation. 

Table V. Properties of Naphtha Fractions from Hydrotreated Shale Oil Blends and from Arabian Light Crude...

Chem. Descrip. Polyester resin (50%) modified with sag control agent (3.8-4.2%) in solvent naphtha 150/180/xylene Uses Polyester blending resin for solv.-borne base coats and top coats Features Used in combination with compat. resins improves sag control Properties Milky to wh. appearance < 15 m grinding fineness dens. = 1.01 g/cm (20 C) dynamic vise. 350-1200 mPa-s- acid no. < 10 flash... 

Chem. Descrip. Thermoset PU resin in solvent naphtha 150/DBE blend Uses Raw material for exterior architecture coatings, traffic coatings Properties Sol n. 60% solids... 

Chemically, OXSOL 2000 is alpha, alpha, alpha-trifluorotoluene, an HFC. OXSOL 2000 has a number of desirable properties for precision cleaning, electronics cleaning, aerosol applications, and wipe cleaning. It is a pure compound, with a relatively fast evaporation rate and toluene-like odor. In its pure form, OXSOL 2000 is a good replacement for hexane, toluene, and VM P naphtha where a rapid evaporation rate is desirable and a flammable solvent can be used safely. In addition, OXSOL 2000 can be blended with classical solvents like trichloroethylene yielding non-flammable, very fast evaporating compositions. 

Polyester fibers with improved properties are prepared from blends of PET with PEN, or a blend of PET with a copolymer having terephthalate and naphtha-late units [99]. In addition, recycled PET can be used, thus providing a valuable use for recycled polyester materials. 

The properties of the naphtha feedstock utilized in the experimental campaign are presented in Figure 2. The source of the feedstock was Kuwait crude. This naphtha feedstock was synthesized by blending 35 volume percent light Kuwait and 65 volume percent heavy Kuwait. This blend does not occur in the virgin crude and as such is somewhat heavier than the true virgin feed. The isoparaffins were about 60% of the total paraffins and the alkylcyclohexanes were about 60% of the naphthenes. 

Blending components used in the Auto/Oil Study were obtained from various streams from current refinery configurations. They include FCC gasolines, reformates, straight run naphtha, alkylates and isomerate. Table 3 shows the compositional analysis and physical properties of these blending stocks. 

PE bottles exhibit a very poor gasoline permeation resistance, where about 25% of the filled gasoline penetrates out of a PE bottle in 14 days at 40 °C. Xylene, white spirit, cleaning naphtha, and many other pure and/or mixed hydrocarbon solvents easily penetrate PE containers such permeation results in pollution, safety, and health problems. The laminar blends of PE and PA, polyvinyl alcohol, and/or EVOH (with 32% ethylene), in the presence of modified PA or zinc-neutralised ethylene-acrylic acid copolymer as compatibilisers, exhibit significantly higher barrier properties as compared with PE or the conventional homogeneous hlends associated with uniform dispersed PA within a PE matrix [11]. 

Example 22-4. Vapor Pressure of Blends. Naphtha and natural gasoline are to be blended. The properties of the stocks are... 

Chem. Descrip. Blend of alkanolamides and syndets Uses Dispersant, emulsifier for oil slicks, naphthas, kerosene, other soivs. general cleaning of crude oil, marine and land transport, and mfg. plants Properties Liq. sp.gr. 1.0173 vise. 706.3 SSU (37.8 C) pour pt. -9.4 C flash pt. 

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