Liquid handling properties

Important liquid fuel properties for a gas turbine are shown in Table 12-5. The flash point is the temperature at which vapors begin combustion. The flash point is the maximum temperature at which a fuel can be handled safely. 

Anticipated process variations that may affect the sizing of the driver (such as changes in pressure, temperature, or properties of the liquid handled, as well as special plant start-up conditions) will be specified. 

Liquid products contain sulfur and nitrogen and must be hydroprocessed to improve quality. Separate hydroprocessing units for upgrading the naphtha, kerosene, and gas oil fractions can be used to optimize the overall process. Refined gas oil or diesel fuel is aromatic in character and contains more cycloparaffins than conventional crude oil. The resulting fuel is low in cetane number, high in density, and typically has very good low-temperature handling properties. 

The handling properties of the formulation in the field. Examples of handling properties are the amount of dust in the product (in the case of dry formulations), the manner in which the product dilutes with water (or other carrier liquid), the way in which the product sprays through an agricultural spraying system, and the manner in which the product will tank mix with other pesticide formulations. This paper is addressed to this last concern. 

The feed type is a very basic description particulate can also include powders, granules, pastes, pellets, performs, etc. liquid/slurry also includes solutions and sludges. Table 12-12 gives a more comprehensive classification based on particle size and handling properties. 

There are usually many candidate solvents for any particular application. Important factors to consider are (1) the affinity of the solute for the solvent (i.e., its distribution coefficient should be large) (2) the affinity of other species in the mixture for the solvent (i.e., their distribution coefficients should be small) (3) solvent safety considerations (e.g., flammability and toxicity) (4) solvent handling properties such as density, viscosity, and vapor pressure (5) solvent solubility in the raffinate phase (high solubilities may translate into high solvent losses unless steps are taken to prevent such losses) and (6) solvent cost. In addition, liquid-liquid interfacial tension affects the interfacial area and the rate of mass transfer between the phases. 

As shown in the previous section, the diameter of a packed absorption tower depends on the quantities of gas and liquid handled, their properties, and the ratio of one stream to the other. The height of the tower, and hence the total volume of packing, depends on the magnitude of the desired concentration changes and on the rate of mass transfer per unit of packed volume. Calculations of the tower height, therefore, rest on material balances, enthalpy balances, and estimates of driving force and mass-transfer coefficients. 

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