Ammonia liquid, vapor pressure

Liquid ammonia is stored in a tank at 24°C and a pressure of 1.4 X 106 Pa. A pipe of diameter 0.0945 m breaks off a short distance from the vessel (the tank), allowing the flashing ammonia to escape. The saturation vapor pressure of liquid ammonia at this temperature is 0.968 X 106 Pa, and its density is 603 kg/m3. Determine the mass flow rate through the leak. Equilibrium flashing conditions can be assumed. 

The first example was formulated by Stoecker to illustrate the steepest descent (gradient) direct search method. It is proposed to attach a vapor recondensation refrigeration system to lower the temperature, and consequently vapor pressure, of liquid ammonia stored in a steel pressure vessel, for this would permit thinner vessel walls. The tank cost saving must be traded off against the refrigeration and thermal insulation cost to find the temperature and insulation thickness minimizing the total annual cost. Stoecker showed the total cost to be the sum of insulation cost i = 400jc° 9 (x is the insulation thickness, in.), the vessel cost v = 1000 + 22(p — 14.7)1-2 (p is the absolute pressure, psia), and the recondensation cost r = 144(80 — t)/x (t is the temperature, °F). The pressure is related to the temperature by... 

White tetragonal or orthorhombic crystal density 1.17g/cm3 refractive index 1.74 unstable, sublimes readily at ordinary temperatures vapor pressure 748 torr at 32°C highly soluble in water, alcohol, liquid ammonia and liquid hydrogen sulfide insoluble in benzene, hexane and ether. 

Colorless cubic crystal density 6.33 g/cm melts at 1,110°C vaporizes at 1,748°C vapor pressure 5 torr at 1,231°C moderately soluble in water, 4.35 g/lOOmL at 25°C soluble in hydrofluoric and other mineral acids practically insoluble in alcohol and liquid ammonia. 

Golden yellow, soft and ductile metal body-centered cubic structure density 1.93 g/cm melts at 28.44°C vaporizes at 671°C vapor pressure 1 torr at 280°C electrical resistivity 36.6 microhm-cm (at 30°C) reacts with water dissolves in liquid ammonia forming a blue solution. 

Silvery metal body-centered cubic structure imparts crimson-red color to flame density 0.862g/cm3 at 20°C melts at 63.25°C density of hquid potassium at 100°C is 0.819 g/cm and 0.771g/cm3 at 300°C vaporizes at 760°C vapor pressure 123 torr at 587°C electrical resistivity 6.1 microhm-cm at 0°C and 15.31 microhm-cm at 100°C viscosity 0.25 centipoise at 250°C surface tension 86 dynes/cm at 100°C thermal neutron absorption cross section 2.07 barns reacts violently with water and acids reacts with alcohol dissolves in liquid ammonia and mercury... 

Gallium(III) bromide is a hygroscopic, white solid which sublimes readily and melts at 122.5° to a covalent, dimeric liquid. The solid is ionic and its electrical conductivity at the melting point is twenty-three times that of the liquid.5 The vapor pressure of the liquid at T°K is given by the equation log p(mm.) = 8.554 — 3129/T and the heat of dissociation of the dimer in the gas phase is 18.5 kcal./mol.3 At 125° the liquid has the following properties 5,6 density, 3.1076 dynamic viscosity, 2.780 c.p. surface tension, 34.8 dynes/cm. and specific conductivity, 7.2 X 10-7 ohm-1 cm.-1 Gallium(III) bromide readily hydrolyzes in water and forms addition compounds with ligands such as ammonia, pyridine, and phosphorus oxychloride. 

The liquid ammonia is stored in the tank at a temperature of 20°C under its vapor pressure of 851 kPa. Under these conditions the discharge calculations show that all of the ammonia in the vessel is released to the... 

You can easily block in liquid-full chemical process piping with no vapor space for expansion. Many fluids, including liquid ammonia, liquid chlorine, liquid propane, liquid vinyl chloride, and benzene, if improperly isolated, can develop hundreds of pounds per square inch (many atmospheres) of pressure with fluctuation in nighttime and daytime temperatures. The liquid tries to expand as a result of its physical properties, but it is prevented by... 

Anhydrous ammonia also is known to cause temporary platicization of wood. The ammonia swells and plasticizes both the lignin and the cellulose, and the crystalline structure of the cellulose is converted to a different form in the process. To shape the wood, it is immersed in liquid ammonia or treated with gaseous ammonia under pressure until the cell walls have been penetrated and the wood becomes pliable and flexible. In this condition it is easily shaped and formed by hand or mechanically. The ammonia readily vaporizes and evaporates from the wood, so that the wood regains its normal stiffness but retains the new form into which it has been shaped. With this process the wood can be distorted into quite complex shapes without springing back to its original form. Treating plants have been developed on a pilot-plant scale, but the process has not been widely adopted. 

The following, from [72], is a formula for interpolation along the vapor pressure curve for liquid ammonia (viscosity q in N s m 2) ... 

The formation of ammonium sulfate and ammonium nitrate aerosols is an acid-base reaction in the atmosphere. Ammonia neutralizes the acids. Sulfuric acid has a very low vapor pressure (< 10 atm) and thus exists in the atmosphere as liquid particles, which react with NH3 and H2O (reaction 22). 

Scrubber liquid can be recycled to obtain a salt solution of any desired concentration prior to regeneration of ammonia from the solution. The upper limit on solution concentration presumably will be controlled by the vapor pressures of the components, ammonia and sulfur dioxide. At high pH, ammonia vapor predominates at low pH, sulfur dioxide is the dominant vapor. Therefore, optimum recycle of the scrubber liquid will be controlled at low pH and dilute solution concentration concurrent with and relative to equipment (capital) and operating costs. A solution having low pH (e.g., < 6.0) requires stainless steel or protected carbon steel to prevent corrosion. 

The normal boiling point of liquid ammonia is 240 K the enthalpy of vaporization at that temperature is 23.4 kj mol . The heat capacity of gaseous ammonia at constant pressure is 38 J moC ... 

In its pure form, nitric acid is a liquid with a high vapor pressure (47.6 torr at 20° C), so that in the lower atmosphere, HNO3 exists as a gas, in an aerosol or in a cloud droplet. When nitric acid reacts with a base a nitrate salt is produced. If the atmospheric base is ammonia, NH4NO3 is the result ... 

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