Venting requirements

Knox, A. C., Venting Requirements for Deaerating Fleaters, Chemical Engineering, January 23, 1984. 

These systems are ealled tempering (i.e., to prevent temperature rise after venting) systems beeause there is suffieient latent heat available to remove the heat of reaetion and to temper the reaetion at the set pressure. The vent requirements for sueh systems are estimated from the Leung s Method [31,32] ... 

Fluff, J., Emergeney Venting Requirements, Plant/Operations Progress, 1 (4), pp. 211-219, 1982. 

For tank design per API Standard 650 with weak roof to shell designs (roof lifts up) the venting requirements of API-Std-2000 do not apply for emergency venting to atmosphere or elsewhere. 

Thermal outbreathing or venting requirements, including thermal evaporation for a fluid (the code refers to oil) with a flash point of 100°F or below, use at least the figures of Column 4 in Table 7-14. 

Thermal outbreathing or venting requirements, including thermal evaporation for a fluid (the code... 

Using Table 7-14, for 26,000 gallon capacity, required vent = 371 SCFH free air at 14.7 psia and 60°F. Interpolating, vent required for 26,000 gallon capacity. 

Total Rate of Emergency Venting Required for Fire Ebcposure Vs. Wetted Surface Area (wetted area vs. ft. of free air/hr, 14.7 psia, 60°F)... 

Wetted Area" (square feet) Venting Requirement (cubic feet of free air " per hour) Wetted Area" (square feet) Venting Requirement (cubic feet of free air per hour)... 

The code [26] allows a credit or reduction of required emergency venting for specific conditions. The final total emergency venting requirements may be determined as ... 

For refrigerated tanks the total venting requirement is the value determined from Table 7-17, multiplied by the environment factor F from Table 7-18. For tanks greater than 2,800 ft. exposed wetted surface, use the venting formula for V,. (Equation 7-49). Do not apply the factors from Table 7-18. 

Huff, J. E., Emergency Venting Requirements, Planl/Oper-alions Progress, 1 (4), 211-229, October 1982. 

Vc = cubic feet of free air per hour from Table 7-17, which is 14.7 psia and 60°F, or from Equation 7-49, for wetted area A,v > 2800 sq ft V = venting requirement, cubic feet free air per hour at 14.7 psia and 60°F... 

Another feature of the VSP is the ability to differentiate between foamy and nonfoamy behavior of the system under investigation, which is especially important in considering venting requirements. The following types of foaming systems are recognized ... 

Worst-case analysis based on the DSC data, namely, the test with the lowest onset temperature, resulted in a graph showing the relationship between initial temperature and time-to-maximum rate under adiabatic conditions. For an initial temperature of 170°C, it would take 2 hours to reach the maximum rate. Venting simulation tests were undertaken on a larger scale to detect safe venting requirements for the separator and for the MNB hold tank. Several vent sizes were tested. It was found that a 10-cm rupture disc with a burst pressure 1 bar above the operating pressure was adequate. 

De Haven, E. S., "Approximate Hazard Ratings and Venting Requirements from CSI-ARC Data", Plant/Operations Progress, 2, No. 1 (1983). 

Advanced Reactive System Screening Tool (ARSST ) The ARSST measures sample temperature and pressure within a sample containment vessel. The ARSST determines the potential for runaway reactions and measures the rate of temperature and pressure rise (for gassy reactions) to allow determinations of the energy and gas release rates. This information can be combined with simplified methods to assess reactor safety system relief vent requirements. 

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