Equipment damage

Explosively violent hydrolysis can occur if an excess of a strong acid (H2SO4, HNO, or HCl) is added to hydrogen cyanide. The reaction is fastest at or near stoichiometric ratios, eg, 1 to 2 moles H2SO4 per mole HCN, and can cause severe equipment damage if confined. 

Process Safety Considerations. Unit optimization studies combined with dynamic simulations of the process may identify operating conditions that are unsafe regarding fire safety, equipment damage potential, and operating sensitivity. Several instances of fires and deflagrations in ethylene oxide production units have been reported in the past (160). These incidents have occurred in both the reaction cycle and ethylene oxide refining areas. Therefore, ethylene oxide units should always be designed to prevent the formation of explosive gas mixtures. 

Cavitation Loosely regarded as related to water hammer and hydrauhc transients because it may cause similar vibration and equipment damage, cavitation is the phenomenon of collapse of vapor bubbles in flowing liquid. These bubbles may be formed anywhere the local liquid pressure drops below the vapor pressure, or they may be injected into the hquid, as when steam is sparged into water. Local low-pressure zones may be produced by local velocity increases (in accordance with the Bernouhi equation see the preceding Conservation Equations subsection) as in eddies or vortices, or near bound-aiy contours by rapid vibration of a boundaiy by separation of liquid during water hammer or by an overaU reduction in static pressure, as due to pressure drop in the suction line of a pump. 

Hazards that could re.sult in major equipment damage and consequently lengthy plant downtime. No redundancy is normally required for these, although redundancy is always an option. Situations that result in minor equipment damage that can be quickly repaired do not generally require a safety interlock however, a process interlock might be appropriate. 

Practical separation techniques for hquid particles in gases are discussed. Since gas-borne particulates include both hquid and sohd particles, many devices used for dry-dust collection (discussed in Sec. 17 under Gas-Sohds Separation ) can be adapted to liquid-particle separation. Also, the basic subject of particle mechanics is covered in Sec. 6. Separation of liquid particulates is frequently desirable in chemical processes such as in countercurrent-stage contacting because hquid entrainment with the gas partially reduces true countercurrency. Separation before entering another process step may be needed to prevent corrosion, to prevent yield loss, or to prevent equipment damage or malfunc tion. Separation before the atmospheric release of gases may be necessaiy to prevent environmental problems and for regula-toiy compliance. 

The accident reporting procedure should be more than reporting of equipment damage for insurance purposes. The report should show appropriate action taken to prevent a recurrence. 

Don t start the pump until after completing all the previously mentioned points, and any other specification mentioned in the operation and maintenance manual of the pump provided by the pump supplier. Not doing this could cause equipment damage and even personal injury. It might even void the pump guarantee. 

Using fire models, locations of equipment, heat transfer calculations, and environmental qualifications of the equipment, it is possible to estimate the time to failure. Fragility cuives that relate fire durations and equipment damage while considering the probability of fire suppre.ssion are produced to relate to the overall PSA. These fragility curves and their use is simitar the methods ised for seismic analysis. 

In June 1972, at Quad Cities Unit 1, a rupture in the circulating-water system caused the rapid flooding of a room containing a number of pumps for different systems. The equipment damaged... 

Three years ago, a fire in a large mining operation resulted in tens of millions of dollars in equipment damage and a half-billion dollar loss from months of lost production. 

Satisafactory compressor installations many times depend on how well the foundation or support structure was designed. An inadequate foundation design can result in equipment damage due to excessive vibration. The money saved by cutting comers on foundation design effort may be spent many times in costs associated with high maintenance and lost production. 

Checks of critical process parameters and warnings about hazardous conditions that can cause injury or equipment damage are important factors which determine the occurrence and recovery of human error. The purpose of these checks is to emphasize critical process information. Because of the critical nature of this information, checks and warning should be highlighted in a way that distinguishes them from other notes, and should be located where process workers will not overlook them. 

The records display a pattern of maintenance and repair that is rarely visible elsewhere and can show less severe equipment damage trends that can lead to total failure. As such, it is possible to determine the total number of failures and failure severity. 

The potential for knock-on effects resulting from equipment damage should be considered. 

Prudent design requires that equipment be protected from credible underpressurization scenarios. Equipment damage can result when such protections are omitted, improperly sized, incorrectly designed or installed, or inadequately maintained. Common failures include the following. 

Failures can either be fail-safe or fail dangerously. Fail safe incidents may be initiated by spurious trips that may result in accidental shutdown of equipment or processes. Fail dangerously incidents are initiated by undetected process design errors or operations, which disable the safety interlock. The fail dangerously activation may also result in accidental process liquid or gas releases, equipment damage, or fire and explosions. 

In addition to causing injuries and fatalities to plant personnel and the public, reactive incidents can also result in environmental harm and equipment damage. These impacts may be due to fires, explosions, hazardous liquid spills, toxic gas releases, or any combination of such (Figure 6). Fires and explosions are the most frequent occurrence in CSB data, followed by toxic gas releases. 

In the liquid-to-vapor phase change, the key element is time. If significant vaporization occurs in a short time period, the process can, and usually does, resemble an explosion. If the liquid quantities are not small, concomitant shock waves emanating from the site of vapor formation may result in personnel injury or equipment damage. 

MINOR 3 SAFETY - Single injury, not severe, possible tost time. OPERABILITY - Some equipment damage ( 10Qk to 1MM) with possible downtime. ENVIRONMENTAL 6 CCMMUNITY IMPACT Odor or noise complaint From the public. Releese Ihat results in some Agency notification or viciatior. 1 3 4 5... 

INCIDENTAL 4 SAFETY Minor Injury or no Injury. OPERABILITY - Minimal equipment damage less than SIOOK) with negligible plani downtime. ENVIRONMENT COMMUNITY IMPACT No impact off sl e. Erytronmental recordable event with no agency notification. A 5 5 S... 

An early warning HSSD smoke detection system can be used to detect incipient stage fires and allow manual intervention prior to significant equipment damage. Hence, fire suppression may not be required. 

Although the stoichiometry for reaction (9.1) suggests that one only needs 1 mol of water per mole of methane, excess steam must be used to favor the chemical equilibrium and reduce the formation of coke. Steam-to-carbon ratios of 2.5-3 are typical for natural gas feed. Carbon and soot formation in the combustion zone is an undesired reaction which leads to coke deposition on downstream tubes, causing equipment damage, pressure losses and heat transfer problems [21]. 

If there was no injury, death, equipment loss, or equipment damage, complete form 101. 

A firefighter is filling out fire reports on a fire in which there was one death, no equipment damage or loss, and one injury in addition to the death. Which forms must the firefighter complete ... 

---