摘要:

AbstractOSHA's regulation 1910.119, Process Safety Management of Highly Hazardous Chemicals, is having a significant impact on the affected industries. It's probably an understatement to say that industry has struggled to implement process safety management systems to comply with the regulation.

ISSN:1066-8527    

DOI:10.1002/prs.680120402

出版商:American Institute of Chemical Engineers    

年代:1993

数据来源: WILEY

摘要:

AbstractOn August 3, 1991, at about 12:20 pm, a deflagration occurred inside a wastewater treatment tank at the Allied‐Signal Delaware Plant. The tank was being used to hold treated wastewater prior to discharge to the plant process sewer system. One minor injury occurred as a result of the deflagration. The tank sustained damage to its manway, conservation assembly, and inlet and discharge piping. The building in which the tank was located had to have relief panels and roofing replaced and required repairs to the walls where the roof girders separated from the masonry.The exact cause of the deflagration is not known. Investigation of the incident indicated that the source of the deflagration was ignition of flammable vapors in the head space of the tank. The three most likely sources of ignition each involved the presence and use of hydrogen peroxide in the proces

ISSN:1066-8527    

DOI:10.1002/prs.680120403

出版商:American Institute of Chemical Engineers    

年代:1993

数据来源: WILEY

摘要:

AbstractThere have been instances where ignitions have occurred in oxygen enriched atmospheres in closed systems. The causes of these ignitions have been difficult if not impossible to explain by ordinary mechanisms, and even though electrostatics has been implicated, there have been no definitive mechanisms proposed which can explain the ignitions. This paper will perhaps be a step toward a satisfactory explanation by bringing another electrostatic mechanism to the attention of the loss prevention community.In an example incident, ignition occurred when oxygen was bubbling to the surface of a liquid where flammable vapors existed. It is known that bubbles breaking at a liquid surface can create an electic field in the atmosphere above the liquid. Also, in real systems, there are all sorts of surface discontinuities and things floating about so that there are sharp points where it is conceivable that corona discharge may develop, depending on the strength of the electrostatic field. In ordinary atmospheres, corona discharge is only incendive to very sensitive vapors and is considered to be non‐incendive to ordinary vapors, but on the other hand, it is well known that the minimum ignition energy requirements for ordinary vapors in pure oxygen atmospheres are some 100 times less than those in normal atmospheres. Such a reduction in energy requirements could likewise be expected for corona discharge. One can then speculate that such a self induced corona discharge could have been capable of igniting the flammable vapors which were in an oxygen enriched atmosphere. The experimental and theoretical pros and cons of this mechanism are discussed in the paper with no definitive conclusion being reache

ISSN:1066-8527    

DOI:10.1002/prs.680120404

出版商:American Institute of Chemical Engineers    

年代:1993

数据来源: WILEY

摘要:

AbstractImagine that a seemingly minor fire has been discovered in the warehouse storing raw materials for your plant. The fire department is notified and you expect that the emergency will be over shortly. Twelve hours and several millions dollars worth of damage later, the fire is extinguished. You stand there in shock as you try to make sense of what happened. Reality or fiction? The answer can depend on many factors, some of which you can resolve, easily, and some which will require an extensive commitment of time and money.

ISSN:1066-8527    

DOI:10.1002/prs.680120405

出版商:American Institute of Chemical Engineers    

年代:1993

数据来源: WILEY

摘要:

AbstractLarge segments of society no longer trust firms or government in regard to pronouncements on what is safe. Because of this distrust, particularly in regard to the chemical industry, the public has questioned many firms right to operate in their community and demanded and obtained increased rights for individuals to intervene directly in decisions by firms that might affect them.Chemical firms must establish or restore their credibility and social legitimacy in order to maintain their social franchise to operate. At a minimum, this requires an understanding how the firm's stakeholders view the firm's imposition of risks on them and their families and the engagement of these stakeholders in discussions about the firm's products and operations and the risks attendant on its presence in the community. Some chemical firms have formed community advisory councils as a way of accomplishing this rapproachement. However, they have found that a community council may have its own agenda, forcing the firm to provide information and deal with issues it would have preferred to avoid.

ISSN:1066-8527    

DOI:10.1002/prs.680120406

出版商:American Institute of Chemical Engineers    

年代:1993

数据来源: WILEY

摘要:

AbstractThe majority of buildings located at petrochemical plants, exclusive of control rooms, are of conventional construction and do not explicitly provide for resistance to blast loads. Typical construction types include steel frame with metal cladding, concrete masonry unit, and brick clad with concrete or steel frame. These buildings are designed for conventional loads without regard for high overpressures and fragments resulting from an accidental explosion. Current regulatory trends are causing many companies to evaluate design standards for new and existing support structures especially in the wake of recent accidental explosions. Response criteria is an important part of these design standards especially when they are used to analyze existing structures for blast protection. Structural evaluations at several sites have revealed that few existing structures meet current design criteria primarily due to weak member connections. Previous work has shown that many conventional structures can develop a surprising degree of resistance to blast loading if proper detailing is used in design, thus allowing members to develop their full capacity. This paper discusses response criteria currently used for new structures and examines the problem of determining acceptance criteria for existing structures. Data from explosion accidents and test programs is reviewed to determine the degree of conservatism in current criteria. Finally, alternatives for establishing blast capacity of existing structures are discussed.

ISSN:1066-8527    

DOI:10.1002/prs.680120407

出版商:American Institute of Chemical Engineers    

年代:1993

数据来源: WILEY

摘要:

AbstractThe experimental and theoretical research on vapor cloud explosions, performed at TNO Prins Maurits Laboratory, is discussed within the framework of the simple model for explosion blast prediction, the Multi‐Energy Method. This research is focused on the influence of obstacles and confinement present in the vapor cloud on flame acceleration and overpressure production. This led to the development of the CFD code for reactive mixtures REAGAS3D. The research is mainly performed within multi‐sponsor projects and is carried out in collaboration with other laboratories from various European countries.Further, the effect of vapor cloud explosions on constructions are discussed. The 3Dcode ABAQUS is used to quantify these effe

ISSN:1066-8527    

DOI:10.1002/prs.680120408

出版商:American Institute of Chemical Engineers    

年代:1993

数据来源: WILEY

摘要:

AbstractIn general, rupture discs are designed to give a virtually instantaneous pressure relief opening to a relief system at a predetermined pressure. For safe design of pressure relief systems, consideration must be given to the sizing and the specification of the rupture disc but also to the reaction forces that result when a gas is discharged. These reaction forces can be excessive in the case of venting at high pressures.When a disc ruptures, a shock wave propagates through the gas in the piping behind the rupture disc. This exerts a transient reaction force on the pressure relief system. In the case of steady supersonic flow choking often occurs at one or more points in the pressure relief line and a shock is formed in the pipe. The pressure in the relief line may increase considerably during blowdown as a result of choking at the end of the pipe. Depress‐surization experiments were conducted with nitrogen at high pressures.The results of the pressure measurements in the piping during blowdown are compared with exploratory calculations. The reaction forces exerted on a pressure relief system can be assessed from the pressures and the mass flow rate of the gas as a function of time. For safe design of pressure relief systems, both steady‐state flow reaction forces and the initial transient forces should be conside

ISSN:1066-8527    

DOI:10.1002/prs.680120409

出版商:American Institute of Chemical Engineers    

年代:1993

数据来源: WILEY

摘要:

AbstractFIBC use is increasing rapidly owing principally to improved handling efficiency and product quality improvement. However, selection of the proper FIBC has many aspects, of which safety is paramount. Numerous accidents have occurred when emptying flammable powders from FIBCs, both with and without flammable vapors additionally present. Owing to the mode of operation and speed of emptying, not only is there a high probability of static generation but also a high probability of one or more operators being in the flash fire zone should ignition occur. Apart from the flash fire produced by a dust cloud and/or flammable vapors displaced from a receiving vessel, a flame may in some cases propagate into the FIBC, which might then explode. This paper discusses the FIBC selection problem, a series of case histories, and available literature. Since no FIBC loading incidents are known, the paper will focus on emptying. In particular it should be appeciated that the potential for operator grounding error and sudden nemesis can be very high.

ISSN:1066-8527    

DOI:10.1002/prs.680120410

出版商:American Institute of Chemical Engineers    

年代:1993

数据来源: WILEY

ISSN:1066-8527    

DOI:10.1002/prs.680120401

出版商:American Institute of Chemical Engineers    

年代:1993

数据来源: WILEY