摘要:

AbstractUsing four hazardous dispersion models, the ability to predict Lower Flammability Distance (LFD), the distance from a release through which the released gas is present in concentration below flammable range, has been evaluated using a set of large‐scale propane release field experiment data. The four models evaluated were the DEGADIS model, the SLAB model, the OME Simple Gas model and the OME Heavy Gas model (1983). The observed LFDs were compared with the predicted LFDs for three atmospheric conditions. The complete data set was broken into two parts: (1) the cyclone type releases (representing instantaneous release situations) and (2) the nozzle type releases (representing horizontal jet releases). A procedure based on the USEPA guidelines on air quality models was followed to evaluate the models.The complex models (DEGADIS and SLAB models) appear unreasonably weak in predicting LFD's compared with the relatively simple Gaussian model used in the OME Simple Gas model for instantaneous releases. The OME simple gas model is significantly better than the DEGADIS and SLAB models for cyclone type (instantaneous) releases under unstable and neutral atmospheric conditions; and the DEGASIS model is significantly better than the SLAB model for nozzle type (horizontal jet) releases under stable atmospheric conditions. Since the size of the data set is not large enough (n = 20 for cyclone type release and n = 18 for nozzle type release), it is difficult to show 95% significant differences between model

ISSN:1066-8527    

DOI:10.1002/prs.680120103

出版商:American Institute of Chemical Engineers    

年代:1993

数据来源: WILEY

ISSN:1066-8527    

DOI:10.1002/prs.680120102

出版商:American Institute of Chemical Engineers    

年代:1993

数据来源: WILEY

摘要:

AbstractSince publishing a listing of vapor cloud explosion incidents in 1977 and 1983, Industrial Risk Insurers has maintained an active database on these incidents. This second update gives the available data and reference sources on all known incidents.Modeling of blast effects of vapor cloud explosions has evolved in recent years. The multi‐energy method is very promising but presently only models quiescent clouds. Losses show that quiescent dispersion of clouds is not always realistic. Explosively dispersed clouds or violent dispersion of clouds have occurred recently. Very powerful explosions have resulted.As an insurance company trying to evaluate worst case scenarios, it is essential that research focuses on the modeling of explosively dispersed clouds or very turbulent clouds. The applicability of the multi‐energy method or the development of new methods for turbulent clouds should be investiga

ISSN:1066-8527    

DOI:10.1002/prs.680120104

出版商:American Institute of Chemical Engineers    

年代:1993

数据来源: WILEY

摘要:

AbstractKey elements of the testing requirements for new chemical substances under the various chemical control laws throughout the industrialized world are reviewed. Important issues in all of the systems are described. The influence of the Organization for Economic Cooperation and Development (OECD) is discussed. Similarities and differences in the testing requirements are outlined leading to a suggested strategy for introduction of new chemicals in the international markets.

ISSN:1066-8527    

DOI:10.1002/prs.680120105

出版商:American Institute of Chemical Engineers    

年代:1993

数据来源: WILEY

摘要:

AbstractAn experimental investigation has been performed into the venting of methane‐air explosions in heating plants. The investigation was performed on a realistic scale in a 38.5 m3enclosure. The first part of the experimental program concerns the influence of the “usual” parameters such as the vent opening area, the vent opening pressure, the ignition location and the vent opening configuration. The second part of the investigation concerns the influence of factors related to heating plants. Thus the effect of introducing a large obstacle, that is the central heating apparatus, and the effect of venting through a dormer window (heating plants are often located in the cellar of a building allowing explosion venting via a dormer window only) are investi

ISSN:1066-8527    

DOI:10.1002/prs.680120106

出版商:American Institute of Chemical Engineers    

年代:1993

数据来源: WILEY

摘要:

AbstractVinyl acetate monomer and acrylic acid and its esters are stabilized with phenolic polymerization inhibitors. Oxygen is needed for these stabilizers to work effectively in acrylic monomers, but is not necessary for vinyl acetate monomer, and actually destabilizes it at elevated temperatures.

ISSN:1066-8527    

DOI:10.1002/prs.680120107

出版商:American Institute of Chemical Engineers    

年代:1993

数据来源: WILEY

摘要:

AbstractAn unusual type of oscillatory, thermal instability in a reaction which takes place in a semi‐batch reactor, (i.e., when one reactant is admitted slowly to the reaction vessel and mixes with another reactant already present in the system) is investigated experimentally and theoretically. We show not only that oscillatory temperature changes may occur that are sufficiently large to constitute a formidable explosion hazard but also that the conditions under which such a hazard may take place could be entered unwittingly, in a mistaken belief that a move away from a potentially hazardous zone is being made. The theoretical background is formulated analytically in the context of a first order exothermic reaction. However, from the experimental study of the exothermic gaseous reaction between hydrogen and chlorine, we confirm the existence of oscillations and we show that the main features predicted by the simple theory transpose to more complex kinetic systems. In this particular system, temperature changes in excess of 200 K were measured in the unstable oscillatory region. The experimental study is linked to the theoretical foundations through numerical modelling of the non‐isothermal process, based on a detailed kinetic mechanism of the H2+ Cl2reaction. Similar oscillatory phenomena are also shown by numerical simulation to be possible in a semi‐batch reactor in an exothermic reaction between two li

ISSN:1066-8527    

DOI:10.1002/prs.680120108

出版商:American Institute of Chemical Engineers    

年代:1993

数据来源: WILEY

摘要:

AbstractA summary is presented of the chemical reactivity evaluation aspects of the soon to be published “Guidelines for Chemical Reactivity Evaluation and Application to Process Design” developed under the sponsorship of the Center for Chemical Process Safety. Emphasis is placed on strategies for thermochemical evaluation of industrial chemical substances.Certain structural entities, for example, high degrees of unsaturation and nitrogenhalogen linkages, will likely identify hazardous reactive chemicals. The effects of impurities in the chemicals, as well as, for example, incidental contact with water and air (oxygen), must also be considered in the evluation of potential reactivity hazards, representing undesired reactions.Various test methods are indicated briefly along with the rationale for use of specific methods in hazard evaluat

ISSN:1066-8527    

DOI:10.1002/prs.680120109

出版商:American Institute of Chemical Engineers    

年代:1993

数据来源: WILEY

摘要:

AbstractIn the framework of the evaluation of the three‐dimensional, finite volume code ADREAHF, a computational simulation of the Thorney Island Dense Gas Trial No. 8 is performed. A one‐equation turbulence closure scheme is adopted in this first approach. The results of the simulation are compared with the experimental data in the form of concentration‐time histories. The model predictions are satisfactory, with a tendency of the model to underestimate the maximum gas concentration and the time of its occurrence. The differences between model predictions and experimental data can be reduced by taking into account concentration fluctuations, utilization of finer numerical grids and improvements of the turbulence mode

ISSN:1066-8527    

DOI:10.1002/prs.680120110

出版商:American Institute of Chemical Engineers    

年代:1993

数据来源: WILEY

ISSN:1066-8527    

DOI:10.1002/prs.680120101

出版商:American Institute of Chemical Engineers    

年代:1993

数据来源: WILEY