ISSN:0278-4491    

DOI:10.1002/ep.670150402

出版商:American Institute of Chemical Engineers    

年代:1996

数据来源: WILEY

ISSN:0278-4491    

DOI:10.1002/ep.670150403

出版商:American Institute of Chemical Engineers    

年代:1996

数据来源: WILEY

ISSN:0278-4491    

DOI:10.1002/ep.670150404

出版商:American Institute of Chemical Engineers    

年代:1996

数据来源: WILEY

ISSN:0278-4491    

DOI:10.1002/ep.670150405

出版商:American Institute of Chemical Engineers    

年代:1996

数据来源: WILEY

ISSN:0278-4491    

DOI:10.1002/ep.670150406

出版商:American Institute of Chemical Engineers    

年代:1996

数据来源: WILEY

ISSN:0278-4491    

DOI:10.1002/ep.670150408

出版商:American Institute of Chemical Engineers    

年代:1996

数据来源: WILEY

ISSN:0278-4491    

DOI:10.1002/ep.670150409

出版商:American Institute of Chemical Engineers    

年代:1996

数据来源: WILEY

摘要:

AbstractLife Cycle Assessment (LCA) is an environmental auditing tool that quantifies the environmental burdens of an activity inclusive of all its related systems. In the past, LCA has been applied primarily to products, but recent literature suggests it also has potential as an analysis and design tool for processes and services. This potential arises from the unique ability of LCA to link the environmental burdens of a process with its mass and energy flows. The aim of this work is to apply LCA as a tool for process design rather than one for product assessment. A nitric acid plant formed the basis for a case study wherein LCA was used to quantify and compare environmental performance of a number of design alternatives aimed at waste reduction. Economic models for the alternatives were formulated and linked to the environmental models to perform a multiobjective optimization with the express aim to maximize economic returns and minimize enviromental impact. The comparative study showed that one design alternative was clearly superior from an environmental point of view. The optimization demonstrated that operational changes could result in significant enviromental improvement at minimal economic cost. Future work in this area should focus on the allocation of environmental burdens from multiple‐output processes as well as extending the analysis to include environmental and economic impacts of all related downstream processe

ISSN:0278-4491    

DOI:10.1002/ep.670150410

出版商:American Institute of Chemical Engineers    

年代:1996

数据来源: WILEY

摘要:

AbstractSimple laboratory experiments simulating a spill of a volatile liquid on sands were conducted. Hexane was spilled onto both initially dry sand and water‐wetted sand at near field capacity. The experimental conditions approximated the assumptions of a theory developed by Thibodeaux (1979). Predictions of a modification of this model were generally in good agreement at early times with data on the rate of volatilization. The modified model can be used to estimate air emissions of a volatile liquid spilled on sand

ISSN:0278-4491    

DOI:10.1002/ep.670150411

出版商:American Institute of Chemical Engineers    

年代:1996

数据来源: WILEY

摘要:

AbstractCurrently, hydrogen sulfide is removed from process gas streams by a series of reactions at high temperature to produce elemental sulfur in Claus, Stretford or other processes. These physicochemical processes have high intrinsic capital and operating costs, often are restricted by contaminants, and do not effectively remove all the H2S. As an alternative, the anaerobic, photosynthetic bacterium, Chlorobium thiosulfatophilum, has been demonstrated to convert hydrogen sulfide to elemental sulfur in a single step at atmospheric conditions. The autotrophic bacterium uses CO2as the carbon source. Energy for cell metabolism is provided by incandescent light and the oxidation of H2S. A bench scale study has been performed in a CSTR equipped with a sulfur separator. Optimum process conditions have been achieved to maximize cell growth and elemental sulfur production. Near total conversion of H2S is achieved in a retention time of a few minutes. High concentrations of H2S or organics do not affect the culture. Sulfur recovery by settling is very efficient and near theoretical yields of sulfur are achieved. Economic projections indicate that sour gas can be desulfurized for $ 0.08‐0.12/MSC

ISSN:0278-4491    

DOI:10.1002/ep.670150412

出版商:American Institute of Chemical Engineers    

年代:1996

数据来源: WILEY