Process Revamping of H2SO4 Plant to Double Contact Double Absorption (DCDA) Using ASPEN HYSYS to Reduce SO2 Emission: Case of Awash Melkassa Sulfuric Acid Factory

This work presents a theoretical investigation of the simulation of Sulfuric acid process plant. In the production of the acid in contact process liquid sulfur is sequentially oxidized to Sulfur tri oxide via an exothermic reaction which is absorbed by 98% Sulfuric acid in an absorption tower. In this research Aspen One V7.2 has been successfully used to design every sub-process of the sulfuric acid plant in one integrated environment. In order to simulate the process as accurately as possible COM thermo was selected as advanced thermodynamics. Electrolyte NRTL and Peng-Robinson were used for liquid and vapor phase respectively as fluid package and HYSYS properties were used for simulation. The simulation of sulfuric acid process included automatic chemistry generation and the capacity of handling electrolyte reactions for all unit models. Aspen-HYSYS provides specialized thermodynamics models and built-in data to represent the non-ideal behavior of liquid phase components in order to get accurate results. Material and energy flows, sized unit operations blocks can be used to conduct economic assessment of each process and optimize each of them for profit maximization. The simulation model developed can also be used as a guide for understanding the process and the economics, and also a starting point for more sophisticated models for plant designing and process equipment specifying. DOI: http://dx.doi.org/10.3329/jce.v26i1.10182 JCE 2011; 26(1): 47-49

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The influence of the catalyst worktime on SO2 emission quantity from the sulfuric acid system and the catalyst waste material

Polish Journal of Chemical Technology ◽

10.2478/v10026-007-0073-0 ◽

2007 ◽

Vol 9 (3) ◽

pp. 134-137 ◽

Cited By ~ 2

Author(s):

Piotr Grzesiak ◽

Marcin Grobela ◽

Rafał Motała

Keyword(s):

Sulfuric Acid ◽

Waste Material ◽

Catalytic Process ◽

Acid Formation ◽

Main Step ◽

Acid System ◽

So2 Emission

The influence of the catalyst worktime on SO2 emission quantity from the sulfuric acid system and the catalyst waste material The catalytic process of SO2 to SO3 oxidation is the main step of sulfuric (VI) acid formation. The sustained catalyst operating due to its structural and textural modifications could disturb the process course. This paper includes the influence of the vanadic catalyst worktime on SO2 emission and the expected amount of the obtained waste material of the inactivated catalyst.

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Preparation of Thin Cadmium Telluride Samples for Electron Microscope Studies

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100052754 ◽

1974 ◽

Vol 32 ◽

pp. 548-549

Author(s):

T. J. Magee ◽

J. Peng ◽

J. Bean

Keyword(s):

Electron Microscope ◽

Sulfuric Acid ◽

Solid State ◽

Sample Preparation ◽

Cadmium Telluride ◽

Potassium Dichromate ◽

Optical Components ◽

The Past ◽

Solid State Devices

Cadmium telluride has become increasingly important in a number of technological applications, particularly in the area of laser-optical components and solid state devices, Microstructural characterizations of the material have in the past been somewhat limited because of the lack of suitable sample preparation and thinning techniques. Utilizing a modified jet thinning apparatus and a potassium dichromate-sulfuric acid thinning solution, a procedure has now been developed for obtaining thin contamination-free samples for TEM examination.

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Physical, Chemical, and Crystallographic Characterization of Anodic Coatings on High Strength Aluminum Base Alloys

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100093146 ◽

1976 ◽

Vol 34 ◽

pp. 636-637

Author(s):

R. E. Herfert ◽

N. T. McDevitt

Keyword(s):

Sulfuric Acid ◽

Salt Spray ◽

High Strength ◽

Environmental Stability ◽

Anodic Films ◽

Sodium Dichromate ◽

Corrosion Resistant ◽

Aerospace Applications ◽

Bond Strengths ◽

Adhesive Bonded Joints

Durability of adhesive bonded joints in moisture and salt spray environments is essential to USAF aircraft. Structural bonding technology for aerospace applications has depended for many years on the preparation of aluminum surfaces by a sulfuric acid/sodium dichromate (FPL etch) treatment. Recently, specific thin film anodizing techniques, phosphoric acid, and chromic acid anodizing have been developed which not only provide good initial bond strengths but vastly improved environmental durability. These thin anodic films are in contrast to the commonly used thick anodic films such as the sulfuric acid or "hard" sulfuric acid anodic films which are highly corrosion resistant in themselves, but which do not provide good initial bond strengths, particularly in low temperature peel.The objective of this study was to determine the characteristics of anodic films on aluminum alloys that make them corrosion resistant. The chemical composition, physical morphology and structure, and mechanical properties of the thin oxide films were to be defined and correlated with the environmental stability of these surfaces in humidity and salt spray. It is anticipated that anodic film characteristics and corrosion resistance will vary with the anodizing processing conditions.

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