Computing multi-species chemical equilibrium with an algorithm based on the reactionextents

| June 7, 2019

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A mathematical model for the solution of a set of chemical equilibrium equations in a multi-species and multiphase chemical system is described. The computer-aid solution of model is achieved by means of a Newton-Raphson method enhanced with a line-search scheme, which deals with the non-negative constrains. The residual function, representing the distance to the equilibrium, is defined from the chemical potential (or Gibbs energy) of the chemical system. Local minimums are potentially avoided by the prioritization of the aqueous reactions with respect to the heterogeneous reactions. The formation and release of gas bubbles is taken into account in the model, limiting the concentration of volatile aqueous species to a maximum value, given by the gas solubility constant. The reaction extents are used as state variables for the numerical method. As a result, the accepted solution satisfies the charge and mass balance equations and the model is fully compatible with general reactive transport models. Keywords: Chemical equilibrium, Speciation, Reaction extent, Reactive transport

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Clariant

Clariant is a globally leading specialty chemicals company, based in Muttenz near Basel/Switzerland. The company employs a total workforce of around 17 200. In the financial year 2015, Clariant recorded sales of CHF 5.807 billion for its continuing businesses. The company reports in four business areas: Care Chemicals, Catalysis & Energy, Natural Resources, and Plastics & Coatings. Clariant’s corporate strategy is based on five pillars: increase profitability, reposition portfolio, add value with sustainability, foster innovation and R&D, and intensify growth.

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CHEMICAL MANAGEMENT

Energy portfolio restructuring: Charting the future

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How Chemical Companies Benefit from the Experience Economy

Article | June 17, 2021

To feel or experience from a business engagement started with customer experience mainly in the consumer products business. Today it has extended to even knowledge industries like the chemical industry where experiencing or feeling can be leveraged to include all stake holders from customers primarily to employees to supply chain people & suppliers and all else. With digital technologies this has become easier than before. The benefits from promoting the ‘feel’ or ‘experience’ emotion could be multifarious for the chemical industry as described in this article.

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CHEMICAL TECHNOLOGY

Survey Report: The State of Intelligent Operations in Oil and Gas

Article | June 17, 2021

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CHEMICAL MANAGEMENT

Global polyethylene demand boom likely, increasing the sustainability challenge

Article | June 17, 2021

IT FEELS LIKE several lifetimes ago. If you recall, way back in November-December 2019 Asian variable cost integrated naphtha-based polyethylene (PE) margins turned negative because of the increase in US capacity. Then in January the following year, deep Asian and Middle East operating rate cuts returned some order to the market. Then, bang, as we all know, the pandemic arrived and turned everything on its head. The pandemic has, in my view, accentuated trends that were already well underway. I believe this means that the supply-driven downturn that started in late 2019 will not return.Long before coronavirus upended everyone’s lives, PE demand was becoming increasingly divorced from GDP growth because of the shifting nature of end-use demand. Booming internet sales was, I believe, a major factor behind the split between the growth of the overall economies in the developed world plus China and PE demand.The average product bought online is dropped 17 times because of the large number of people involved in the logistics chain, according to Forbes. This had led to a surge in demand for protective packaging made not from PE and other polymers such as polypropylene, expandable polystyrene and PET films (I will look at their demand growth prospects in later posts).Despite sustainability pressures, the scale of demand for stuff bought online translated to a lot more consumption of virgin polymers.

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Spotlight

Clariant

Clariant is a globally leading specialty chemicals company, based in Muttenz near Basel/Switzerland. The company employs a total workforce of around 17 200. In the financial year 2015, Clariant recorded sales of CHF 5.807 billion for its continuing businesses. The company reports in four business areas: Care Chemicals, Catalysis & Energy, Natural Resources, and Plastics & Coatings. Clariant’s corporate strategy is based on five pillars: increase profitability, reposition portfolio, add value with sustainability, foster innovation and R&D, and intensify growth.

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