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Dorobantu Bodoc M.,Ecole Polytechnique - Palaiseau | Prat L.,Ecole Polytechnique - Palaiseau | Xuereb C.,Ecole Polytechnique - Palaiseau | Gourdon C.,Ecole Polytechnique - Palaiseau | Lasuye T.,INEOS ChlorVinyls
Chemical Engineering and Technology | Year: 2012

A novel capillary-based microfluidic device has been designed to follow the vinyl chloride polymerization reaction. Monodisperse droplets of 200μm diameter could be obtained by means of a co-flow generation system, each one being considered as a polymerization reactor. Monomer droplets were visualized in a microchannel with a high-speed camera. At the end of the reaction, PVC grains were observed with a scanning electron microscopy technique. Real-time non-invasive Raman measurement was performed on stationary vinyl chloride monomer droplets and provided values of effective reaction orders and rate constants. This microdevice allowed reaction investigation under difficult conditions of pressure and temperature with a minimal amount of reagents. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Agaciak P.,ESPCI ParisTech | Yahiaoui S.,ESPCI ParisTech | Djabourov M.,ESPCI ParisTech | Lasuye T.,INEOS ChlorVinyls
Colloids and Surfaces A: Physicochemical and Engineering Aspects | Year: 2015

Concentration of aqueous suspensions of solid particles (called slurries in industrial processes) is achieved by centrifugation at high accelerations and it is an important step in dry powder productions; dehydration precedes drying. In aqueous suspensions of porous particles, water is both the interstitial fluid, which disperses the particles and the imbibition fluid, which fills the pores inside particles. This is the case in the pastes of poly(vinyl)chloride (PVC) polymerized in suspensions after centrifugation. PVC grains are non-colloidal particles with diameters close to 150. μm and variable inner porosity, which are synthetized in aqueous solutions using dispersants such as various poly(vinyl)alcohols (PVA). In this paper we determine the dehydration by centrifugation of different grades PVC suspensions with laboratory scale experiments. It is shown that the humid pastes reach a pendular state at high accelerations and that the compaction of the grains and their surface properties determine the final retention of the water by capillary forces. In such conditions, internal water, inside the pores of the grains can be eliminated only by evaporation. Drying was investigated in controlled relative humidity atmospheres (. RH) in desiccators by measuring the equilibrium moisture content of the grains and the evaporation rates. The evaporation rate of the superficial water is similar to pure water and can be interpreted using Stefan's equation, whereas substantial differences exist between the total drying times of grades. © 2015 Elsevier B.V.

Patrick S.,INEOS ChlorVinyls | Patrick S.,Institute of Materials
Society of Plastics Engineers - EUROTEC 2011 Conference Proceedings | Year: 2011

The papers from the most recent IOM3 conference, PVC 2011, are used as the basis for this paper. The PVC market is reviewed on the basis of Europe's environmental challenges with management options being reshaped by global megatrends. The cost competitiveness of PVC products, energy saving from using PVC products and increasing recognition of our sustainable development progress can only serve our industry well into the future. The Voluntary Commitments of the past ten years (Vinyl 2010) and the next ten years (VinylPlus) are reviewed. Examples of educational initiatives in the UK to improve perceptions are also highlighted.

Azapagic A.,University of Manchester | Chahal S.,United Technologies | Leadbitter J.,INEOS ChlorVinyls | Pitts M.,Chemistry Innovation
Chemical Engineer | Year: 2011

A research team at the University of Manchester, led by Adisa Azapagic, has developed a carbon footprinting tool Carbon Calculations over the Life Cycle of Industrial Activities (CCaLC). The tool is aimed at assisting businesses and professionals to estimate and manage the climate change impact of their activities along the supply chains. Suitable for both large companies and SMEs, CCaLC can be used for quick, broad-brush analyses or detailed estimations of carbon footprints, depending on the aims of the study. CCaLC contains carbon footprint data for over 5000 different materials, energy, transport, packaging, and waste management options. Two further tools within the CCaLC tools family include the PVC sustainability tool, developed specifically for the PVC industry and the CCaLC optimization tool. It is also possible to estimate economic costs and value added within CCaLC, while the latter provides a powerful tool for managing carbon emissions at minimum economic costs.

Agaciak P.,ESPCI ParisTech | Yahiaoui S.,ESPCI ParisTech | Djabourov M.,ESPCI ParisTech | Lasuye T.,INEOS ChlorVinyls
Colloids and Surfaces A: Physicochemical and Engineering Aspects | Year: 2015

This paper analyzes the drying rates of humid porous grains of poly(vinyl)chloride PVC by thermogravimetry. Grains have variable volume fractions of pores, representing between 16 and 33%. g water/g PVC, with pore sizes varying between 0.6 and 1. μm. It is shown that the humid cakes exhibit three different drying rate regimes at constant temperature, characterizing evaporation of free water, of interstitial water and of water inside the pores. The constant rate period (CRP) and the falling rate period (FRP) of drying are clearly identified. The drying rates and drying times are presented in adimensional units by comparison with evaporation of pure water. The thermogravimetric analysis identifies a fraction of water which dries very slowly inside the pores. A method of quantifying the strongly bound water is presented. Numerical simulations of water evaporation were performed on a 2D array of channels and illustrate the contribution of geometrical effects (diameter of channels, tortuosity, etc.) in pore drying. Visual observations of the drying of droplets of solutions containing dispersants used in PVC synthesis show interesting patterns. The phase separated solutions of dispersants are analyzed and their role in drying is highlighted. © 2015 Elsevier B.V.

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