Design Project vinyl acetate monomer feasibility study PDF

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Design Project vinyl acetate monomer feasibility study ...

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Vinyl Acetate Monomer Production Technology Selection Study

School of Engineering and Computer Science

Hull University

Student Number: 201603560

Submission Date: 17/12/2019

Due Date: 17/12/2019

Abstract This report will review and analyse existing process routes in Vinyl acetate monomer production in terms of Technical feasibility, safety, sustainability and economic performance. Each will be discussed and analysed to conclude the most feasible process route based on a design intent of 300,000 tonnes per annum of industrial grade product.

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Tab Table le o off C Con on onten ten tents ts Introduction ..................................................................................................................................... 5 Structure and properties ............................................................................................................. 5 Applications of VAM in industry ................................................................................................ 6 Polyvinyl acetate (PVA) ........................................................................................................... 6 Polyvinyl alcohol (PVOH) ....................................................................................................... 6 Polyvinyl Butyral (PVB) .......................................................................................................... 7 Ethylene-Vinyl Acetate (EVA) ................................................................................................ 7 Market Analysis ........................................................................................................................... 7 Safety Analysis of Reactants and Products ................................................................................. 9 Process Routes ............................................................................................................................... 10 Process Route 1: Acetic acid, Ethylene and Oxygen ................................................................. 10 Reactants and Conditions ...................................................................................................... 10 Kinetics................................................................................................................................... 11 Thermodynamic Calculations ............................................................................................... 12 Environment Impact Assessment (EIA) ................................................................................ 13 Sustainability ......................................................................................................................... 14 Process Route 2: Acetic Acid and Acetylene ............................................................................. 15 Reactants and Conditions ...................................................................................................... 15 Kinetics and Thermodynamics .............................................................................................. 16 Environment Impact Assessment and Sustainability ........................................................... 16 British petroleum (BP) Leap process ........................................................................................ 16 Process Route 3: Acetaldehyde and acetic anhydride .............................................................. 17 Reactants and conditions .......................................................................................................... 17 Kinetics and Thermodynamics .............................................................................................. 18 Environment Impact Assessment and Sustainability ........................................................... 18 Economics ...................................................................................................................................... 19 Class 5 Fixed Capital Cost Estimate ......................................................................................... 19 2

Variable cost of production ....................................................................................................... 20 Revenues, Margins and Profits ................................................................................................. 21 Modes of finance ........................................................................................................................ 22 Project Evaluation and Sensitivity Analysis ............................................................................. 22 Return on investment (ROI) .................................................................................................. 22 Cash Flow............................................................................................................................... 22 Net Present Value .......................................................................................................................... 23 Conclusion ..................................................................................................................................... 25 References ...................................................................................................................................... 26

Table o off Figu Figures res Figure 1: National Fire Assocition Scale of Reactants and Products (CameoChemicals, 2019) ........... 9 Figure 2: Global VAM Demand by End User (Nexant, 2018) ............................................................ 6 Figure 3: Global VAM Supply, Demand and Trade (Nexant, 2017) ................................................... 8 Figure 4: Global Consumption of VAM 2017 (IHS Markit, 2018) ...................................................... 8 Figure 5: Block Flow Diagram of Process Route 1 ........................................................................... 10 Figure 6: Energy Integration Around Chemical Reactor (Dimian,A. Bildea,C. 2008) ....................... 14 Figure 7: Block Flow Diagram of Process Route 2 ........................................................................... 15 Figure 8: Block Flow Diagram of Process Route 3 (1) ..................................................................... 17 Figure 9: Block Flow Diagram of Process Route 3 (2) ..................................................................... 18 Figure 10: Process Route 1 Cumulative Net Cash Flow Over Project Lifetime ................................. 24 Figure 11: Process Route 2 Cumulative Net Cash Flow Over Project Lifetime ................................. 24

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Table o off Equa Equations tions Equation 1: Process Route 1 Main and Side Chemical Reaction ....................................................... 10 Equation 2: Reaction Rate Law and Rate Constant ........................................................................... 11 Equation 3: Clausius-Clapeyron Molar Enthalpy of Vaporisation ..................................................... 12 Equation 4: Standard Enthalpy Change of the Reaction .................................................................... 12 Equation 5: Standard Entropy change of the Reaction ...................................................................... 12 Equation 6: Change in Gibbs Free Energy ....................................................................................... 12 Equation 7: Kirchhoff’s Law at Constant Pressure ........................................................................... 12 Equation 8: Van't Hoff Isochore Equilibrium Constant..................................................................... 12 Equation 9: Process Route 2 Chemical Reaction .............................................................................. 15 Equation 10: Route 3 Chemical Reaction (1) ................................................................................... 17 Equation 11: Process Route 3 Chemical Reaction (2) ....................................................................... 17 Equation 12: Step Count Method (USD Gulf Coast 2000 Basis) ...................................................... 19 Equation 13: Cost Escalation and Location Factor ........................................................................... 19 Equation 14: Total Fixed Capital Cost ............................................................................................. 19 Equation 15: Historic Cost Method Estimation (USD Gulf Coast 2006 Basis) .................................. 20 Equation 16: Debt to Equity Ratio .................................................................................................... 22 Equation 17: Cost of Capital............................................................................................................. 22 Equation 18: Return on Investment ................................................................................................. 22

Table of Tables Table 1: Properties for Industrial Vinyl Acetate (Dimian,A. Bildea,C. 2008) ...................................... 5 Table 2: National Fire Protection Association (NFPA) Rating of Reactants and Products ................... 9 Table 3: Total Fixed Capital Cost of Process Route 2 and 3 ............................................................. 19 Table 4: Route 1 Variable Cost of Production .................................................................................. 20 Table 5: Route 2 Variable Cost of Production .................................................................................. 20 Table 6: Fixed Cost of Production ................................................................................................... 21 Table 7: Revenues, Margins and Profits ........................................................................................... 21 Table 8: Cash flow of Project .......................................................................................................... 22 Table 9: Net Present Value of Future Cash Flows ............................................................................. 23

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Introduction The chemical industry both dominates and underpins global manufacturing markets and economic growth, the production of bulk commodity chemicals has continued to grow to satisfy global market demand across all manufacturing sectors. ONS (2017) reported that In the UK alone chemical exports and imports amounted to 50 billion GBP in 2016 with a gross value added (GVA) increase of 3.6% from the previous year with the total global chemical import market worth around 1.2 trillion GBP with continued growth year upon yea The Global production of vinyl acetate monomer (VAM) in 2005 was about 5 million tons per year with USA, China and western Europe leading in terms of consumption worldwide (Dimian,A. Bildea,C. 2008). European demand far outstretches internal supply since the closure of INEOS unit at Saltend chemical park in the Humber cluster and the need for a high output source is in the interest of the private investor and the European union chemical manufacturing industry which is currently reliant upon the consolidated market dominated by Asia and the USA.

Structure and properties VAM is an amorphous polymer with distinct characteristics permitting applications to various industry sectors, specific industrial properties are listed in table 1, each of which will adopted throughout the report. Table 1: Properties for Industrial Vinyl Acetate (Dimian,A. Bildea,C. 2008)

Not following each industrial expectation lower s the selectivity and monetary value of the final product

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Applications of VAM in industry Although many compounds have the ability to polymerize, VAM is exceptional in how easily this process can occur either in bulk, solution, emulsion or suspension. Each of these polymerization techniques lead to consumer products of varying applications each of which VAM is the precursor of but in order to store and distribute hydroquinone must be used as an inhibitor to prevent Polymerisation and the final product cooled to 35 °C .

KEY Poly vinyl Acetate Ethylene-Vinyl Acetate

Polyvinyl Alcohol Polyvinyl Butyral

Figure 1: Global VAM Demand by End User (Nexant, 2018)

Polyvinyl acetate (PVA) PVA is the dominant derivative, when mixed with water VAM’s partial solubility results in a suspension of the discontinuous phase of droplets in the continuous phase of water resulting in polymerization (Grulke, E. 1994). These dispersions of small droplets are then set by loss of moisture leaving the droplets to coalesce to form a continuous solid (Foot, P . et al. 2007). This coagulation of particles creates an adhesive nature that is extremely desirable in manufacturing of adhesives and sealants.

Polyvinyl alcohol (PVOH) PVOH is extremely similar to PVA but an alcohol side chain substitutes the acetate side chain, this is due to the emulsion polymerisation process by which PVA is dispersed as fine droplets using high levels of surfactants ca using polymerization through the free radical method (Grulke, E. 1994). Unlike PVA, PVOH is relatively thermodynamically stable and does not intend to immediately coagulate, along with the colloid nature this creates a smooth glossy finish which is completely soluble in water and resistant to solvents and oils the properties allow uses across various industries including paper surface treatment and textile finishes.

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Polyvinyl Butyral (PVB) PVB is under the ‘other’ derivatives of VAM and takes a small yet still essential part of the market. It is a derived from a condensation reaction involving PVA generating copolymer that adheres to nonporous solids such as metals or glass and holds good impact resistance for applications in safety glass (Polymer Database, 2019).

Ethylene-Vinyl Acetate (EVA) EVA is a thermoplastic resin as a result of the co-polymerisation of ethylene and VAM which creates a random copolymer. As the VAM content increases, crystallinity decreases until VAM content reaches 50% making the EVA totally amorphous (Emblem, A. 2012). EVA holds good clarity and stress-crack resistance to retain its flexibility at low temperatures, features which are necessary in processes that involve extrusion and injection & blow moulding for speciality parts (Rosato, D. 1991).

Market Analysis Global VAM market demand was 6000 kilotons in 2013 and is expected to reach 8000 kilotons by 2020 growing at a compound annual growth rate (CAGR) of 4.4% over the 7 years. The global VAM market is concentrated by a few companies which dominate production, Asia Pacific is the largest consuming region accounting for 47.1% of the total market volume in 2013 due to increasing construction spending coupled with growing automotive production. This region is expected to grow at an estimated CAGR of 4.7% by 2020, because of this vast expansion this area is the dominant figure east of the Atlantic Ocean. (Kumar, S. 2015) The majority of VAM capacity increase is the result of China between 2013 to 2016 with the addition of 1.5 million tons per year to Global VAM capacity, father capacity is expected but at a slowed rate with global operating states holding relatively stable at an average of 80% despite huge capacity additions (Nexa nt. 2018). In the European market (ICIS Pricing, 2014) reported spot prices as of 2014 at 850 EUR per ton in comparison to 880 EUR per ton in 2004. This demise in price is relatively small in comparison to the drastic increase in output mentioned in china over the same period, it is safe to say the adaptability and robustness of the market remains strong to date and is predicted to retain growth at a steady rate. Figure 2 displays both actual and predicted market growth in terms of consumption in line with production at a steady rising level but also the global capacity and operating rate which currently shows operating at a surplus although this is set to be flatlined by 2022.

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Figure 2: Global VAM Supply, Demand and Trade (Nexant, 2017)

Manufactures in the Americas and Asia Pacific hold an advantage due to relatively cheap and easily available natural resources for VAM production in addition with lenient government Environmental and manufacturing policies. To even trade relations the European Union (EU) increased tariffs on some countries including Saudi Arabia from 2% to 5.5% (ICIS Pricing, 2014) to even the playing field and incite fair competition for EU VAM manufactures. The major trade occurs between North America to South America and Western Europe and from Asia Pacific to Western Europe but the increase in import tariffs paired with the long-haul logistics to the EU rises the manufacture cost of the end user products resulting in lower profits and growth across all VAM application sectors. The input of a 300,000 tonne VAM plant would account for 3.75% of global production and significantly increase competitiveness in the EU market.

Figure 3: Global Consumption of VAM 2017 (IHS Markit, 2018)

Western Europe remains in the top three global consumers but relies on huge imports to satisfy demand unlike USA and china whereby VAM is oversupplied, clearly a plant central to western Europe is vital to meet the under supplied demand.

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Safety Analysis of Reactants and Products Table 2: National Fire Protection Association (NFPA) Rating of Reactants and Products

Material

Chemical Formula

Process

Safety

Route Product

Health

Fire

Reactivity

Hazard VAM

𝐶𝐻2 = 𝐶𝐻𝑂𝐶𝑂𝐶𝐻3

All

2

3

2

1

2

4

2

1, 2, 3

3

2

0

2

0

4

3

3

2

4

2

3

3

2

1

3

0

1

0

Raw Material Ethylene Acetic acid Acetylene Acetaldehyde Acetic anhydride ethylidene

𝐶2 𝐻4

𝐶𝐻3 𝐶𝑂𝑂𝐻 𝐻𝐶 ≡ 𝐶𝐻 𝐶𝐻3 𝐶𝐻𝑂

(𝐶𝐻3 𝐶𝑂2 )2 𝑂

𝐶𝐻2 = 𝐶𝐻𝑂𝐶𝑂𝐶𝐻3

diacetate (EDA)

Figure 4: National fire protection association Scale of Reactants and Products (CameoChemicals, 2019)

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Process Routes Process Route 1: Acetic acid, Ethylene and Oxygen Reactants and Conditions Acetic acid and ethylene are fed to a vaporiser operating at 6.7 Bara and 423 K, this stream is fed to a cooled tubular reactor along with oxygen operating at 421 K and 6.1 Bar a (Luyben, W. 2011). The following vapour phase reactions occur: 1

Main Reaction: 𝐶2 𝐻4 + 𝐶𝐻3 𝐶𝑂𝑂𝐻 + 2 𝑂2 → 𝐶𝐻2 = 𝐶𝐻𝑂𝐶𝑂𝐶𝐻3 + 𝐻2 𝑂 Side Reaction: 𝐶2 𝐻4 + 3𝑂2 → 2𝐶𝑂2 + 2𝐻2 𝑂 Equation 1:Process Route 1 Main and Side Chemical Reaction

The main reaction generates VAM but the side reaction generates an undesired by-product as carbon dioxide. The reacted gas is then fed to a separator via a cooler reducing the temperature to 310 K with unreacted acetic acid, water and VAM condensing in the separator. Unreacted ethylene and oxygen along with carbon dioxide and uncondensed VAM are sent to an initial absorption column where uncondensed VAM is absorbed by acetic acid acting as a solvent in a wash stream with the remainder fed to a second absorption column using MEA as a solvent to remove the CO2. The remainder of the gas is recycled to the vaporiser through a compressor and the VAM crude from each stage is sent to the de-ethanizer distillation column to remove ethylene with the bottoms fed to the azeotropic distillation column, here acetic acid is condensed and recycled to the vaporiser with the aqueous VAM mixture fed to a decanter and separated (Luyben, W. 2011).

Figure 1: Block Flow Diagram of Process Route 1

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Kinetics...