Vinyl Chloride Essay

3023 words - 13 pages

201

7 Vinyl Chloride Monomer Process
7.1 Basis of Design 7.1.1 Problem Statement

Vinyl chloride monomer (VCM) is one of the leading chemicals used mainly for manufacturing polyvinyl chloride (PVC). The PVC worldwide production capacity in 2005 was of about 35 million tons per year, with an annual growth of about 3%, placed after polyolefines but before styrene polymers. In the 1990s the largest plant in the USA had a capacity of about 635 ktons [1], but today there are several plants over one million tons. At this scale even incremental improvements in technology have a significant economic impact. Computer simulation, process optimization and advanced computer-control techniques play a ...view middle of the document...

Alexandre C. Dimian and Costin Sorin Bildea Copyright © 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim ISBN: 978-3-527-31403-4

202

7 Vinyl Chloride Monomer Process
Table 7.1 Purity specifications for vinyl chloride [2].

Impurity Acetylene Acidity, as HCl by wt Acetaldehyde Alkalinity, as NaoH by wt. Butadiene 1-butene, 2-butene Ethylene, propylene Ethylene, dichloride (EDC) Nonvolatiles Water Iron, by wt.

Maximum level (ppm) 2 0.5 0 0.3 6 3, 0.5 4, 8 10 150 200 0.25

7.1.2 Health and Safety

Health and safety regulations (OSHA) require the monitoring of concentrations of harmful species in all facilities where VCM is produced or used. The employees should not be exposed to more than 1 ppm over 8 h, or no more than 5 ppm for periods exceeding 15 min. Chronic exposures to more than 100 ppm may lead to serious diseases. On the other hand, VCM is flammable by heat, flame and oxidizing agents. Large fires are difficult to extinguish. Because of possible peroxide formation, the VCM must be stored or transported under an inert atmosphere. The use of stabilizers prevents polymerization during processing and storage. VCM is generally transported in railroad tank cars and tank trucks.
7.1.3 Economic Indices

Table 7.2 presents some economic indices of a modern VCM technology [6], in which stoichiometric values are indicated in parentheses. The yield for chlorine may rise over 98%, the yield for ethylene being slightly lower because of losses by combustion.

7.2 Reactions and Thermodynamics 7.2.1 Process Steps

Most of the VCM technologies are based on “balanced” processes. By this is meant that all intermediates and byproducts are recycled in a way that ensures a tight

7.2 Reactions and Thermodynamics
Table 7.2 Economic indices of VCM processes [6].

203

Raw material (kg/t VCM) • ethylene • chlorine • oxygen Utility/t VCM • electric power (kWh) • steam (t) • cooling water (m3) • fuel (Mcal) Operators (men/shift)

462 (448) 578–585 (568) 131–139 (128) 105–110 0.05–0.20 150–175 660–700 4

closure of the material balance to only VCM as the final product, starting from ethylene, chlorine and oxygen. The main chemical steps are explained briefly below. 1. Direct chlorination of ethylene to 1,2-ethylenedichloride (EDC): C2H4 + Cl2 → C2H4Cl2 + 218 kJ/mol 2. Thermal cracking (pyrolysis) of EDC to VCM: C2H4Cl2 → C2H3Cl + HCl − 71 kJ/mol 3. Recovery of HCl and oxychlorination of ethylene to EDC: C2H4 + 2HCl + 0.5O2 → C2H4Cl2 + H2O + 238 kJ/mol Hence, an ideal balanced process can be described by the overall equation: C2H4 + 0.5Cl2 + 0.25O2 → C2H3Cl + 0.5H2O + 192.5 kJ/mol Therefore, half of the ethylene and the whole of the chlorine are fed to direct chlorination, while the other half of the ethylene goes to oxychlorination. The process block diagram consists of three plants, as shown in Figure 7.1. Note that the purification of all EDC streams produced by synthesis, as well as recycled, can be done in a common separation section. In...

Other Essays Like Vinyl Chloride

Dhirubhai & Reliance Essay

4119 words - 17 pages then integrated sideways manufacturing linear alkyl benzene (LAB) used by detergent manufacturers, thermoplastics like poly vinyl chloride (PVC), high density poly ethylene (HDPE) and low density poly ethylene (LDPE) used by plastic processors. Gradually, Reliance started manufacturing petrochemical intermediaries like paraxylene, n-paraffin and mono ethylene glycol (MEG), and ethylene, the basic raw material for all petrochemical bi-products and

Technology, Environment and Society Essay

5356 words - 22 pages garbage • Vinyl Chloride • Radioactive air pollutants Effects of air pollution 1. Health effects • Chronic disease, Respiratory illness: bronchitis, asthma, lung cancer • Temporary effect: nose or eye or throat irritation, coughing, chest pain, general discomfort 2. Damage to material objects • Soiling and deterioration of building surface, corrosion of metals, weakening of rubber, textile

Environmental Hazards of Plastics with Reference to Polythene

3054 words - 13 pages most solvents it’s also used for household cleaners including laundry detergent, shampoo. HDPE is also accepted by most curbside recycling programs and is recycled into bottles for non-food items including motor oil and antifreeze and can be used to create plastic lumber, flowerpots, and recycling bins. 3. Polyvinyl Chloride (PVC, Vinyl): You probably won’t find this one on any of your household items because it is typically used to make

Water Pollution

2903 words - 12 pages electronics manufacturing) and tetrachloroethylene used in the dry cleaning industry (note latest advances in liquid carbon dioxide in dry cleaning that avoids all use of chemicals). Both of these chemicals, which are carcinogens themselves, undergo partial decomposition reactions, leading to new hazardous chemicals (including dichloroethylene and vinyl chloride). Groundwater pollution is much more difficult to abate than surface pollution because

Water Pollution

2781 words - 12 pages cleaning industry (note latest advances in liquid carbon dioxide in dry cleaning that avoids all use of chemicals). Both of these chemicals, which are carcinogens themselves, undergo partial decomposition reactions, leading to new hazardous chemicals (including dichloroethylene and vinyl chloride). Groundwater pollution is much more difficult to abate than surface pollution because groundwater can move great distances through unseen aquifers

What is cancer? - 1

3496 words - 14 pages as painters, construction workers, and those in the chemical industry) have an increased risk of cancer. Many studies have shown that exposure to asbestos, benzene, benzidine, cadmium, nickel, or vinyl chloride in the workplace can cause cancer. Follow instructions and safety tips to avoid or reduce contact with harmful substances both at work and at home. Although the risk is highest for workers with years of exposure, it makes sense to be

Footwear and Leathergoods Sector Footwear Making Nc Ii

2904 words - 12 pages | | |Microcellular Rubber | | |Resin Rubber | | |Polyvinyl Chloride (PVC

The Separation Of Capital Ownership And Control

1577 words - 7 pages The argument of whether the separation of capital ownership and control is an efficient form of organization has constantly been a controversial issue. The criticism whether the controllers’ act is in the best interest of the owners’ wills never end as long as hired managers operate management. As the number of public companies has been increasing over the course of this century, meanwhile the American style of contact based corporation has

The Versatility And Flexibility Of OLED's

1014 words - 5 pages In April 1, 2002, organic light emitting diodes gain rise in the scientific community with their published, more practical form at Ames Laboratory. “Scientists at the U.S. Department of Energy's Ames Laboratory, in collaboration with scientists at the University of Michigan, Ann Arbor, have developed and demonstrated a novel, fluorescence-based chemical sensor that is more compact, versatile and less expensive than existing technology of its

Comparing The Moral Virtues Of Antony And Julian The Apostate

1103 words - 5 pages Roman emperor Julian the Apostate and Christian leader Antony both exhibited many qualities of character during their existence. Both of them led very distinctive lives although shared several ethical values. Book 25 of “The Later Roman Empire” and the book “Early Christian Lives” show concrete evidence of this. In the following essay, I will argue how both leaders’ lives were devoted to their religious beliefs and their mutual cardinal virtues

Living In A Cashless Society

1637 words - 7 pages Money in a traditional sense no longer exists. Money is becoming much of a concept than a physical material, and most ordinary bitter have not see the reality of the switch. People today are using credit and debit cards on a regular basis and in everyday situations such as meal purchased at fast food, highway tolls, clothing, groceries, gas stations, etc. all of these means of systems could be regarded as a cashless society or world. The question

Related Papers

Lung Cancer Outline

679 words - 3 pages . Vinyl Chloride B. Second-hand Smoke (Environmental tobacco smoke) 1. Second hand smoke itself is labeled as a human carcinogen 2. Inhaling second hand causes lung cancer in non-smoking adults C. Radon 1. The Second leading cause of lung cancer. 2. Colorless, odorless gas that is radioactive. Caused by the break down of uranium D

Smog Over La Essay

1127 words - 5 pages ), and vinyl chloride. In the 1990’s this list was expanded to include 189 substances, and by the end of the 1990’s regulations were put in place for the “major sources”, which require the emission of no more than ten tons of any of these substances and no more than twenty five tons of any combination of them per year. Air pollution that worsens the global air quality is mostly generated by the wealthier, more populated nations. America has a

Zero Waste Society Essay

1216 words - 5 pages (Poly Vinyl Chloride),PS(Poly Styrene),try to utilize the things for ur daily convenencial needs,requirements. Art of education “inside school & college” My ambition & dream to change the course of ur life .I want to die before that I put some sweetest returns, in order to make the society to be glorious,attractive.My aspiration is somewhat innovative,which is impossible ,dared to imagine .Since 1947,Technical Education Quality Improvent

Organic Reaction Mechanism Essay

2098 words - 9 pages a sp3 hybridized carbon atom. • Alkyl halides are classified as primary (10), secondary (20), or tertiary (30), depending on the number of carbons bonded to the carbon with the halogen atom. • The halogen atom in halides is often denoted by the symbol “X”. EDdeS CH 2009 Lecture 10 2009 16 Examples of primary, secondary and tertiary alkyl halides: There are other types of organic halides. These include: Reactivities of vinyl and