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CLEANER PR PETROC 2015 RODUCTION GUIDELINE CHEMICAL INDUSTRIES Gujarat Cleaner Production Centre (Established by Industries & Mines Department, GoG) ENVIS Centre on: Cleaner Production/Technology Supported by: Ministry of Environment, Forest & Climate Government of India Block No: 11-12, 3 rd Floor, UdhyogBhavan, Gandhinagar Phone: + 91 (079) 232 44 147 Mail: [email protected] ; [email protected]; Website: www.gcpcgujarat.org.in, www.gcpcenvis.nic.in ES IN e Change,
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CLEANER PRODUCTION GUIDELINES IN PETROCHEMICAL INDUSTRIES

2015

Gujarat Cleaner Production Centre(Established by Industries & Mines ENVIS Centre on: Cleaner Production/TechnologySupported byGovernment of IndiaBlock NoPhone:MailWebsite

CLEANER PRODUCTION GUIDELINES IN PETROCHEMICAL INDUSTRIES

Gujarat Cleaner Production Centre(Established by Industries & Mines Department, GoG)ENVIS Centre on: Cleaner Production/TechnologySupported by: Ministry of Environment, Forest & Climate Change, Government of IndiaBlock No: 11-12, 3rd Floor, UdhyogBhavan, GandhinagarPhone: + 91 (079) 232 44 147Mail: [email protected] ; [email protected]; Website: www.gcpcgujarat.org.in, www.gcpcenvis.nic.in

CLEANER PRODUCTION GUIDELINES IN

: Ministry of Environment, Forest & Climate Change,

; [email protected];

INTRODUCTION TO PETROCHEMICAL INDUSTRY

India is having 3.17 million square kilometers land mass and over 1.22 billion population and is one of the fastest growing economies in the world. It has well-developed Process Industry. India has petroleum refining capacity of over 194 Million Tones per Annum (MTPA). The world's largest grass root refinery with 32 MTPA capacities is located in India. It has a number of gas cracker complexes with downstream facility producing 8 MTPA plastics and polymers.

The petrochemical industry in India has been one of the fastest growing industries in the country. Since the beginning, the industry has shown an enviable rate of growth. Indian petrochemical industry grew at a rate of ~11% in 2010-11. The outlook for 2011-12 is also stable and the chemicals market is expected to grow at 11-13% p.a. over the next five years

Petrochemicals are the derivatives of crude oil and natural gas. Olefins (ethylene, propylene & butadiene) and Aromatics (benzene, toluene & xylene) are the major building blocks from which most Chemicals and Petrochemicals are produced. They are used in dyes, synthetic fibres, rubbers, plastics, pharmaceutical bulk drugs, industrial appliances, packaging industry, detergents (surfactants).

Structure of Petrochemical Industry

Highlights of processes for different Petrochemicals

The adjacent diagram schematically depicts the major hydrocarbon sources used in producing petrochemicals are

Methane, ethane, propane and butanes: Obtained primarily from natural gas processing plants.

Naphtha obtained from petroleum refineries. Benzene, toluene and xylene, as a whole referred to as BTX and primarily obtained from

petroleum refineries by extraction from the reformate produced in catalytic reformers. Gas oil obtained from petroleum refineries.

Methane and BTX are used directly as feedstocks for producing petrochemicals. However, the ethane, propane, butanes, naphtha and gas oil serve as optional feedstocks for steam-assisted thermal cracking plants referred to as steam crackers that produce these intermediate petrochemical feedstock

Ethylene

Propylene

Butene and butadiene

Benzene

C1 compounds (with one carbon atom in their molecule) manufactured at petrochemical plantsinclude methanol, formaldehyde, and halogenated hydrocarbons. Formaldehyde is used in themanufacture of plastic resins, including phenolic, urea, and melamine resins. Halogenated hydrocarbons are used in the manufacture of silicone, solvents, refrigerants, and degreasing agents.

Olefins (organics having at least one double bond for carbon atoms) are typically manufactured from the steam cracking of hydrocarbons such as naphtha.

Major olefins manufactured include ethylene (C2, since it has two carbon atoms),propylene (C3), butadiene (C4), and acetylene. The olefins manufactured are used in the manufacture of polyethylene, including low-density polyethylene (LDPE) and high-density polyethylene(HDPE), and for polystyrene, polyvinyl chloride, ethylene glycol (used along with dimethylterphthalate, DMT, as feedstock to the polyester manufacturing process), ethanol amines (used assolvents), polyvinyl acetate (used in plastics), polyisoprene (used for synthetic rubber manufacture), polypropylene, acetone (used as a solvent and in cosmetics), isopropanol (used as a solvent and in pharmaceuticals manufacturing), acrylonitrile (used in the manufacture of acrylic fibers and nitrile rubber), propylene glycol (used in pharmaceutical manufacturing), and polyurethane.

Butadiene is used in the manufacture of polybutadiene rubber (PBR) and styrene butadiene rubber (SBR). Other C4 compounds manufactured include butanol, which is used in themanufacture of solvents such as methyl ethyl ketone.

The major aromatics (organics having at least one ring structure with six carbon atoms) manufactured include benzene, toluene, xylene, and naphthalene. Other aromatics manufactured include phenol, chlorobenzene, styrene, phthalic and maleic anhydride, nitrobenzene, and aniline.Benzene is generally recovered from cracker streams at petrochemical plants and is used for the manufacture of phenol, styrene, aniline, nitrobenzene, sulfonated detergents, pesticidessuch as hexachlorobenzene, cyclohexane (an important intermediate in synthetic fiber manufacture), and caprolactam, used in the manufacture of nylon. Benzene is also used as a solvent.

The main uses of toluene are as a solvent in paints, rubber, and plastic cements and as a feed stock in the manufacture of organic chemicals, explosives, detergents, and polyurethane foams.Xylenes (which exist as three isomers) are used in the manufacture of DMT, alkyd resins, andplasticizers. Naphthalene is mainly used in the manufacture of dyes, pharmaceuticals, insect repellents, and phthalic anhydride (used in the manufacture of alkyd resins, plasticizers, andpolyester).

The largest user of phenol in the form of thermosetting resins is the plastics industry. Phenol is also used as a solvent and in the manufacture of intermediates for pesticides, pharmaceuticals,and dyestuffs. Styrene is used in the manufacture of synthetic rubber and polystyrene resins.Phthalic anhydride is used in the manufacture of DMT, alkyd resins, and plasticizers such asphthalates.

Maleic anhydride is used in themanufacture of polyesters and, to some extent, for alkyd resins.Minor uses include the manufacture of malathion and soil conditioners. Nitrobenzene is used in the manufacture of aniline, benzidine, and dyestuffs and as a solvent in polishes. Aniline is used in the manufacture of dyes, including azo dyes, and rubber chemicals such as vulcanization accelerators and antioxidants.

List of significant petrochemicals and their derivatives

The following is a partial list of the major commercial petrochemicals and their derivatives:

Ethylene - the simplest olefin; used as a chemical feedstock and ripening stimulant. Following chart shows the ethylene and its Derivatives

Propylene - used as a monomer and a chemical feedstock. Following chart shows the propylene and its Derivatives

Benzene - the simplest aromatic hydrocarbon. Following chart shows the propylene and its Derivatives

Toluene - methylbenzene; can be a solvent or precursor for other chemicals. Following chart shows the toluene and its Derivatives.

Mixed xylenes - Any of three dimethylbenzene isomers, could be a solvent but more often precursor chemicals. Following chart shows the mixed xylene and its Derivatives.

Emissions in Petrochemical Industry

Air Emission

In the petrochemical and refinery sector large amount of hydrocarbons are handled. Even if diffuse emissions represent 0.1% of the throughput, handling 10 million tonnes of crude oil will amount to 10.000 ton of VOC which has a large environmental burden and also a significant cost.

The very high number of potential diffuse emissions from: Filling and emptying of storage tanks The expansion of the contents of storage tanks due to heating and cooling throughout the day The vacuum pumps used for a variety of processes Literally thousands of pipe and equipment joints. Sources are spread over a very large area some of them are high above ground Some potential leaking points are tight when installed but will leak eventually.

Water Emission

Petrochemical units generate wastewaters from process operation such as: Vapor condensation Cooling tower Blow down Storm water run offIf barometric condensers are used in vacuum distillation, significant amounts of oily waste water can be generated. Oily sour water is also generated in the fractionators.

Solid Waste

Petrochemical plants also generate solid waste and sludge. Some of which may be considered hazardous because of the presence of toxic organics and heavy metals. Spent caustic and other hazardous wastes such as distillation residues associated with units handling acetaldehyde, acetonitrile, benzyl chloride, carbon tetra chloride, cumene phallic anhydride,nitrobenzene, methyl pyridine, toluene di-isocyanate, tricholoro ethane, tricholoro ethylene, aniline, chlorobenzenes, dimethyl hydrazine, ethylene dibromide, toluenediamine, epichorohydrin, ethyl chloride, ethylene dichloride and vinyl chloride may be generated in significant quantities.

Environmental Issues in Petrochemical Industry and CP options

Simple techniques such as the use of infra-red photography from a light aero plane can be used to identify significant emission points from a refinery or petrochemical complex. Other techniques such as light detection and ranging techniques (LIDAR) and the use of Solar Occultation Flux which uses the absorption of solar infra red by the plume of VOC may also be used.

In the petrochemical industry, where large volumes of chemical and oil products are stored in tanks, a lot of experience has been gained on preventing and reducing emissions.

The following techniques are important [BREF on Storage]: Tank design Inspection, maintenance and monitoring Floating, flexible and fixed covers Domes Tank colour to reflect sunlight Solar shields Natural tank cooling External and internal floating roofs and the roof seals Pressure and vacuum relief valves Draining systems Vapour balancing and treatment, and Mixing and sludge removal.

By applying aboveground closed piping in new situations, leaks and spillage can be identified quickly and action taken to stop leaks. Leak detection and repair (LDAR) is one of the BAT conclusions in both cases and a programme of leak detection should be implemented using sniffers to identify leaks from joints in equipment and pipework.

Process optimisation and minimisation of emissions such as thermal or mechanical pre-treatment of secondary material to minimise organic contamination of the feed.

The use of sealed process units to prevent fugitive emissions, allow heat recovery and allow the collection of process gases for other use (e.g. CO as a fuel and SO2 as sulphuric acid) or to be abated.

The use of semi-sealed process units where sealed funits are not available.

The minimisation of material transfers between processes.

Where such transfers are unavoidable, the use of sealed pipelines.

In some cases, restricting techniques to those that avoid material transfers would prevent the recovery of some secondary materials that would otherwise enter the waste stream. In these cases the use of secondary or tertiary fume collection is appropriate.

Hooding and ductwork for the local exhaust ventilation equipment designed to capture the gases produced

Furnace or reactor enclosures may be required to prevent release of fume losses into the atmosphere.

Where primary extraction and enclosure are likely to be ineffective, then the furnace can be fully closed and ventilation air drawn off by extraction fans to a suitable treatment and discharge system.

Roofline collection of fume is very energy consuming and should be a last resort.

An important established practice to achieve good extraction is the use of automatic controls for dampers so that it is possible to target the extraction effort to the source of fume without using too much energy. The controls enable the extraction point to be changed automatically during different stages of the process. For example, charging and tapping of furnaces do not usually occur at the same time and so the charging and tapping points can be designed to be close together so that only one extraction point is needed. The extraction point is also designed to allow good access to the furnace and give a good rate of extraction. The hooding is constructed robustly and is maintained adequately.

Use nonchrome-based additives in cooling water.

Use long-life catalysts and regeneration to extend the cycle.

Recycle cooling water and treated wastewater to the extent feasible.

Recover and reuse spent solvents and other chemicals to the extent feasible.

Segregate process wastewaters from storm water system

Optimize the frequency of tank and equipment cleaning.

Prevent solids and oily wastes from entering the drainage system.

Establish and maintain an emergency preparedness and response plan.

Petrochemical wastewaters often require a combination of treatment methods to remove oil and other contaminants before discharge. Separation of different streams (such as stormwater) is essential to minimize treatment requirements.

Oil is recovered using separation techniques. For heavy metals, a combination of oxidation/reduction, precipitation, and filtration is used.

For organics, a combination of air or steam stripping, granular activated carbon, wet oxidation, ion exchange, reverse osmosis, and electrodialysis is used. A typical system may include neutralization, coagulation/flocculation, flotation/sedimentation/filtration, biodegradation (trickling filter, anaerobic, aerated lagoon, rotating biological contactor, and activated sludge), and clarification. A final polishing step using filtration, ozonation, activated carbon, or chemical treatment may also be required.

Liquid effluents should be monitored at least once every eight hours for all the parameters cited above except metals, which should be monitored at least monthly.

Combustion (preceded in some cases by solvent extraction) of toxic organics is considered an effective treatment technology for petrochemical organic wastes. Steam stripping and oxidation are also used for treating organic waste streams. Spent catalysts are generally sent back to the suppliers. In some cases, the solid wastes may require stabilization to reduce the leachability of toxic metals before disposal of in an approved, secure landfill.

Each shipment of solid waste going for disposal should be monitored for toxics

Monitoring data should be analyzed and reviewed at regular intervals and compared with the operating standards so that any necessary corrective actions can be taken. Records of monitoring results should be kept in an acceptable format. The results should be reported to the responsible authorities and relevant parties, as required.

Noise abatement measures should achieve either the levels given below or a maximum increase in background levels of 3 decibels.

Bibliography

1. National Petrochemicals Committee of FICCI – 2012-132. Bat Guidance Note – Diffuse Or Fugitive Emissions , CARDS 2004 project3. Techno-Economic Study On The Reduction Measures, Based On Best Available Technology,

Of Industrial Emissions (Air, Water, Wastes) From The Basic Petrochemical Industry4. Chemical and Petrochemical sector potential of best practice technology and other measures

for improving energy efficiency IEA , information paper. 5. Pollution Prevention and Abatement Handbook, World Bank Group Effective July 19986. Multilateral Investment Guarantee Agency Environmental Guidelines for Petrochemicals

Manufacturing.7. BREF Document

Website

2. http://www.equitymaster.com/research-it/sector-info/petrochem/Petrochemicals-Sector-Analysis-Report.asp

3. http://en.wikipedia.org/wiki/Petrochemical

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