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Multilateral Investment Guarantee Agency

Environmental Guidelines for Petrochemicals

Industry Description and Practices are available to manufacture the desired products. (Further details of typical processes and crude distillates such as and products are provided in the annex.) (from refining) are used as feedstocks to manufacture a wide variety of Waste Characteristics petrochemicals which are in turn used for the manufacture of a variety of consumer goods. Fugitive air emissions from pumps, valves, The description of petrochemical processes and flanges, storage tanks, loading and unloading products presented here is for illustrative operations, and wastewater treatment are of purposes only. The basic petrochemicals greatest concern. Some of the compounds manufactured by , reforming, and released to air are carcinogenic or toxic. other processes include olefins (including and propylene emissions are of ethylene, propylene, butylenes, and ) concern because of their fate processes which and aromatics (including , , and lead to the formation of oxides which are ). The capacity of naphtha crackers is extremely toxic. Compounds considered generally of the order of 250,000 to 750,000 carcinogenic that may be present in air metric tons per year (tpy) of ethylene emissions include benzene, butadiene, 1,2- production. Some petrochemical plants also dichloroethane, and . A typical have and oxo-compounds naphtha cracker at a petrochemical complex manufacturing units on-site. The base may annually release about 2,500 emetric tons petrochemicals or products derived from them of (such as propylenes and ethylene), along with other raw materials are converted when producing 500,000 metric tons of to a wide range of products including ethylene. Boilers, process heaters, flares, and and (such as low density other process equipment (in some cases may (LDPE), high density polyethylene (HDPE), include catalyst regenerators)are responsible linear low density polyethylene (LLDPE), for the emission of particulates, , , and polyvinyl monoxide, nitrogen oxides (200 metric tons per chloride (PVC)); synthetic (such as year), and sulfur oxides (SOx) (600 metric tons and acrylic); per year based on a 500,000 metric tons per (such as butadiene (ABS)); year of ethylene capacity). rubbers (including styrene butadiene rubber The release of volatile organic compounds (SBR) and (PBR)); ; (VOCs) to air depends on the products handled industrial chemicals (including those used for at the plant and may include acetaldehyde, the manufacture of such as linear , benzene, toluene, , alkyl benzene (LAB), , dyestuff, trichlorotoluene, and . VOC emissions agrochemicals, pharmaceuticals, and are mostly fugitive and depend upon the explosives). A number of alternative methods production processes, material handling and

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effluent treatment procedures, equipment environmental hazard releasing large maintenance, and climatic conditions. VOC quantities of pollutants and products into the emissions from a naphtha cracker range from environment. Plant safety and fire prevention and 0.6 to 10 kilograms (kg) (75% are , 20% control procedures should be in place. unsaturated hydrocarbons about half of these is ethylene, and remaining 5% are aromatics) Prevention and Control per metric ton of ethylene; 0.02 to 2.5 kg (45% of these being ethylene dichloride, 20% being Petrochemical plants are typically large and vinyl chloride, and 15% being chlorinated complex, where the combination and sequence organics) per metric ton of product in a vinyl of processes is usually very specific to the chloride plant; 3-10 kg per metric ton of characteristics of the products manufactured. product in a SBR plant; 0.1-2 kg per metric ton Specific pollution prevention or source of product in ethyl benzene plant; 1.4-27 kg per reduction measures are best determined by metric ton of product in ABS plant; 0.25-18 kg technical staff. However, there are a number of per metric ton of product in a styrene plant; broad areas where improvements are often and 0.2-5 kg per metric ton of product in a possible and site specific emission reduction polystyrene plant. measures in these areas should be designed Petrochemical units generate wastewaters into the plant and targeted by plant from process operations (such as vapor management. condensation), blow down, and Areas where effort should be concentrated storm run off. Process wastewaters are include: generated at a rate of about 15 cubic meters per 3 hour (m /hr) (based on a 500,000 metric tons Reduction of Air Emissions per year ethylene production) and may contain biochemical demand (BOD ) (100 5 • Minimize the leakages of volatile organics mg/L), COD (1,500-6,000 mg/L), suspended (including benzene, vinyl chloride, and solids (100-400 mg/L), and and grease (30- ) from valves, pump glands (use 600 mg/L). levels of up to 200 mg/L mechanical seals), flanges, and other process and benzene levels of up to 100 mg/L may also equipment by following good design practices be present. and equipment maintenance procedures. Petrochemical plants also generate solid • Use mechanical seals, where appropriate. wastes and sludges, some of which may be • Minimize losses from storage tanks, considered hazardous because of the presence product transfer areas, and other process areas of toxic organics and heavy metals. Spent by adopting methods such as vapor recovery caustic and other hazardous wastes such as systems and double seals (for floating roof residues associated with units tanks). handling acetaldehyde, acetonitrile, benzyl • Recover catalysts and reduce particulate chloride, carbon tetrachloride, , emissions. phthallic anhydride, , methyl • Use low NO burners to reduce NO ethyl pyridine, , x x emissions. trichloroethane, trichloroethylene, • Optimize fuel usage. perchloroethylene, , , • In some case, organics that cannot be dimethyl hydrazine, ethylene dibromide, recovered, are effectively destroyed by routing toluenediamine, , ethyl them to flares and other combustion devices. chloride, ethylene dichloride, and vinyl chloride may be generated in significant Elimination/Reduction of Pollutants quantities. Accidental discharges as a result of • Use non-chrome based additives in abnormal operation especially from cooling water. polyethylene and ethylene-oxide-glycol plants • Use long life catalysts and regeneration to in a petrochemical complex can be a major extend the cycle.

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Recycling/Reuse Treatment Technologies

• Recycle cooling water and treated Air Emissions wastewater to the extent feasible. • Recover and re-use spent solvents and Control of air emissions normally includes the other chemicals to the extent feasible. capturing and recycling or combustion of emissions from vents, product transfer points, Improved Operating Procedures storage tanks, and other handling equipment. Catalytic cracking units should be provided • Segregate process wastewaters from with particulate removal devices. Particulate stormwater systems. removal technologies include fabric filters, • Optimize tank and equipment cleaning ceramic filters, wet scrubbers, and electrostatic frequency. precipitators. Gaseous releases are minimized • Prevent solids and oily wastes from by condensation, absorption, adsorption entering the drainage system. (activated carbon, silica gel, activated alumina, • Establish and maintain an Emergency and zeolites), and in some cases using Preparedness and Response Plan. biofiltration and bioscrubbing (using peat/heather, bark, composts, and bioflora for Target Pollution Loads treating biodegradable organics), and thermal decomposition. Implementation of cleaner production processes and pollution prevention measures Liquid Effluents can provide both economic and environmental benefits. The following production-related Petrochemical wastewaters often require a targets can be achieved by measures such as combination of treatment methods to remove those detailed in the previous section. The oil and other contaminants before discharge. figures relate to the production processes Separation of different streams (such as before the addition of pollution control stormwater) is essential to minimize treatment measures. requirements. Oil is recovered using separation A good practice target for petrochemical techniques. For heavy metals, a combination of complex is that the total organic emissions oxidation/reduction, precipitation, and (including VOCs) from the process units be filtration is used. For organics, a combination reduced to 0.6% of the throughput. Target of air or steam stripping, granular activated maximum levels for air releases of ethylene, carbon, wet oxidation, ion exchange, reverse ethylene oxide, vinyl chloride, and 1,2- osmosis, and electrodialysis is used. A typical dichloroethane are 0.06 kg, 0.02 kg, 0.2 kg, and system may include neutralization, 0.4 kg per ton of product. Methods of coagulation/flocculation, estimating these figures include ambient and flotation/sedimentation/filtration, emissions monitoring, emission factors, and biodegradation (trickling filter, anaerobic, inventories of emissions sources. Design aerated lagoon, rotating biological contactor, assumptions should be recorded to allow for and activated sludge), and clarification. A final subsequent computation and reduction of polishing step using filtration, ozonation, losses. activated carbon, or chemical treatment may Vapor recovery systems to control losses of also be required. Pollutants loads which can be VOCs from storage tanks and loading areas achieved include a COD level of less than 1 kg, should achieve close to 100% recovery. suspended solids level of less than 0.4 kg, and A wastewater generation rate 15 m3 per 100 dichloroethane level of less than 0.001 kg, per tons of ethylene produced is achievable with 100 tons of ethylene produced. good design and operation and new petrochemicals should strive to achieve this.

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Solid and Hazardous Wastes Emissions from Petrochemicals Manufacturing and Target Ambient Levelsi1 2 Combustion (preceded in some cases by Parameter Maximum value extraction) of toxic organics is milligrams per normal considered an effective treatment technology cubic meter(mg/Nm3) for petrochemical organic wastes. Steam stripping and oxidation are also used for Particulate matter 20 treating organic waste streams. Spent catalysts (PM) are generally sent back to the suppliers. In Nitrogen oxide (NOx) 300 some cases, the solid wastes may require chloride 10 stabilization to reduce the leachability of toxic Sulfur oxide (SOx) 500 metals before disposal in an approved secure Benzene 5 mg/m3 for landfill. emissions; 0.1 ppb at Emission Guidelines the plant fence 1,2-dichloroethane 5 mg/m3 for Emission levels for the design and operation of emissions; 1.0 ppb at each project must be established through the the plant fence Environmental Assessment (EA) process, based Vinyl chloride 5 mg/m3 on country legislation and the Pollution for emissions; 0.4 Prevention and Abatement Handbook as applied ppb at the plant to local conditions. The emission levels selected fence must be justified in the EA and acceptable to 15 mg/m3 MIGA. 1Maximum ambient levels for ethylene oxide are 0.3 ppb at the The following guidelines present emission plant fence. 1 levels normally acceptable to the World Bank Maximum VOC emissions total of acetaldehyde, , Group in making decisions regarding benzyl chloride, carbon tetrachloride, chlorofluorocarbons, ethyl provision of World Bank Group assistance, acrylate, halons, maleic anhydride, 1, 1, 1 trichlorethane, trichloroethylene, and trichlorotoluene) should be 20 mg/Nm3. including MIGA guarantees; any deviations Total heavy metals should be 1.5 mg/Nm3. from these levels must be described in the project documentation. Liquid Effluents The guidelines are expressed as concentrations to facilitate monitoring. The following effluent levels should be Dilution of air emissions or effluents to achieve achieved: these guidelines is unacceptable. All of the maximum levels should be Effluents from Petrochemicals Manufacturing achieved for at least 95% of the time that the Parameter Maximum value plant or unit is operating, to be calculated as a milligrams per liter proportion of annual operating hours. (mg/L) pH 6 – 9 Air Emissions BOD5 30 The following emissions levels should be COD 150 achieved: Total suspended solids 30 Oil and grease 10 Cadmium 0.1

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Effluents from Petrochemicals Manufacturing (cont’d) The emission requirements given here can Chromium (hexavalent) 0.1 be consistently achieved by well-designed, Copper 0.5 well-operated and well-maintained pollution Phenol 0.5 control systems.

Benzene 0.05 Monitoring and Reporting Vinyl chloride 0.05 Sulfide 1 Frequent sampling may be required during start-up and upset conditions. Once a record of Nitrogen (total) 10 consistent performance has been established, Temperature increase less than or equal sampling for the parameters listed above to 3°C1 should be as detailed below. 1 The effluent should result in a temperature increase of no Air emissions from stacks should be more than 3 degrees Celsius at the edge of the zone where visually monitored for opacity at least once initial mixing and dilution takes place. Where the zone is not every eight hours. Annual emissions defined, use 100 meters from the point of discharge. monitoring of combustion sources should be carried out for SOx ,NOx , and organics listed Note: Effluent requirements are for direct above with fuel sulfur content and excess discharge to surface . oxygen maintained at acceptable levels during normal operations. Leakages should be Solid Wastes and Sludges visually checked every eight hours and at least once a week using leak detection equipment. Wherever possible, generation of sludges Liquid effluents should be monitored at should be minimized. Sludges must be treated least once every 8 hours for all the parameters to reduce toxic organics to non-detect levels. cited above except for metals which should be Wastes containing toxic metals should be monitored on at least a monthly basis. stabilized before disposal. Each shipment of solid waste going for The emission guidelines given here can be disposal should be monitored for toxics. consistently achieved by well-designed, well- Monitoring data should be analyzed and operated and well-maintained pollution reviewed at regular intervals and compared control systems. with the operating standards so that any necessary corrective actions can be taken. Ambient Noise Records of monitoring results should be kept in an acceptable format. These should be reported Noise abatement measures should achieve to the responsible authorities and relevant either the following levels or a maximum parties, as required, and provided to MIGA if increase in background levels of 3 dB(A). requested. Measurements are to be taken at noise receptors located outside the project property Key Issues boundary. The following box summarizes the key Ambient Noise production and control practices that will lead Maximum Allowable Leq (hourly), to compliance with emission guidelines: in dB(A) Daytime Nighttime • Implement an equipment maintenance Receptor 07:00 - 22:00 22:00 - 07:00 program which minimizes releases of volatile organics including ethylene oxide, Residential; 55 45 institutional; benzene, vinyl chloride, 1,2-dichloroethane, educational and other organics. Industrial; 70 70 • Install vapor recovery systems to reduce commercial VOC emissions.

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• Use low NOx burners. Consultation on Downstream Petrochemical Industries in Developing Countries in Tehran, • Optimize fuel usage. Islamic Republic of Iran during November 7 • Regenerate and reuse spent catalysts, through 11, 1993. solvents, and other spent solutions to the extent feasible. The World Bank. 1990. The Petrochemicals in Developing , A Review of the • Recycle cooling water and reuse Current Situation and Prospects for wastewaters. Development in the 1990s by Walter Vergara • Segregate storm water from process and Dominique Babelon. World Bank wastewater. Technical Paper Number 113, Industry and Energy Series. Washington, DC. • Use non-chrome based additives in cooling water. The World Bank. 1988. The New Face of the • Design and practice emergency World Petrochemical Sector, Implications for preparedness and prevention measures. Developing Countries by Walter Vergara and Donald Brown. World Bank Technical Paper Further Information Number 84, Industry and Energy Series, Washington, DC. The following are suggested as sources of additional information (these sources are provided for guidance and are not intended to be comprehensive):

Bounicore and Davis. 1992. Air Pollution Engineering Manual. New York: Van Nostrand Reinhold Publications.

Cortes, M. and Peter Bocock. 1984. North-South Technology Transfer, A Case Study of Petrochemicals in Latin America. Published for The World Bank by The John Hopkins University Press, Baltimore, Maryland.

The Economist Intelligence Unit. 1991. Petrochemicals - An Industry and Its Future by Roger Langley. Special Report No. 2067.

Her Majesty’s Inspectorate of Pollution. 1993. Chief Inspector’s Guidance to Inspectors, Environmental Protection Act 1990, Process Guidance Note IPR 4/1, Petrochemical Processes.

National Swedish Environmental Protection Board. 1987. Focus on Environmental Impacts of Petrochemical Plants in Stenungsund. SNV Report Number 3209.

The United Nations Industrial Development Organization (UNIDO). 1994. Report on

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ANNEX: Typical Processes and xylene, and in some cases, naphthalene. Other Products aromatics manufactured include phenol, , styrene, phthalic and maleic C1 compounds (having one carbon atom in anhydride, nitrobenzene, and aniline. Benzene their molecule) manufactured at petrochemical is generally recovered from cracker streams at plants include , , and petrochemical plants and is used for the halogenated hydrocarbons. Formaldehyde is manufacture of phenol, styrene, aniline, used for the manufacture of (including nitrobenzene, sulfonated detergents, pesticides phenolic, , and melamine) resins. (such as hexachlorobenzene), (an Halogenated hydrocarbons are used for the important intermediate in synthetic manufacture of silicone, solvents, refrigerants manufacture), and caprolactum (used in the and degreasing agents. manufacture of ). Benzene is also used as Olefins (organics having at least one double a solvent. bond for carbon atoms) are typically Major uses of toluene are as solvent in manufactured from the of , rubber, and plastic cements, as hydrocarbons such as naphtha. Major olefins feedstock for the manufacture of organic manufactured include ethylene (C2, since it has chemicals, explosives, detergents, and two carbon atoms), propylene (C3, since it has foams. Xylenes (exist as three three carbon atoms), butadiene, (C4, since it has ) are used for the manufacture of four carbon atoms) and in some cases, dimethyl terphthalate (feedstock for the acetylene. The olefins manufactured are used manufacture of polyester), resins, and for the manufacture of polyethylene (including plasticizers. Naphthalene is mainly used for low density polyethylene (LDPE) and high the manufacture of , pharmaceuticals, density polyethylene (HDPE)), polystyrene, insect repellents, and (used , (used along for the manufacture of alkyd resins, with dimethyl terphthalate (DMT) as feedstock plasticizers, and polyester). to the polyester manufacturing process), The largest user of phenol in the form of (used as solvents), polyvinyl thermosetting resins is the plastic industry. acetate (used in plastics), polyisoprene (used Phenol is also used as a solvent and for the for manufacture), manufacture of intermediates for pesticides, polypropylene, acetone (used as solvent and in pharmaceuticals, and dyestuff. Styrene is used ), isopropanol (used as solvent and in for the manufacture of synthetic rubber and pharmaceuticals manufacturing), acrylonitrile polystyrene resins. Phthalic anhydride is used (for the manufacture of acrylic fibers and nitrile for the manufacture of dimethyl terphthalate, rubber), (used in alkyd resins and plasticizers such as pharmaceuticals manufacturing), and phthalates. Maleic anhydride is used for the polyurethane. manufacture of and to some extent Butadiene is used in the manufacture of for alkyd resins. Minor uses include the polybutadiene rubber (PBR) and styrene manufacture of malathion and soil butadiene rubber (SBR). Other C4 compounds conditioners. Nitrobenzene is used for the (having four carbon atoms) manufactured manufacture of aniline, benzidine, dyestuff, include butanol (used for the manufacture of and as solvent in polishes. Aniline is used in solvents such as methyl ethyl ketone). the manufacture of dyes (including azo dyes) The major aromatics (organics with at least and rubber chemicals (such as vulcanization one ring structure with six carbon atoms) accelerators and antioxidants). manufactured include benzene, toluene,

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