SUB-PROBLEMS INCLUDING LEADING TO IMPAIRMENT AND BEST PRACTICES FOR PRODUCTION OF HAZARDOUS MATERIALS
Companies make basic chemicals by utilizing natural resources such as natural gas, crude oil, minerals, and metals producing both organic and inorganic chemicals, polymers, petrochemicals, dyes and pigments, etc. About 70% of these chemicals are usually sold in large quantities to the chemical industry and are used to create materials for other industries such as the automotive, construction, and packaging sectors.
Petrochemicals can actually be made from coal and biomass as well as crude oil, with methanol as an example, being produced from oil and natural gas in the United States and Europe but from coal in China. Large quantities of ethene are transported in gaseous form through a pipeline in Europe to companies that make polyethene and other polymers. Ammonia is made from natural gases and some of the ammonia is used to make nitric acid. The ammonia and nitric acid are then turned into the fertilizer, ammonium nitrate. Hydrocarbons in crude oil are converted into more useful forms by the chemical industry.
Basic inorganic compounds are used for manufacturing as well as agriculture. They include chlorine, sodium hydroxide, sulfuric acid, nitric acid, hydrochloric acid, and phosphoric acid, and a variety of metals.
This industry has the potential for producing a considerable amount of environmental pollutants in a vast number of areas. The pollutants include:
• Air pollutants, typically nitrogen oxides, sulfur oxides, ammonia, acid mist, carbon monoxide, and carbon dioxide which come from the actual processing of the materials or fugitive emissions, heating devices, pipes with valves, pumps, and compressors, and during the transfer and storage process of raw materials.
• Liquid effluents, typically process and cooling water, stormwater, water from cleaning activities and purges, water from scrubbing gases, water involved in accidental releases or leaks from product storage tanks, condensates, and special effluents depending on the type of manufacturing operation.
• Solid and hazardous waste, which should be kept to an absolute minimum in a well-run and well-managed industrial operation. Typical waste from the manufacturing plants includes: waste oils which can be recycled; used catalysts; wastewater treatment sludge; dust from baghouses used for air pollution control; ash from boilers; and materials from filtration systems.
Best Practices in Control of Production and Use of Basic Chemicals
• Conduct a comprehensive survey of all production, storage, and use of feedstock and basic chemicals to determine potential sources of air pollution, types of releases to the air, and quantities.
• For highly volatile substances, provide a second set of containment vessels to capture release of the substances before the contaminants are released into the air.
• Use good housekeeping practices when transferring products from one system to another or one container to another and clean up all spills immediately.
• Enclose all areas where feedstock is delivered and processed and use either adsorption or absorption techniques in high-efficiency ventilation systems with appropriate bag filters or electrostatic precipitators to trap particulate matter and then pass the air through HEPA filters before allowing it to go to the outside.
• Process all air from energy consumption (this industry uses high levels of energy and therefore produces substantial pollutants) in the same manner as feedstock use stated above.
• Do not use any open vents on tank roofs to prevent escape of fugitive emissions.
• Establish a rigorous maintenance program including use of leak detection devices for all facets of the production and storage program including valves, phalanges, and fittings and carry out necessary work on a routine basis to prevent leakage.
• Use the latest technology and Best Practices and establish a flaring program and record the volumes of gas flared as well as the content. Conduct air pollution surveys downwind from the factory to determine if contaminants are still present in the air after flaring. Wherever possible, try to reuse and recycle the substances instead of burning them off.
• Minimize the use of water in processing and cleaning operations.
• Use primary feedstock with low sulfur content.
• Use closed-loop reactors and evaporators to eliminate process wastewater and to capture chemicals for recycling and reuse.
• Establish a water treatment system to precipitate solids and pretreat effluent to acceptable levels before discharge into other treatment systems.
• Determine if any of the impurities found in the solid and hazardous waste can be put through special reclaiming processes and then can be recycled for further use instead of disposal.
• Determine the impurities and contaminants found in the solid and hazardous waste and ensure that the waste is placed in special landfills which have appropriate linings to prevent leaching to water.