Waste minimization has been proven to be an effective and beneficial operating procedure. You will find that there are many economically and technically feasible waste minimization techniques that can be used in pipeline transportation operations. In fact, many oil and gas operators have implemented waste minimization techniques and have enjoyed benefits such as:
- reduced operating and waste management costs;
- increased revenue;
- reduced regulatory compliance concerns;
- reduced potential liability concerns; and
- improved company image and public relations.
Choosing feasible source reduction and recycling options (i.e., waste minimization) is a smart business decision.
Waste minimization is part of the concept of the "Waste Management Hierarchy." The Waste Management Hierarchy sets out a preferred sequence of waste management options. The first, and most preferred option is source reduction. Source reduction is any activity that reduces or eliminates either the generation of waste at the source or the release of a contaminant from a process. The next preferred option is recycling. Recycling is the reclamation of the useful constituents of a waste for reuse, or the use or reuse of a waste as a substitute for a commercial feedstock or as a feedstock in an industrial process. Together, source reduction and recycling comprise waste minimization. The last two options, and least preferred, of the hierarchy are treatment and disposal.
This document will provide a general overview of waste minimization techniques for wastes arising from pipeline transportation operations. In addition to a discussion of waste minimization techniques for these wastes, the document provides case histories of successful waste minimization projects and a few useful technical references. The references listed in the bibliography provide information regarding useful waste minimization opportunities.
The Railroad Commission also provides the publication Waste Minimization in the Oil Field. Waste Minimization in the Oil Field provides a general overview of waste minimization as a waste management practice and how to include it in an area-specific waste management plan. It also includes chapters on waste generation in oil and gas operations, identification of hazardous oil and gas waste, and the principles of waste minimization.Waste Minimization in the Oil Field is available from the RRC's Waste Minimization Program.
Waste Minimization in Crude Oil and Natural Gas Pipeline Operations
As noted in the introduction, there are many economically and technically feasible waste minimization techniques that may be applied to crude oil and natural gas pipeline operations. The following discussion will consider the various aspects of a pipeline operation and the associated waste streams. Where appropriate, technical references will be cited.
The following will consider various source reduction opportunities for crude oil and natural gas pipeline operations.
Preplanning the siting, construction, operation, and maintenance of pipeline used in crude oil and natural gas pipeline operations is an important time to consider waste minimization techniques. Preplanning the pipeline construction should include consideration of pipeline location and access roads to minimize storm runoff and erosion. If possible the pipeline be located along an existing line to reduce construction of new access roads.
Product substitution is one of the easiest and most effective source reduction opportunities. Vendors are becoming more attuned to operators' needs in this area and are focusing their efforts on providing less toxic, yet effective, substitutes. Some operators, such as the one featured in the case history on page 10, have found that vendors and suppliers will start offering less toxic substitutes in response to a company establishing inventory control procedures. A few examples of effective and beneficial product substitution for crude oil and natural gas pipeline operations are provided below.
- Organic Solvents - Organic solvents, such as trichloroethylene, and carbon tetrachloride, are commonly used for cleaning equipment and tools. These solvents, when spent, become listed hazardous oil and gas wastes and are subject to stringent regulation. Alternative cleaning agents, such as citrus-based cleaning compounds and steam may be substituted for organic solvents. By doing so, a hazardous waste stream may be eliminated, along with the associated waste management and regulatory compliance concerns. Another solvent commonly used is Varsol (also known as petroleum spirits or Stoddard solvent). While most Varsol has a flashpoint below 140oF, which is a characteristically ignitable hazardous wastes when spent, some suppliers may provide a "high flash point Varsol" with a flash point greater than 140oF. Ask for non-toxic cleaners that reduce your regulatory compliance concerns.
- Mechanical Cleaning - Mechanical cleaning techniques are probably the best source reduction methods when using cleaning solvents. There are commercial products which use high pressure and/or high temperature water based solvents to clean equipment. This type of equipment in many cases recycles the cleaning fluid to get the maximum use out of the solvent being used and minimize the volume of the waste generated.
Also, solvents such as xylene and toluene, which may become hazardous wastes, have been commonly used for dissolution and removal of organic deposits (e.g., paraffin). Chemical vendors have access to non-toxic solvents that will substitute for xylene and toluene. Check with your chemical vendor for these substitute solvents before purchasing aromatic solvents such as xylene and toluene.
- Paints and Thinners - Oil-based paints and organic solvents (i.e., thinners and cleaners) are used less frequently today, nonetheless they are still used. These paints and thinners provide an excellent product substitution opportunity. Water-based paints should be used whenever feasible. The use of water-based paints eliminates the need for organic thinners, such as toluene. Organic thinners used for cleaning painting equipment are typically listed hazardous waste when spent. This substitution can eliminate a hazardous waste stream and reduce waste management costs and regulatory compliance concerns.
- Replacing High-Bleed Pneumatics - Many devices used throughout pipeline operations use pneumatic devices such as valves and instruments to control and monitor the flow of gas. These devices need a pneumatic supply to drive their operating mechanisms. The most convenient supply is usually gas in the line the device is monitoring or controlling Many of these devices are high-bleed which use a large volume of gas as a driving mechanism and then vent it to the atmosphere. Replacement with a low bleed device can minimize the amount of gas vented, thus the loss of valuable natural gas. Generally low-bleed devices operate slower than high-bleed devices, and a replacement is not feasible in all cases.
- Replacing Natural Gas with Compressed Air for Operating Pneumatic Devices - Many pneumatic devices in pipelines are controlled by gas in the line. During operation of the devices gas is vented to the atmosphere. Compressed air should be used as the driving force for pneumatic devices when feasible.
- Replacing Reciprocating Engines with Turbines - Turbines are more efficient in their use of natural gas than are reciprocating (e.g., internal combustion) engines. Replacing a reciprocating engine with a turbine unit can reduce the emission of natural gas to the atmosphere. Also, turbines are more efficient than reciprocating engines in driving pumping units. When feasible, consider replacing reciprocating engines with turbines at sites such as compressor stations or pump stations.
- Lubricating Oil Purification Units: - A lube oil testing program combined with extended operating intervals between changes is an effective waste minimization technique, as shown by the case history on page 12. (Even though the case history is from drilling operations, the concept may be applied anywhere.) However, an equipment modification also can effectively reduce the volume of waste lubricating oil and filters. Commercial vendors offer a device called a lube oil purification unit. These units use 1 micron filters and fluid separation chambers and are attached to the lube oil system of an engine. The unit removes particles greater than 1 micron in size and any fuel, coolant, or acids, that may have accumulated in the oil. The unit does not affect the functional additives of the lube oil. The lube oil is circulated out of the system and through the purifier. The purified lube oil is then returned to the engine's lube oil system. Many operators have found that use of lube oil purification units has significantly reduced the need for lube oil changes, waste lube oil management, and concurrently, the cost of replacement lube oil. Also, a new engine that has been fitted with a lube oil purification unit will break in better and operate more efficiently over time, in part because bearing surfaces and piston rings seat better due to the polishing by particles less than 1 micron in size.
- Chemical Metering, or Dosing, Systems - The occasional bulk addition of treating chemicals, such as inhibitors, can result in poor chemical performance and inefficient use of the chemical. A chemical dosing system that meters small amounts of the chemical into a system continuously can reduce chemical usage and improve its performance in the system. In many instances, this equipment modification can result in cost savings due to reduce chemical purchases and more efficient operation of the system.
- Basic Sediment and Water, or Tank Bottoms - Many operators have used simple techniques to minimize the volume of BS&W that accumulates in tanks. Devices such as circulating jets, rotating paddles, and propellers may be installed in crude oil tanks to roll the crude oil so that paraffin and asphaltene remain in solution (or at least suspension). Also, emulsifier can be added to the stock tank to accomplish the same result. Another method used is to circulate the tank bottoms through a heater treater to keep the paraffin and asphaltene in solution.
- Conventional Filters - A good target for waste minimization are the conventional filters that typically comprise a large part of an operation's waste stream. An operator can replace conventional filter units with reusable stainless steel filters or centrifugal filter units (spinners). These devices generate only filtrate as waste and eliminate from the waste stream the conventional filter media and filter body. Operators have found that the reduced costs of replacing lost oil, maintenance requirements, new filter purchases, and waste filter management recover the expense of installing these alternative filtering units.
If conventional filters must be used, an operator should change filters based on differential pressure across the unit. Differential pressure is a good indicator of the effectiveness of a filter unit and can be used to determine the actual need for replacement. This is a simple change that can significantly reduce waste filter generation. The case history provided on page 11 proves this point.
Reduction in Water Use
Large amounts of water are used when hydrotesting lines. To reduce water use and water disposal costs operators should, when feasible, reuse hydrotest water to test as many lines as possible. In some instances, reuse of hydrotest water can result in the reduction of significant waste management costs and water purchase costs.
Also, some pipeline operators have found the use of ultrasonic ("smart") pigs may reduce the need for hydrotesting. Smart pigs can assess the condition of pipe and, thus, may help in more efficient planning of hydrotesting.
Good Housekeeping and Preventative Maintenance
- Drip Pans and Other Types of Containment - Tanks, containers, pumps, and engines all have the tendency to leak. A good housekeeping practice that can help reduce the amount of soil and water contamination that an operator has to remediate is installing containment devices. Even though a small investment is required, containment devices save money and regulatory compliance concerns in the long run. Also, they can capture valuable released chemicals that can be recovered and used. Some examples of containment include: drip pans beneath lubricating oil systems on engines; containment vessels beneath fuel and chemical storage tanks/containers; drip pans beneath the drum and container storage area; and containment, such as a half-drum or bucket beneath chemical pumps and system valves/connections. Numerous companies have implemented good housekeeping programs to reduce the amount of crude oil, chemicals, products, and wastes that reach the soil or water. These companies have found these programs to be cost effective in the long run (i.e., less lost chemical and product plus reduced cleanup costs). Also, their regulatory compliance concerns and potential future liability concerns are reduced.
- Preventive Maintenance - The companion of good housekeeping is preventive maintenance. Regularly scheduled preventive maintenance on equipment, pumps, piping systems and valves, and engines will minimize the occurrence of leaks and releases of chemicals and other materials to containment systems, or if there are no containment systems, to the environment. Numerous companies have implemented preventive maintenance programs and found them to be quite successful. The programs have resulted in more efficient operations, reduced regulatory compliance concerns, reduced waste management costs, and reduced soil and/or ground water cleanup costs.
- Chemical and Materials Storage - Another important aspect of good housekeeping is the proper storage of chemicals and materials. Chemicals and materials should be stored such that they are not in contact with the ground (e.g., on wooden pallets). Preferably, the raised storage area will include secondary containment and be protected from weather. All drums and containers should be kept closed except when in use. It is very important that all chemical and material containers always be properly labeled so that their contents may be identified at any time. Also, material data safety sheets (MSDSs) and other manufacturer information should be kept on file for all stored chemicals and materials. The use of bulk storage, rather than 55-gallon drums or smaller containers is a preferable way to store chemicals and materials. Proper storage and labeling of containers allows quick and easy identification and classification of released chemical or material in the event of a leak or rupture. In some instances, that could save hundreds of dollars in soil sampling and laboratory analysis costs.
Inventory control is one of the most effective ways to reduce waste generation, regulatory compliance concerns and operating costs. Especially, when combined with proper chemical and materials storage. The case history on page 10 illustrates the beneficial impact an inventory control system can have on an operation. An inventory control system is easy to implement, especially with the use of computer programs now available. An operator who tracks his chemicals and materials can use them more efficiently and reduce the volume of unusable chemical that must be managed as waste. (Note: Commercial chemical products that are returned to a vendor or manufacturer for reclamation or recycling are not solid wastes. Therefore, it is to the operator's advantage to require vendors to take back empty and partially filled containers for reclamation or reuse.)
Selection of Contractors
Operators should choose contractors who recognize the value of waste minimization and make efforts to apply it in their service. The operator may consider inspecting the contractors equipment being considered for contract to appraise the general condition of the equipment. The contractor should bring on-site well maintained equipment that will not leak fuel or lubricating oil or that will need maintenance which may generate wastes. Any oil and gas waste generated at the operator's site is the operator's regulatory responsibility. Therefore, an operator that uses contractors who practice waste minimization can expect reduced waste management concerns, reduced regulatory compliance concerns, and reduced operating costs. The contractor may be instrumental in implementing the waste minimization opportunities discussed above.
The next preferred waste management option is recycling. Recycling is becoming a big business and more recycling options are available every day The following discussion offers some tips on recycling drilling wastes.
- Tank Bottoms - If nonhazardous, tank bottoms, or BS&W, are best managed by sending them to a crude oil reclamation plant. An operator should contact nearby RRC-permitted crude oil reclamation plants to determine if an economically feasible arrangement is possible before considering disposal options. The Waste Minimization Program can help operators locate reclamation plants in their area. Many of these plants also specialize in reclamation of waste paraffin.
- Lubricating Oil and Filters - Currently, waste lube oil and waste lube oil filters are generally banned from landfill disposal. Recycling is now the primary method of managing these wastes. Companies that handle lube oil and filters for recycling are located in every area of Texas, so finding one is not difficult. The Waste Minimization Program will provide upon request a listing of these companies.
Also, an operator can recycle his waste lube oil by adding it to a crude oil pipeline or storage tank. Amendments to 40 CFR (Code of Federal Regulations) Part 279 (regarding standards for management of lubricating oil) provide for this option. There is a regulatory limit of 1% lube oil by volume. An important consideration in choosing this recycling option is the requirements of the crude oil purchaser and the receiving refinery. Make sure they will accept a crude oil and lube oil mixture. (Some refineries are not able to handle such mixtures, and suffer damage to catalysts and other processes.)
- Compressor Lubricating Oil - One inventive operator devised a procedure to optimize the use of lubricating oils in compressor units. According to the operator, used lubricating oil from the drive engine was of adequate quality to serve as lube oil in the compressor. So, the operator established a procedure where the used lube oil from the drive engine would be recovered and directed to the compressor. The result of this reuse option was reduced waste lube oil generation and reduced new lube oil purchases, making this a cost-effective waste minimization technique.
- Sorbent Pads and Booms - When cleaning up spills of crude oil and chemicals, use recyclable sorbent pads or booms. Try to avoid using granular adsorbent materials that must be disposed of. Several vendors offer sorbent pads and booms that are designed for repeated reuse.
- Spent organic solvents and other miscellaneous spent chemicals: Many companies accept spent chemicals for recycling. In many instances the spent chemicals (especially organic solvents) are reclaimed for reuse or blended to make fuels for energy recovery. See "Recycling Information" below to learn how to find these companies.
- Paint Solvent Reuse - A simple technique for reducing the volume of organic paint solvents is its reuse in stages. An organic solvent, such as toluene, may be used for cleaning painting equipment, but eventually it will become spent and ineffective. The "spent" solvent is not a waste if it is used for another intended purpose. A solvent spent from cleaning painting equipment is still suitable for use in thinning paint. This simple technique can greatly reduce the volume of waste paint solvent that may be subject to stringent hazardous waste regulation.
- Commercial Chemical Products - An operator should implement procedures that recycle any unused chemical products. Whenever a vendor is contracted to supply chemicals, the vendor should be required to take contractual responsibility for unused chemical products and the containers in which they were delivered. As noted under the source reduction opportunity, "Inventory Control," commercial chemical products that are returned for reclamation or recycling are not solid wastes. An operator that manages chemical products properly will avoid the unnecessary generation of chemical waste. In many, instances those chemical wastes would be hazardous and subject to stringent regulation.
- Scrap Metal and Drums - Scrap metal is a relatively easy waste to recycle. Many operators have found that scrap metal recycling companies will collect and remove materials such as tanks, drums, and other types of scrap metal from the lease at no charge to the operator. An additional consideration is regulatory requirements. Scrap metal that is recycled is not subject to hazardous oil and gas waste regulations; but it is if disposed of. For example, an old steel tank coated with lead-based paint would likely be determined hazardous if disposed of; however, if recycled it is excluded from regulation as a hazardous oil and gas waste.
An excellent way to ensure that steel 55-gallon drums are recycled is to have in the contract with a vendor the requirement that the vendor take back any delivered drum, including drums that still contain some chemical or product. Note that empty drums and commercial chemical product that is recycled are generally excluded from regulation as hazardous oil and gas waste. (Also, see the discussions in "Good Housekeeping" and "Inventory Control.")
The RRC's Waste Minimization Program can help operators identify recycling options. More information on Waste Minimization Program assistance is presented on page 13. The Texas Commission on Environmental Quality (TCEQ) publishes two useful documents: Recycle Texas and RENEW.Recycle Texas is a listing of many of the companies that take various wastes for recycling. Those wastes include many that are typical of oil and gas operations. RENEW is a waste exchange that is published quarterly. RENEW lists companies that have generated wastes and are making them available for recycling, and RENEW also lists companies that want certain wastes for recycling. Recycle Texas and RENEW are available free of charge from TCEQ and can be obtained by calling 1-800-648-3927.
Training is probably one of the best waste minimization opportunities. An operator's efforts to minimize waste and gain the associated benefits will only be effective if the people in the field understand waste classification and the concept of waste minimization. Also, people in the field should be empowered to implement waste minimization techniques as they are identified. Waste minimization training is becoming more common. Oil and gas associations have begun publicizing waste minimization successes, and technical societies such as the SPE, are publishing more and more papers on effective waste minimization techniques.
Waste Minimization in the Oil Field Manual
Waste Minimization in the Oil Field: This manual, developed with the assistance of the oil and gas industry, offers source reduction and recycling (i.e., waste minimization) concepts, cost effective and practical examples of source reduction and recycling opportunities in the oil field, and information on how to develop an individualized waste minimization plan. The manual also presents a discussion on how to identify hazardous and nonhazardous oil and gas wastes as defined by EPA regulations under the Resource Conservation and Recovery Act.
EPA's Natural Gas Star Program
An additional source for waste minimization techniques in natural gas pipeline operations is the EPA Natural Gas STAR Program. The Natural Gas STAR Program is a voluntary government/industry partnership designed to accomplish environmental protection through cost-effective measures without regulation. The program was started in March of 1993 and it encourages natural gas companies to adopt "best management practices" that can reduce methane emissions.
Natural Gas STAR Partners sign a Memorandum of Understanding (MOU) with EPA agreeing to review and implement "best management practices" as appropriate. The company then implements the plan over the next three years. The EPA supports the partners by assisting in training, analyzing new technologies, and removing unjustified regulatory barriers.
More information on the Natural Gas Star Program can be obtain by contacting Rhone Resch at (202) 233-9793, e-mail firstname.lastname@example.org
U.S. EPA Natural Gas Star Program
U.S. EPA APPD (6202J)
Washington, DC 20460
SPE Technical Papers
Santamaria, et al, "Controlling Paraffin Deposition Related Problems by the Use of Bacteria Treatments", Society of Petroleum Engineers 22851 (October 1991)
Whale & Whitman, "Methods for Assessing Pipeline Corrosion Prevention Chemicals on the Basis of Antimicrobial Performance and Acute Toxicity to Marine Organisms", Society of Petroleum Engineers 23357 (November 1991)
Wilhelm & McArthur, "Removal and Treatment of Mercury Contamination at Gas Processing Facilities", Society of Petroleum Engineers 29721 (March 1995)