Fall 2005
Issue Focus: Identifying Opportunities for Waste Heat Reduction
This page presents all the articles in the Fall 2005 issue of Energy Matters, the BestPractices quarterly of the U.S. Department of Energy's Industrial Technologies Program.
In This Issue
- Identifying Opportunities for Waste Heat Reduction
- Compressed Air System Upgrade Increases Efficiency and Saves Energy at a Newspaper Plant
- Identifying Ways to Decrease Waste Provides Opportunities to Improve Resource Utilization, Conserve Energy, and Save Money
Identifying Opportunities for Waste Heat Reduction
The Texas Pilot Project Tests for Success
Freescale Semiconductor staff used the pumping system assessment standard to evaluate the energy efficiency of the chilled water system at the company's Oak Hill plant.
There is no substitute for experience. With that in mind, five manufacturing plants in Texas volunteered to test the elements of the proposed Superior Energy Performance program to help pave the way for its success across the nation. This article chronicles the progress of the pilot project and describes individual plant experiences, lessons learned, and next steps.
The Superior Energy Performance voluntary plant certification program seeks to improve U.S. industrial energy efficiency by making energy management an essential part of a company's standard operating procedure. To help companies focus on energy efficiency goals, the program offers a framework of energy management system implementation and documented energy intensity improvements. Other tools being tested to support this framework include four energy system assessment standards and a measurement and verification (M&V) protocol.
Testing the elements of the program in operating manufacturing plants provides invaluable experience to gauge how effective this program will be for other plants. And so, the Texas pilot project was launched in 2008 to assess the practical application of Superior Energy Performance, a program that could have Texas-sized energy-saving potential for the nation.
The Texas Industries of the Future is coordinating the pilot plant project, with support from the U.S. Department of Energy (DOE) Industrial Technologies Program and the Texas State Energy Conservation Office. The Georgia Institute of Technology conducted training on implementation of the energy management standard while Lawrence Berkeley National Laboratory and Oak Ridge National Laboratory assisted with development of the M&V protocol and system assessment standards. The U.S. Council for Energy-Efficient Manufacturing, an industry-led initiative, provides oversight and guidance of the program.
Testing for Real-World Results
The goal of the pilot project is to verify that the processes, standards, and performance criteria of the Superior Energy Performance program are practical and achievable, benefit the participating plants, and reliably identify plants that meet the proposed certification criteria.
Testing the criteria with plants of various sizes and energy management experience ensures that the program offers value and flexibility to a variety of companies. The test plants represent a variety of industries—food processing, insulation, semiconductors, and chemicals—and characterize small, medium, and large industrial plants ranging in sizes from 50 to 2,700 employees. They include:
- Cook Composites and Polymers, Houston plant
- Freescale Semiconductor, Inc., Oak Hill plant
- Frito-Lay, San Antonio plant
- Owens Corning, Waxahachie plant
- Union Carbide (a subsidiary of Dow Chemical Company), Texas City plant.
Kathey Ferland, Project Lead for Texas Industries of the Future, knows the importance of the pilot project in testing the processes and standards of the Superior Energy Performance program.
"Launching a program like this requires resources from both the public and private sector. We needed a real-world test of the value and resources necessary to apply the energy management and system assessment standards and evaluate the plants' energy performance and program criteria," explains Ferland. "The pilot plant project is providing good data on the costs and benefits of the program, as well as honest feedback from participants about what works or needs revision."
The pilot program will continue until spring 2010 to maximize the value from the testing. These plants could become the first in the nation to become certified in energy efficiency.
Diverse Plants Working Toward a Common Cause
To provide a thorough test of the program elements, developers selected plants from a variety of industry types, sizes, and levels of energy management experience. The criteria for plant selection included:
- Company management committed to energy efficiency and implementing an energy management system
- At least two energy systems (compressed air, process heating, pumps, or steam) to evaluate for energy-saving opportunities
- A metering system in place to provide an energy-use baseline by which to measure savings.
In general, each of the selected plants uses a significant amount of energy. Four of five plants have International Organization for Standardization (ISO) 9001 and/or ISO 14001 management systems in place, and some plants have created internal systems incorporating health, safety, and environmental requirements. All but one of the plants has been implementing energy efficiency projects and planning for many years. Two of the facilities' parent companies have been recognized as EPA ENERGY STAR® Partners of the Year.
Based on unique organizational structures, philosophies, and management system expertise, each plant has developed its own distinct implementation strategy, which provides an invaluable contribution to the development of the Superior Energy Performance program.
"The initial CCP energy management team consists of a small, cross-functional group of employees working remotely from four different sites (Virginia, Missouri, Michigan, and Houston) with the common goal of achieving MSE certification first at the Houston location. CCP considers the ANSI/MSE standard to be an essential energy management component to its existing integrated management system in order to achieve additional economic, environmental, and societal benefits. Participation in the Texas Pilot Program has enabled us to gain valuable experience by sharing information and ideas with other companies who have managed energy for varying lengths of time and on a much larger scale."
Deborah Magoon, Director, Integrated Management Systems
Cook Composites and Polymers Co. (CCP): CCP, a synthetic resin manufacturing plant in Houston, began participating in the Texas pilot plant project in 2008 with high expectations. The plant's energy costs had increased dramatically since 1998, amounting to 20% of the plant's operating budget by 2008. Company management was very convinced of the value of taking a management system approach to energy because of the improvements they had seen in their safety record and property losses after management system implementation in those areas. DOE Energy Experts tested the proposed system assessment standards for steam and process heating systems, and identified opportunities that could save 30% of those systems' natural gas use.
CCP already had a robust, integrated health, safety, quality, and environmental management system in place, and is in the process of incorporating the energy management components into this existing structure. The CCP pilot project team is working to implement a management system for energy throughout the company.
"The pilot program provided an opportunity to integrate our energy conservation efforts into a comprehensive energy management system. It led us to review the plant operating procedures, which we modified to emphasize energy efficiency. We have developed key performance indicators and control charts at the system level to understand how various factors impact our energy use. These tools are now used to drive continuous improvement in energy efficiency by evaluating the effectiveness of energy conservation projects and monitoring to ensure that improvements are sustainable."
Mark Krawczyk, Plant Services Engineer
Freescale Semiconductor, Inc.: Freescale is a global leader in the design and manufacture of embedded semiconductors for the automotive, consumer, industrial, and networking markets. The company's Oak Hill plant consumes 210 million kWh of electricity and 0.22 trillion Btu of natural gas annually.
The Freescale pilot project is a good example of how a company can leverage plant-level activities into a corporate-wide energy management program. When Freescale began the pilot program, the company already had ISO 9001 and 14001 certification in place; they elected to add their energy management system to the existing environmental management system. Furthermore, Freescale is implementing the energy management program at a sister facility also located in Austin.
As a result of applying the assessment standards to the compressed air and pumping systems, the DOE Energy Experts worked with plant staff to identify energy saving opportunities of 0.4 million kWh and 1.1 million kWh, respectively, and found ways to enhance reliability of the compressed air system. M&V of energy performance will be conducted in early 2010.
"The Texas Pilot Program has provided an avenue to verify the benefits and opportunities of our current energy management system. Having a third party assess our plant enabled us to identify areas of possible improvement to our current system and provided ideas for implementation of new technology that may be a potential fit with our system. The pilot program also allowed us to share energy management systems best practices with other industry partners."
Matt Taylor, Project Engineer
Frito-Lay: Frito-Lay's mission to make the best snacks on earth while protecting the planet includes using energy-efficient practices in its manufacturing plants and setting long-term corporate energy-reduction goals. The Frito-Lay plant in San Antonio produces more than 50 million pounds of snack food annually, and employs approximately 250 workers.
During the field test, Frito-Lay implemented the requirements of ANSI/MSE 2000-2008 into its existing management program, and plans to share best practices identified in the test project with other Frito-Lay plants. Plant managers volunteered the site for compressed air and process heating system assessments, which identified energy-saving opportunities of 51% and 5% respectively. Energy intensity improvements will be measured and verified in early 2010.
"The Texas Pilot Program has connected us with other manufacturers and allowed us to compare energy management best practices. Our involvement with this program has caused us to formalize or create procedures that will help us sustain our energy management results. An important part of this program helps us develop an energy management system that becomes part of our standard work, instead of relying on one or two key people who drive energy awareness. We have chosen to tie this into our existing Operations Management System. In our case, this becomes part of our ISO processes."
Glenn Haley, Plant Leader
Owens Corning: Although Owens Corning insulation products are designed to save energy, manufacturing them is an energy-intensive process. The Owens Corning plant in Waxahachie has three manufacturing lines to produce building and loosefill insulation, which costs the company approximately $20 million in annual energy use.
Owens Corning has a very proactive energy management program and is incorporating the requirements of ANSI/MSE 2000-2008 into their existing Operations Management System at the Waxahachie plant. The company plans to roll out the program to other facilities within the division and eventually throughout the company. Managers at the Waxahachie plant developed a list of energy efficiency opportunities to meet corporate goals of reducing energy use 25% over a 10-year period. The site participated in testing the compressed air and process heating system assessment standards, trained staff engineers in the process and confirmed the opportunities previously identified. The plant will kick off the M&V phase of the pilot project in fall 2009.
"Dow has a strong energy efficiency improvement program that is driven from the CEO down through each business and subsidiary. The program has been very effective at driving improvements as measured by Dow Sustainability commitments. The challenge has been to drive the program down to the individual operating units. We believe that full implementation of the energy management standard will enhance our results in this regard. The management standard dovetails into the existing corporate and business energy improvement program and fits comfortably with the existing management systems in the operating units. The result has been enhanced operating discipline for energy efficiency without creating a great deal of additional work."
Dave Hake, Site Integration Leader
Union Carbide Corporation: A subsidiary of Dow Chemical Company, the Union Carbide Texas City manufacturing operations consist of 10 production plants that produce approximately 2.5 billion pounds of alcohols, carboxylic acids, esters, aldehydes, vinyl acetate, and vinyl resins each year. Production of these chemicals demands approximately 7,250,000 MMBtu per year of steam, fuel, and electricity.
The company boasts a strong energy efficiency and management program, and actively participates in DOE's Save Energy Now initiative and the EPA ENERGY STAR for Industry program. Dow welcomed this pilot program opportunity as another vehicle by which to improve the energy efficiency of its operations. In testing the proposed steam system assessment standard, the company identified opportunities to recover heat from condensate and potentially purchase steam at a higher temperature, in addition to validating the current energy efficiency project list. In all, more than $6 million in energy cost-saving opportunities have been identified.
What Works?
As a result of this pilot project, six key activities have been identified that contribute to a timely, successful implementation of the Superior Energy Performance program:
- Leverage existing environmental or quality management systems and staff.
- Cross-train your energy and management system staff.
- Create cross-functional teams.
- Establish management commitment upfront and keep communicating to management on project status.
- Hold regular team meetings during the implementation phase.
- Take a structured look at data using statistical methods to realize immediate benefits.
In spite of several challenges during the pilot program—complexity of coordinating efforts between team members in different locations, time and resource constraints, unplanned weather events (Hurricane Ike), and the effects of the economic downturn on production, resources, and capital—the Texas pilot program is proving successful in helping to refine the program for manufacturers.
Next Steps
The Texas pilot project will continue through spring 2010 during which time the plants will continue to implement energy efficiency projects, put the management system in place, and participate in monitoring and verification of energy intensity progress. As a result of the pilot project, the initial Superior Energy Performance program criteria have been revised for greater flexibility and usability for all industry participants.
Learn more about Superior Energy Performance, and watch for updates on the Texas pilot plant project.
Compressed Air System Upgrade Increases Efficiency and Saves Energy at a Newspaper Plant
In August 2004, the San Jose Mercury News finished upgrading the compressed air system at its newspaper printing facility in San Jose, California. Before the upgrade, the compressed air system's performance had become erratic and energy costs were rising. To improve the system's efficiency and performance, the Mercury News commissioned a system-level evaluation of the compressed air system by Air Perfection, a U.S. Department of Energy (DOE) Allied Partner. The assessment, which included an AIRMaster+ analysis, was carried out by an Air Perfection employee who is a Qualified AIRMaster+ Specialist. The final report provided AIRMaster+ estimates of potential energy savings and a system-level strategy to improve the system. This project resulted in a system with better compressor control, a lower leak load, more stable pressure levels, and improved air treatment. These added up to better performance as well as energy savings.
Project Benefits
- Saves $96,000 annually
- Reduces annual energy consumption by 800,000 kilowatt-hours (kWh)
- Improves system performance
- Achieves a 16-month simple payback
San Jose Mercury News Building
Compressed air systems are found throughout industry, and can consume a significant portion of the electricity used by manufacturing plants. Using a system-level strategy to improve a compressed air system is the best way to enhance system performance, increase efficiency, and save energy.
The San Jose Mercury News, a Knight Ridder company, was founded in 1851. The newspaper maintains 13 bureau offices and has a daily circulation of 263,000 readers. Circulation extends from San Francisco to Monterey. The San Jose printing plant is a 410,000-square-foot building housing 1,500 employees.
The compressed air system at the San Jose facility includes six 100-horsepower rotary screw compressors. Because of fluctuating air demand patterns, the system's performance was erratic; all six compressors had to be operated at once to maintain consistent production levels. This operational pattern wasted energy and placed extra stress on end-use equipment. In the system-level review, the Qualified AIRMaster+ Specialist found that air demand patterns could be controlled by increasing the storage capacity, improving compressor controls, and installing a pressure/flow controller. In addition, he determined that air quality could be improved by adding mist-eliminator filters, and that the plant's compressed air load could be reduced by fixing leaks. Plant personnel found that implementing these measures improved the performance of the compressed air system considerably. In addition to having a more consistent air supply and more stable pressure levels, the plant now needs to operate fewer compressors to satisfy its air demand.
Project Results
The compressed air system project at the San Jose plant is yielding impressive energy savings, and there is less production waste. Measurements of the system's energy use since the project was completed indicate that annual energy savings of 800,000 kWh and energy cost savings of $96,000 can be expected. These savings are consistent with AIRMaster+ estimates. After the plant received a rebate from Pacific Gas & Electric, total project costs were $129,000. With total annual savings of $96,000, the project yields a simple payback of a little more than 16 months.
Lessons Learned
In many industrial plants that use compressed air, fluctuating system pressure is a frequent problem that is often misinterpreted as insufficient pressure. A common response is to bring additional compressors online to make up the perceived shortfall, which wastes energy. However, in most cases the pressure level can be stabilized without activating more compressors. By applying a system-level approach, industrial end-users can uncover the root cause of the pressure fluctuation and determine how to best stabilize system pressure. At the San Jose Mercury News plant, this approach uncovered several energy efficiency opportunities and led to the implementation of a project that optimized the system's efficiency and yielded significant energy savings. Furthermore, the plant was able to satisfy its production parameters while operating fewer compressors. This methodology, which relied on AIRMaster+, can be successfully applied in many types of industrial plants that use compressed air.
Project Partners
San Jose Mercury News
San Jose, CA
Air Perfection
Dixon, CA
Pacific Gas & Electric Co.
San Ramon, CA
Specialist Profile
Dan McCoin is the manager of field service technicians at Air Perfection and has 29 years of experience working with compressed air systems. As an AIRMaster+ Qualified Specialist, he has been involved in dozens of successful compressed air system optimization projects that have yielded substantial energy savings. Dan has been particularly active in using AIRMaster+ to validate energy savings for local utility company rebate programs.
Qualified Specialists
Qualified Specialists are industry professionals who identify cost-cutting and efficiency opportunities in industrial plants. Experienced professionals who complete a qualification training workshop and exam for specific DOE-developed software tools receive special designations, and they can use these tools to help plants reduce costs, decrease maintenance and downtime, and improve productivity. The training recognizes and enhances a professional's expertise in the use of DOE's AIRMaster+ software tool, Pumping System Assessment Tool, Process Heating Assessment and Survey Tool, and Steam System Tools.
Identifying Ways to Decrease Waste Provides Opportunities to Improve Resource Utilization, Conserve Energy, and Save Money
This study — which is the first phase of a long-term, two-phase project — estimated that implementing certain projects could reuse 155 million pounds per year of nonchlorinated waste by-products. The study also found that the energy savings potential could be 900,000 MMBtu per year. Dow is currently partnering with the U.S. Business Council for Sustainable Development to determine ways to implement the second phase of the project, which will involve identifying opportunities for synergy among various diverse companies and industries.
Benefits
- Identified potential annual cost savings of $15 million
- Found opportunities to reduce fuel use by 900,000 MMBtu per year
- Identified ways to decrease waste material production as much as 155 million pounds per year, turn the waste into useful products, and thus improve productivity, profitability, and community relations
- Found opportunities to reduce CO2 emissions by 108 million pounds per year
Six Gulf Coast Dow Chemical Company manufacturing facilities participated in a study that focused on finding ways to reuse nonchlorinated wastes. The objective was to identify opportunities for waste reuse and for achieving greater synergy within Dow by crossing the boundaries between businesses, sites, and plants.
The By-Product Synergy process developed by the U.S. Business Council for Sustainable Development provides manufacturing facilities with opportunities to reduce pollution and save energy and money by working with other plants, companies, and communities to reuse and recycle wastes. The process brings clusters of facilities together to create closed-loop systems in which one facility's wastes become another's useful raw materials. These synergies reduce waste and promote the efficient use of natural resources.
The U.S. Department of Energy's (DOE) Industrial Technologies Program (ITP) cosponsored the assessment. DOE promotes plant-wide energy-efficiency assessments that will lead to improvements in industrial energy efficiency, productivity, and global competitiveness, while reducing waste and environmental emissions. In this case, DOE contributed $100,000 of the total $205,000 assessment cost.
Plant Description
This project was a joint effort between Dow Chemical Company and the U.S. Business Council for Sustainable Development (US BCSD). Dow provides chemical, plastic, and agricultural products and services to a variety of consumer markets. The US BCSD is a nonprofit association of businesses whose purpose is to develop projects that demonstrate the business value of sustainable development. To do this, the US BCSD leverages industry resources with matching funds from government, foundations, and partner organizations.
Six major Dow manufacturing sites along the Gulf Coast participated in the study — four in Texas (Freeport, La Porte, Seadrift, and Texas City) and two in Louisiana (Plaquemine and St. Charles). Within the six sites, the study focused on 40 manufacturing plants representing various businesses that are supported by 14 business technology centers. The plants were identified as major generators of nonchlorinated waste; each plant produced more than 1 million pounds of waste per year. In this portion of the project, participants wanted to look for ways to reuse nonchlorinated wastes and to gain experience in using US BCSD's By-Product Synergy (BPS) process effectively. The objective was to identify opportunities for synergy within Dow and among the 40 plants by crossing business, site, and plant boundaries. This was the first phase of a long-term, two-phase project; the second phase will identify synergy opportunities among other companies and industries.
Assessment Approach
The underlying concept of BPS is that everything in the Earth's natural ecosystem is used by some member of it, so nothing is wasted. Therefore, the BPS philosophy is to enhance the emergence of a diversified industrial ecosystem that relies on cooperation among the actors involved. In other words, industrial plants use each other's waste material and energy as resources to minimize the amount of virgin material and energy they consume as well as the waste and emissions they produce.
BPS brings neighboring industrial companies and organizations together to exchange basic information about their processes in order to identify potential synergies. The synergies can result in added revenues, new business opportunities, cost savings, and environmental and regulatory benefits to the industrial group as well as to the group's geographic region. The BPS methodology involves establishing a forum where engineers and experts in various processes explore reuse opportunities, collect information, and facilitate interactions among individuals, business units, and companies to identify the possibilities for reusing by-products.
In this study, the BPS methodology was combined with Dow's Six Sigma approach to decision-making. Six Sigma is a method that is intended to virtually eliminate the defects in a process. Dow's approach employs a series of steps described as define, measure, analyze, improve, and control. Here, the process began with a definition of the project's team, objectives, and participants. This was followed by the measurement stage, in which each plant's inflows and outflows were catalogued. The inflows and outflows were then analyzed for synergies by an experienced project team and in facilitated working sessions with project participants. In this way, participants discovered and defined various potential improvements that could emerge through cross-business linkages. They created action plans for synergies judged to be commercially viable, and they organized strategies for addressing technical, regulatory, and other barriers. Ideas for improvements were captured in standardized business plans that could be used to communicate and control implementation.
Results and Projects Identified
Projects identified during the first phase of the survey were divided into six categories. This section describes the potential project categories and briefly discusses each one.
Recover Hydrocarbons and Spent Solvents
Several hydrocarbon and spent solvent streams were identified. Some are by-product compounds with chemical structures that are different from those of the desired intermediate products. The intermediate products are compounds that downstream customers could use in manufacturing other final products. Other by-products are waste solvents that have been used in manufacturing and are mixed with other compounds from the manufacturing process. Fifteen projects were identified in this category, and seven were recommended for implementation. The recommended projects cover seven types of hydrocarbon or solvent wastes that are mixtures of many compounds. An advanced separation technology could be used to extract a useful pure compound for use in other processes. Other applications might also be found that could make use of the particular physical or chemical characteristics of the by-product streams.
For example, if advanced separation technology could effectively separate ethyl acrylate and acrylic acid for reuse, incineration cost savings in combination with new revenue from recovered products could amount to as much as $3 million per year. However, capital and additional processing expenses would be needed. On the other hand, if new uses of the by-product as-is, or with little processing, could be identified, savings could also be close to $3 million per year. In that case, there would be little or no need for a major capital expense.
Reuse Sodium Hydroxide By-product
Several million pounds per year of low-concentration (1%-5%) sodium hydroxide (NaOH) solution are generated in the plants that were studied. Currently, much of this material is neutralized with acid and then discarded. In one proposed project, a team could assess the feasibility of increasing the concentration of the dilute waste NaOH to make it more usable. In another project, they could assess the possibility of converting the soluble NaOH in the dilute aqueous stream into more usable insoluble salts.
A successful project to convert a weak alkalinity by-product stream to magnesium hydroxide could yield estimated cost savings between $640,000 and $1.6 million. These savings would result from being able to reduce the use of hydrogen chloride to neutralize NaOH for disposal. Because of the high pH of the by-product stream, the material is classified as hazardous waste under the Resource Conservation and Recovery Act, and its pH must be reduced before disposal. The project could thus convert a hazardous waste into a useful product.
Reuse Sulfuric Acid Waste
Eight potential projects were identified, and three were recommended for implementation. Several different ideas were proposed that involve new on-site or external applications for medium-strength (~50%) sulfuric acid waste. Of the recommended projects, one involves assessing the potential use of sulfuric acid waste to control pH in the wastewater treatment unit, and another involves assessing the possibility of using the waste in another industry-for example, converting it to ammonium sulfate for use in manufacturing fertilizer.
Reuse Methocel Waste
Highly concentrated Methocel1 waste is currently incinerated. Synergy opportunities identified include (1) recovery of the crude cellulose ether and (2) making use of the physical and chemical properties that are attributes of the by-product to fulfill existing performance chemical needs and to create new applications.
Reuse Ortho-Toluenediamine (oTDA)
Ortho-toluenediamine (oTDA) is a relatively pure compound with no end-use customer. It is currently incinerated at a cost of hundreds of thousands of dollars per year. Synergy opportunities identified include (1) use the oTDA to manufacture polyols ; (2) sell it as raw material for use in manufacturing antioxidants, corrosion inhibitors, rubber chemicals, and dyes; and (3) make use of the physical and chemical properties that are attributes of the by-product to meet current performance chemical needs and to create new applications.
Reuse by-product hydrogen
The BPS project team discovered that some plants produce by-product hydrogen of various qualities, including "ultra-pure." They also discovered that other industrial plants buy pure hydrogen to use as a feedstock. The opportunity for synergy is to link plants that produce hydrogen as a by-product with those that can use it as feedstock.
Projected Savings
The total amount of nonchlorinated waste by-products that could be reused by implementing these projects was estimated by the study team to be 155 million pounds per year. The total energy savings potential of the recommended by-product conversions was estimated to be 900,000 MMBtu per year. The equivalent reduction in carbon dioxide (CO2) emissions would be 108 million pounds per year. The project team for the first phase of this work recommended focusing on synergy opportunities that do not require a significant capital investment. Potential annual cost savings were estimated to total $15 million.
Notes
1Methocel cellulose ethers are water-soluble methylcellulose and hydroxypropyl methylcellulose polymers that bind, retain water, thicken, form films, lubricate, and much more. They add unique physical properties and performance to many products, including building materials, food, personal care products, and pharmaceuticals. Methocel is a trademark of Dow Chemical Company.
2Polyols are alcohols having many hydroxyl radicals, and they include polyethers, glycols, polyesters, and castor oil. Polyol, also known as polyhydric alcohol, is used as a reactant.
Project Partners
Dow Chemical Company
Freeport, TX
U.S. Business Council for Sustainable Development
Austin, TX
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