Lean Manufacturing and Environment
The Lean and Chemicals Toolkit
Chapter 3: Driving Out Chemical Waste with Lean Events
On This Page
- Value Stream Mapping Events
- Kaizen Events
Lean events are critical for identifying wastes in a value stream and implementing process improvements to eliminate those wastes. This chapter describes strategies for reducing chemical wastes in the following two types of Lean events:
- Value Stream Mapping Events
- Kaizen Events
Value stream mapping is a Lean method for creating a visual representation of the flows of information and materials (work in process) between all the activities involved in producing a product for a customer. (1) The power of value stream mapping lies in walking the plant floor, talking to workers, and closely observing how a product is actually made. Lean practitioners use value stream mapping to:
- Identify major sources of non-value added time in a value stream (depicted on a “current state” map);
- Envision a less wasteful future state (often shown on a “future state” map and/or an “ideal state” map); and
- Develop an implementation plan for future Lean activities, including kaizen events to improve specific processes in the value stream.
Involving people (internal staff or external experts) with environmental health and safety (EHS) expertise in value stream mapping is one of the most effective ways to enhance your facility’s Lean and environmental performance. Consider inviting EHS staff at your facility to value stream mapping events to identify additional sources of waste in the value stream, quantify environmental wastes and costs associated with processes, and offer outside perspectives on potential process improvement opportunities.
With some minor additions, value stream maps can become powerful tools for learning to see chemical wastes—how chemicals can affect time, quality, and cost. Two strategies for incorporating chemicals into value stream mapping are described below:
- Adding chemical metrics to value stream maps
- Examining key environmental inputs and outputs in value stream maps
See Chapter 3 of EPA’s Lean and Environment Toolkit (http://www.epa.gov/lean/toolkit/ch3.htm) for additional strategies for reducing environmental wastes using value stream mapping.
Although the most common metrics on value stream maps relate to time (e.g., cycle time, changeover time, value added time, and non-value added time), the data boxes in value stream maps can also record other key data for each process, such as environmental wastes and costs.
Add chemical waste information to process data boxes on the current state value stream map to analyze and record how much waste is generated at each process. For example, you could record the amount of hazardous waste generated by a process over a certain time period (e.g., per shift), or you could quantify the costs associated with those wastes. Be sure to include the cost of purchasing the raw materials, time spent managing the wastes, and disposal costs. Figure 4 shows process data boxes with environmental waste included (labeled “FO” for “fallout” wastes in this example). Figure 5 shows an example of a current state value stream map with chemical metrics included.
Process Boxes Showing Environmental Wastes (Figure 4)
Current State Map with Chemical Metrics (Figure 5)
When chemical metrics are integrated into the current state map along with other Lean metrics, the team conducting the value stream mapping event can use those data to see a more complete picture of the wastes in the value stream and the potential for improvement opportunities. That is, the chemical data can inform the development of a future state map for the value stream and an implementation plan to achieve that future state. Consider identifying at least one kaizen event that targets a large source of chemical waste.
Chemical wastes can occur in many parts of the value stream. Too much chemical inventory could lead to expired or off-spec chemicals that require disposal. Excess use of chemicals beyond what adds value from the customer’s perspective and improper use of chemicals (e.g., incorrect mixing) in processes also result in waste. In the chemical manufacturing industry, key sources of waste include chemical reactors, separations, and other process equipment. For example, many chemical reactors require a lot of reactant feed and/or reaction conditions that are crucial to producing the product. Chemical reactors often require precise control of many inputs. If reactant feeds or operating conditions deviate from target values, the process yield may suffer or “off-spec” products may be produced, both of which will likely lead to increased waste.
Another way to examine environmental wastes in value stream mapping events is to record the key resource “inputs” to each process (e.g., raw materials, energy, and water use) and the key non-product “outputs” that result from each process (e.g., scrap, air emissions, hazardous waste, etc.) directly onto value stream maps. Use different colored lines to show resource flows and waste flows out of each process data box on the value stream map. In the chemical context, inputs would include chemicals used in the process and non-product outputs would include any hazardous wastes generated (e.g., hazardous chemicals mixed with other materials). Figure 6 provides a conceptual outline of how to add resource input and waste output lines to process maps, while Figures 7 and 8 depict full value stream maps incorporating the input and output lines.
Conceptual Outline of Adding Environmental Inputs and Outputs
on Value Stream Maps (Figure 6)
Photo of Modified Value Stream Map (Figure 7)
Value Stream Map Incorporating Environmental Inputs and Outputs (Figure 8)
Source: This figure is based on a Lean and environment value stream map developed by the Oregon Manufacturing Extension Partnership, http://www.omep.org.
This method combines concepts of traditional Lean value stream mapping with the materials flow process mapping used by pollution prevention (P2) experts. Although the resulting value stream map could look complicated, it can be very powerful to see the Lean and environmental wastes together on a single map. Detailed hierarchical process mapping of environmental inputs and outputs can also supplement value stream maps and/or be developed and used in kaizen events to improve specific processes. See Chapter 4 (Kaizen Events) of EPA’s Lean and Environment Toolkit for more information about hierarchical process mapping.
Value Stream Mapping at Woodfold Manufacturing, Inc. (Box 6)
- In 2007, Woodfold Manufacturing, Inc., a manufacturer of custom wood products located in Forest Grove, OR, participated in a Lean and environment project with Oregon Manufacturing Extension Partnership (OMEP) and the Pollution Prevention Resource Center (PPRC).
- OMEP facilitated a value stream mapping event that targeted a shutter painting line, while PPRC and Woodfold staff provided environmental expertise. The event addressed chemical use and hazardous wastes associated with painting, along with other environmental impacts.
- The project team closely scrutinized the process, noted environmental inputs and outputs on the process boxes on the value stream map, and identified potential future Lean and environmental improvements.
- Woodfold implemented many of the improvement opportunities identified in the event, and achieved the following results:
- Saved about $44,800 per year, including $34,700 per year from improvements to paint spray transfer efficiency.
- Found a local recycler for PVC scrap, diverting 6 tons per year of solid PVC waste from the landfill.
- Reduced volatile organic compound (VOC) emissions by nearly 1,000 lbs per year.
Source: Correspondence with Kevin Emerick, EHS Manager at Woodfold Mfg., and PPRC, “Lean Green Manufacturing Case Study: Woodfold Mfg., Inc.,” 2007, www.pprc.org/solutions/woodfoldcasestudy_12_07.pdf.
Kaizen is a combination of two Japanese words meaning “take apart” and “make good;” kaizen refers to the philosophy of continual improvement. Kaizen events—also known as rapid process improvement events—are a team activity designed to eliminate waste and make rapid changes in the workplace in a 2–5 day period. (2) They are a primary means of implementing other Lean methods, such as standard work, 5S (or 6S), one-piece flow, and customer-driven “pull” production.
One of the most important ways to reduce chemical wastes and avoid potential regulatory issues is to involve staff with EHS expertise in planning for and conducting kaizen events on environmentally sensitive processes. In particular, if there’s someone at your organization who specializes in chemicals and hazardous waste management, consider inviting that person to participate in value stream mapping events or kaizen events targeting processes that deal with chemicals. Box 7 lists several processes with the potential for significant chemical wastes.
Processes with Chemical Wastes (Box 7)
- Bonding and sealing
- Chemical and hazardous materials management
- Chemical manufacturing
- Cleaning and surface preparation
- Metal fabrication and machining
- Metal finishing and plating
- Painting and coating
- Waste management
Many types of Lean events would benefit from EHS staff involvement, especially during the planning phase, to avoid potential regulatory compliance issues and identify additional waste-reduction opportunities. Use the list of Common Operational Changes That Trigger EHS Involvement below as a guide for when to seek additional EHS expertise for Lean events. If EHS staff participated in the value stream mapping event to select Lean implementation priorities, your team should have a good idea of which events would benefit from EHS expertise.
Common Operational Changes That Trigger EHS Involvement (Box 8)
- Changes to the type, volume, or introduction/issuance procedure for chemicals/materials used by employees. Affects chemical exposure, regulatory compliance, and reporting needs.
- Changes to the nature, concentration, or volume of waste generated by a process, including all media such as air emissions, water discharges, and liquid and solid waste. Affects compliance with regulatory and permitted limits, as well as pollution control and management capacity.
- Changes to the physical layout of the processes (e.g., moving work or storage areas), to equipment and technologies used, or to the facility (e.g., moving, replacing, or installing vent hoods, stacks, floor drains or process tanks). Affects compliance with regulations and permits, as well as work practice requirements.
If not properly conducted, these types of operational changes could harm the health and safety of workers, or cause violations of EHS regulations. For example, moving hazardous waste collection areas from central locations to work cells could affect compliance with waste management regulations (e.g., Resource Conservation and Recovery Act regulations). (3) Similarly, replacing existing air pollution control equipment with new right-sized equipment would require permit modifications under the Clean Air Act.
For a more formal system for identifying when to involve EHS experts in Lean events, use the Lean Event EHS Checklist included in EPA’s Lean and Environment Toolkit (the checklist is available at http://www.epa.gov/lean/environment/environmenttoolkit/app-c.htm). Requiring team leaders to complete this form helps ensure that Lean teams involve EHS staff in Lean events when appropriate.
All kaizen event participants can help to identify chemical wastes in processes. Use the Key Questions for Identifying Chemical and Hazardous Waste Reduction Opportunities below as a guide.
Key Questions for Identifying Chemical and Hazardous Waste Reduction Opportunities (Box 9)
- What types and in what quantities are chemicals used in the process?
- How can you reduce the overall amount of chemicals used? Can you switch to less harmful chemicals?
- How can you reduce the number of chemicals used?
- Can you eliminate any non-value added use of chemicals from the product or process (unneeded painting, etc.)?
- Is there an effective way to meet customer needs without chemicals? For example, can metal fasteners be used instead of chemical adhesives?
- What types and quantities of hazardous waste are generated by the process?
- How can you reduce the amount of hazardous waste generated?
- Can you better isolate and separate hazardous wastes from other wastes?
- Can you find opportunities to reuse or recycle any chemicals or hazardous wastes?
Environmental health and safety professionals and technical assistance providers can support kaizen event teams by researching chemicals used in the process, identifying less hazardous chemicals that could be used as alternatives, and finding sector-specific resources and tools for reducing chemical wastes. Appendix A describes several resources that can help reduce chemical wastes and identify safer alternatives to hazardous chemicals; the Appendix also lists non-profit technical assistance providers, as well as general resources about chemicals.
Asking “why” five times is a useful strategy for identifying the root causes of wastes. This approach often reveals simple solutions to eliminate wastes that save time, cut costs, and improve the quality of the process. Box 10 describes an example of how the five whys technique can identify causes of chemical wastes.
Asking Why Five Times (Box 10)
Asking “why” five times is a simple way to identify the root cause of a waste, and that makes it easier to identify ways to reduce or eliminate the waste. Here is an example:
- Why is the solvent a waste? Because the solvent is contaminated with oil.
- Why is it contaminated with oil? Because the solvent was used to clean oil off the parts.
- Why are the parts oily? Because the manufacturer puts a coating of oil on them before shipping them to this facility.
- Why does the manufacturer put a coating on them? To prevent the parts from corroding after manufacture.
- Why is this type of corrosion protection absolutely necessary? We don’t know any other ways to protect the parts from corrosion. Let’s form a team to identify and test some alternatives.
In this example, the root cause of solvent waste is corrosion protection. There may be other ways to achieve that objective without using oil.
Source: Arizona Department of Environmental Quality, Pollution Prevention Analysis and Plan Guidance Manual, March 2006, www.azdeq.gov/environ/waste/p2/download/first.pdf.
Canyon Creek Cabinet Company “Toxics Team” (Box 11)
- Canyon Creek Cabinet Company—a large manufacturer of custom frameless and framed cabinetry based in Monroe, WA—worked with the Washington State Department of Ecology and Washington Manufacturing Services in a Lean and Environment Pilot Project to evaluate the benefits of integrating environmental tools into Lean.
- A cross-functional project team called the “Toxics Team” conducted a value stream mapping workshop and three kaizen events on the finishing department, where products are stained and coated.
Stain Booth, Before the Project
Stain Booth, After the Project
- The Team analyzed environmental wastes alongside other production wastes, and implemented process changes that improved process efficiency, cut costs, and reduced wastes.
- The company is saving $1 million per year from the project. The chemical-related results were impressive:
- Reduced hazardous substances used by 68,700 lbs per year by installing dedicated pumps for each solvent-based stain color.
- Decreased hazardous wastes by 84,400 lbs per year by reducing wastes from changeover of aqueous and solvent-based stains.
- Cut volatile organic compound (VOC) emissions by 55,100 lbs per year, primarily by employing a new unicoat product to replace the existing sealant and topcoat. These changes allowed the facility to increase production capacity up to 70 percent before reaching the Clean Air Act Title V threshold for VOCs.
For more information about the project, see the Washington State Department of Ecology’s Lean and Environment website, http://www.ecy.wa.gov/programs/hwtr/lean.
To really drive out chemical wastes at your facility, conduct kaizen events that focus specifically on eliminating chemical wastes. As a starting place, use value stream maps and/or other information to identify processes that generate large quantities of hazardous wastes. Then harness the power of a cross-functional team of employees in a kaizen event to identify and implement process changes to reduce those wastes. In the longer term, consider redesigning processes so that they do not require hazardous chemicals as inputs. Box 11 above describes an example of a Lean and environment project that focused on reducing chemical wastes, along with other Lean wastes.
- What processes use the most chemicals, or the most toxic chemicals at your facility? What steps would you take to find out?
- Do you know which processes generate the most hazardous waste at your facility? What steps would you take to find out?
- What ideas do you have for reducing chemical wastes?
- Have you invited Environmental Health and Safety personnel to participate in Lean events?
- Is there a specific process at your facility that uses large amounts of chemicals that you could target in a chemical-focused kaizen event?
- Is there a process at your facility that uses a particularly toxic chemical that you could target in a chemical-focused kaizen event?