ADVANCED POLLUTION PREVENTION

MEE 6201, Advanced Pollution Prevention 1

Course Learning Outcomes for Unit III Upon completion of this unit, students should be able to:

3. Explain pollution prevention audits.

Reading Assignment Chapter 7: Eco-audits and eco-audit tools Chapter 8: Case studies: eco-audits In order to access the resources below, you must first log into the myCSU Student Portal and access the Academic OneFile database within the CSU Online Library. Cheremisinoff, N. P. (2002). How to conduct a pollution prevention audit – Part 1: Do an audit in-house and

avoid surprises. Pollution Engineering, 34(3), 24-28. Cheremisinoff, N. P. (2002). Conduct a pollution prevention audit – Part 2: Do an audit in-house and avoid

surprises. Pollution Engineering, 34(4), 16-19.

Unit Lesson Nice job progressing through Units I and II. In Unit III, we'll study audits. Chapters 7 and 8 in the textbook discuss eco-audits. This lecture will teach pollution prevention audits. An eco-audit tends to focus on reducing energy use and reducing carbon dioxide (CO2) emissions. If non-fossil energy sources are used, then CO2 emissions are automatically eliminated, and the focus is on energy reduction to conserve resources. If fossil sources are used for energy, then the challenge, though somewhat the same, moves more toward CO2 reduction, which can occur from reducing energy consumption. While eco-audits focus on reducing energy consumption and reducing CO2 emissions, the P2 audit encompasses more than energy and has an ultimate goal of source reduction. Though the Pollution Prevention Act focuses on source reduction, over the years, businesses have broadened what they consider as pollution prevention (P2). According to Cheremisinoff (2002a):

P2 is any practice that:

 Reduces the amount of any hazardous substance, pollutant or contaminant reentering any waste stream or otherwise released into the environment prior to recycling, treatment and disposal.

 Reduces the hazards to public health and the environment associated with the release of such substances, pollutants or contaminants.

 Reduces or eliminates the creation of pollutants through increased efficiency in the use of raw materials or through protection of natural resources by conservation. (p. 24)

Cheremisinoff (2002b) includes the corporate bottom line, "A P2 investment must be able to stand up to every other funding request and effectively compete for money on its own merits" (p. 16). Thus, though companies must comply with the laws listed in the Unit I lecture (often seen as costs rather than benefits to management) as they conduct their business, it behooves companies to look at P2. Not only is P2 helpful to the environment, good P2 programs benefit a company's finances. In Unit II, you were introduced to life cycle analysis (LCA). Understanding the life cycle of a product enables the P2 manager to locate P2 possibilities, such as fixing leaky pipes or using more efficient fuel sources. The

UNIT III STUDY GUIDE

Pollution Prevention Audits

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textbook reading for Unit III covers eco-audits, while the supplemental readings cover P2 audits. What is the difference? An eco-audit focuses on energy use and carbon dioxide (CO2) emissions with the goal being to reduce those two quantities. While a P2 audit will locate production areas where energy usage can be reduced, it doesn't have the same focus on reducing CO2 emissions as in an eco-audit. A P2 audit looks at all types of pollution produced, excess energy used, and protection of resources. Thus, it is broader than an eco-audit. The LCA and P2 audit tend to overlap in coverage but differ in when they are conducted. An LCA is often conducted before a process is built, while a P2 audit is conducted during operation. Cheremisinoff (2002b) outlines the elements of a P2 audit. The primary phases are:

1. Phase I: Pre-assessment for audit preparation. 2. Phase II: The in-plant assessment. 3. Phase III: Synthesis, benchmarking, and corrective actions. (p. 17)

Table 1 shows the steps within each phase of a P2 audit.

Phase I: The Pre-assessment (quoted from Cheremisinoff, 2002b)

Step 1 Audit Focus and Preparation

Step 1.1 Get Ready

Step 1.2 Assemble the Audit Team

Step 1.3 Identify and Allocate Additional Resources

Step 1.4 Select the Subject Facility

Step 1.5 Define the Audit Objectives

Step 1.6 Review Documentation

Step 1.7 Gain Employee Buy-in and Participation

Step 2 List the Unit Operations

Step 2.1 Refine Our Initial Checklist

Step 2.2 Conduct an Initial Walk-through

Step 3 Constructing Process Flow Sheets

Step4 Preliminary Assessment and Next Steps

Phase II: The In-plant Assessment

Step 5 Determining the Inputs

Step 5.1 Determine the Total Inputs

Step 5.2 Determine the Inputs to Unit Operations

Step 5.3 Consider the Energy Inputs

Step 5.4 Record Information on Process Flow Sheets

Step 6 Accounting for Water Usage

Step 7 Measuring Current Levels of Water Use and Recycling

Step 8 Quantifying Process Outputs

Step 9 Accounting for Wastewater Flows

Step 9.1 Identify the Effluent Discharge Points

Step 9.2 Plan and Implement a Monitoring Program

Step 9.3 Reconciling Wastewater Flows

Step 9.4 Determine the Concentrations of Contaminants

Step 9.5 Tabulate Flows and Concentrations

Step 10 Accounting for Gaseous Emissions

Step 10.1 Quantify the Gaseous Emissions

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Step 10.2 Tabulate Flows and Concentrations

Step 11 Accounting for Off-Site Wastes

Step 12 Final Preparation for the Material-Balance System

Step 13 Construct a Material Balance Information Sheet

Step 14 Evaluating Material Balances

Step 14.1 Classify the Material Balances

Step 14.2 Determine the Gaps and Inaccuracies

Step 15 Refine the Material Balances

Phase III: Synthesis, Benchmarking, and Corrective Actions

Step 16 Low-cost/No-cost Recommendations

Step 17 Targeting and Characterizing Problem Wastes

Step 18 Segregation

Step 19 Developing Long-Term Waste-reduction Options

Step 20 Environmental and Economic Evaluation of P2 Options

Step 21 Developing and Implementing the Action Plan (p. 17)

Table 1 is a good outline of a P2 audit. Specific industries or processes may have other steps, however. Several sections of the audit will be presented as examples. As an example, consider a fictitious company called ALref that refines aluminum. Recall from Unit II that a refinery separates aluminum oxide from bauxite rock and creates alumina. Alumina chemically is Al2O3 and looks like white powder. Example of Step 1.1 Step 1.1 Get Ready: April 11, 2016: Have staff in place for audit. Begin Phase I. May 6, 2016: Have Phase I completed. May 9-20, 2016: Discuss Phase I. Modify Phase II and III as needed. May 23, 2016: Begin Phase II. July 22, 2016: Have Phase II completed. July 25 - Aug 5, 2016: Discuss Phase II. Modify Phase III as needed. Aug. 8, 2016: Begin Phase III. Nov. 18, 2016: Complete Phase III. Nov. 21 - Dec. 9, 2016: Discuss Phase III. Example of Step 1.7 Step 1.7 Gain Employee Buy-in and Participation: Set up incentive program for employees to report leaks, suggest where there are inefficiencies, suggest alternative energy sources, and suggest P2 opportunities that they spot. Do not chastise employees for trying to change anything. Encourage them to find and discuss possibilities for improvement. Provide $20 gift cards to lower-level staff who propose ideas that get implemented. Example of Step 2 (unit operations from Advameg, 2015) Step 2. Listing the Unit Operations:

 Crusher: Crushes the bauxite rock.

 Grinder: Adds caustic soda (sodium hydroxide NaOH) and water to the crushed rock to dissolve it and create liquid slurry containing small-sized ore particles.

 Digestion: Adds additional heat and pressure to the slurry, lets it digest for an hour or so, then depressurize and reduce the temperature. Result is a mixture of suspended solids.

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 Clarification: Settles out the heavier materials which are waste products called "red mud" (sand, iron oxides and trace elements from the bauxite). The liquid in the tanks has a consistency of coffee and is filtered. Material on the filters is aluminum oxide but is not yet the finished product.

 Precipitation: The wet aluminum oxide is put in a precipitation tank where aluminum oxide crystals are added as a seed to the wet aluminum oxide. The wet aluminum oxide gathers on the seed making bigger crystals. The crystals settle out.

 Calcination: The settled out crystals from the precipitation process are heated to dry them. The result is the final alumina product.

The unit operations are the key to a P2 audit since they will lead to P2 opportunities that can be listed in Phase III. As a student preparing a P2 audit for our course, you will likely have references (such as the ones listed in this lecture) due to unfamiliarity with the processes. However, as a real employee of a company preparing a P2 audit, you will be familiar with the unit operations and thus would not have references. As you move into Phase II of the P2 audit, useful information for Steps 5 ("Determining the Inputs") and 6 ("Accounting for Water Usage") can be found in Chapter 15 of our textbook. The chapter has over 100 pages of energy and water requirements to produce various products. Example of Phase II's Step 13 Material Balance Using flow meters, measure flow rate Q1 (gpm, i.e. gallons per minute) of water into the grinding process. From stoichiometry and heat balances, determine how much water is used in the process (Q2). Measure Q3, which is the flow of water (gpm) out of the process. Ideally, Q3=Q1+Q2. If the computed Q3 and measured Q3 are different by over 10%, then look for leaks in the system. List material balances for all processes. This lecture presents a P2 audit outline with examples of some of the sections as well. Please refer to Chapter 8 of our textbook, "Case studies: eco-audits," for examples of eco- audits. Some of the information from an eco-audit (e.g. energy usage, materials used, and water consumption) can be used in a P2 audit. The recommendations in Phase III of the P2 audit should be very specific. As an ALref P2 manager, you will have walked around the alumina refinery numerous times, becoming very familiar with the workers and processes. That familiarity, along with math computations of material and energy balances, will provide you with knowledge of where source reduction and other P2 options can be implemented. Chapter 8 of our textbook gives very specific numbers for energy use, material quantities, water consumption, and other items. That type of detail should be in a P2 audit. Cheremisinoff (2002a) provides additional examples of P2 audits. This lecture has contained a lot of information. You now have an idea of the aspects of a P2 audit. Now, it's time to go to work and prepare an audit!

References Advameg, Inc. (2015). How products are made: Volume 5 – aluminum. Retrieved from

http://www.madehow.com/Volume-5/Aluminum.html Ashby, M. F. (2013). Materials and the environment: Eco-informed material choice (2nd ed.). Waltham, MA:

Butterworth-Heinemann. Cheremisinoff, N. P. (2002a). How to conduct a pollution prevention audit – Part 1: Do an audit in-house and

avoid surprises. Pollution Engineering, 34(3), 24-28. Cheremisinoff, N. P. (2002b). Conduct a pollution prevention audit – Part 2: Do an audit in-house and avoid

surprises. Pollution Engineering, 34(4), 16-19.

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Suggested Reading The following reading addresses eco-data. Chapter 6: Eco-data: values, sources, precision The chapter includes detailed costs, mechanical, thermal, electrical, and eco properties of many materials, which are useful to a P2 analysis and/or audit. Chapter 15: Material profiles