Process Engineering for Pollution Control and Waste Minimization_1 pdf

dis-ISO 14000 International Standardization of Environmental Management System Standard which is “that part of the overall management systemwhich includes organizational structure, plann

1 Chemical and Engineering News, vol 77, no 17, p 10, April 26, 1999.

2 Independent Technical Review of Three Waste Minimization and Management Programs, p 3-2 Albuquerque, NM: U.S Department of Energy, Albuquerque and Oakland Office, August 1995.

3 EPA Pollution Prevention Policy Statement: New Directions for Environmental Protection, June 15, 1993.

4 EPA Pollution Prevention Solutions During Permitting, Inspections and Enforcement EPA/745-F-99-001, p 29, June 1999.

5 Characterization of Municipal Solid Waste in the United States: 1996 Update, U.S EPA, Office of Solid Waste, EPA530-R-97-015, p 10 Prepared by Franklin Associ- ates, Prarie Village, KS, June 1997.

6 EPA Federal Facility Pollution Prevention: Tools for Compliance, EPA/600/R-94/154,

9 EPA Environmental Management Systems Bulletin 1, EPA 744-F-98-004, July 1998.

10 U.S EPA Waste Minimization EPA Assessment Manual, PEA/625/7-88/003, pp 6–

10 Cincinnati, OH: Hazardous Waste Engineering Research Lab, July 1988.

11 U.S EPA Facility Pollution Prevention Guide, EPA/600/R-92/088, Washington, DC, May 1992.

12 Characterization of Municipal Solid Waste in the United States: 1996 Update, U.S EPA, Office of Solid Waste, EPA530-R-97-015, p 89 Prepared by Franklin Associ- ates, Prarie Village, KS, June 1997.

13 Guidance for ROI Submissions Albuquerque, NM: U.S Department of Energy, 1996.

14 Environmental Protection Agency, U.S Office of Research and Development, ance for the Data Quality Objectives Process, EPA/600/R-96/055, Washington, DC, September 1994.

Guid-15 U.S EPA Facility Pollution Prevention Guide, EPA/600/R-92/088, Washington, DC, May 1992.

ABBREVIATIONS

A annual costs after implementation of P2 project

B annual costs before implementation of P2 project

C capital investment for the P2 project

CERCLA Comprehensive Environmental Response, Compensation, and

Liability ActC&D construction and demolition debris

D estimated project termination/disassembly cost

D&D decontamination and decommissioning

EPCRA Emergency Planning and Community Right-to-Know Act

ISO 14000 International Organization for Standardization 14000

NPL National Priorities List

PPOA Pollution Prevention Opportunity Assessment

RCRA Resource Conservation and Recovery Act

RI/FS remedial investigation/feasibility study

WMin/P2 waste minimization/pollution prevention

GLOSSARY

Construction and demolition debris (C&D) The waste building

materi-als, packaging, and rubble resulting from construction, remodeling,repair, and demolition operations on pavement, houses, commercialbuildings, plants, and other structures

Data quality objective (DQO) Qualitative and quantitative statements

derived from the DQO process that clarify study objectives, define theappropriate type of data, and specify the tolerable levels of potentialdecision errors that will be used as the basis for establishing the qualityand quantity of data needed to support decisions It provides a systematicprocedure for defining the criteria that a data collection design shouldsatisfy, including when to collect samples, where to collect samples, thetolerable level of decision errors for the study, and how many samples tocollect

Decontamination and decommissioning (D&D) The process of

reduc-ing or eliminatreduc-ing and removreduc-ing from operation of the process harmfulsubstances, such as infectious agents, so as to reduce the likelihood of

disease transmission from those substances After the D&D operation,the process is no longer usable.

Demolition The wrecking or taking out of any load supporting structural

member and any related razing, removing, or stripping of a structure

Also called deconstruction.

Design for environment (DfE) The systematic consideration of pollution

prevention/waste minimization options during the design consideration

of any process associated with environmental safety and health over theproduct life cycle

Environmental assessment (EA) A document that briefly provides

suf-ficient evidence and analysis for determining whether to prepare anenvironmental impact statement or a finding of no significant impact.This document will include a brief discussion of the need for theproposal, of alternatives as required by EPA regulations, of the environ-mental impacts of the proposed action and alternatives, and a listing ofagencies and persons consulted

Environmental management system (EMS) A systematic approach to

ensuring that environmental activities are well managed in any tion It is very similar to ISO 14000

organiza-Environmental restoration (ER) Cleaning up and restoration of sites

contaminated with hazardous substances during past production or posal activities

dis-ISO 14000 International Standardization of Environmental Management

System Standard which is “that part of the overall management systemwhich includes organizational structure, planning activities, responsibil-ities, practices, procedures, processes and resources for developing,implementing, achieving, reviewing and maintaining the environmentalpolicy.”

Municipal solid waste (MSW) Residential and commercial solid wastes

generated within a community

Pollution prevention opportunity assessment (PPOA) A tool for a

company to identify the nature and amount of wastes and energy usage,stimulate the generation of pollution prevention and energy conservationopportunities, and evaluate those opportunities for implementation

Recycling of materials The use or reuse of a waste as an effective

substitute for a commercial product, as an ingredient, or as feedstock in

an industrial or energy-producing process; the reclamation of usefulconstituent fractions in a waste material; or removal of contaminantsfrom a waste to allow it to be reused This includes recovery forrecycling, including composting

Return on investment (ROI) The calculation of time within which the

process would save the initial investment amount if the suggested

changes were incorporated into it In this calculation, depreciation,project cost, as well as useful life are taken into account.

Source reduction Any practice which: (a) reduces the amount of any

hazardous substance, pollutant, or contaminant entering any wastestream or otherwise released into the environment prior to recycling,treatment, or disposal; and (b) reduces the hazards to public health andthe environment associated with the release of such substances, pollu-tants, or contaminants

Thermal destruction Destroying of waste (generally hazardous) in a

device which uses elevated temperatures as the primary means to changethe chemical, physical, or biological character or composition of thewaste Examples include incineration, calcination, oxidation, and micro-wave discharge Commonly used for medical waste

Toxic release inventory (TRI) Required by the EPCRA, a TRI contains

information on approximately 600 listed toxic chemicals that the ties release directly to air, water, or land or transportation of wasteoff-site

facili-Vitrification A process of immobilizing waste that produces a glasslike

solid that permanently captures radioactive materials

Waste combustion Combustion of waste through elevated temperature

and disposal of the residue so generated in the process It also mayinclude recovery of heat for use

Waste management (WM) Activities associated with the disposition of

waste products after they have been generated, as well as actions tominimize the production of wastes This may include storage, treatment,and disposal

of today is also discussed The objective is to raise awareness of both thecapabilities and limitations that are placed on society in the management of waste.

2 HISTORICAL PERSPECTIVE

While we have recently increased our awareness of environmental problems andwaste management, these issues have been in effect to some degree since societybegan to reach beyond simple existence Humankind for centuries has developedand exploited available resources in useful and necessary ways, along withwasteful approaches However, significant problems arose once communities,towns and cities developed into urban centers wherein contamination of water

supplies from waste and animals caused significant deaths to occur Furtherindustrialization and heavy dependence on fossil fuels has in the past centurygreatly increased pressure on the environment to cope with the anthropogenicmaterials and methods of humankind’s development The development of regu-lations in the United States, described below, best illustrates the interactions forsuch a heavily industrialized nation.

In earlier history the best examples of industrial pollution are found inEngland (2), where factories contaminated nearby rivers and raised awarenessabout the limitations of drinking water sources Air pollution resulted from use ofcoal for fuel, but it was only after many years, in the mid-1800s and later in the1900s, that regulations and cause-and-effect mechanisms led to control of pollu-tant levels Most unfortunate was the episode occurring in London duringDecember 1952 due to stagnant conditions over the city, wherein pollutantconcentrations resulted in death of about 4000 people from particulates and SO2

buildup This event was followed by the passage of the Clean Air Act by thegovernment of England, which laid the basis for pollution control in that country

In the United States, the historical perspective can be best representedthrough actions and activities in the United States and resulting regulations, to tietwo perspectives together Initial efforts were focused on water pollution by theRiver and Harbor Act of 1899, the Public Health Service Act of 1912, and the OilPollution Act of 1924, all being fairly localized in action Only after World War

II did the U.S government take significant action to control pollution problemswith the Water Pollution Control Act of 1948 and the following Federal WaterPollution Control Act (FWPCA) of 1956, which set funds for research andassisted in state pollution control with construction of wastewater treatmentfacilities In 1965, the Water Quality Act provided national policy for control ofwater pollution Focusing on drinking water, the Safe Drinking Water Act(SDWA) of 1974 directed the U.S Environmental Protection Agency (EPA) toestablish drinking water standards, which occurred in 1975 In 1980, Congressplaced controls on underground injection of waste, requiring permits for themethod Finally, the SDWA amendments of 1986 led to interim and permanentdrinking water standards

It was not until the 1972 amendments were made to the FWPCA that thenation implemented major restrictions on effluents to restore and maintain waterbodies in the United States The Clean Water Act of 1977 added to this focus withconsideration of toxins being 65 substances or classes as a basis to reduce andcontrol water pollution This action led to the initial priority pollutants list, whichincluded benzene, chlorinated compounds, pesticides, metals, etc In combina-tion, then, the FWPCA and CWA provided the National Pollution DischargeElimination System (NPDES) permit system in place today

These regulatory activities, while focused on water media and abatement

of problems in rivers and other water bodies, did not directly address the other

media in our ecosystem—soil (land) and air As industry responded to the waterregulations, unengineered disposal of waste on land (unengineered pits) became

an acceptable and legal method for waste management in many industrial streams,including petroleum wastes, petrochemical wastes and off-spec products, andsolid waste disposal (old garbage dumps) These activities led to numerous acts

to control and mitigate pollution from dumping, etc Initial efforts involvedcontrol of the transportation of solid food wastes for swine, for control oftrichinosis Modern regulations began with the Solid Waste Disposal Act (SWDA)

of 1965 and the National Environmental Policy Act of 1969, which requiredenvironmental impact statements The Resource Recovery Act of 1970 amendedthe SWDA about the time that the Environmental Protection Agency was formed.True regulation for solid waste management did not come into effect until theResource Conservation and Recovery Act (RCRA) of 1976, with guidelines forsolid waste management and a legal basis for implementation of treatment,storage, and disposal regulations Also, hazardous wastes and solid wastes weredefined by the RCRA With numerous amendments, the RCRA was followed bythe Comprehensive Environmental Response, Compensation and Liability Act(CERCLA) in 1980 to deal with abandoned sites and provide the funds andregulations to perform cleanups CERCLA, or Superfund, has been throughnumerous revisions, and its effectiveness has come under question due to the greatdeal of litigation involving cleanup of old sites

Air quality needs became apparent in the 1950s due to the Donora,Pennsylvania, accident, and the linkage shown between automobile emissions andphotochemical smog, but it was not until the Clean Air Act of 1963, andamendments in the 1960s, 1970s, and 1990s that true national programs wereestablished for pollution control in the air medium These regulations werefocused on motor vehicle emissions, and on emissions from industrial sources.Thus, the United States has “chased” waste management and pollution in allmedia, and while regulations are now complex, they do provide for control,management, and abatement of pollution from recognized sources to water, landand air

Two points develop from this brief historical–regulatory review First,waste is tied directly to population, and population is growing at a rapid rate, sothese growth centers must manage and direct waste properly to avoid release andcontamination problems Second, while many countries have significant controls

in place as in the United States, many Third World countries and underdevelopedregions are “behind the curve” in regulatory and technical development tomanage waste Many are still dealing with “end-of-pipe” technologies while theUnited States and others are dealing with remediation, mitigation, and pollutionprevention Still others lack the fundamentals of basic treatment technologies andhave significant population growth Thus our history, in the United States andEngland, has the potential to continue to repeat itself, unless proper technology

is brought to these developing population areas While the United States andEngland had time to deal with waste issues, our continued use and development

of agricultural land has diminished our resources, and places high stress on thoseagricultural lands to provide food for the expanding of society Hopefully, balancewill be achieved on a global scale in time to meet the population demandwith managed resources and sufficient waste management to protect all mediaand humankind

3 TECHNICAL APPROACH

In order to manage waste properly, we must explore the geography of a process

so that appropriate engineering (and the constraints of different areas of phy) can be applied to solve a waste management issue or problem Let us focusnow on a chemical manufacturing process, wherein raw materials are taken tomanufacture products, such as petroleum to petrochemicals for containers Thereare three distinct areas—the process itself, the facility boundary (fence line), and

geogra-“nature” outside the fence line Historical sites such as those covered in fund regulations also include a boundary and “nature.” Nature is defined here aseverything except humankind or society In order to properly apply a soundtechnical approach to the waste management of such a manufacturing facility,each of these three areas must be considered from an engineering perspective.First, in the process itself, classical chemical engineering is applied, includingreactor design, thermodynamics, unit operations, mass transfer, etc., which arewell established methods in the chemical process industry (CPI) The focus here

Super-is on the process, products, and profit The second area, the boundary of thefacility, is where the bulk of waste management is located, including recycle,reuse, treatment, source control, etc Lines of these two areas are blurred todaywith optimization of processes, recycle, and substitution of chemicals to minimizepollution However, both of these geographic areas are engineered and controlled

in terms of materials handling, processing, and safety, as would be found in anychemical process The third geographic area brings us to nature—the area aroundthe facility or waste site, where the fate and transport of contaminants releasedfrom the first two regions now takes control In the realm of environmentalchemodynamics (3), the controlling factors are the transport of chemicals in theenvironment, governed by the physical-chemical relationship to reaction, trans-port, etc Waste management in this region now involves sorption, sedimentoxygen demand, groundwater modeling, biodegradation, partition coefficients,and other multimedia processes The shift in understanding in this region issignificant We no longer have a reactor vessel, a temperature controller, or ahomogeneous catalyst bed The systems are heterogeneous, are difficult to scale,and may not provide consistent or reproducible results when management meth-ods or technologies are applied to a waste problem In addition to our lack of

control over these systems, problems faced are usually dealing with low levels ofcontamination, which are difficult to model, predict, or treat However, as riskassessment and exposure assessment methods improve in accuracy and realism,these problems are being tackled with growing frequency It is important torecognize in the natural environment that our efforts are usually secondary toexisting natural forces An excellent basis to approach management of waste, both

in the CPI model and beyond, in nature, is found in the Natural Laws, asillustrated below Also, a significant contrast develops when we look at theNatural Laws, especially if one compares them to the five elements in the federalapproach to management of hazardous wastes, as listed below:

1 Classification of hazardous waste

2 Cradle-to-grave manifest system

3 Federal standards for treatment, storage, and disposal (TSD) facilities

4 Enforcement with permits

5 Authorization of state programs

4 THE NATURAL LAWS

Dealing with waste falls under the Natural Laws (1,4) and it is from these lawsthat the waste management hierarchy is formed:

1 I am, therefore I pollute

2 Complete waste recycling is impossible

3 Proper disposal entails conversion of offensive substances into mentally compatible earthenlike materials

environ-4 Small waste leaks are unavoidable and acceptable

5 Nature sets the standards for what is compatible and for what are smallleaks

Briefly, these laws state the rules we must follow to properly manage waste inthe future Since we exist, we generate waste, and thereby pollute This is due tothe second law, which makes complete recycling impossible, as in thermodynam-ics, wherein no real process is completely reversible—some loss occurs Withsome waste therefore being generated, the third law requires that the material bereturned to the environment (nature) in a compatible format—that is, earth-enlike—in either a solid, liquid, or gaseous state When returned, small leaks willoccur, as with minor auto emissions, and these are unavoidable and acceptable,provided we observe nature’s standards as to what is compatible and how small(or large) the leaks can be A logical flow of management choices follows fromthese laws

5 WASTE MANAGEMENT CHOICES

The following list incorporates all options available and is similar to listsdeveloped by the EPA and others (5) The management list also supports therelationship presented by Reible (2) in that environmental impact is proportional

to population times per-capita resource usage divided by environmental ciency In words, then, the environmental impact is minimized for a givenstandard of living when the environmental efficiency is high or improved.Reible’s relationship supports the third law, to minimize impact via high environ-mental efficiency, returning material (and energy) in compatible forms It isimportant to note here that much of the waste discussion focuses on material, andthat energy pollution should not be neglected, due to problems found in changingriver temperatures due to discharge, global warming, etc To answer the oldquestion, “How clean is clean?,” a material is clean when it is returned in a form,amount, and concentration which is acceptable to that found in nature In otherwords, a material is “clean” when its concentration does not exceed the naturallimits of that material in the space established by the balances (material) thatassimilate it (6)

effi-Clearly, then, minimization is the first choice and the optimal one from anenvironmental standpoint However, society demands a certain standard of living,

so for those wastes remaining from minimization, destruction becomes the bestalternative Why destruction, as such a choice would support technologies such

as incineration? Because it is the molecular structure, among other things, thatprovides the toxicity of the compound, and if it can be broken down (hopefullynot yielding a more toxic compound), toxicity can be reduced or eliminated inefficient and correct incineration processes However, not all wastes causingtoxicity problems can be destroyed, such as heavy metals passing through anincinerator Thus, these materials must be properly treated prior to release,changing their chemical states or bonding for a less toxic or hazardous form.Finally, one notes that in all processes such as those above and others, someresiduals always remain, and lead to the final option, disposal Disposal requirescompliance with the Natural Laws—earthenlike materials acceptable to nature’sstandards for assimilation

Thus, the hierarchy for waste management is simply:

1 Minimization

2 Destruction

3 Treatment

4 DisposalWhile technologies may overlap these steps, all are contained within, whichbrings us to an important concept: how does natural attenuation fit into the wastemanagement scheme above? Natural attenuation, or monitored natural attenuation

(MNA), is at the front of waste management schemes for remediation of sites,coming into favor in the 1990s as a method to employ risk assessment withsource, pathway, and receptor models to decrease active remediation techniques(and associated costs) and increase passive technologies Clearly, budgets ofgovernments and industry cannot support active remediation technologies inorder to return contaminated systems to pristine conditions, and this has beenrealized through the use of MNA In reality, MNA is nothing more than ourunderstanding of the fifth Natural Law, and the standards set by nature What weare observing, understanding, and utilizing in MNA, coupled with active reme-dies, is simply our quantification of nature’s limits as to what it can assimilate.Our regulations tie in here with acceptable drinking water or use standards, alongwith artificial boundaries placed on problems, such as fence lines and our useneeds In any case, MNA provides treatment or destruction (reduction in toxicity)within the four choices for waste management.

Overall, choices for waste management within the hierarchy of tion, destruction, treatment, or disposal are best made on a risk-based approach,such as that expressed by Watts (7) For a site, or a waste management program

minimiza-at a facility or other problem, the key elements can be broken down into threecategories—sources, pathways, and receptors In this manner, a risk-based ap-proach may be taken by clearly identifying the sources and receptors, and thentesting the pathways for effect, which falls under the realm of chemodynamics,

as discussed earlier We find then that while government and industry are driven

by regulation and enforcement of waste management options, as with significantactive remediation in the 1980s, the trend is turning strongly now to a risk-basedapproach, within the Natural Laws, and by understanding the sources, pathways,and receptors, and the fate and transport of low-level contaminants in the biota

REFERENCES

1 W D Constant and L J Thibodeaux, Integrated Waste Management via the Natural

Laws The Environmentalist, vol 13, no 4, pp 245–253, 1993.

2 D D Reible, Fundamentals of Environmental Engineering, pp 10–12 Boca Raton,

5 C A Wentz, Hazardous Waste Management New York: McGraw-Hill, 1989.

6 W D Constant, L J Thibodeaux, and A R Machen, Environmental Chemical

Engineering: Part I—Fluxion; Part II—Pathways Trends Chem Eng., vol 2, pp.

525–542, 1994.

7 R J Watts Hazardous Wastes: Sources, Pathways, Receptors, pp 38–40 New York:

Wiley, 1998.

In many respects, pollution prevention and waste minimization are less creatures

of legislative fiat than are many other areas related to waste management In part,this is due to the way that the legislative and regulatory waste managementframework developed in the United States (1) In the United States, the majorregulatory strategy for addressing wastes, particularly hazardous or toxic wastes,

is a “command-and-control” system imposed upon the regulated community fromthe top down By contrast, many pollution prevention initiatives are voluntaryefforts initiated by companies that seek to improve the “bottom line,” rather thanrequirements imposed by a regulatory agency

To understand the current emphasis on pollution prevention, one must have

an understanding of the history of the regulation of hazardous and toxic wastes.Now that environmental management is maturing as a discipline, there is anincreasing recognition that pollution prevention and appropriate waste manage-ment (including minimizing waste streams wherever possible) during a facility’soperational life can greatly reduce the potential for costly remediation andcleanup after operations are discontinued

2.1 Love Canal and the Enactment of the Comprehensive

Environmental Response, Compensation and Liability Act (“Superfund”)

The Love Canal hazardous waste disposal site became the center of attention ofthe media, as well as the regulatory agencies, in the late 1970s and early 1980s,and inspired the passage of the Comprehensive Environmental Response, Com-pensation and Liability Act (CERCLA), also known as “Superfund.”

The Love Canal site was not originally constructed to be a waste disposalfacility Originally, the Love Canal was to be the centerpiece of a “model city,”and the use of the canal for waste disposal was not contemplated The canal wasoriginally constructed by William T Love at the easternmost edge of the town ofNiagara Falls, New York, in 1893 The canal was to be used to supply water togenerate a cheap and essentially unlimited supply of hydroelectric power for thismodel community The discovery and adoption of the use of alternating current

in the mid-1890s, which allowed electricity to be generated at some distance fromthe point where the electricity was to be used, rendered Love’s plans for the canaluneconomic, and Love’s dream for the canal was never realized The abandonedcanal filled with rainwater and was used as a swimming hole and for winter iceskating by the local community In the 1940s, Hooker Chemical Companyobtained rights to the canal, and began to use the old canal as a dump for chemicalwastes from Hooker’s chemical manufacturing operations Hooker Chemicaldrained the old canal, lined it with clay, and used the old canal as a waste dump.Between 1942 and 1953, an estimated 22,000 tons of chemical wastes, as well asmunicipal wastes, were dumped at the site When Hooker Chemical discontinuedactive use of the site, the company capped the old canal with a thick layer of clay,and covered the entire site with sod (3)

Hooker Chemical sold the dump site to the local board of education in 1953for a nominal sum (one dollar), on the condition that the company would not beliable for any problems related to the wastes that were disposed at the site Thoughthe board of education was aware that the site had been used for the disposal ofhazardous and toxic wastes, a school was constructed at the site, as werenumerous houses Though Hooker Chemical tried to stop the development on thecontaminated land, local governmental authorities ignored the warnings, andallowed the construction at and adjacent to the old disposal site