ILSR Advises Hawaii to Avoid Solid Waste Combustion as a Waste Management Strategy

Memorandum on Gasification and Pyrolysis May 2021

When widespread rollbacks in recycling programs throughout Hawaii led to renewed calls for waste-to-energy, Recycle Hawaii commissioned ILSR to analyze the status of technologies promoted as environmentally friendly. This memorandum highlights the findings of that analysis, which drew on the expertise of specialists familiar with pyrolysis and gasification technologies and also reviewed relevant trends as a means to create a context for Hawaii-based policy makers. Recycle Hawaii, ILSR and Zero Waste Associates are also collaborating on an update of the Zero Waste Plan adopted by Hawaii County in 2009 that was originally prepared by Richard Anthony Associates in conjunction with ILSR.

Prepared for Recycle Hawaii by Waste-to-Wealth Initiative Institute for Local-Self-Reliance, Washington, DC

Municipal Waste Combustor Feasibility Assessment

The Institute for Local Self Reliance (ILSR) prepared this assessment of gasification and pyrolysis technologies as feasible waste management options for Hawaii County in response to a request from Recycle Hawaii. Its conclusion is based on research as well as input gathered from waste management professionals and zero waste experts. In reaching this conclusion, technological readiness was considered on a par with the impacts that adoption of these, or any incineration technology, would have on the county’s long-term waste reduction goals. This assessment is part of a broader scope of work conducted by Recycle Hawaii, Zero Waste Associates and ILSR to update the Hawaii Island Zero Waste Plan originally adopted in 2009.

Technology Characterization

“Waste-to-energy” is a term commonly used to emphasize the energy production aspect of technologies that recover it from waste. Use of the term also serves to create a broader category within which distinctions can be made between early and advanced technologies by classifying some as incinerators and others according to the processes they use, such as gasification and pyrolysis. Instead of using this unscientific term, this assessment conforms to the EPA practice of 1) characterizing all technologies that ultimately combust municipal waste as “municipal waste combustors” regardless of whether this is achieved in a 1-stage or 2-stage process, and 2) treat- ing this term as synonymous with “incinerator.” According to the EPA, gasification and pyrolysis are best described as 2-stage incinerators.

State of the Art Survey

Throughout the U.S., numerous companies are actively promoting municipal waste combustion as a means to address the impacts caused by shifts in Asian recycling markets. The development strategy commonly employed in this effort involves securing federal funds and tax incentives to cover the costs of small-scale pilot projects designed to produce results that will justify design/ build/operate contracts for handling much larger volumes of waste.

Heinz Weverink, principal of Leftover Recycling Services, has been on the frontlines of the waste management industry for nearly 50 years. During this time he managed solid and liquid waste operations as well as recycling companies and served as an enforcement officer for the state of Maryland. Weverink has been involved in the development of numerous recycling and waste management facilities around the country, including the GenAgain facility for Agilyx, a chemical recycling project that took over five years to get operational.

Although he is a strong proponent of both gasification and pyrolysis in theory, Weverink attests from first-hand experience that major project failures and the need for significant subsidization have prevented these technologies from advancing beyond the pilot project stage. He further asserts that the high costs associated with developing such projects at a time when all branches of government are struggling to cope with COVID-19 makes this approach to solid waste management unaffordable. Weverink cautions against partnering with relatively unproven players, and the advice he gives municipalities considering this option is to base their decisions on the benefits of gasification or pyrolysis as solid waste processing systems rather than a means to produce fuels, which need additional refinement and are not ready for gas tanks or generators with- out additional costs and effort. His assessment of these technologies is that the industry must solve numerous complex problems for them to work. Weverink’s major concerns are summarized below:

  1. Equipment providers routinely oversell the capabilities of their equipment;
  2. Chlorine is a common element found in municipal solid waste, and handling it requires the use of stainless steel, which adds significantly to the capital cost as well as the costs of treating residue;
  3. Plastic components, such as styrenes, degrade the value of the fuel produced;
  4. Residues formed by non-vaporized material become cadmium-based char, to be disposed of at great cost;
  5. Advanced technologies like pyrolysis and gasification work best with homogeneous feedstocks;
  6. Handling the inflow of heterogenous material is critical and problematic.

Incineration Defined

Both the European Union and the United States Environmental Protection Agency (EPA) define gasification and pyrolysis as a type of incineration.

The U.S. EPA federal regulation 40 CFR 60.51a states: Municipal waste combustor, MWC, or municipal waste combustor unit: (1) Means any setting or equipment that combusts solid, liquid, or gasified MSW including, but not limited to, field-erected incinerators (with or without heat recovery), modular incinerators (starved-air or excess-air), boilers (i.e., steam-generating units), furnaces (whether suspension-fired, grate-fired, mass-fired, air curtain incinerators, or fluidized bed-fired), and pyrolysis/combustion units. Municipal waste combustors do not include pyrolysis/combustion units located at plastics/ rubber recycling units (as specified in § 60.50a(k) of this section). Municipal waste combustors do not include internal combustion engines, gas turbines, or other combustion devices that combust landfill gases collected by landfill gas collection systems.

Weverink points out that after 14 years of experimenting with chemical recycling, Agilyx is adapting by repurposing their equipment and processes to deliver a system that processes styrenes, a single plastic type, rather than the mix of plastics typically found in solid waste.

Richard Aho, principal EMS, LLC, is an engineer with 35 years of integrated solid waste man- agement experience, during which time he has worked extensively with the pyro-processing of industrial minerals and energy production from waste feedstocks. Aho agrees with Weverink’s assessment and adds the following observations:

“Start ups, shut downs, and fluctuation in the BTU values of the feedstock/fuel can easily create toxic emissions such as dioxins or furans. The issues of balancing a gas production sys- tem, an emission control system, and wide variation in fuel quality and contamination is difficult to quantify. A blast furnace has consistency with minimal variation in quality and quantity of fuel and inert (nontoxic) feedstock. An emission control and monitoring system is based on a tight set of operating parameters. Using solid waste as both fuel and feedstock is never going to be consis- tent. The introduction of multiple unknowns into the process can easily disable the emissions con- trol system at the worst possible time for the downwind stakeholders. What protections would be in place, particularly for the at-risk members of the community?

With “unplanned” feedstock, catastrophic failure of the gasification system is possible. From an operational standpoint removing partially burned solid waste from a blast furnace would be very unpleasant and would probably require significant downtime/repairs. What contingencies are in place when the gasification system has been destroyed or damaged by the feedstock? The damage associated with failures could be catastrophic from the structural, safety, explosive/toxic gas, and sensor/monitoring perspectives. What safeguards are being proposed to address the introduction of multiple, fundamental variables into the overall process?”

Mike Ewall of Energy Justice Network has done extensive research on incineration technologies. He explains that all combustion is technically gasification.

“If you light a piece of paper on fire, and look closely, you’ll notice a gap between the pa- per and the flame. It’s the heat that gasifies the paper, and the gases that burn. This takes place in any sort of incinerator. However, in 2-stage incineration processes, like gasification and pyrolysis, this process is broken into steps, and is essentially like putting a pipe between the paper and the flame. The first stage turns the feedstock into a gas, which then gets burned in a second stage. Claims that gasification and pyrolysis are not incineration or do not involve combustion depend on a limited analysis that focuses on the first stage and ignores the second.”

When assessing the feasibility of municipal waste combustors, Ewall points to recommendations made by leading industry experts who assist with their development, such as the pro-incineration consulting firm, Gershman, Brickner & Bratton, Inc. (GBB). GBB characterizes both gasification and pyrolysis as high-risk investments due to “previous failures at scale” and “no operating experience with large-scale operations in the U.S.”2  GBB has continuously presented variations of this high-risk assessment for the past decade, as these technologies are relegated to small-scale demonstration plants that typically fail technically and/or economically. Plants that continue to operate do so by abandoning mixed municipal solid waste and switching to homogeneous feedstocks.




In 2011, Prince George’s County, Maryland hired GBB to review alternatives to landfilling. After extensive analysis of options including municipal solid waste combustion, gasification, waste-to-fuels, and mixed waste processing, GBB narrowed the list of qualified vendors from 16 to seven before Prince George’s County abandoned all of them in 2016 in favor of a plan to extend the life of its landfill and adopt zero waste measures. Vendors with gasification technologies did not make the short-list of seven.

In 2014, the world’s largest waste corporation, Waste Management, Inc., sold off its investments in gasification, pyrolysis and other waste-to-fuels companies.3

In June 2020, consultant Geosyntec completed a $450,000 Solid Waste and Recycling Master Plan for the City of Baltimore, which looked at options for replacing its aging trash incinerator. Their final report states:

Gasification is also an emerging and untested technology for waste processing in the U.S., which may make it difficult to permit and build such a facility. Based on the very high capital costs for a MWP facility using gasification technology, and the fact that gasification is a largely untested technology for processing organics separated from a mixed waste stream, a MWP facility configuration with a gasifier is not recommended.4

MWP stands for mixed waste processing, which involves sorting trash to remove materials such as glass and metal before preparing what remains to be burned, composted or digested. Although proponents of gasification and pyrolysis claim these technologies can effectively process a wide variety of materials, they cannot process them as a heterogenous mixture. Extensive use of MWP is required to produce an acceptable feedstock and even when such sorting methods are in place, what comes off the back end is often still too diverse for the highly sensitive mechanical components that comprise these systems.

In their more detailed “Managing What’s Left” report leading up to the Master Plan, Geosyntec elaborates on gasification, stating:

“Geosyntec is not aware of any commercial scale MSW gasification project currently in operation in the U.S. It is not a mature technology and thus analyses presented in this section are based on extrapolation from pilot projects that may not be scalable or projects currently under construction (which are unproven). This adds an extra dimension of uncertainty to the findings discussed here.” 5

Geosyntec goes on to describe how gasification would compete with waste reduction efforts and face political challenges from an environmentally-concerned public:

Permitting and acceptance: Gasification is an emerging and untested technology for waste processing in the U.S. As such, it may be difficult to permit and build such a facility. Further, government agencies and the public may be skeptical of the benefits of gasification.6

There have been many proposals for waste pyrolysis in the U.S., with the vast majority of them resulting in failure, including the ones listed below:

  • Atwood, Indiana
  • Logansport, Indiana
  • Baltimore, Maryland
  • Bordentown, New Jersey
  • New York, New York
  • Niagara Falls, New York
  • Pearl River, New York
  • Cleveland, Ohio
  • Chester, Pennsylvania
  • Crawford County, Pennsylvania
  • Houston, Texas
  • Burlington, Vermont

Pyrolysis is a process that involves the thermal decomposition of materials in an inert atmosphere. Because pyrolytic systems operate at lower temperatures than conventional incinerators or gasifiers, they produce a broader range of byproducts from incomplete combustion, including highly toxic and carcinogenic chemicals such as tars, dioxins, furans, and polycyclic aromatic hydrocarbons (PAHs).

A standard claim in favor of pyrolysis is that the process cannot form dioxins and furans because these substances “are formed when organic matter and materials containing chlorine are burned in the presence of oxygen at very high temperatures.”7  In fact, dioxins and furans are formed at temperatures within the range at which pyrolysis takes place (as low as 350—400°C), and the fact that the syngas coming out of the pyrolysis chamber contains roughly 20% oxygen by molecular weight demonstrates that even though the process does not introduce outside air, there is more than enough oxygen in the feedstock to combine with hydrocarbons and halogens to form these extremely hazardous substances.

Another common pitch made for pyrolysis is its effective-ness as a means for processing scrap tires, but the Rubber Manufacturers Association (a trade association that sup-
ports using tires as an energy feedstock), has reported that: “Major tire companies like Goodyear and Firestone once invested ‘immense resources’ in pyrolysis but could not find markets for the byproducts or even a way to integrate them into their own products. And scores of start-ups have tried and failed to make money from tire pyrolysis. . . The road is littered with the carnage of people who were trying to make this technology viable.”8

The U.S. Environmental Protection Agency states that: “While technically feasible, tire pyrolysis— a process in which tires are subjected to heat in an oxygen-starved environment and converted to gas, oil and carbon char—has been inhibited by the high capital investment required and steep operating costs.”9

Pyrolysis is also used to produce biochar from carbon rich materials like wood, wood waste, and agricultural waste. While promoted as a carbon sequestration strategy, biochar production results in toxic byproducts that are often ignored.10

Existing emissions data on pyrolysis plants shows that air emissions from them can be comparable to, or even more polluting than, trash incinerators, which are dirtier than coal power plants by most measures and proven to be the most expensive and polluting way to manage waste.11

New limited liability corporations bring most pyrolysis proposals forward with no track record of technical or financial success; their claims about the lack of emissions are misleading, and are sometimes accompanied by the use of promotional designs that do not include smokestacks.

Like waste gasification and plasma arc facilities, pyrolysis plants are typically designed to process small batches at demonstration scale. There are currently no pyrolysis plants operating continuously at commercial scale using municipal solid waste as a feedstock.

Four other sources of information on gasification and pyrolysis technology are relevant to Hawaii County’s needs. The Global Anti Incineration Alliance prepared “Waste Gasification & Pyrolysis: High Risk, Low Yield Processes for Waste Management—A Technology Risk Analysis” in 2017 (a report that covers worldwide developments of these technologies)12 and “All Talk and No Recycling: An investigation of the U.S. ‘Chemical Recycling Industry,” July 2020.13

Among other important facts to note is that in Japan, the country with the most experience with solid waste gasification, the number of gasification plants declined from 1,800 to 1,200 in recent years.14

Zero Waste Europe issued “European Incineration Myths,” July 2020. This document summarizes the variety of measures recently taken to discourage investment in all future solid waste incinera- tion technology.15

Jack Buffington, Research Professor & Associate Director Mack-Blackwell National Rural Transportation Study Center, College of Engineering, University of Colorado and recent author of “Peak Plastic: The Rise or Fall of our Synthetic World,” encourages the industry to develop non-thermal repolymerization of plastic discards, not thermal repolymerization, or incineration.

Professor of Chemistry (retired) Paul Connett, provided a detailed assessment of solid waste incineration in a lecture to the citizens of New York’s Warren and Washington Counties that covers the many issues surrounding incineration technologies.16 Connett’s message underscores the need to capture organic matter and produce compost for local food production while also pursuing recycling as a means to create local jobs. High technology systems employ chemical engineers but they do not create jobs for regular workers; whereas recycling, composting and reuse are labor intensive.

Another area of concern relates to the need for sustained waste generation at a time when Earth’s natural resources are being depleted. Financing the high capital costs of municipal waste combustors requires a guaranteed flow of income, which is dependent on a guaranteed flow of waste. When governments are involved in incineration projects, taxpayers are held liable for costs incurred when the flow of waste drops below the guaranteed level. Recent costs to Oahu taxpayers as a result of a decrease in deliveries to H-Power provide a pertinent example. In 2017, the City and County of Honolulu fell 49,000 tons short of the volume it had agreed to deliver, which left Oahu taxpayers with a nearly $600k-bill to cover the losses Covanta incurred when it failed to provide power to the utility.

At a time when major retailers are vowing to reduce the volume of waste they generate and investments in recycling infrastructure are driving the expansion of a domestic industry in the U.S., making a long-term commitment to provide large volumes of waste to incinerators cannot be justified.

Summary and Conclusion

Based on ILSR’s research, municipal solid waste combustion does not offer a feasible waste management option for Hawaii.

ILSR found sufficient information from correspondence with academic, government, industry and public interest sources to determine that both gasification and pyrolysis have failed to live up to the promise of a cost effective and nonpolluting technology.

Recycling and composting have always been the preferred strategies for handling discarded items that cannot be reused, and incineration technologies, no matter how advanced, and re- gardless of whether they outsource the combustion aspect by producing fuels, undermine ef- forts to reduce waste. Rather than anticipate advancements that might someday make gasification or pyrolysis technologies acceptable, ILSR recommends that the county take immediate action to improve existing infrastructure in ways that take advantage of high drop off rates to produce a steady stream of clean, high quality discards.

By making these improvements and working with international secondary materials brokers and companies capable of processing materials for reuse on island—through composting, anaerobic digestion, small scale recycling and reuse enterprises—Hawaii County can achieve the environmental and economic goals set forth in its general and community development plans as well as its climate action initiative and zero waste plan.

1 Dioxin Homepage,

2 “Waste Conversion Technologies for Minnesota,” GBB presentation to SWANA, October 17, 2017. See slide 30 in; See also, slide 43 in “The Latest Updates on Waste-to-Energy and Conversion Technologies; Plus Projects Under Development,” GBB presentation to WasteCon 2012. WASTECON2012.pdf

3 Big Waste Hauler Rethinks Startups,” Wall Street Journal, Jan 3, 2014.

4 “Draft Master Plan, City of Baltimore, Recycling and Solid Waste Management Master Plan,” Geosyntec, June 2020. See pages 57 and 60: LWBB_Draft%20Master%20Plan_6-5-20.pdf

5 “Managing What’s Left, City of Baltimore, Recycling and Solid Waste Management Master Plan,” Geosyn- tec, April 2020. See page 36: FINAL4-15-20.pdf

6 Id. at 38

7 “Responding to concerns about dioxins,” Op Ed by Alvaro Almuina (Project manager, Pyrolyzer, LLC), Lo- gansport, Indiana Pharos-Tribune, April 24, 2013.

8 and web/20100403061338/

9 and web/20100403061338/

10 See reports by Biofuelwatch on Biochar:

11 “Incineration and Incinerators in Disguise,” Energy Justice Network.

12 cesses-march-2017.pdf


14 All Talk and No Recycling: An Investigation of the US “Chemical Recycling” Industry—Global Anti Incineration Alliance, July 2020

15 European Incineration Myth: Current Trends—Zero Waste Europe, July 2020 16



Photo credit: Unsplash

Avatar photo
Follow Neil Seldman:
Neil Seldman

Neil Seldman, Ph.D, directs the Waste to Wealth Initiative. He specializes in helping cities and businesses recover increasing amounts of materials from the waste stream and add value to the local economy through new processing and manufacturing facilities. He is a co-founder of the Institute for Local Self-Reliance.