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Thermal Processing of Domestic Solid Waste Part 2 of 2 – Conversion Processes

Walter R. Niessen, P.E., B.C.E.E.


Course Outline

This second course in domestic solid waste technology assumes an understanding of chemistry and mathematics and presumes familiarity with combustion fundamentals and equipment through completion of the two-part Fundamentals of Combustion course and the Thermal Processing of Domestic Solid Waste –Part 1– Combustion course. This course includes:

This course includes a multiple choice quiz at the end, which is designed to enhance the understanding of the course materials.

Learning Objective

At the conclusion of this course, the student will:

Intended Audience

This course is intended for civil, environmental, mechanical and chemical engineers involved with or about to be involved with the incineration of municipal solid waste.

Benefit to Attendees

The course gives practicing engineers, regulators, and permit specialists the basic tools to understand the elements of domestic solid waste conversion systems.

Course Introduction

Purification by fire is an ancient concept, its applications for domestic solid wastes noted in the earliest chapters of recorded history. Modern application of these high temperature processes to achieve this end  reflect the increasing awareness by modern health and environmental professionals of the importance of effective sanitation; of the achievement of high levels of destruction of organic matter; and of the substantial neutralization of  the hazards associated with highly volatile combustible materials. However, for domestic waste, the primary focus is on volume reduction with the associated benefits in residue landfill requirements and residue hauling quantities and costs.

Often, engineers with little academic training in thermal processing facilities are thrust into assignments where this training gap becomes critical. This course, its predecessor and the course pair on Combustion Fundamentals provide an understanding of the waste and hardware characteristics for this important public works service.

Course Content

In this lesson, you are required to download and study the following course content in PDF format:

Thermal Processing of Domestic Solid Waste Part 2 of 2 – Conversion Processes

Please click on the above underlined hypertext to view, download or print the document for your study. Because of the large file size, we recommend that you first save the file to your computer by right clicking the mouse and choosing "Save Target As ...", and then open the file in Adobe Acrobat Reader. If you still experience any difficulty in downloading or opening this file, you may need to close some applications or reboot your computer to free up some memory.

Course Summary

This course attempts to answer the question:  How do the emerging “conversion technologies” differ from the more conventional “mass burn” or refuse-derived fuel (RDF) based municipal incinerator? In the early years of refuse incineration in the United States, incinerators were uncomplicated refractory furnaces equipped with metal grates and with (looking back) incredibly simple controls and inefficient air pollution abatement. The 1970's saw the emergence of a new incineration concept: high pressure, waterwall boilers that produced superheated steam that was fed to turbo-generators for power generation (Waste-to-Energy or WTE plants) and equipped with sophisticated process control systems and costly, highly efficient air pollution control. Although still developing, a new class of systems (the “conversion technologies”) is increasingly being offered as an alternative that avoids the generation of dioxin pollutants (a serious political and environmental problem faced by mass burn systems) and shows little or no heavy metal or acid gas emissions. In general, most of these technologies utilize either gas-burning turbines or direct firing in boilers to generate electricity or are configured to yield a synthesis gas ( a mixture of carbon monoxide and hydrogen) usable as a chemical feedstock.  Whether the benefit of improved air pollution is, in fact, sufficient to overcome the high cost and risk of these new technologies is to be seen.  However, it is clear that in technical, economic, environmental and/or political niches, these alternatives will be heard from in years to come.

The course begins with a review of the key characteristics of conversion technologies and the waste heating means that differentiates processes.  This is followed by a review of the process streams and sidestreams associated with this processing means followed by the options in conversion system designs now appearing in the marketplace..

Related Links

For additional technical information related to this subject, please visit the following websites:

American Society of Mechanical Engineers       http://www.asme.com/     
Air and Waste Management Association         http://www.awma.com/
Combustion Engineering Association              http://www.cea.com.uk/

Quiz

Once you finish studying the above course content, you need to take a quiz to obtain the PDH credits.

Take a Quiz

DISCLAIMER: The materials contained in the online course are not intended as a representation or warranty on the part of PDH Center or any other person/organization named herein. The materials are for general information only. They are not a substitute for competent professional advice. Application of this information to a specific project should be reviewed by a registered architect and/or professional engineer/surveyor. Anyone making use of the information set forth herein does so at their own risk and assumes any and all resulting liability arising therefrom.