Handbook of Environmental Engineering: Vol. 7 Biosolids Engineering and Management

Citation

(2009), "Handbook of Environmental Engineering: Vol. 7 Biosolids Engineering and Management", Management of Environmental Quality, Vol. 20 No. 2. https://doi.org/10.1108/meq.2009.08320bae.001

Handbook of Environmental Engineering: Vol. 7 Biosolids Engineering and Management

Handbook of Environmental Engineering: Vol. 7 Biosolids Engineering and Management

Article Type: Books and resources From: Management of Environmental Quality: An International Journal, Volume 20, Issue 2

Lawrence K. Wang, Nazih K. Shammas and Yung-Tse Hung,Humana Press,Totowa, NJ,2008,800 pp.,EISBN 978-1-59745-174-1,US$175

This book, Vol. 7, in the series of the Handbook of Environmental Engineering “is a sister book to Vol. 6, Biosolids Treatment Processes (reviewed in MEQ Vol. 19 No. 3, 2008, pp. 402-5). Both biosolids books have been designed to serve as basic biosolids treatment textbooks as well as comprehensive reference books”. Vol. 7 comprises 13 chapters of unequal extension (ranging from 123 pp. to 26), with a lengthy appendix (43 pp.) on conversion factors for environmental engineers, written by a set of 16 authors from 3 continents (America, Africa and Asia). However, in nine chapters and the appendix at least one of the editors is author or co-author. This tends to give a unity of purpose to the enterprise. Physically, the book is not easy to handle with a weight of circa 4 lb (1.3 kg) and dimensions 25 × 16 × 5 cm (9.84 × 6.30 × 1.97 in). It should be mentioned that the heaviness is a reflection on the abundant content, good paper quality and excellent binding, although it is hard to read away from the desk (certainly not by a lector in recumbent position!).

A fundamental difficulty in trying to present quantitatively civil and environmental engineering is that we are faced with the problem of using a consistent system of units. The authors have used the British system along with the metric equivalent, the latter unfortunately variedly presented as mks, cgs or SI. When the world of science has adopted the SI of units for many years, this book exhibits an atavistic trend. Furthermore, there is ambiguity as to the use of “sec” or “s” as the symbol for second.

Since disposal into oceans, rivers and lakes is no longer thought as appropriate, the companion book, volume 6, did cover issues on biosolids characteristics with a view to utilization in land disposal. Owing to the extension of the present Vol. 7 it is impossible to comment in detail on the contents of each chapter, so I shall simply list the chapters’ titles as a guide to the different topics dealt with and shall add a few relevant comments when deemed pertinent. The chapters’ titles are:

Transport and pumping of sewage sludge and biosolids; Conversion of sewage sludge to biosolids; Biosolids thickening-dewatering and septage treatment; Waste chlorination and stabilization; Storage of sewage sludge and biosolids; Regulations and costs of biosolids disposal and reuse; Engineering and management of agricultural land application; Landfill engineering and management; Ocean disposal technology and assessment; Combustion and incineration engineering; Combustion and engineering management; Beneficial utilization of biosolids; Process selection of biosolids management systems.

If “[s]ewage sludge can be described as a complex mixture of suspended and dissolved inorganic and organic materials”, then biosolids “is the new name for what had previously been referred to as stabilized sewage sludge. Biosolids are primarily organic treated wastewater residues from municipal wastewater treatment plants…that are suitable for recycling as a soil amendment”.

The emphasis throughout the text is on recognizing that engineering practice is now more firmly entrenched in scientific principles than in an empirical accumulation of facts. Thus wide use is made of principles and rules of chemistry, microbiology, physics and mathematics. Throughout the chapters, practical design criteria, calculations and staffing requirements are illustrated with numerical examples. “These examples clearly demonstrate how organized, analytical reasoning leads to the most direct and clear solutions. Whenever possible, pertinent cost data have been provided”.

When it is de riguer necessary to solve a problem for a topic under discussion, as for instance in chapter 2 to control offensive odors (sulfur, mercaptans, ammonia, amines and organic fatty acids emanated from proteins, amino acids and carbohydrates present in the sludge), specific and detailed instructions are given. Sometimes a description is all encompassing, in fact an overkill, like the meticulous listing of types of vehicles described for hauling sludge/biosolids, that is, among them “two- or three-axle truck [lorry for British readers] with a two- or three-axle trailer” preferably with a diesel engine powered, or the detailed description of barges and tugs’ sizes and dollar costs.

Since workers who have direct contact with biosolids are likely to have an exposure to pathogens, compounded by poor hygiene and raw sewage, these persons should be well instructed as to wear dusk masks, gloves and do routine hand washing before eating, drinking, smoking and before and after visiting the restroom [toilette for British readers].

Procedures and machinery therefor are described in full detail with numerous illustrations, for instance in the application for sludge thickening reference is made to different techniques: gravity thickener, countercurrent solid bowl centrifuge, basket centrifuge, rotary drum unit, belt filter press, etc.

Once septage is defined as “the liquid and solid material pumped from a septic tank or cesspool when it is cleaned”, a wide selection of recent processing methods that offer promising applications is presented, i.e. Expressor Press, Som-A-System, CentriPress, etc.

The usage of chlorine provides an efficient disinfectant as well as an oxidizing agent employed most frequently by scientists and environmental groups since the 1800s. The process of adding chlorine to any liquid or semiliquid medium is called chlorination; when chloramines are used the process is termed chloramination. Attention is drawn to the fact that chlorine may be fatal if inhaled in sufficient quantity [(1,000 ppm (parts per million)], but very low concentrations like 3.5 ppm are easily detectable and irritation of the nasal lining shows at 15-30 ppm. Again, detailed instructions are given to deal with the precursors of chlor(am)ination.

The United States Environmental Protection Agency (US EPA) and US Department of Agriculture (USDA) guides to the treatment of biosolids are abundantly invoked. A full chapter (number 6) is devoted exhaustingly to discussing the US federal standards for the use or disposal of biosolids [Title 40 of the Code of Federal Regulations (CFR), Part 503].

Of special interest is chapter 7 on the controlled application of sludge biosolids to cropland by subsurface injection or surface spreading. Every step is included: from design criteria to costs and trouble shooting guide.

Indiscriminant dumping into the ocean, practiced worldwide, was carried out as late as 1970, under the attitude that “the ocean had unlimited resources and an unending capacity to absorb impact” (chapter 9). These assumptions were proven to be wrong. However, if “done in an environmentally acceptable manner, disposal at sea can be an attractive option, since it is generally less expensive than other waste management options such as waste treatment of land disposal. The London Convention 1972 and the London 1996 Protocol have essentially banned the disposal at sea of all waste an other matter other than the wastes listed in the Annexes to the convention.” Nonetheless, “ocean disposal should be the last option if the wastes can be recovered for beneficial use”. The progression in the disposal of biosolids in the city of Los Angeles in California is presented as an example: the biosolids produced at a treatment plant were disposed in the ocean from 1957 to 1987, between 1987 and 1989 they were primarily disposed on landfills. From then on the city started an extensive beneficial reuse program (100 percent in 1994) which is continuing today and for which Los Angeles has received special recognition and awards.

As trivia the reader may learn that the tread in automobile tires is made from two types of styrenebutadiene rubber while the sidewalls are a mixture of natural rubber and polybutadiene rubber. When subjected to incineration they have different kinematic parameters as studied by Soviet authors referenced in the text. In pyrolysis the objective is the thermal decomposition of carbonaceous solids in the absence of air to obtain in this way “gaseous and liquid fuel products suitable for firing in conventional combustors”. Cellulose pyrolysis is mentioned to begin circa 200°C, that converted gives 392°F, not so close to “Fahrenheit 451”, title of a widely read science fiction book based on the temperature at which paper burns, although perhaps the latter was not a pyrolytic decomposition.

Air pollutant emissions are central points of public concern and regulating scrutiny in the case of incinerations. The pollution contributions from different combustion processes are analyzed: inorganic particulate matter, volatile organic compounds, the still unresolved effects of dioxine emissions (from incineration furnaces), etc. The incineration of biosolids as an energy source is given a few paragraphs. It is noted that the “energy value of methane generated from the anaerobic digestion process exceeds the energy requirement of the digestion process. The excess can be used to supply the energy needs of other plant processes” or of the entire wastewater treatment plant with excess gas still available for sale:, e.g. British Southern and Mogden plants, the county sanitation districts of Los Angeles and of Tampa, Florida. The State of California has directed the state electric utilities to increase cogeneration projects. In this context cogeneration means production of power by utilizing waste heat.

“For the convenience of the readers around the world, this book provides a detailed Conversion Factors for Environmental Engineers” as well as “important physical constants, the properties of water, and the Periodic Table of the elements”. In the lengthy conversion tables all kinds of units are revealed: barrels, BTU, bushels, carats, chains, circumferences of both 360 degrees and of 400 grades, pica (in printing), etc.

There are a few errors or omissions: in p. 91, Table 2.10 the column for “D/T” referring to odor units I could not find a definition; in p. 203 the uninitiated will not know the meaning of the “Imhoff tanks”; in p. 492, Figure 10.3a the numbers indicating chemical reaction for different reactants have been clipped off from the left side of the illustration and B as a subtitle is misspelled as “C” (repeated!); in p 499 the citation in text number 11 is attributed to two different authors’ teams; in p. 529 Fig 10.11, describing the Detroit stoker reciprocating grate furnace system, the identifying ciphers in the figure legend have been omitted on the actual figure resulting in an illustration practically worthless; in p. 785 “metor” is supposed to mean meter. The ambiguity in the use of units, or symbols thereof, is the most salient in p 787 where in the same Table 4 the abbreviation for “second” is given some times as sec, others as s. In Table 5 the properties of water as function of temperature are given only for °F. In p. 788, Table 6 for the Periodic Table the character “I” (capital I) is employed instead of “l” (lower case l), so that Cl and Tl, for instance are symbolized as “CI” and “TI”…rather confusing.

In pointing out the errors, their presence almost unavoidable in a book of such magnitude, I do not want to detract from its value. For each procedure or modality of biosolids treatment the purpose of a system, the listed specifications, the theoretical considerations, the necessary equipment, the operation and maintenance, the costs in power sources and number of staff, and the advantages and disadvantages of the procedure are discussed at length and in easy language. Realistic case studies are analyzed in minutiæ. When there is a mathematical analysis it is always done with extreme clarity and step by step.

In this Handbook there are many references at the end of each chapter listing complete titles and all authors for each publication including some from 2007. There are multiple illustrations both tabular and pictorial in black and white. There is an alphabetic subject matter index at the end of the book. It would have been helpful to have a complete alphabetic list of abbreviations used in the text.

The editing authors recommend this book, Biosolids Engineering and Management, with its sister Volume 6, Biosolids Treatment Processes, as “basic biosolids treatment textbooks as well as comprehensive reference books. We hope and expect they will prove of equally high value to advanced undergraduate and graduate students, to designers of wastewater, biosolids, and sludge treatment systems, and to scientists and researchers”. My humble comment is that the volumes are excellent as reference books, but they will need a very experienced, prudent, judicious and compassionate teacher to obtain allegiance from the students if used as textbooks on account of their prolixity.