ABSTRACT
Written by noted experts in the field sharing extensive academic and industrial experience, this thoroughly updated Second Edition covers commonly used and new suspended and attached growth reactors. The authors discuss combined carbon and ammonia oxidation, activated sludge, biological nutrient removal, aerobic digestion, anaerobic processes, lago
TABLE OF CONTENTS
part |2 pages
Part I
chapter 1|16 pages
Classification of Biochemical Operations
of wastewater treatment is to remove pollutants that can harm the if they are discharged into it. Because of the deleterious effects of low dissolved oxygen (DO) concentrations on aquatic life, wastewater treatment of pollutants that would deplete the
chapter 2|12 pages
Fundamentals of Biochemical Operations
of biochemical operations, it is necessary to of what wastewater treatment engineers hope to accomplish if we are to develop the capability for their design,
chapter |30 pages
of Anaerobic Operations. The multistep nature of anaerobic
biochemical operations is depicted in Figure 2.3. Before insoluble organic materials can be consumed, they must be solubilized, just as was necessary in aerobic systems. Furthermore, large soluble organic molecules must be reduced in size to facilitate transport across the cell membrane. The reactions responsible for solubilization and size reduction are usually hydrolytic and are catalyzed by extracellular enzymes
chapter |26 pages
r---r----r---r--"T"""---r--"""?----.-----.-----..--
0.207 = 0.50 20 mg/L 0.20 K= 40 mg/L 0: 0.15
chapter |5 pages
+ V state to the -
III state, and thus those electrons are incorporated into the biomass even though they will not be measured in the COD test. This is because nitrogen does not accept or give up electrons in the COD test. Consequently, if biomass is represented by CHON, its COD must be multiplied by 1.4 for the balance to work, as suggested by Eq. 3.17. Thus, to generalize: COD removed = 0 equivalents of terminal electron acceptor used
chapter |5 pages
of Particulate and High Molecular Weight Organic Matter. As
on the effects of temperature on the hydrolysis of particulate substrate. it is an enzymatic step, the hydrolysis coefficient, kh, is likely to of experimental data to sim- of temperature on of the effects of temperature on other processes, such as phosphorus
chapter |9 pages
(0must be
provided per mg of COD removed for each of the following situations? What quantities of micronutrients will be required? Do not derive the stoichiometric equations. Rather, answer the question using generaliza- tions presented in the text. 0.70 mg biomass COD formed/mg substrate COD removed.
part |2 pages
Part II
chapter 4|3 pages
Modeling Suspended Growth Systems
we saw that many types of biochemical operations are used in waste- be a difficult task if we of com- of events occur within them,
chapter |7 pages
Influent Effluent Volume= V
of A in the influent and effluent (or reactor), respec- Chas been used here to emphasize the of its state, i.e., soluble or particulate. For the systems with which we deal it is safe
chapter |37 pages
+ fo·bH·Xs,H·V 0
(5.22) Rearrangement gives: X = f ·b •@ ·X = (®c) [fo·bH·@c·YH(Sso - Ss)] H c T l (5.23) The units of Xwill be the same as the units of Xs,H• Debris adds to the total suspended solids concentration in the bioreactor, but does not add to the degradative (5.25) + bH·T The active fraction of the biomass, is defined as the concentration of active biomass divided by the total biomass concentration. Division of Eq. 5.19 by Eq. 5.24 and rearrangement yields: + fo·bH·@c
chapter 6|16 pages
Multiple Microbial Activities in a Single Continuous Stirred Reactor
Tank In Chapter 5, we investigated the growth of aerobic heterotrophic bacteria in a single continuous stirred tank reactor (CSTR) receiving a soluble substrate. Through de- velopment of a simple model we saw that the SRT is an important determinant of
chapter |8 pages
It will be recalled that the
specific growth rate is controlled by the soluble substrate concentration, as expressed by the Monad equation (Eq. 3.36). Since the soluble substrate concentration is var- ying over time, so is the specific growth rate. This means that the bacteria are in a continually changing state. For the reactor configuration in Figure 5.1, the SRT is determined solely by the reactor volume and the wastage flow rate. Consequently,
chapter |16 pages
+ b · )Y ]
(6.2) where represents the ammonia-N concentration in the feed that is available to the nitrifiers, i.e., the amount remaining after consideration of the amount used by the heterotrophs for biomass synthesis. fis 0.20, the destruction of 100 g of biomass COD will lead to the release of 20 g of biomass debris COD and the consumption of 80 g of oxygen. As reflected by and iNixo, the nitrogen contents of biomass and biomass debris are around 0.086 and 0.06 g N/g biomass COD, respectively. Consequently, destruction of 100 g of biomass will also lead to the release of 7.4 g of ammonia- (100[0.086-(0.20 · 0.06)]), which can act as substrate for autotrophic bacteria.
chapter 7|9 pages
Multiple Microbial Activities in Complex Systems
of microbial cultures in single contin- of solids reten- of some industrial wastewaters, more
chapter 8|8 pages
Techniques for Evaluating Kinetic and Stoichiometric Parameters
of Part II, we have examined models for characterizing of ideal suspended growth bioreactors. Before those models can be of wastewater treatment systems, however, values
part |2 pages
Part Ill
chapter 9|10 pages
DESIGN AND EVALUATION OF SUSPENDED GROWTH PROCESSES
Growth of this book addresses the technical aspects of the design and evaluation of of designing and evaluating such operations, with
chapter |22 pages
Theµ values for the PAOs are lower than those of ordinary heterotrophic
bacteria, which are not capable of accumulating phosphorus. Consequently, the lower limit on the SRT for phosphorus removal is generally higher than that for soluble substrate removal. On the other hand, the lower limit on the SRT for phosphorus removal is similar to the lower limit for nitrification, suggesting that it may be difficult to operate a bioreactor for phosphorus removal without experiencing the
chapter 10|34 pages
Activated Sludge
of bioreactor configurations for the of removing soluble organic matter. It is a flexible, reliable process capable of producing a high quality effluent. Soluble organic matter is reduced to low levels,
chapter |8 pages
If of
if the wastewater contains a high of colloidal organic matter that can be removed by entrapment in the
chapter |7 pages
of Volume, Mixed Liquor Suspended Solids, and Oxygen in Non-
of biomass and the total oxygen requirement in the various alternative activated of Chapter 5 as modified in Section of flows or volumes into
chapter |3 pages
= = glm =
Ss)] = + + of XM,r V, no term is included of the autotrophic bacteria. If their contribution to the waste
chapter 11|8 pages
Biological Nutrient Removal
Biological nutrient removal (BNR) processes are modifications of the activated sludge process that incorporate anoxic and/or anaerobic zones to provide nitrogen and/or phosphorus removal. Many variants have been developed, representing a wide range of nutrient removal capabilities. This chapter presents the basic design and operational principles for several of them. It builds upon the theoretical concepts
chapter |2 pages
[FeiP0
0]. The process designer must be of these potential impacts and balance the requirements of the liquid and solids 11.2.3 Composition of Organic Matter in Wastewater of the organic matter present in a wastewater, particularly its bio- of BNR processes. In the anaerobic zone,
chapter 12|11 pages
Aerobic Digestion
of aerobic bioreactors to stabilize par- of waste- of a relatively
chapter |27 pages
NAD process. It has also
of hydrolysis of particulate substrate under anoxic con- of this model also indicates that the overall stabilization of organic matter in the A/A D process will be the same as achieved in a CAD system
chapter 13|9 pages
Anaerobic Processes
The term anaerobic process refers to a diverse array of biological wastewater treat- ment systems from which dissolved oxygen and nitrate-N are excluded. In most instances they are operated to convert biodegradable organic matter, both soluble and particulate, to methane and carbon dioxide. Since methane is a sparingly soluble gas, most is evolved and recovered, thereby removing organic matter from the liquid
part |2 pages
Part IV
chapter 15|21 pages
Biofilm Modeling
of microorganisms. However, as discussed in Section 1.2.3, attached growth
chapter |6 pages
of Pseudoanalytical Approach. The pseudoanalytical approach al-
of the flux into a steady-state biofilm associated with a given ln(l + S[,)]} = st, + kl, are calculated with + 0.0017 + 0.0017)
chapter 16|15 pages
AEROBIC GROWTH OF BIOMASS IN PACKED TOWERS
Packed Towers of attached growth bioreactors were listed in Table 1.2. Among those,
chapter 17|2 pages
AEROBIC GROWTH OF HETEROTROPHS IN ROTATING Disc REACTORS
Rotating Disc of attached growth bioreactor is the rotating disc or touching the liquid surface in a long narrow tank. The shaft
chapter I|9 pages
(FL) I
· Ssb ) of substrate by the RDR and they must be solved simultaneously. For a given set of of the bioreactor. The only
chapter 18|5 pages
Fluidized Bed Biological Reactors
of fixed media bioreactors in which the media stays in one position of the hydraulic
chapter |2 pages
PartV
Applications: Attached Growth Reactors of ideal attached growth reactors and of a
chapter 19|49 pages
Trickling Filter
of attached growth biochemical opera- of the wastewater is accomplished by microorganisms growing attached of which there are several types. Trickling filters are aerobic and are
chapter |1 pages
If of
of a coupled TF/AS system. Unfortunately this cannot of substrate rather than on the growth of biomass. Thus, while of the suspended of heterotrophic biomass, cell debris, inert influent
chapter 20|25 pages
Rotating Biological Contactor
of aerobic attached of one to two revolutions per minute to alternately expose
chapter 21|24 pages
Submerged Attached Growth Bioreactors
of wastewaters of trickling filters and rotating biological of new
part |2 pages
Part VI
chapter 22|24 pages
Fate and Effects of Xenobiotic Organic Chemicals
of biogenic organic matter, nitrification, and deni- of biological phos-