Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey Planet Earth Abiotic component – non-living component Atmosphere (air) Lithosphere (soil) Hydrosphere (water) Biotic component – biosphere, living component Plants Animals Microorganisms Humans
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey Cell classification Acaryotic - viruses Prokaryotic – simple structure Eukaryotic – more complex structure Taxonomic classification Conventional classification – based on observable properties Kingdom phylum class order family genus species Genetic classification - phylogeny
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey Figure 4.1 Schematic of a rod-shaped bacterial (prokaryotic) cell.
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey Figure 4.2 Schematic of a eukaryotic cell.
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey Figure 4.3 Schematic of a virus.
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey Figure 4.4 Schematics of Anabaena and Chlorella algae.
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey Figure 4.5 Three bacterial cellular forms and arrangements.
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey Figure 4.6 Examples of a Diaptomus and Daphnia. Examples of Crustaceans/microcrustaceans
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey Figure 4.7 Photograph of Dr. W. Jack Lackey holding a rockfish (up to 200 cm long and 57 kg in weight).
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey Figure 4.8 Examples of fungi.
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey Figure 4.9 Examples of a leech and flatworm. Helminths - worms
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey Figure 4.10 Examples of macrophytes.
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey Figure 4.11 Example of a protozoan.
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey Figure 4.12 Example of a rotifer.
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey Figure 4.13 Diagram of a virus.
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey Figure 4.14 Bacterial growth curve.
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey Microbial Growth Specific growth rate, μ, changes as species of organisms change and as the environmental conditions change. A French microbiologist, Monod, developed a relationship that showed that the specific growth rate is a function of the maximum specific growth rate, μ max, and the amount of limiting substrate (food):
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey If we combine the two equations above we get an equation that describes microbial growth rate: When microbial growth takes place in a flow-through reactor we have to account for microorganism loss through death and decay (endogenous decay) which is represented in the equation below:
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey The net growth rate for a reactor is then obtained by adding equations 4.3 and 4.4: Or: Cell yield is defined as the quantity of biomass produced per unit of substrate (food) used:
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey The equation that describes the rate substrate is used, the specific substrate utilization rate, U, is: We can then define the yield as: The specific substrate utilization rate, U, can also be described using a Monod-type function: If we substitute equations 4.4 and 4.7 into equation 4.5, we get:
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey Figure 4.15 Representation of a food chain.
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey Figure 4.16 Simple food chain.
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey Figure 4.17 Example of a food web. Source:
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey Figure 4.18 Simplified diagram of the carbon cycle.
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey Figure 4.19 The nitrogen cycle in surface water. Source: EPA Nitrogen Control Manual (1993), p. 7.
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey Nitrification NH O 2 → NO H + + H 2 O NO O 2 → NO 3 - Overall NH O 2 → NO H + + H 2 O Nitrosomonas Nitrobacter Nitrifiers
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey Denitrification 6 NO CH 3 OH → 6 NO CO H 2 O 6 NO CH 3 OH → 3 N CO H 2 O + 6 OH - Overall 6 NO CH 3 OH → 3 N CO H 2 O + 6 OH -
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey Figure 4.20 The phosphorus cycle.
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey Figure 4.21 Schematic of simplified sulfur cycle.
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey Figure 4.22 DO profile for Norris Lake, September 5, Source:
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey Figure 4.23 Temperature profile for Norris Lake, September 5, Source:
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey Figure 4.24 Lake stratification during summer and winter.
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey Figure 4.25 Temperature and mixing profiles during turnover and stratification.
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey Dissolved Oxygen (DO) Depletion in Streams When a biodegradable organic is added to a natural water, bacteria naturally present in the water will begin to use the organic matter as a carbon/energy source. Aerobic organisms will use oxygen as the terminal electron acceptor in the process. This process is called deoxygenation. It can be modeled by the following equation: R deoxygenation = k D L Where: R deoxygenation = rate at which oxygen is removed from a stream, mg/L. d k D = deoxygenation rate coefficient (base e), d -1 L = ultimate biochemical oxygen demand (BOD), mg/L
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey At the same time deoxygenation is occurring oxygen may also be reintroduced into the system in a process called reaeration Reaeration takes place when oxygen from the atmosphere is dissolved into the water. When water is traveling quickly over rocks or through rapids oxygen is more quickly introduced into the water as opposed to a slow moving, quiet stream. The reaeration process can also be modeled by a first order process; R REAERATION = -k 2 D Where: R reaeration = rate of reaeration (rate at which oxygen is transferred into the stream) k 2 = reaeration rate coefficient (base e), d -1 D = dissolved oxygen deficit, mg/L D = DO sat - DO DO sat = DO saturation concentration at stream conditions DO = actual or measured DO
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey Figure 4.26 DO versus time.
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey DO Depletion Model (Streeter-Phelps Equation)
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey If we substitute Equation 4.30 into equation 4.29 we get: Now we integrate with the boundary conditions: When t = 0, D = D o, L = L 0, and When t=t, D = D t, L = L t
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey To use this equation we need to calculate the DO deficit at the point of dischagre, D o. First we must calculate the DO at the point of discharge: Now the DO deficit is: Sometimes we have to adjust the reaction rate constants for temperature. This can be done using the Van’t Hoff-Arrhenius equation:
Copyright ©2010 by Pearson Education, Inc. Upper Saddle River, New Jersey All rights reserved. Introduction to Environmental Engineering, First Edition Richard O. Mines and Laura W. Lackey Ө should be for k 2. For k D, Ө should be when the temperature is 20 0 C or less, and when the temperature is between 20 and 30 0 C. The maximum deficit will occur when the reaeration rate is equal to the deoxygenation rate. This point is called the critical pointand can be found be differentiating equation 4.33 and setting the result equal to zero: t c = time of travel to the critical point. Once you find t c, you can use that time in equation 4.33 to find the maximum deficit.