This is the table of contents and a sample chapter from WSO Water Treatment, Grade 2, get your full copy from AWWA. awwa.org/wso © 2016 American Water Works Association Contents Chapter 1 Basic Microbiology and Chemistry 1 Chemical Formulas and Equations 1 Moles and Molarity 6 Equivalent Weights and Normality 7 Dilution Calculations 8 Standard Solutions 12 Chapter 2 Operator Math 15 Volume Measurements 15 Conversions 22 Average Daily Flow 30 Surface Overflow Rate 33 Weir Overflow Rate 36 Filter Loading Rate 38 Filter Backwash Rate 41 Mudball Calculation 43 Detention Time 44 Pressure 47 Flow Rate Problems 52 Chemical Dosage Problems 55 Chapter 3 USEPA Water Regulations 71 Types of Water Systems 71 Disinfection By- product and Microbial Regulations 72 Chapter 4 Coagulation and Flocculation Process Operation 89 Operation of the Processes 89 Dosage Control 93 Safety Precautions 93 Record Keeping 94 Chapter 5 Sedimentation and Clarifiers 97 Process Description 97 Sedimentation Facilities 98 Other Clarification Processes 104 Regulations 107 Operation of the Process 107 iii 000200010272023365_ch00_FM_pi-vi.indd 3 5/2/16 9:51 AM iv WSO Water Treatment Grade 2 Chapter 6 Filtration 115 Equipment Associated With Gravity Filters 115 Operation of Gravity Filters 123 Pressure Filtration 135 Regulations 138 Safety Precautions 138 Record Keeping 139 Chapter 7 Chlorine Disinfection 143 Gas Chlorination Facilities 143 Hypochlorination Facilities 155 Operation of the Chlorination Process 157 Chlorination Operating Problems 162 Safety Precautions 165 Record Keeping 170 Chapter 8 Iron and Manganese Treatment 173 Excessive Iron and Manganese 173 Control Processes 175 Control Facilities 178 Regulations 182 Manganese Greensand Filter Operation 182 Process Monitoring 188 Operating Problems 188 Record Keeping 188 Chapter 9 Fluoridation Process Operation 191 Operation of the Fluoridation Process 191 Fluoridation Operating Problems 193 Control Tests 194 Safety Precautions 195 Record Keeping 196 Chapter 10 Water Quality Testing 199 Testing and Laboratory Procedures 199 Physical and Aggregate Properties of Water 209 Chapter 11 Corrosion Control 221 Purposes of Corrosion and Scaling Control 221 Water System Corrosion 222 Scale Formation 226 Corrosion and Scaling Control Methods 227 Corrosion and Scaling Control Facilities 230 Chemical Feed Equipment 233 Chapter 12 Lime Softening 237 Lime Softening Chemical Reactions 237 Lime Softening Facilities 239 Regulations 244 000200010272023365_ch00_FM_pi-vi.indd 4 5/2/16 9:51 AM Contents v Chapter 13 Ion Exchange 247 Ion Exchange Softening 247 Facilities 247 Operation of Ion Exchange Processes 252 Operating Problems 254 Ion Exchange for Removal of Arsenic, Barium, Radium, Nitrate, TOC, and Uranium 255 Activated Alumina Fluoride Removal Process 257 Adsorptive Media 257 Chapter 14 Activated Carbon Adsorption 261 The Principle of Adsorption 261 Adsorption Facilities 262 Powdered Activated Carbon 263 Granular Activated Carbon 265 Regulations 268 Operating Procedures for Adsorption 268 Operating Problems 272 Control Tests 273 Record Keeping 276 Chapter 15 Aeration 279 Water-Into-Air Aerators 279 Air-Into-Water Aerators 284 Combination Aerators 285 Chapter 16 Membrane Treatment 291 Microfiltration Facilities 291 Pleated Membrane Facilities 294 Reverse Osmosis Facilities 297 Chapter 17 Plant Waste Treatment and Disposal 303 Removal of Sludge from Conventional Sedimentation Processes 303 Softening Sludge Handling, Dewatering, and Disposal 305 Solids Separation Technologies 306 Chapter 18 Instrumentation and Control Systems 313 Flow, Pressure, and Level Measurement 313 Other Operational Control Instruments 316 Automation 317 Computerization 318 Chapter 19 Centrifugal Pumps 321 Operation of Centrifugal Pumps 321 Centrifugal Pump Maintenance 325 Record Keeping 336 Pump Safety 336 000200010272023365_ch00_FM_pi-vi.indd 5 5/2/16 9:51 AM vi WSO Water Treatment Grade 2 Chapter 20 Treatment Plant Safety and Security Practices 339 Treatment Plant Safety Review 339 Plant Security 348 Chapter 21 Administration, Records, and Reporting Procedures 355 Process Records 355 Reporting 359 Plant Performance Reports 360 Public Relations 360 Chapter 22 Additional Level 2 Study Questions 363 Study Question Answers 369 Glossary 379 Index 387 000200010272023365_ch00_FM_pi-vi.indd 6 5/2/16 9:51 AM ChapterChapter 11 BasicBasic MicrobiologyMicrobiology andand ChemistryChemistry Chemical Formulas and Equations A group of chemically bonded atoms forms a particle called a molecule. The sim- plest molecules contain only one type of atom, such as when two atoms of oxygen combine (O2) or when two atoms of chlorine combine (Cl2). Molecules of com- pounds are made up of the atoms of at least two different elements; for example, one oxygen atom and two hydrogen atoms form a molecule of the compound water (H2O). “H2O” is called the chemical formula of water. The formula is a shorthand way of writing what elements are present in a molecule of a com- pound, and how many atoms of each element are present in each molecule. Reading Chemical Formulas The following are examples of chemical formulas and what they indicate. Example 1 The chemical formula for calcium carbonate is CaCO3 According to the formula, what is the chemical makeup of the compound? First, the letter symbols given in the formula indicate the three elements that make up the calcium carbonate compound: Ca = calcium C = carbon O = oxygen Second, the subscripts (the small numbers at the lower right corners of the letter symbols) in the formula indicate how many atoms of each element are present in a single molecule of the compound. There is no number just to the right of the Ca or C symbols; this indicates that only one atom of each chemical formula element is present in the molecule. The subscript 3 to the right of the O sym- Using the chemical bolizing oxygen indicates that there are three oxygen atoms in each molecule. symbols for each element, a shorthand CaCO3 way of writing what elements are present in a molecule and how many 1 atom 3 atoms atoms of each element are present in each of the 1 atom molecules. 1 000200010272023365_ch01_p001-014.indd 1 5/2/16 9:05 AM 2 WSO Water Treatment Grade 2 Determining Percent by Weight of Elements in a Compound If 100 lb of sodium chloride (NaCl) were separated into the elements that make up the compound, there would be 39.3 lb of pure sodium (Na) and 60.7 lb of pure chlorine (Cl). We say that sodium chloride is 39.3 percent sodium by weight and that it is 60.7 percent chlorine by weight. The percent by weight of each element in a compound can be calculated using the compound’s chemical formula and atomic weights from the periodic table. The first step in calculating percent by weight of an element in a compound is to determine the molecular weight (sometimes called formula weight) of the compound. The molecular weight of a compound is defined as the sum of the atomic weights of all the atoms in the compound. For example, to determine the molecular weight of sodium chloride, first count how many atoms of each element a single molecule contains: Na Cl 1 atom 1 atom Next, find the atomic weight of each atom, using the periodic table: atomic weight of Na = 22.99 atomic weight of Cl = 35.45 Finally, multiply each atomic weight by the number of atoms of that element in the molecule, and total the weights: Number of Atomic Total Atoms Weight Weight sodium (Na) 1 × 22.99 = 22.99 chlorine (Cl) 1 × 35.45 = 35.45 molecular weight of NaCl = 58.44 Once the molecular weight of a compound is determined, the percent by weight of each element in the compound can be found with the following formula: weight of element in compound percent element by weight = × 100 molecular weight of compound percent by weight Using the formula, first calculate the percent by weight of sodium in the The proportion, compound: calculated as a weight of Na in compound percentage, of each percent Na by weight = × 100 element in a compound. molecular weight of compound 22.99 molecular weight = × 100 The sum of the atomic 58.44 weights of all the atoms = 0.393 × 100 in the compound. Also called formula weight. = 39.3% sodium by weight 000200010272023365_ch01_p001-014.indd 2 5/2/16 9:05 AM Basic Microbiology and Chemistry 3 Then, calculate percent by weight of chlorine in the compound: weight of Cl in compound percent Cl by weight = × 100 molecular weight of compound 35.45 = × 100 58.44 = 0.607 × 100 = 60.7% chlorine by weight To check the calculations, add the percentages. The total should be 100: 39.3% Na + 60.7% Cl 100.0% NaCl Chemical Equations A chemical equation is a shorthand way, through the use of chemical formulas, to write the reaction that takes place when certain chemicals are brought together. As shown in the following example, the left side of the equation indicates the reactants, or chemicals that will be brought together; the arrow indicates which direction the reaction occurs; and the right side of the equation indicates the prod- ucts, or results, of the chemical reaction. calcium calcium react to calcium plus plus water bicarbonate hydroxide form carbonate chemical equation A shorthand way, using Ca(HCO ) + Ca(OH) 2CaCO + 2H O chemical formulas, of 3 2 2 3 2 writing the reaction that takes place when Reactants Products chemicals are brought together. The left side of the equation indicates The 2 in front of CaCO3 is called a coefficient. A coefficient indicates the relative number of molecules of the compound that are involved in the chemical the chemicals brought reaction. If no coefficient is shown, then only one molecule of the compound is together (the reactants); involved. For example, in the preceding equation, one molecule of calcium bi- the arrow indicates in which direction the carbonate reacts with one molecule of calcium hydroxide to form two molecules reaction occurs; and the of calcium carbonate and two molecules of water.