Wastewater Systems: Chapter 3 Study Guide PDF

Process Systems Chapter 3: Wastewater Systems Reading Objectives: 1. Describe the purpose and fundamental concepts of wastewater systems. 2. Explain the purpose of the equipment components in a wastewater system, their operation/ control, and factors that affect their operation. 3. E...

Process Systems Chapter 3: Wastewater Systems Reading Objectives: 1. Describe the purpose and fundamental concepts of wastewater systems. 2. Explain the purpose of the equipment components in a wastewater system, their operation/ control, and factors that affect their operation. 3. Explain the process technician's responsibilities in operating wastewater systems. 4. List specific safety, health, and environmental concerns associated with wastewater systems. Reading Summary: I. Introduction a. Purpose and Fundamentals of Wastewater Systems i. Effluent -- finished stream from a treating process, especially from a wastewater treating facility ii. Purpose is to clean the water and make it safe before it is discharged iii. Method used to treat can vary depending on the influent source 1. May include screening, clarification, flocculation, coagulation, filtration, aeration, mixing, centrifugation, adsorption, gas transfer, evaporation, oxidation, neutralization, biological reactions and disinfection iv. Two major types 2. Storm water resulting from precipitation and is naturally occurring normally routed away from wastewater treatment plant a. Components of storm water must be analyzed before being rerouted include pH, total organic carbon (TOC) and oil and grease and if pollutants found it will be rerouted to a treatment facility b. Sanitary sewer facilities have kitchen and showers that will connect to the municipal sewer system 3. Process water is usually pretreated, tested and then sent back to the municipal water system II. Systems Components, Operating Principles, Controls, and Abnormal Conditions v. Lagoon system an artificial pool for storage and treatment of polluted or excessively hot sewage, industrial waste, etc. 4. Moves from one lagoon to another getting cleaner each time, there are microorganisms in these pools to eliminate hazards 5. Activated sludge process uses biology treatment method (bugs), excess microorganisms are removed 6. Preferred method because they are cost effective vi. Steps in treatment plants 7. Screening large coarse screen remove large objects 8. Settling suspended, lighter density sludge is allowed to separate from liquid, water insoluble contents will float to the top where it will be skimmed and discarded, heavier sludge will be collected at the base and discarded 9. Mix tank (premix tank) pH is adjusted and nutrients are added to promote healthy bacteria 10. Aeration basin air movers force large volumes of air to be pumped in, the aerobic action mixes water and exposes to air providing oxygen to bacteria that destroys waste c. Activated sludge is biologically active 11. Clarifier removes excess bacterial; a coagulant is added to clump into flocs later removed and recirculated 12. Release through filters of sand, gravel and coal the following items are also tested before release d. PH, chemical oxygen demand (COD), biological oxygen demand (BOD), total organic carbon (TOC), turbidity, specific chemicals such as copper, lead, phosphates, zinc, chromium, mercury, nickel and hydrocarbons b. System Instrumentation and Control vii. Flow, level and temperature are controlled viii. Contents stay below 104-degree Fahrenheit (40 C) c. Abnormal Conditions ix. Temperature must be regulated to ensure that the bacteria in the system is not harmed x. Rainstorms with higher-than-normal flow can overwhelm the system xi. Large leaks and spills from process plants are another abnormal condition that must be monitored because it can harm or kill bacteria xii. Chemicals used in the system are corrosive xiii. Testing and making sure the bacteria is growing and is healthy is important III. Process Technician's Responsibilities for Wastewater Systems d. Responsible to monitor to ensure that safeely and efficiently removeing pollutants e. Product is safe for environment f. Maintenance g. Require a water permit to operate IV. Safety, Health and Environmental Concerns h. Sudden increase of high organic carbon, temperature variations, or pH imbalances have potential to kill bacteria causing for discharge of untreated or undertreated effluent water i. Takes 4 weeks to regrow healthy bacteria j. Aeration is a drowning hazard k. Decomposition of organic material can create flammable gases such as methane or hydrogen sulfide Quiz **Question 1** The pH of alkaline substances (bases) is \_\_\_\_\_\_\_\_. above 7 under 5 under 7 above 15 **Feedback** Good work **Question 2** Which process technician duties are designed to ensure that the wastewater treatment plant produces a safe effluent stream that follows all regulations and permits? Analyzing samples, regulating flows, and making adjustments based on those test results Conducting regular audits of the wastewater treatment processes Supervising contractors hired to run the facility Working with the plant manager and meeting with government regulators **Feedback** Good work **Question 3** What is the term often used to describe the microorganisms that degrade organic contaminants from wastewater? Plankton Amoebae Nekton Bugs **Feedback** Good work **Question 4** What is another important process variable if biological treatment is involved in the wastewater treatment process? Flocculence Morbidity Temperature Turbidity **Feedback** That\'s not correct **Question 5** If sand filters begin to plug up, what should the process technician do? Reverse the flow to back flush the filter. Use a rake to remove the material clogging the filter. Add a solvent to unclog the filter. Replace the filter. **Feedback** Good work **Question 6** Which term refers to the measure of the quantity of hydrogen ions in a solution that can react and indicates whether a substance is an acid or a base? pH Chemical oxygen demand (COD) Acidity Total organic carbon (TOC) **Feedback** Good work **Question 7** The removal of toxic materials at an industrial plant before the wastewater is released to the municipal sewer is known as \_\_\_\_\_\_\_\_. pretreatment aeration filtration purification **Feedback** Good work **Question 8** What is the most common method of treating wastewater? An activated sludge process A lagoon system A chemical treatment system A distillation system **Feedback** That\'s not correct **Question 9** Influents are controlled by heat exchangers to stay below what temperature? 104 degrees Fahrenheit 108 degrees Fahrenheit 32 degrees Fahrenheit Room temperature **Feedback** Good work **Question 10** A substance with a pH of 9 is \_\_\_\_\_\_\_\_. a base an acid neutral acerbic **Feedback** Good work **Question 11** What must a wastewater facility have in order to operate? A four-star safety rating Articles of incorporation A plant charter A water permit **Feedback** Good work **Question 12** In wastewater treatment systems, which are the two important process variables? Flow and level Humidity and turbidity Acidity and toxicity Density and liquidity **Feedback** Good work **Question 13** What distinguishes a sanitary sewer from a storm sewer? The water in a sanitary sewer is a result of precipitation, whereas the water in a storm sewer originates in restrooms, sinks, or drinking fountains that dispose of waste or used water. The water in a storm sewer is much more turbulent than the water in a sanitary sewer. The water in a storm sewer is a result of precipitation, whereas the water in a sanitary sewer originates in restrooms, sinks, or drinking fountains that dispose of waste or used water. The water in a sanitary sewer has been thoroughly processed and purified whereas the water in a storm sewer originates in restrooms, sinks, or drinking fountains that dispose of waste or used water. **Feedback** Good work **Question 14** Why can spills to the process sewer cause safety, health, and environmental concerns? They may release toxic fumes into the environment. They may cause chemical burns to workers at the plant. They have the potential to kill the waste-consuming bacteria. They present a serious drowning hazard. **Feedback** Good work **Question 15** What is a total organic carbon (TOC) test? An analytical test that measures impurities due to carbon-based organic contamination A measure of the quantity of hydrogen ions in a solution that can react A measure of water pollution in which the sample is chemically oxidized A test in which oxygen is consumed by bacteria digesting a wastewater sample **Feedback** Good work **Question 16** The general term for an underground collection system for liquid waste material, rainwater, etc. is a \_\_\_\_\_\_\_\_. well lagoon sewer cistern **Feedback** Good work **Question 17** What is storm water? Rapidly flowing water resulting from a hurricane or other serious weather event Water that is suitable for drinking Any water released into a storm sewer Water that is a result of precipitation (rain, melting snow, sleet, and ice) **Feedback** Good work **Question 18** What term refers to the finished stream from a treating process, especially from a wastewater treating facility? Effluent Influent Discharge Expellant **Feedback** Good work **Question 19** What is a possible consequence of a pH imbalance in the process sewer? It might emit hazardous fumes. It might kill the waste-consuming bacteria. It might clog the outlets. It presents a serious drowning hazard. **Feedback** Good work **Question 20** What is chemical oxygen demand (COD)? A measure of water pollution in which a sample is chemically oxidized An analytical test that measures impurities due to carbon-based organic contamination A measure of the quantity of hydrogen ions in a solution that can react and indicates whether a substance is an acid or a base A measure of water pollution in which oxygen is consumed by bacteria digesting a sample **Feedback** That\'s not correct **Question 21** Why is the water in an aeration basin especially hazardous? Because aerated water is not like water in a pool and poses a drowning hazard Because of the potential for chemical burns Because of the presence of toxic fumes Because of the presence of poisonous snakes **Feedback** Good work **Question 22** What two flammable gases can be created when organic material decomposes during wastewater treatment? Hydrogen dioxide and carbon monoxide Hydrogen fluoride or hydrogen dioxide Hydrogen sulfide or methane Hydrogen chloride or carbon monoxide **Feedback** Good work **Question 23** In water treatment, what is a lagoon? An artificial pool for storage and treatment of polluted or excessively hot sewage, industrial waste, etc. A natural pond or lake converted for storage and treatment of polluted or excessively hot sewage, industrial waste, etc. An enormous tank used for storage and treatment of polluted or excessively hot sewage, industrial waste, etc. A natural inlet used for storage and treatment of polluted or excessively hot sewage, industrial waste, etc. **Feedback** Good work **Question 24** What does the term turbid mean? Unsanitary Cloudy Slow-moving Anaerobic **Feedback** Good work **Question 25** What is an effluent? The microorganisms added to degrade contaminants from wastewater The incoming stream to a treating process, especially to a wastewater treatment process The finished stream from a treating process, especially from a wastewater treatment process A chemical added to degrade organic from wastewater **Feedback** Good work