List several sources of the sludge production in the biological wastewater treatment. 4. Wastewater from the dairy industries contain dissolved sugars and proteins, fats, and possibly residues of additives, please describe a treatment technology for the dairy industry wastewater. 5. The pulp and paper mill is a major industrial sector utilizing a huge amount of lignocellulosic materials and water during the manufacturing process, and releases chlorinated lignosulphonic acids, chlorinated resin acids, chlorinated phenols, chlorinated hydrocarbons. Describe a wastewater treatment technology for the paper industry. 6. Please explain how oils and grease removal devices work. 7. What is the typical process used to treat industrial wastewater containing high concentration of organic material? Describe the process and explain why you choose the process. 8. Describe several technologies for sludge processing and disposal in biological wastewater treatment. 9. How disinfection with chlorine is carried out? Describe the equipment involved. 10. Explain the mechanisms in rapid filtration process.