Task 4. Explain the italicized words from the text in a different way.

Task 5. Single out the main idea of the text and make a message on the given theme.

 

 

Практическое занятие 8. Очистка сточных вод

Task 1. Read and translate the following text.

SEWAGE TREATMENT

 

Sewage treatment is the process of removing contaminants from waste water, primarily from household sewage. Physical, chemical, and biological processes are used to remove contaminants and produce treated wastewater (or treated effluent) that is safer for the environment. A by-product of sewage treatment is usually a semi-solid waste or slurry, called sewage sludge. The sludge has to undergo further treatment before being suitable for disposal or application to land.

Sewage treatment may also be referred to as wastewater treatment. However, the latter is a broader term which can also refer to industrial wastewater. For most cities, the sewer system will also carry a proportion of industrial effluent to the sewage treatment plant which has usually received pre-treatment at the factories themselves to reduce the pollutant load. If the sewer system is a combined sewer then it will also carry urban runoff (stormwater) to the sewage treatment plant. Sewage water can travel towards treatment plants via piping and in a flow aided by gravity and pumps. The first part of filtration of sewage typically includes a bar screen to filter solids and large objects which are then collected in dumpsters and disposed of in landfills. Fat and grease is also removed before the primary treatment of sewage.

Sewage may include stormwater runoff or urban runoff. Sewerage systems capable of handling storm water are known as combined sewer systems. Combined sewers require much larger and more expensive treatment facilities than sanitary sewers. Heavy volumes of storm runoff may overwhelm the sewage treatment system, causing a spill or overflow. Sanitary sewers are typically much smaller than combined sewers, and they are not designed to transport stormwater. Backups of raw sewage can occur if excessive infiltration/inflow is allowed into a sanitary sewer system.

As rainfall travels over roofs and the ground, it may pick up various contaminants including soil particles and other sediment, heavy metals, organic compounds, animal waste, and oil and grease. Some jurisdictions require stormwater to receive some level of treatment before being discharged directly into waterways. Examples of treatment processes used for stormwater include retention basins, wetlands, buried vaults with various kinds of media filters, and vortex separators. Industrial wastewater may contain pollutants which cannot be removed by conventional sewage treatment.

Task 2. Translate the following words from the text:

процесс удаления загрязнителей из сточных вод; побочный результат; жидкая глина; промышленные сточные воды; городская сточная вода; мусорный контейнер; система очистки канализационной воды; санитарные канализационные трубы; затоплять; засорение стока; водоспуск; заболоченные земли; погребные своды.

 

Task 3. Make up 15 questions to the text.

Task 4. Single out the main idea of the text and make a message on the given theme.

Практическое занятие 9. Этапы очистки сточных вод

Task 1. Read and translate the following text.

STAGES OF SEWAGE TREATMENT

 

Sewage collection and treatment is typically subject to local, state and federal regulations and standards. Sewage treatment generally involves three stages, called primary, secondary and tertiary treatment.

Primary treatment consists of temporarily holding the sewage in a quiescent basin where heavy solids can settle to the bottom while oil, grease and lighter solids float to the surface. The settled and floating materials are removed and the remaining liquid may be discharged or subjected to secondary treatment. Some sewage treatment plants that are connected to a combined sewer system have a bypass arrangement after the primary treatment unit. This means that during very heavy rainfall events, the secondary and tertiary treatment systems can be bypassed to protect them from hydraulic overloading, and the mixture of sewage and stormwater only receives primary treatment.

Secondary treatment removes dissolved and suspended biological matter. Secondary treatment is typically performed by indigenous, water-borne micro-organisms in a managed habitat. Secondary treatment may require a separation process to remove the micro-organisms from the treated water prior to discharge or tertiary treatment.

Tertiary treatment is sometimes defined as anything more than primary and secondary treatment in order to allow ejection into a highly sensitive or fragile ecosystem. Treated water is sometimes disinfected chemically or physically prior to discharge into a stream, river, bay, lagoon or wetland, or it can be used for the irrigation of a golf course, green way or park. If it is sufficiently clean, it can also be used for groundwater recharge or agricultural purposes.

Task 2. Translate the following words from the text:

  releasing untreated wastewater; federal regulations and standards; temporarily holding the sewage; quiescent basins; heavy solids; settled and floating materials; secondary treatment; bypass arrangement; the primary treatment unit; tertiary treatment systems; hydraulic overloading; suspended biological matter; separation process; ejection; disinfected chemically or physically.