Lesson 6

Water purification (I)

1. Mind the pronunciation of the words below.

pharmacology ["fRmq'kOlqGI], ultraviolet ["Altrq'vaIqlqt], reverse [rI'vWs] osmosis [Pz'mqusIs], deionization [dJ"aIqnaI'zeISn], parasite ['pxrqsait], procedure [prq'sJGq], analysis [q'nxlqsIs], diarrhea ["daiq'rIq], hygiene ['haiGJn], technique [tek'nJk], protozoa ["prqutq'zquq], fungi ['fANgai; 'fANGai].

2. Remember the following words and word combinations.

purification – очистка

remove – удалять

raw water – необработанная вода

consumption – потребление, расход

application – применение

water softening – умягчение воды

suspended particles – взвешенные частицы

lead [led] – свинец

water treatment plant – водоочистная станция

copper - медь

determine = decide on – определять

access – доступ

lack – не иметь

through – 1) через, сквозь 2) путем, с помощью 3) благодаря

store – хранить

design – 1) проектировать 2) предназначать

save – 1) экономить 2) спасать 3) сберегать

3. Text.

Water purification is the process of removing contaminants and other harmful microorganisms from a raw water source. The goal is to produce water for a specific purpose with a treatment profile designed to limit the inclusion of specific materials; most water is purified for human consumption (drinking water). Water purification may also be designed for a variety of other purposes, including meeting the requirements of medical, pharmacological, chemical and other industries. Methods include, but are not limited to: ultraviolet light, filtration, water softening, reverse osmosis, ultrafiltration, deionization and powdered activated carbon treatment.

Water purification may remove: particulate sand; suspended particles of organic material; parasites, viruses; fungi; minerals such as calcium, silica, and magnesium; and toxic metals like lead, copper, and chromium.

Governments usually dictate the standards for drinking water quality. These standards will require minimum / maximum set points of specific contaminants. Quality standards in many countries require specific amounts of a disinfectant (such as chlorine) in the water after it leaves the water treatment plant to reduce the risk of re-contamination while the water is in the distribution system.

It is not possible to say whether water is safe for drinking just by looking at it. Simple procedures such as boiling or the use of a household activated carbon filter are not sufficient for treating all the possible contaminants that may be present in water from an unknown source. Even natural spring water - considered safe for all practical purposes some one hundred years ago - must now be tested before determining what kind of treatment, if any, is needed. Chemical analysis, while expensive, is the only way to obtain the information necessary for deciding on method of purification.

According to a 2007 World Health Organization report, 1.1 billion people lack access to an improved drinking water supply, 88% of the 4 billion annual cases of diarrhea disease are attributed to unsafe water and inadequate sanitation and hygiene, and 1.8 million people die from diarrhea diseases each year. The WHO estimates that 94% of these diarrhea cases are preventable through modifications to the environment and through access to safe water. Simple techniques for treating water at home, such as chlorination, filtering, and storing it in safe containers could save a huge number of lives each year.

Notes:

1. treatment profile – степень очистки

2. ultra filtration – ультрафильтрация (фильтрация коллоидных растворов)

3. particulate sand –мелкие частицы песка

4. World Health Organization (WHO) – Всемирная Организация Здравоохранения

5. set point – зд. заданное количество

6. fungi pl. of fungus – грибок (низший)

4. Find English equivalents of the following in the text.

удалять взвешенные частицы, токсичные металлы, максимальное заданное значение, дезинфицирующее средство, обратный осмос, активированный уголь, стандарты на качество питьевой воды, уменьшить риск, определить метод очиcтки, умереть от болезни, некачественная вода, путем улучшения окружающей среды, определенные материалы, повторное загрязнение, родниковая вода, не отвечающие требованиям, санитарно-гигиенические условия.

5. Give Russian equivalents.

water purification process, to remove toxic metals, the only way to obtain the information, to decide on method of purification, according to a report, access to a drinking water supply, household activated carbon filter, designed for a variety of other purposes, human consumption, simple technique, ultraviolet light, water softening.

6. Complete the sentences using the information from the text.

1) Drinking water is water purified for ….

a) a variety of purposes

b) human consumption

c) chemical and industrial applications

d) storing it in safe containers.

2) Certain amounts of chlorine is added to the water after it leaves the water treatment plant to ….

a) prevent diarrhea cases

b) meet the requirements of medical industry

c) improve sanitation and hygiene

d) to reduce the risk of re-contamination in the distribution system

3) Simple procedures to treat water at home include:

a) ultra filtration and deionization

b) ultraviolet light

c) boiling and filtering

d) water softening

4) Drinking water standards are set by ….

a) World Health Organization

b) public water supplies

c) governments

c) water treatment plants

5) The main cause of diarrhea is considered to be ….

a) the polluted environment

b) spring water

c) unsafe drinking water

d) the use of chlorine to treat water at home.

7. Translate the text in the written form (25 minutes).

Boiling. Historically, boiling is what has been used to disinfect water from microorganisms. In fact, when done correctly, it can kill most bacteria, but not all. Bacteria and protozoa are killed at the first bubble, and it takes about three minutes to kill the rest. The drawbacks to this method however are that first of all, it can require lots of fuel and cooking equipment. Secondly, water cannot be used immediately, as it needs cooling down. Thirdly, since it is so hot, some of the water may evaporate before its use. Fourth, the water can still contain harmful particles, so further filtering could be necessary. Finally, boiling water does not eliminate chemical pollutants (including chlorine), poor taste or foul odours, and in fact can leave a stale taste. Boiling water may be the only method when camping, but in a household, there are more effective and efficient methods available.

Дата добавления: 2015-07-14