Главная страница Случайная страница
КАТЕГОРИИ:
АвтомобилиАстрономияБиологияГеографияДом и садДругие языкиДругоеИнформатикаИсторияКультураЛитератураЛогикаМатематикаМедицинаМеталлургияМеханикаОбразованиеОхрана трудаПедагогикаПолитикаПравоПсихологияРелигияРиторикаСоциологияСпортСтроительствоТехнологияТуризмФизикаФилософияФинансыХимияЧерчениеЭкологияЭкономикаЭлектроника
Solid biomass
|
|
Solid biomass is commonly used directly as a combustible fuel, in Biomass Fuelled Power Plants producing 10-20 MJ/kg of heat. Its forms and sources include wood fuel, the biogenic portion of municipal solid waste, or the unused portion of field crops. Field crops may or may not be grown intentionally as energy crop, and the remaining plant byproduct used as a fuel. Most types of biomass contain energy. Even cow manure still contains two-thirds of the original energy consumed by the cow. Energy harvesting via a bioreactor is a cost-effective solution to the waste disposal issues faced by the dairy farmer, and can produce enough biogas to run a farm.
With current technology, solid biomass doesn’t suit to be used as a transport fuel. Most vehicles require energy sources with high power density, such as that provided by internal combustion engines. These engines generally require clean burning fuel, which is generally in liquid form, and to a lesser extent, compressed gaseous phase. Liquids are more preferred because they can have a high energy density, and they can be pumped, which makes handling easier.
Non-transport applications can usually tolerate the low power-density of external combustion engines that can run directly on less-expensive solid biomass fuel, for combined heat and power. The first type of biomass is wood, which has been used for ages. Two billion people currently cook every day and heat their houses in winter burning biomass, which is a main contribution to man-made climate change global warming. The black soot carried from Asia to polar ice caps cause them to melt faster in summer. In the 19th century wood-fired steam engines were common, contributing significantly to industrial revolution of air pollution. Coal is a form of biomass that has been used for ages to produce non-renewable, highly-polluting fossil fuel.
Wood and its byproducts can now be converted by means of gasification into bio-fuel such as wood-gas, biogas, methanol or ethanol fuel; although further development may be required to make these methods affordable and practical. Sugar cane residue, wheat chaff, corn cobs and other plant matter can be burnt quite successfully.
Processes to harvest biomass from trees like poplars and willows and perennial grasses require less frequent cultivation and less nitrogen than do typical annual crops. Pelletizing miscanthus and burning it to generate electricity is being studied and may be economically viable.
Ex. 3 Answer the following questions:
1) In what way can biomass be used?
2) What kinds of biomass fuel do you know?
3) What is the original purpose of the diesel engine?
4) What is a major benefit of biodiesel usage?
5) What plants are grown specifically to produce ethanol?
6) Is solid biomass commonly used as a combustible fuel?
7) Why is liquid fuel more preferred than solid one?
8) Is coal a renewable low – polluting fossil fuel?
9) What trees require less frequent cultivation?
Ex. 4 True or false? If the sentence is false correct it.
1) Agriculturally produced biomass fuel can be burnt in internal combustion engines or boilers.
2) It’s impossible to use biodiesel in modern diesel vehicles without modifications in the engine.
3) Biodiesel can be made from waste and virgin vegetable and animal oils and fats.
4) The use of biodiesel increases emission of carbon monoxide and other pollutants.
5) Most vehicles require energy sources with high power density.
6) In the 19 th century, wood – fired steam engines were common, significantly contributing to industrial revolution of air pollution.
7) Processes to harvest biomass from trees like poplars, willows and perennial grasses require more frequent cultivation.
Ex. 5 Insert the omitted words: (consult the text).
1) Wood and its... can now be converted by means of …into woodgas, biogas, methanol or ethanol fuel.
2) Even cow... contains two – thirds of the original energy consumed by the cow.
3) Most vehicles require energy... with high power density.
4) One type of biomass is... which has been used for ages.
5) A major... of biodiesel usage is the... of CO2 emissions.
6) Another source of bio-fuel is sweet....
7) Plants use... to grow and produce biomass.
8) Biodiesel can be made from... and... vegetable and animal oils and fats.
(Benefit, photosynthesis, manure, sources, wood, waste, sorghum, byproducts, gasification, reduction, virgin).
Ex. 6 Find the English equivalents of the following words and word combinations:
| Биоматерия высвобождать тополь ива дизельное транспортное средство отработанные и чистые растительные и животные масла жидкое биотопливо многолетнее растение коровий навоз высокая энергетическая плотность | Willow high energy density cow manure waste and virgin vegetable and animal oils perennial grasses liquid bio-fuel biomatter poplar to release diesel vehicles |
Ex. 7 Find the Russian equivalents of the following words and word combinations:
| Сгораемое топливо менее дорогой Загрязнение воздуха сажа глобальное потепление ежегодный урожай кочерыжка кукурузного початка излучать сорго | Global warming sorghum corn cob to emit less expensive combustible fuel soot annual crop air pollution |
Ex.8 Make up 5 sentences of your own with words from ex-s 6, 7.
Ex.9 Make up sentences from two parts:
| Liquids are more preferred Two billion people cook every day and heat their houses in winter burning biomass In some areas corn, sugarbeets, sugar cane are grown specifically Bio-fuel is burnt The diesel engine was originally designed | to release its stored chemical energy. to produce ethanol. to run on vegetable oil rather than fossil fuel. because they have a high energy density. which is a major contribution to manmade climate change global warming. |
Ex.10 Put the verbs in Passive forms:
1) Sugar cane residue (to use) as bio-fuel.
2) Field crops (to grow) internationally as energy crop.
3) One type of biomass is wood which (to use) for ages.
4) Wood and its byproducts (to convert) into bio-fuel.
Ex. 11 Speak on the following topics:
1) The advantages of liquid fuel.
2) Kinds of bio-fuel.
3) The advantages of bio-fuel.
Ex.12 Retell the text.
Chapter 9
Ex. 1 Rambler the following words:
dryer –сушильный аппарат (сушилка)
pump – насос; работать насосом; накачивать, выкачивать
tank – цистерна, бак
drawback - недостаток
modulate – модулировать
hemisphere – полушарие
angle - угол
latitude - широта
batch – группа, комплект
to coat - покрывать
infra-red - инфракрасный
to average – в среднем равняться
circuit - цепь
fluid - жидкость
heat exchanger - теплообменник
solar heating system – солнечная система отопления
heat storage – тепловой аккумулятор/накопление теплоты
storage reservoir – водохранилище/резервуар для хранения
glycol - гликоль
thermal capacity - теплоёмкость
emissivity – коэффициент излучения
ambient – окружающая среда
glass plate – стеклянная пластина
to exploit - использовать
greenhouse effect – парниковый эффект
convection - конвенция
absorber - поглотитель
flow rate – расход/интенсивность подачи (кислорода)
heat transfer– теплопередача
absorbed heat – поглощённое тепло
to back up - поддерживать
to mount – устанавливать, монтировать
Ex.2 Read and translate the text: