fis_ling_energy ppt

8/14/2019 Fis_Ling_Energy Ppt

1/26

Energy

Fisika lingkungan S1 PFis

Pertemuan 2Leo Sutrisno


2/26

Bio-energy

Bio-energy is produced by the release of stored chemicalenergy contained in fuels made from biomass.

Biomass is actually a product of solar energy that has beenstored by the photosynthetic activity of plants.

The plants remove CO2 from the atmosphere and combine it

with water to produce biomass. Biomass is in many common waste products, such as:

agricultural waste

forest waste

municipal waste

food processing waste

Bio-energy is not a new concept. It is one of the oldest of allenergy resources, beginning with the controlled use of fire toprovide heat, light and cooking for earliest mankind


3/26

Benefits of Bio-energy

Biomass can be used as a source of energy indefinitely. Due to the short replication cycle of biomass, using bio-energy

does not increase atmospheric carbon dioxide. Bio-energy has a generally positive impact on the local

economy.

More local jobs are created and material requirements areincreased The use of biomass provides significant benefits to other local

industries. For example, the removal of dead, diseased or low-quality trees from forests for fuel prepares the area forreplanting more valuable tree species.

Biomass materials are often waste products from existingindustrial activities that would otherwise be disposed of--atconsiderable cost.

By growing biomass for use as a source of energy, you canimprove the environment.


4/26

Landfill Gas

All landfills generate a by-product known as landfill gas. Landfill gas contains approximately 50 percent methane, which makes it an

excellent source of energy. On the down side, methane has a globalwarming potential of 21 relative to CO2. In other words, one tonne ofmethane produces the same greenhouse gas (GHG) effect as 21 tonnes ofCO2. Capturing and converting LFG into energy prevents it from escapinginto the atmosphere.

There are two ways to manage LFG. It can be either flared (combustedunder controlled conditions) or used as an energy source. When LFG isflared, the methane is converted into CO2. This reduces GHG emissions,eliminates odour problems and destroys contaminants. When LFG is usedfor energy, it conserves non-renewable sources of energy, such as fossilfuels. Either way, capturing and using LFG has a positive effect on climatechange.

Two common uses for LFG are electricity generation produced by runningengines or steam turbines and combustion as an alternative fuel.

Landfill gas is a harmful GHG when released into the atmosphere.Collecting and combusting it, however, prevents a number of adverseeffects, such as gas migration, foul odours and the potential for explosion. Italso reduces the factors contributing to climate change and offsets the useof non-renewable sources of fuel.


5/26


6/26

Biogas

certain strains of bacteria produce a combustible gas when they digestbiomass in the absence of oxygen. This process is called anaerobic

digestion Using a biological treatment process called anaerobic digestion can produce

biogas as a by-product. Biogas typically contains between 60 and 70 percentmethane.

Anaerobic treatment has been historically used to biologically stabilize high-strength wastes at a low cost.

Anaerobic digestion is a process that occurs in nature.

Anaerobic digestion involves bacteria that require an environment that is voidof oxygen to survive. Converting organic waste to methane gas by anaerobicdigestion can be considered a two-step process. The first step involves a group of anaerobic bacteria referred to as the

acid formers that produces organic acids as a by-product of the initialorganic degradation.

The second step involves a group of bacteria known as the methane

formers that breaks down the organic acids and produces methane as aby-product of the degradation of the organic acids. The research has produced a number of patented systems that provide a

variety of advantages in terms of system efficiency, size, capital cost, treatmentflexibility, process stability and operating costs.


7/26

BIOGAS : Gas yang dilepaskan jika bahan organik seperti kotoran hewan

atau manusia direndam air dalam wadah tertutup/ anaerobik (BSTID, 1977)

Terjadi tiga tahap reaksi akibat aktivitas mikroorganisme anaerobik

Terdiri dari CH4, sedikit CO2 dan H2S


8/26

Skema Produksi Biogas dalam Sistem Pertanian

Terpadu


9/26

Powering vehicles with ethanol

Ethanol is produced from thestarch, or cellulose andhemicellulose components ofbiomass.

Ethanol can be blended with

gasoline to produce anenvironmentally beneficialtransportation fuel. The mostcommon blend, which iscomposed of 10% ethanol and90% gasoline, is known as

E10. It can be burned in anycar.


10/26

Making solid fuels more efficient

Some solid biomass is difficult to handle and doesntburn efficiently. To make this biomass easier tohandle and burn, many processes have beendeveloped. Some of these processes include: size reduction by chopping and grinding

screening to provide a more uniform particle size

mechanical and thermal drying to reduce moisturecontent

classification/cleaning for removal of unwantedcontaminants such as soil, rocks and scrap metal


11/26

Combustion to heat homes

The combustion of biomass,

particularly firewood, is a

long-standing tradition in

many of the rural areas of

Canada. Chunkwood that is

split and dried is burned in

high-efficiency enclosed

fireplaces, box-stoves,

furnaces, and cook-stoves.

Many cook-stoves and

furnaces are fitted with aheating coil to provide

domestic hot water and

space heating.


12/26

Bio - diesel

Vegetable oils from canola seeds, corn

seeds, sunflower seeds, flax seeds etc.can be treated to create a clean-burningfuel known as biodiesel. The most directway to extract the oil from the seeds is touse mechanical or mechanical/solventextraction. Extensive road tests ofbiodiesel fuel in trucks have proved that it

is a suitable fuel, especially if petroleumbecomes excessively costly orunavailable.


13/26

Diagram proses

biodiesel


14/26


15/26

Bio-oil A liquid known as bio-oil can be created from biomass found in

forestry and agricultural residues. The biomass is thermochemically

converted to bio-oil by using processes called direct liquefaction orfast pyrolysis. Direct liquefaction is a slow process that is conducted at high

pressure and moderate temperature. It uses a catalyst and often anoxygen scavenger to create a heavy, thick bio-oil with a low watercontent and a low oxygen content.

The fast or flash pyrolysis processes for creating bio-oil apply rapidheat to small biomass particles to high temperatures in the absenceof added oxygen. This process breaks down the biomass structureinstantly to produce a high yield of condensable organic liquids. Theliquids are typically 65% liquid bio-oil, 15% solid char and 20%gases. The char and gases are often burned to dry and pyrolyse thebiomass.

However, bio-oils are low in viscosity and have been successfullyburned in boilers, kilns, turbines and diesel engines. In the future,bio-oil might be burned with a small diesel pilot fuel in large enginesfor electrical generation or in locomotives or ships.


16/26

Bio-oil


17/26


18/26

Earth and Geothermal Energy

There are two types of energy that can be

obtained from the earth:

earth energy

and geothermal energy.
http://www.canren.gc.ca/tech_appl/index.asp?CaId=3&PgId=8http://www.canren.gc.ca/tech_appl/index.asp?CaId=3&PgId=8http://www.canren.gc.ca/tech_appl/index.asp?CaId=3&PgId=8http://www.canren.gc.ca/tech_appl/index.asp?CaId=3&PgId=8


19/26

earth energy Earth energy uses temperatures found in the earth or below

water to cool or heat air and water for buildings. For example, aheat pump can extract heat from underneath the ground to heata building. In the summer, the pump can be reversed to provideair conditioning by moving hot air out of the building and downinto the ground t's more efficient to use earth energy than it isto use a combustion furnace. That's because it requires lessenergy to move heat from one place to another than it does to

convert one kind of energy into another, which is what afurnace does. Canada uses one-quarter of its total energyconsumption on space heating or cooling and water heating orcooling.

Earth energy systems can also reduce the

emission of greenhouse gases.
http://www.canren.gc.ca/tech_appl/index.asp?CaId=3&PgId=8http://www.canren.gc.ca/tech_appl/index.asp?CaId=3&PgID=339http://www.canren.gc.ca/tech_appl/index.asp?CaId=3&PgID=339http://www.canren.gc.ca/tech_appl/index.asp?CaId=3&PgId=8


20/26


21/26


22/26


23/26

Geothermal Energy

Geothermal energy uses steam or hot water in the earth's crust topower turbines or to heat buildings or water. The earth's crust

contains a large amount of energy. The lava that flows from avolcano is a vivid example of the energy in the earth's crust. If thelocal geography has the right features, geothermal facilities can beinstalled. The facilities capture steam as it escapes from cracks orholes in underground rocks. Geothermal energy requires a sourcetemperature of more than 100C to drive a generating turbine.

Hot water from within the earth can heat buildings with noconversion. The famous hot springs in Banff, Alberta are anexample of geothermal direct heat at a resort.

Geothermal energy is used widely in the Philippines, Italy,Indonesia, Mexico, New Zealand, Japan and China. Iceland relieson geysers as its principal source of heat. Several northerncommunities around the world circulate this type of heated waterthrough pipes under roads to melt ice from the pavement, and thewater is also used in aquaculture, car washes and similarapplications.

In Canada, there is a test geothermal site in the Meager Mountain -Pebble Creek area of British Columbia. A 100 MW electrical facilitymight be developed at that site after further testing.


24/26

Benefits of Earth and Geothermal Energy

The operating costs of earth energy systems are much lower than the cost tooperate a combustion furnace with an air conditioning unit. On average, anearth energy system can save two-thirds of the cost to heat and cool withelectricity.

Earth energy can provide heating in winter, cooling in summer, and year-round hot water for home use.

An earth energy system can reduce greenhouse gas emissions by more thantwo-thirds compared to similar systems that use carbon-based fuel.

Earth energy systems provide constant low-level heat, which eliminates the

need to change thermostats at night. Earth energy systems do not produce the odour that is found in natural gas,

oil or propane furnaces. Earth energy systems are located inside a building, which eliminates the

adverse effects of nature and any accidents or vandalism, thereby increasingthe system's life and efficiency. Penetrations through the building's walls orroof increase energy performance and reduce the risk of structural damage.

Because there is no combustion, earth energy systems cannot explode andthere is no need to store fuel.

In many cases, the cost savings from reduced overhead space in the ceilingand the mechanical room can offset any increased cost for the installation ofthe system.


25/26


26/26

fis_ling_energy ppt

Documents