Disposal by Sanitary Landfill

8/12/2019 Disposal by Sanitary Landfill

1/35

OBJECTIVES :

Understand what sanitary landfill is Understand its factors that needs

consideration upon application of sanitary landfill

Recognize the equipments used in sanitary

landfill


2/35

-defined as a land disposal site

employing an engineered method of

disposing of solid wastes on land in amanner that minimizes environmentalhazards by spreading the solid wastesto the smallest practical volume, and

applying and compacting covermaterial at the end of each day.

What is a sanitary landf i l l?


3/35

SANI TARY LANDF I LL

Controlled method of refuse disposal.Environmental and safety aspects areconsidered during the process

Refuse is dumped in accordance with apreconceived plan, compacted, andcovered during and at the end of eachday

Creating a landfill includes planning,design, implementation, operation,monitoring and controlled abandonment


4/35

SANITARY LANDFILLS


5/35

FACTORS TO CONSIDER IN SANITARY

LANDFILL :

LEGAL REQUIREMENTS

INTERMUNICIPAL COOPERATION

SOCIAL AND POLITICAL FACTORS

PLANNING


6/35

6

SITE SELECTION

Natural environment Ecology

Landscape

Water protection

General plans of the region Structure of the settlements

Distance to the sources

Access of roads, public utilities, etc.

Ownership of the area, present landuse

Types and quantity of the wastesurfacearea available


7/357

SITE SELECTION

Topography Climate

Prevailing wind

Hydrogeology, geology, earth movement Classification of the area (depends on the

soil characteristics and the type of waste)

Politics

Public acceptance


8/358

OPTIMAL SITE

IN THE DESERTLITTLE PRECIPITATION

HIGH EVAPOTRANSPIRATIONNO LEAKAGE

THICK UNSATURATED ZONE

NO NEIGHBOURS

FLAT AREA

LITTLE POTENTIAL OF GROUNDWATER FLOW

LEAKAGE STAYS IN THE AREA


9/359

FAVOURABLE SITES

clay

clay

Organic material

(peat bog)

Hard crystalline

rocks (few

fractures)

sand

silt Unsaturated

zone


10/3510

UNFAVOURABLE SITES

sand

limestone

shal

e

Sand and

gravel

High groundwaterlevel

no leakage water

Penetrates to the limestone

leakage 2 km further


11/3511

STAGES OF LANDFILLS

1. INITIAL STAGE

1. A

Initial stagewe put the waste to the site

1. B

Transition stagewhen the leakage is produced

2. ACID STAGE

Bacteria create complex organic acidspH decrease

Heavy metals become soluble

Increase of heavy metal content in the leakage

1-5 years


12/3512

STAGES OF LANDFILLS

3. METHANIGENIC STAGE

Bacteria produce methane gas + CO2+ H2O

They use organic acid

Increase of pH

Decrease of heavy metal content in the leakage

Can take 50100 years (we do not know)

4. FINAL STAGE

Bacteria which need the organic acid die

Oxygen comes inOrganic matter has been transformed (80%)

Raise of the redox-potential

Decrease of pH

Increase of heavy metals in the leakage


13/3513

PARTS OF A SANITARY LANDFILL

Disposal site provided with appropriate protection

Drainage system for the leachate Storage basin for leachate water

Treatment facility for leachate water

Buildingsoffice, storage facility, restrooms, garage

Fence around the disposal site

Weigh station

Registration system

Compacting machines, other vehicles

Public utilitiesdrinking water, sewerage, electricity,

telephone Washing facilities for containers, vehicles

Roads

Sorting facility

Monitoring system


14/35

Wh l dfill i f ll l f


15/35

Electricity generator

building

Methane storage

and compressorbuilding

Pipes collect explosive

methane for use as fuel

to generate electricity

Methane gasrecovery well

Compacted

solid waste

Groundwater

When landfill is full, layers of

soil and clay seal in trashTopsoil

Sand

Clay

Garbage

Probes to detect

methane leaks

Leachate

treatment system

Leachate

storagetank

Leachatepipes

Leachate pumpedup to storage tankfor safe disposal

Leachate

monitoring

well

Groundwatermonitoring

well

Clay and plastic lining to

prevent leaks; pipes collect

leachate from bottom oflandfill

Garbage

Sand

Syntheticliner

Sand

Clay

SubsoilFig. 13-18, p. 293

Stepped Art


16/35Fig. 13-19, p. 293


17/3517

EQUIPMENTS USED IN

SANITARY LANDFILL


18/35

SCRAPPER


19/35

CRAWLER TRACTOR


20/35

DRAG LINE


21/35

FRONT-END

LOADER


22/35

MOTOR

GRADER


23/35

23

EFFECTS OF LANDFILLS

Operating landfill Noise

Gas to the atmosphere, ground

Leachate (ground water pollution)

Wind blown litter and dust

Birds, insects

Surface runoff (pollution of surface waters)

Completed landfill

Gas to air, ground

Contaminated crops

leachate


24/35

INCINERATION


25/35

INCINERATION

A waste treatment process that involves the combustion oforganic substances contained in waste materials.[1]

Incineration and other high-temperature waste treatment

systems are described as "thermal treatment". Incineration

of waste materials converts the waste into ash, flue gas,and heat. The ash is mostly formed by the inorganic

constituents of the waste, and may take the form of solid

lumps or particulates carried by the flue gas. The flue

gases must be cleaned of gaseous and particulate

pollutants before they are dispersed into the atmosphere.

In some cases, the heat generated by incineration can be

used to generate electric power.


26/35


27/35


28/35

Classifications of Incinerators

Grate

Open rack

Stationary or moving

Air circulation Large and irregular

wastes

Hearth

Solid plate

Variety of waste

Suspension

Sand or alumina bed

fluidized with air

Relatively uniformfeed size


29/35

Typical Process Flow Diagram

Waste

Storage

Pre-processing/blending

Incineration Flue Gas

Pollution

Control

Ash Stabilization

Landfill

Effluent

POTW


30/35


31/35

Environmental

Considerations

Tonne of waste creates 3.5 MW of energy(eq. to 300 kg of fuel oil) powers 70homes

Biogenic portion of waste is consideredCO2neutral (tree uses more CO2duringits lifecycle than released during

combustion) Should not displace recycling


32/35

Waste Incineration -

Disadvantages High capital cost

Skilled operators are required (particularly for boiler

operations)

Some materials are noncombustible

Some material require supplemental fuel

Public disapproval

Risk imposed rather than voluntary

Incineration will decrease property value (perceived not

necessarily true)

Distrust of government/industry ability to regulate


33/35

Flue Gas Pollutants

Particulates

Acid Gases

NOx

CO

Organic Hazardous Air Pollutants

Metal Hazardous Air Pollutants


34/35

Questions?


35/35

Trade-Offs: Incineration

Documents

Disposal by Sanitary Landfill