Group 14 - Pit Latrine

7/23/2019 Group 14 - Pit Latrine

http://slidepdf.com/reader/full/group-14-pit-latrine 1/19

PIT LATRINES

Group 14

CE10B038 Morla Meenakshi

CE10B089 Kancharla PradeepCE10B091 Manish Kumar Shakya

CE10B092 Midhun Babu P

CE10B093 Myneni Venu Gopal

CE09B008 Bhupathi Swetha



INTRODUCTION

On site waste water treatment system

Cheapest and the Most Basic

form of Improved Sanitation

Consists of

a. Dug pit

b. Cover slab/floor

c. Superstructure

Usual depth > 2m

Soil Cover depth> 0.5m

Design storage capacity: at least 1yr ofsludge production.



Site selection and construction



Contd..

Rocky ground layer is avoided.

If the soil is loose the pit needs to be lined with,

for example, loose bricks to prevent the wall from

collapsing.

Ground water level should not be shallow.



MECHANISM Collects excreta in the pit dug below.

Natural Bacteria in the Faecal sludge degrade the volume of COD over time

into:

Natural Gases-

1. escapes via hole in the seat or

2. Diffuse into ground water

• Water -seeps through ground

• Degradation:

1. Top layer- aerobic processes

2. Bottom layer-anaerobic process-releases CO2, methane, sulphuric gases

decomposition of organic matter by soil bacteria



Contd..



Contd..



Pretreatment and Posttreatment ?

Since the degradation of waste by bacteria is the

only process, there will not be any pre treatment

and post treatment.



Types of pit latrine

Pit latrine with a slab

Ventilated improved pit latrine

Ecological sanitation



PIT LATRINE WITH SLAB• A normal pit latrine with a slab

ADVANTAGES:

• Low construction cost using local material and local skills

• Avoid contamination of surface water and top soil if properly installed andmaintained.

• They do not require water so are appropriate in areas where there is noadequate water supply.

DISADVANTAGES:

• Foul odour

• Favourable place for the breeding of flies and mosquitoes.

• susceptible to failure/overflowing during floods

Seepage of water into the surrounding soil through the sides and bottomof the pit causing

1. die-off of bacteria and viruses during storage and as the water percolatesthrough the soil

2. pollution of groundwater may occur.

Some of the chemicals like nitrates cannot be removed by bacteria

Emptying requires mechanical suction of the sludge.



VENTILATED IMPROVED PIT

• Improvement over the

simple dry pit latrine.

• vent pipe installed into the pit

• Painted black to absorb sun-light.

• Exhausts the foul odour from

the pit and control flies

•

Interior should be dark-to avoid flies



Ecological sanitation

• Principle : To make use of excreta by transformingit into a soil improver and fertiliser for agriculture.

• To decrease contamination of the environment

caused by human excretion and to prevent faeco-orally transmitted diseases.

• Amount of artificial fertiliser used in cultivation offields is decreased.



Types

• Arborloo – a single pit method

•



Fossa Alterna – a double pit method



Bio-Effector - a natural bioremediation product

that rapidly promotes microbial activity in

anaerobic and aerobic environments.



Recurrent expenditure benchmarks for basic

sanitation services

Break down ofreccurent

expenditures

Traditional Pit VIP Pit

Operational andminor expenditure 0.5-1$ 1-4$

Capitalmaintenanceexpenditure

0.5-1.5$ 1-1.3$

Expenditure on

direct support

0.5-1.5$ 0.5-1.5$

total 1.5-4$ 2.5-8.5$



Rating:Parameter Weight(W) Grade(G) W*G

Costrequirement

3 9 27

Time consumedFor reduction ofCOD

4 7 28

Energy requiredfor operation

3 10 30

Degradationlevel

4 7 28

Hygiene 4 6 24

Areaconsumption

3 8 24

Resourcesusage(eg:water)

2 9 18

AVERAGE 7.78



Citations:http://labspace.open.ac.uk/

http://www.susana.org/

http://en.wikipedia.org/wiki/Pit_toilet https://www.engineeringforchange.org/solution/library/.../S00

040

http://www.unep.or.jp/ietc/publications/freshwater/sb_summ

ary/5.asp

http://labspace.open.ac.uk/


http://en.wikipedia.org/wiki/Pit_toilet

https://www.engineeringforchange.org/solution/library/.../S00040


http://www.unep.or.jp/ietc/publications/freshwater/sb_summary/5.asp






http://en.wikipedia.org/wiki/Pit_toilet


http://labspace.open.ac.uk/



THANK YOU!!

Documents

Group 14 - Pit Latrine