The document describes the wastewater treatment process at a hospital. It consists of two phases. Phase 1 includes a primary sedimentation tank, aeration tank, and secondary sedimentation tank. Phase 2 includes screening, grit removal, aeration, and secondary sedimentation. Sludge is dried on beds and effluent is discharged to soak wells and a nearby lake. Proper wastewater treatment is important to remove hazardous materials from hospital wastewater before discharge to protect the environment and human health.

1. SDM COLLEGE OF ENGINEERING AND TECHNOLOGY,
DHARWAD-580002
(An Autonomous Institute under VTU Belgaum)
DEPARTMENT OF CIVIL ENGINEERING
TECHNICAL SEMINAR ON :
Waste water treatment in Hospitals
SUBMITTED BY
Samrudh P Shetty - 2SD20CV045
Under the Guidance of
Asst. Prof. Basavaraj G

2. CONTENTS
1. INTRODUCTION
2. WHY TREAT WASTEWATER
3. EFFECTS OF WATER POLLUTANTS
4. WASTEWATER TREATMENT FACILITY
5. CONCLUSION

3. INTRODUCTION
• Wastewater composition refers to the actual amounts of physical,chemical and biological constituents
present in wastewater.
• Hospital wastewater may contain various potential hazardous materials including, microbiological
pathogens, radioactive isotopes, disinfectants, drugs, chemical compounds and pharmaceuticals.
• The maior aim of wastewater treatment is to remove as much of the suspended solids as possible before
the remaining water, called effluent, is discharged back to the environment.
• The selection of suitable treatment technology and proper treatment of hospital wastewater is essential.

4. Why treat waste water ?
• Hospital wastewater consists of various potentially hazardous components that will cause many risks on
human and environment by polluting surface and ground water. Hence, hospital sewage treatment is very
much required.
• As solid material decays, it uses up oxygen, which is needed by the plants and animals living in the water.
• Fisheries -Clean water is critical to plants and animals that live in water.
• Wildlife Habitats-Our rivers and ocean waters teem with life that depends on shoreline, beaches and
marshes.

5. EFFECTS OF WATER POLLUTANTS
• If wastewater is not properly treated, then the environment and human health can be negatively impacted Decaying
organic matter and debris can use up the dissolved oxygen in a lake so fish and other aquatic biota cannot survive.
• Excessive nutrients, such as phosphorus and nitrogen (including ammonia), can cause over-fertilization of receiving
waters, which can be toxic to aquatic organisms, promote excessive plant growth, reduce available oxygen, alter
habitat and lead to a decline in certain species
• Bacteria, viruses and disease-causing pathogens can pollute beaches and contaminate shellfish populations, leading to
restrictions on human recreation, drinking water consumption and shellfish consumption other substances such as
some pharmaceutical and personal care products.
• Chlorine compounds and inorganic chloramines can be toxic to aquatic invertebrates ,algae and fish.

6. WASTEWATER TREATMENT FACILITY
This waste water from the main supply sewer is directly fed to the sewage treatment plant (SPT). The
feeding is done in two phases. The various components and the various operations that are carried out are
described as follows:-
MAIN SEWER
• A sewer is an underground conduit or drain through which sewage is carried
• For carrying the waste water in Hospitals, cement concrete main sewer has been provided.
• The main sewer carries wastewater from laboratories, toilets, kitchens, bathrooms, wastewater from other
domestic and medical activities.
• The water from the main sewer is then divided and distributed in two phases.

7. MAIN SEWER
PRIMARY SEDIMENTATION TANK CUM STORAGE TANK

8. • Phase 1 consists of a primary sedimentation cum storage tank, an aeration tank and secondary
sedimentation tank. The phase 2 consists of a screening chamber, a grit chamber, an aeration tank and a
secondary sedimentation tank. The description of these two phases has been provided as follows.
PHASE 1
PRIMARY SEDIMENTATION TANK CUM STORAGE TANK
• They are usually rectangular or circular
• Most sedimentation tanks are constructed with gently sloped bottoms
• The present sedimentation tank as is a rectangular type reinforced concrete primary sedimentation tank
• The tank is 13 m long , 2 m wide and 2.6 m deep
• The detention period corresponding to the tank is 2.5 hours
• The sludge moves to hoppers by gravity, where it is removed

9. AERATION TANK
• The water that overflows from the primary sedimentation tank is allowed to fall to the aeration tank
• Two mechanical horizontal axis type aerators are provided in the tank
• The water in the aeration tank is aerated for about 6 hours.
AERATION TANK

10. SECONDARY SEDIMENTATION TANK
• Activated sludge process is undergone in this tank as the efficient separation of the biological waste is
necessary.
• The secondary clarifier is a rectangular cement concrete structure with a length of 2.8 m breadth 2.4 m
and depth 3 m.
• The Phase 1 of the treatment plant has a capacity of processing 12 lakh liters of wastewater per day.
SECONDARY SEDIMENTATION TANK

11. PHASE II
• The part of wastewater that does not go into the phase 1 is treated in phase 2
SCREENING CHAMBER
• The main sewer feeds all the waste water to a rectangular conduit called screening chamber. Screening is
the first treatment station, both for surface and wastewater. Its purpose to:
• Protect the structure downstream against large objects which could create obstructions in some of the
facility's units, easily separate and remove large matter carried along by the raw water, which might
negatively affect the efficiency of later treatment procedures or make their implementation more difficult.
SCREENING CHAMBER

12. GRIT CHAMBER
• Sewage consists of a considerable amount of grit which consists of sand, gravel, silt, ash, cinders,
clinkers, egg shells etc.
• Grit removal is necessary to protect the moving mechanical equipment and pump elements from abrasion
and accompanying abnormal wear and tear, to reduce the formation of heavy deposits in pipes, channels
and conduits, and to reduce the frequency of the cleaning of sludge digesters.
GRIT CHAMBER

13. AERATION TANK
• After the grit chamber, the waste water is allowed to pass into an aeration tank
• The principle of working of this aeration tank is similar to that of phase 1
AERATION TANK

14. SECONDARY CLARIFIER TANK
• The secondary clarifier tank in phase 2 is similar in working and construction to that of phase 1. Only the
capacity is different
• The phase 2 of the treatment plant has a capacity of treating about 6 lac liters of wastewater per day
• The treated wastewater from the two phases is then separately taken to the sludge beds and from sludge
beds to the soak wells
SLUDGE BEDS
• The sludge in both the phases is applied on the sludge drying beds.
• The purpose of the sludge drying beds is to dewater the sludge
• There are 7 no. of beds provided at the present site and each bed has the dimensions of 4.5mx6m

15. • These beds consist of a 30 cm thick layer of sand and gravel on specially prepared open beds. The sludge
is applied on this layer and is allowed to dry.
• All the drainage from the beds/drains is collected in a pipe and returned to the secondary clarifier tank of
the phase 2 and again processed as discussed above, and the cycle continues
• Pick-up trucks are used for hauling the sludge cakes.
SLUDGE BEDS

16. SOAK WELLS
• The effluents from the secondary clarifier tanks in phases 1 and 2 are allowed to enter the soak wells
• Only a little amount of effluent is absorbed in the soak pits and a major portion remains unabsorbed.
• The unabsorbed wastewater effluent is collected and discharged directly into the adjacent Lake
SOAK WELLS

17. CONCLUSION
• The hospital effluents comprise of an array of toxic environmental contaminants. The intricate nature and
smaller biodegradability index of hospital effluents make their disposal a very difficult task.
• Bibliometric analysis revealed a drastic shift in the focus of researchers towards hospital waste
management resulting in enhanced productivity of the authors in recent times. Due to the extremely
hazardous and toxic nature of pollutants present in HWW, adequate treatment technologies and

18. THANK YOU