STP

IDENTIFICATION OF STP
S.NO	Name	Description	Particular
	Sewage Treatment Systems	Sewage treatment is the process of removing	The microbial population in treatment process can be
		contaminants  from waste water,  primarily  from	cultured using the following systems:
		household sewage. It includes physical, chemical and	a) Suspended growth system — In this system,
		biological processes to remove these contaminants and	microorganisms remain in suspension and
		produce environmentally safe treated waste water	their concentration is related to mixed liquor
		(or treated effluent).	suspended solids (MLSS).
		The  by-product  of  sewage  treatment  is  usually  a	b) Attached growth system — In this system,
		semisolid waste or slurry, called sewage sludge, that	microorganisms are developed over mobile or
		has to undergo further treatment before being suitable	immobile solid covered in biomass (slime).
		for disposal or further application .	c) Combined growth system — In this system,
		The main objective of treating waste water is to	both systems are used to attain the shock
		stabilize decomposable organic matter present in the	loads.
		sewage so as to produce treated effluent and sludge,
		which can be disposed of in the environment without
		causing health hazards or nuisance.
	Technologies	a) Extended  aeration with  activated  sludge
		process (EAASP) — Activated sludge process
		is  the  biological  process  by which  non-
		settleable substances occurring in dissolved
		and  colloidal  forms  are  converted  into
		settleable sludge which is removed from the
		liquid carrier (water).
		This process is well suitable for completely
		populated community and does not require
		skilled labour for handling the plant. It is time
		tested and requires more number of units to
		achieve biological oxygen demand (BOD) less
		than 10 ppm, like coagulants required for
		better quality.
		b) Sequential batch reactor (SBR) — It is an
		activated sludge process designed to operate
		under non-steady state conditions. An SBR
		operates in a true batch mode with aeration
		and sludge settlement both occurring in the
		same tank. There is a degree of flexibility
		associated with working in a time rather than
		in a space sequence.
		Plant for this process requires less space due
		to batch process, well suitable for modular
		growth. It can handle smallest flows and the
		desired  quality  can  be  achieved without
		coagulants.  It  requires  good  quality  of
		decanters, and skilled labour as the process is	Pollutants in sewage
		timer-based automation.
			• BOD(Bio Chemical Oxygen demand)
		c) Membrane  bio-reactor  (MBR) —  It  is  a	•COD(Chemical Oxygen demand)
		continuous  process  of  activated  sludge	•TSS(Total Suspended Solids)
		treatment,  but  solids  separation  is  done	PH
		through pressurised system or through media.
		As  there  is  physical  barrier  for  solid	BOD(Biochemical Oxygen demand)
		separation, quality of treatment is good.
		It is suitable for any type of growth pattern	The BOD is an important measure of water quality .It is measure of the amount of oxygen needed by bacteria and other organisms to oxidize the organic matter present in a water sample over a period of 5 days at 20 degree C.
		and can handle smaller flows. It requires less
		space, and skilled labours to handle.	COD (Chemical Oxygen Demand)
		d) Rotating bio-bed reactor (RBBR) — It is
		combined  growth  process.  Bacteria  are	Ø COD Measures all organic carbon with the exception of some aeromatics (BENZENE,TOLUENE,PHENOL etc.) which are not completely oxidized in the reaction.
		allowed to grow on media, which is exposed	Ø COD is a chemical oxidation reaction
		to atmospheric air. It is also known as rotating	Ø Ammonia will not be oxidized.
		biological contactor (RBC).
		It is suitable for smaller capacities and does	Total Suspended Solids
		not require skilled labour to handle. The	Ø Total suspended solids(TSS) include all particles suspended in water which will pass through a filter.
		quality of treatment is good.
		e) Fluidized bio-bed reactor (FBBR) — In this	Ø As levels of TSS increase, a water body begins to lose its ability to support a diversity of aquatic life.
		process,  cells  are  immobilized  in  small	Suspended solids absorb heat from sunlight, which increases water temperature and subsequently decreases levels of dissolved oxygen(warmer water holds less oxygen than cooler water
		particles which move with the fluid. The small
		particles create a large surface area for cells	Components of Sewage Treatment
		to stick and enable a high rate of transfer of	Plants
		oxygen and nutrients to the cells. It is also	•           Pumping of Sewage
		known as moving bed bio reactor (MBBR). It	•           Primary Treatment
		is suitable for all type of communities, does	•           Secondary treatment
		not require skilled labour and requires less	•           Tertiary Treatment
		space. It can be installed for all capacities and
		the quality of treatment is good.	Pumping Station
			•        Receiving Chamber
		f) Submerged  aerobic  fixed  film  reactor	•        Coarse Screening
		(SAFF) — It is a combined growth process in	•        Wet Well (Raw Sewage Sump)
		allowed to grow on media, which has air	•        Pump House
		supply from below.	•        Raw Sewage Pumps
		It does not require skilled labour. Supporting
		structure for media should be anti-corrosive
		to enable media fixing.
		g) Trickling filters — It is an attached growth
		process where media is used to grow bacteria
		by trickling sewage over the media. It is an
		old concept and is not now widely used.
		h) Oxidation ponds/lagoons  Oxidation ponds,
		also called lagoons or stabilization ponds are
		large  shallow  ponds  designed  to  treat
		wastewater through the interaction of sunlight,
		bacteria, and algae.
	What is biological treatment of wastewater?	Biological treatments rely on bacteria, nematodes, or other small organisms to break down organic wastes using normal cellular processes. Wastewater typically contains a buffet of organic matter, such as garbage, wastes, and partially digested foods. It may also contain pathogenic organisms, heavy metals, and toxins	Step by Step Wastewater Treatment Process
	What do sewage treatment plants do?	Sewage treatment is the process of removing contaminants from wastewater and household sewage water. Click here for our range of sewage treatment plants. ... Its aim is to produce an environmentally safe sewage water, called effluent, and a solid waste, called sludge or biosolids, suitable for disposal or reuse.	1. Wastewater Collection
	What are the 3 stages of sewage treatment?	Sewage treatment generally involves three stages, called primary, secondary and tertiary treatment. Primary treatment consists of temporarily holding the sewage in a quiescent basin where heavy solids can settle to the bottom while oil, grease and lighter solids float to the surface	This is the first step in waste water treatment process. Collection systems are put in place by municipal administration, home owners as well as business owners to ensure that all the wastewater is collected and directed to a central point. This water is then directed to a treatment plant using underground drainage systems or by exhauster tracks owned and operated by business people. The transportation of wastewater should however be done under hygienic conditions. The pipes or tracks should be leak proof and the people offering the exhausting services should wear protective clothing.
	What are the steps of wastewater treatment plant?	Treatment Steps	2. Odor Control
		Step 1: Screening and Pumping. ...	At the treatment plant, odor control is very important. Wastewater contains a lot of dirty substances that cause a foul smell over time. To ensure that the surrounding areas are free of the foul smell, odor treatment processes are initiated at the treatment plant. All odor sources are contained and treated using chemicals to neutralize the foul smell producing elements. It is the first wastewater treatment plant process and it’s very important.
		Step 2: Grit Removal. ...	3. Screening
		Step 3: Primary Settling. ...	This is the next step in wastewater treatment process. Screening involves the removal of large objects for example nappies, cotton buds, plastics, diapers, rags, sanitary items, nappies, face wipes, broken bottles or bottle tops that in one way or another may damage the equipment. Failure to observe this step, results in constant machine and equipment problems. Specially designed equipment is used to get rid of grit that is usually washed down into the sewer lines by rainwater. The solid wastes removed from the wastewater are then transported and disposed off in landfills.
		Step 4: Aeration / Activated Sludge. ...	4. Primary Treatment
		Step 5: Secondary Settling. ...	This process involves the separation of macrobiotic solid matter from the wastewater. Primary treatment is done by pouring the wastewater into big tanks for the solid matter to settle at the surface of the tanks. The sludge, the solid waste that settles at the surface of the tanks, is removed by large scrappers and is pushed to the center of the cylindrical tanks and later pumped out of the tanks for further treatment. The remaining water is then pumped for secondary treatment.
		Step 6: Filtration. ...	5. Secondary Treatment
		Step 7: Disinfection. ...	Also known as the activated sludge process, the secondary treatment stage involves adding seed sludge to the wastewater to ensure that is broken down further. Air is first pumped into huge aeration tanks which mix the wastewater with the seed sludge which is basically small amount of sludge, which fuels the growth of bacteria that uses oxygen and the growth of other small microorganisms that consume the remaining organic matter. This process leads to the production of large particles that settle down at the bottom of the huge tanks. The wastewater passes through the large tanks for a period of 3-6 hours
		Step 8: Oxygen Uptake.	6. Bio-solids handling
	What is wastewater treatment definition?	Links. Sewage Treatment, Or Domestic Wastewater Treatment:: Sewage treatment, or domestic wastewater treatment, is the process of removing contaminants from wastewater, both runoff (effluents) and domestic. It includes physical, chemical and biological processes to remove physical, chemical and biological contaminants	The solid matter that settle out after the primary and secondary treatment stages are directed to digesters. The digesters are heated at room temperature. The solid wastes are then treated for a month where they undergo anaerobic digestion. During this process, methane gases are produced and there is a formation of nutrient rich bio-solids which are recycled and dewatered into local firms. The methane gas formed is usually used as a source of energy at the treatment plants. It can be used to produce electricity in engines or to simply drive plant equipment. This gas can also be used in boilers to generate heat for digesters.
	What are types of wastewater?	Types and sources of wastewater. Wastewater comes in three main types namely Blackwater, Graywater and Yellow water. This is wastewater that originates from toilet fixtures, dishwashers, and food preparation sinks. It is made up of all the things that you can imagine going down the toilets, bath and sink drains	7. Tertiary treatment
			This stage is similar to the one used by drinking water treatment plants which clean raw water for drinking purposes. The tertiary treatment stage has the ability to remove up to 99 percent of the impurities from the wastewater. This produces effluent water that is close to drinking water quality. Unfortunately, this process tends to be a bit expensive as it requires special equipment, well trained and highly skilled equipment operators, chemicals and a steady energy supply. All these are not readily available.
			8. Disinfection
			After the primary treatment stage and the secondary treatment process, there are still some diseases causing organisms in the remaining treated wastewater. To eliminate them, the wastewater must be disinfected for at least 20-25 minutes in tanks that contain a mixture of chlorine and sodium hypochlorite. The disinfection process is an integral part of the treatment process because it guards the health of the animals and the local people who use the water for other purposes. The effluent (treated waste water) is later released into the environment through the local water ways.
			9. Sludge Treatment
			The sludge that is produced and collected during the primary and secondary treatment processes requires concentration and thickening to enable further processing. It is put into thickening tanks that allow it to settle down and later separates from the water. This process can take up to 24 hours. The remaining water is collected and sent back to the huge aeration tanks for further treatment. The sludge is then treated and sent back into the environment and can be used for agricultural use.
			Wastewater treatment has a number of benefits. For example, wastewater treatment ensures that the environment is kept clean, there is no water pollution, makes use of the most important natural resource; water, the treated water can be used for cooling machines in factories and industries, prevents the outbreak of waterborne diseases and most importantly, it ensures that there is adequate water for other purposes like irrigation.
			Conclusion
			In summary, wastewater treatment process is one of the most important environmental conservation processes that should be encouraged worldwide. Most wastewater treatment plants treat wastewater from homes and business places. Industrial plant, refineries and manufacturing plants wastewater is usually treated at the onsite facilities. These facilities are designed to ensure that the wastewater is treated before it can be released to the local environment. Some of the water is used for cooling the machines within the plants and treated again. They try to ensure that nothing is lost. It illegal for disposing untreated wastewater into rivers, lakes, oceans or into the environment and if found culpable one can be prosecuted.

Drainage & Sanitation System MEP

IDENTIFICATION OF DRAINAGE & SANITATION
S.NO	Name	Description	Particular
	Drainage	— A sanitary drainage system consists of a building	FT-Floor Trap
		sewer, a building drain, a soil and/or waste stack, horizontal	BT- Bottle Trap
		branches or fixture drain, and vents. The sanitary drainage of a	GT- Guly Trap
		large building may have a number of primary and secondary	Cowl
		branches, and several soil and/or waste stacks, each of them in	Mixer
		turn may have a number of horizontal branches.	Common Soil/Waste Stack
			Vent Pipe
			Waste Stack
	Branch	a) Special form of sewer pipe used for making	P-Trap
		connections to a sewer or water main. The
		various types are called ‘T’, ‘Y’, ‘T-Y’, double
		Y  and  V  branches,  according  to  their
		respective shapes.
		b) Any part of a piping system other than a main	Drainage Plan
		or stack.	a) Every floor of the building in which the pipes
	Systems of Drainage	a)Combined system — A system in which foul	or drains are to be used;
		water (sewage) (black and grey water) and	b) The position, forms, level and arrangement of
		surface water are conveyed by the same sewers	the various parts of such building, including
		and drains.	the roof thereof;
		b) Separate system — A system in which foul	c) All new drains as proposed with their sizes
		water (sewage) (black and grey water) and	and gradients;
		surface water are conveyed by the separate	d) Invert levels of the proposed drains with
		sewers and drains.	corresponding ground levels;
		c) Partially separate system — A modification surface  water  is  conveyed  by  the  foul (sanitary) sewers and drains.	e) The position of every manhole, gully, soil and
			waste pipe, vent pipe, rainwater pipe, water
	Types of Sanitary Appliances	It shall essentially consist of a closet consisting of a	closet, urinal, latrine, bath, lavatory, sink, trap
	Soil Appliances	bowl to receive excretory matter, trap and a flushing	or other appliances in the premises proposed
	Water closet	apparatus. It is recommended to provide ablution tap	to be connected to any drain and the following
		adjacent to the water closet, preferably on right hand	colours  are  recommended  for  indicating
		side wall. The various types/style of water closets may	sewers, waste water pipes, rainwater pipes an
		be:	existing work:
		a) Squatting Indian type water closet,	Description of Work                                               Colour
		b) Washdown type water closet,	Sewers                                                                           Red
		c) Siphonic washdown type water closet, and	Waste water pipes                                                    Blue
		d) Universal or Anglo-Indian water closet.	rainwater pipes                                                          Blue
			Existing work                                                               Black
			f) The position of refuse chute, inlet hopper and
	Urinal	It is a soil appliance for urination and is connected to	collection chamber.
		soil pipe after a suitable trap. Urinal should have	Testing
		adequate provision of flushing apparatus. The various	The plumbing system shall be subjected to required
		types/style of urinal may be:	tests to effectively disclose all leaks and defects in the
		a) Bowl type urinal: flat back or angle back.	work or the material.
		b) Slab (single) type urinal.
		c) Stall (single) type urinal.
		d) Squatting plate type urinal.
		e) Syphon jet urinal with integral trap.
		f) Water less (non-water) urinal
	Efficient and an economical plumbing system	a) Placing of plumbing fixtures around an easily	Additional requirements
	can be achieved by planning the toilets in compact	accessible pipe shaft; in high rise buildings
	grouping with  the  layout  of  the  bathrooms  and	the pipe shafts may have to be within the	a) The layout shall be as simple and direct as
	observing the following guidelines:	building envelope and easy provision for	practicable.
		access panels and doors should be planned in	b) The pipes should be laid in straight lines, as
		advance, in such cases so as not to cause	far as possible, in both vertical and horizontal
		inconvenience during maintenance.	planes.
		b) Adopting repetitive layout of toilets in the	c) Anything that is likely to cause irregularity of
		horizontal and vertical directions.	flow, such as abrupt changes of direction, shall
		c) In planning for malls, the required public and	be avoided.
		toilet facilities shall be located not more than	d) The pipes should be non-absorbent, durable,
		one storey above or below the space to be	smooth in bore and of adequate strength.
		served with such facilities, and the path of	e) The pipes should be adequately supported
		travel to such facilities shall not exceed 91 m.	without restricting movement.
		toilet facilities shall be located not more than	f) Drains should be well ventilated, to prevent
		one storey above or below the space to be	the accumulation of foul gases and fluctuation
		served with such facilities, and the path of	of air pressure within the pipe, which could
		travel  to  such  facilities  shall  not  exceed	lead to unsealing (siphoning) of gully or water
		152 m.	closet traps.
		However, in the above buildings, toilet rooms	g) All the parts of the drainage system should be
		shall not open directly into a room used for	accessible for feasibility of inspection and
		preparation of food for service to public.	practical maintenance.
		j) Usually, the vertical distance between two	h) No bends and junctions whatsoever shall be
		horizontal connections to a vertical drain	permitted in sewers except at manholes and
		should be more than 200 mm in order to avoid	inspection chambers.
		back flow.	j) Sewer drain shall be laid for self-cleaning
		d) Avoiding any conflict with the reinforced	velocity of 0.75 m/s and generally should not
		cement  concrete  structure  by  avoiding	flow more than half-full.
		embedding pipes in it, avoiding pipe crossings	k) Pipes crossing in walls and floors shall be
		in  beams,  columns  and major  structural	through mild steel sleeves of diameter leaving
		elements.	an annular space of 5 mm around the outer
		e) Identifying open terraces and areas subject	diameter of the pipe crossing the wall.
		to ingress of rainwater directly or indirectly
		and providing for location of inlets at each	m) Pipes should not be laid close to building
		level for down takes for disposal at ground	foundation.
		levels.	n) Pipes should not pass near large trees because
		f) Avoiding crossing of services of individual	of possibility of damage by the roots.
		property through property of other owners.	p) Branch connections should be swept in the
		g) Planning to avoid accumulation of rainwater	direction of flow.
		or any backflow from sewers particularly in	q) Sewer pipes should be at least 900 mm below
		planned low elevation areas in a building.	road and at least 600 mm below fields and
		h) Setting of sanitary fixtures — A water closet,	gardens.
		urinal, lavatory or bidet shall not be set closer	r) Pipes should not pass under a building unless
		than 380 mm from the centre to any side wall	Preliminary Data for Design
		partition, vanity or other obstruction, or closer	a) Site plan
		than  760 mm  centre-to-centre  between	b) Drainage plan
		adjacent fixtures. There shall not be less than	c) Use —
		530 mm clearance in front of the water closet,	d) Nature of waste —
		urinal, lavatory or bidet to any wall, fixture or	e)Outlet  connection —
		door. Water closet compartment shall not be	f)Cover
		less than 760 mm in width and 1 520 mm in	g)Cover
		depth for floor mounted closets, and not less	h)Subsoil condition
		than 760 mm in width and 1 420 mm in depth	The minimum internal diameter for sanitary
		for wall hung water closets.	appliances shall be as follows:
		The urinal partitions shall begin at a height	Sanitary Appliance                        Minimum Internal dia    waste outlet(mm)
		not greater than 305 mm from and extend not	i)  Soil appliances:
		less than 1 520 mm above the finished floor	a)  Indian and European type
		surface. The walls or partitions shall extend	water closets
		from the wall surface at each side of the urinal	100
		not less than 460 mm or to a point not less	b) Bed pan washers and slop
		than 150 mm beyond the outermost front lip	sinks
		of the urinal measured from the finished back	100
		wall surface, whichever is greater.	c) Urinal with integral traps                                                                        75
			d) Stall urinals (with not                                                                             50
			more than 120 mm of
			channel drainage)
			e)  Lipped urinal small/large                                                                      40
			ii)  Waste appliances:
			a) Drinking fountain                                                                                     25
			b) Washbasin                                                                                                  32
			c)  Bidets                                                                                                            32
			d) Domestic sinks and baths                                                                      40
			e)  Shower bath trays                                                                                   40
			f)  Domestic bath tubs                                                                                 50
			g) Hotel and canteen sinks                                                                        50
			h) Floor traps (outlet dia)                                                                          75