PERIODICAL SERVICES /MAINTENANCE OF SEWAGE TREATMENT PLANTS AND FIRE FIGHTING SYSTEMS OTHER MISC WORKS AT DOMESTIC AND TECHNICAL AREA

Comprehensive maintenance /repair of sewage treatment plant capacity of 0.05 MLD including minor repairs, the plant comprising of the following :- Main collection tank of 30,000 ltr capacity, submersible sewage pump of capacity 7.5HP 3 phase 415V - 02 No, Non-clogging pump 1HP 3 phase 415V – 01 No, Aeration tank, Filter feed pump air blower 7.5HP 3 phase 415V – 01 No, Activated carbon filter tank with assembly – 01 No, Hypo chlorine dozing system – 01 No, Sand filter tank assembly – 01 No, recirculation pump 3HP 3 phase 415V – 01 No, open well submersible pump 5HP, 3 phase, 415V – 01 No and other civil structures/ chambers, connected equipments, panels, cables etc.

(I) The parameters of input and output shall be maintained as under :- (a) Inlet parameters: (i) BOD - 250 - 275 mg/ltr (ii) COD - 400 - 550 mg/ltr (iii) TSS - 400 mg/ltr (iv) PH - 7 to 7.5 (v) Fecal Coliform - < 230

(b) Parameters for treated sewage effluent required are as: (i) PH - 6.5 to 9.0 (ii) BOD - Less than or equal to 30 mg/ltr (iii) TSS - < 100 mg/ltr (iv) Fecal coliform - Less than or equal to 100 counts/100 ml

(II) The following daily maintenance to be carried out :- (a) Bar screen chamber should be cleaned every day to ensure that it’s not choked. (b) Cleaning of Oil & Grease trap. (c) Once in every two hours pumps should be changed between working and standby i.e, Sewage feed pump, blower and Filter feed pump. (d) Maintain disinfection liquid in chlorine dozing tank. (e) MGF and AGF back wash & rinse – Once in every 8 hours simultaneously. (f) Settling tank - Sludge should be disposed from settling tank to sludge drying bed. Once every 8 hours based on MLSS growth. (g) Monitoring and maintenance of log books periodically. (h) Treated water tank - chlorine content should be analysed to ensure that chlorine % is below 0.2 ppm. (j) MLSS growth - to be checked in aeration tank and equalization .

(III) The following weekly maintenance to be carried out :- A STP system is inspected weekly and the following points attended to :- (i) Inspect Equalisation Tank/ Entry to system for blockages, plastics etc and remove. (ii) Inspect Aerator and note biomass growth, recirculation flow and if any malodour, it is to be treated. (iii) Inspect Secondary clarifier (Humus, Tank) and note visual appearance of final effluent and absence (or otherwise) of sludge build up. (iv) Check the outlet of the system for blockage etc. (v) Check water level in grease trap and if required top up with clean cold water. (vi) Grease the bearings (vii) Grease all chain couplings through casing nipples. (viii) Drain out and replace gearbox oil of superior quality (ix) Check holding plate bolts. (x) Check shaft for wear and alignment. (xi) Check bearings for wear and tear and check holding down bolts for tightness. (xii) Check chain coupling and check bolts for tightness.

(IV) The following monthly maintenance to be carried out :- Aerator MUST BE SWITCHED OFF during monthly maintenance procedures. Refer weekly maintenance schedule and follow the below mentioned instructions. (i) Check motor for overheating (by touch) and remove dust etc. from air fins. (ii) Grease all bearings through nipples. (iii) Grease all chain couplings through casing nipples. (iv) Check oil level in gearbox and top up if necessary. (v) Check sludge return system from Humus Tank for function. (vi) Apply light lubricating oil in small quantities to locks and hinges. (vii) Empty and clean out grease trap and fill with clean cold water. (viii) Preparing and submitting monthly report on performance of the plant. (ix) Sludge disposal outside the MD land atleast once in a month. (x) Check and calibrate the instruments including on line monitor and submit report. (xi) Check dozing pump and repair/service if necessary.

(V) The following items for routine maintenance shall be provided in plant for satisfactory result that treated water required :- (a) Liquid chlorine (b) Urea (c) DAB (d) Cow dung (e) Defoaming chemical (f) Caustic Soda

(VI) The following items shall be replaced as and when required or as directed by the Engr-in-Charge:- (a) Gaskets and Gland Packing. (b) 'O' rings. (c) Drive belts for air blower and clarifier. (d) Minor electrical accessories viz Indication lamps, fuses etc. (e) Blades (f) Pasting materials (g) Consumables like gloves, safety jackets, helmets, respirators etc (h) Cleaning Chemicals, reagents, Lubricants etc. (j) Contractor shall ensure the filter media particles are upto the level in ACF and MGF. If the quantity level reduces due to loss during filtration and back wash, the same should be toped up during routine maintenance.

(VII) The following tests shall be carried out and maintain the record of treated sewage as per frequency mentioned below :- Ser No Description of parameters Periodicity 1. PH Daily 2. TSS Monthly 3. BOD Monthly 4. COD Monthly 5. Coliform Monthly 6. Residual chlorine Daily 7. Dissolved oxygen Monthly

Comprehensive maintenance/repair of sewage treatment plant of capacity of 1 MLD, the plant comprising of the following assets:- Main collection tank of 2,00,000 ltr capacity, submersible sewage cutter pump of capacity 7.5HP 3 phase 415V-02 No, air compressor 15HP, 3 phase 415V - 03 Nos, treated water monoblock pump set 15HP, 3 phase 415V - 02 Nos, treated water submersible type motor 7.5HP, 3 phase 415V - 02 Nos, clarifier motor and gear 2 HP, 3 phase, 415V - 01 Nos, activated carbon filter tank with assembly - 01 Nos, sand filter unit - 01 Nos, settling tank - 01 Nos, Aeration tank - 02 Nos, treated water sump of 5000 ltr capacity - 01 Nos, chlorine tank of 20000 ltr capacity - 01 Nos, secondary clarifier - 01 Nos, sludge drying bed divided into 04 Nos compartment - 01 Nos, PLC based fully automatic SCADA panel-01 Nos, motorised valve 100 mm - 04 Nos, LT panel with motor controller - 01 Nos, recycling pump 5HP, 3phase, 415 volts - 02 Nos and other civil structures /chambers, connected equipments, control panel board and cables etc. The parameters of input and output shall be maintained as under :-