Construction of Giresun Wastewater Treatment Plant  Tender Dossier Volume 3 Employer’s Requirements  Section 3: Plant Description  30 of 74  Figure 3-1. 3.3.4.18  Blowers for Aeration  The discharge pipe shall be constructed on the route between Batlama Sanayi Street and left bank of  Batlama Creek and discharge into Black Sea coast near the mouth of Batlama Creek after crossing the  Blacksea Coastal Highway. Outfall structure shall be constructed on existing rock embankment and  necessary precautions shall be taken to protect discharge pipe and structure against negative impacts of  river and sea. The discharge pipeline and outfall structure shall be designed by the Contractor and shall  be submitted to the approval of the Engineer.  The power distribution panel and MCCs for blowers shall be placed in a different room other than the  blowers. Number of blowers shall be determined in such a way that minimum each blower serve one  aeration tank. In addition to this, one stand by blower shall be provided. The oxygen and air  requirements of biological process during the first years of operation (e.g. 2022) shall be taken into  consideration in determination of capacity of blowers. The blowers shall be located close to the  activated sludge tanks in a building to protect the equipment against the weather conditions and to  protect the environment against the noise generated by the blowers.  The aeration equipment capacities shall be in such amount to keep the minimum oxygen concentration  in the aeration tanks 2 mg/l. The blower capacity calculation has to be based on internationally  accepted design standards or ATV-DVWK-A 131E Standard (German Association for Water  Pollution Control). The blowers shall be of the air bearing or magnetic bearing type or integrally geared centrifugal type  with servo operated variable diffusers and servo-operated variable pre-rotation systems for maximum  efficiency. All blowers will be equipped with motor, frequency converter, air inlet filter, support,  accosting hood, non-return valve and flexible discharge connection, safety valve and pressure gauge.  Individual blower shall be switched “ON/OFF”, in case of blower failure and also in order to equalize  hours of operation, hours of individual blower an automatic changeover “Duty/Standby” shall be  provided. At the each blower discharge pipeline, isolating valve shall be provided. Type of valves  must be suitable for air applications. In order to discharge the compressed air between the non-return  (check) valve and blower, a blow off valve and its pipeline shall be installed on outlet of each blowers.  Type of blow off valve shall be solenoid, pneumatic or actuator controlled. There shall be a  thermometer and a manometer on common pressure pipeline of blowers. These instruments shall be  controlled and monitored by the SCADA system. The blowers and auxiliaries proposed by the  Contractor shall be in accordance with the specifications given in Section 7.8.31.  The blowers shall be supplied with silencer hoods or cabinet. The maximum acceptable noise level in  the blower room shall be maximum 85 dB. Special attention shall be given to the air inlet system, and  the temperature in the blower building shall be calculated and necessary measures shall be taken.  The blower room shall be provided with a travelling overhead crane for installation and service  requirements.  The blowers shall be autonomous and locally controlled. The set point for the oxygen shall be  controlled by the SCADA system which shall also monitor the operation of the blowers.  3_Vol3_d4.3_Section 3_Plant Description_GIR_rev08 