Combination Fine and Coarse Bubble Diffused Aeration System

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1 1.0 General 1.1. The following specification sections refer to a combination fine and coarse bubble diffused aeration system. The function of this system is to provide adequate oxygen transfer in accordance with the specified transfer rate, provide adequate mixing power to maintain solids in suspension, and minimize the quantity of fine bubble elastomeric membranes and related maintenance The basis of design for this system is Tideflex Technologies Combination Aeration System, this is a patented system and process therefore no alternate combination systems will be accepted. Alternate coarse bubble aeration systems must comply with the specifications listed in this section for alternate diffusers. Alternate fine bubble diffused aeration systems will not be accepted as an alternate for this system The approved manufacturer for this system to be included within the Base Bid shall be manufactured by Tideflex Technologies, Inc. Pittsburgh, PA Any other submittals intended as equivalent or alternate must be submitted prior to the Bid Date and be pre-approved by the Engineer prior to Bid opening. 2.0 Fine Bubble Diffusers 2.1. For specifications on individual fine bubble diffuser units refer to Section titled Fine Bubble Elastomeric Membrane Diffusers. 3.0 Coarse Bubble Diffusers 3.1. For specifications on individual fine bubble diffuser units refer to Section titled Coarse Bubble Elastomeric Diffusers. 4.0 Guidelines for Sizing 4.1. Refer to specifications section titled Diffused Aeration System Process Performance Requirements for overall system process requirements. 5.0 Distribution Manifold Orientations 5.1. The fine bubble manifolds and coarse bubble manifolds shall be arranged as specified by Tideflex Technologies to optimize mixing and oxygen transfer. 6.0 Airflow Indicator Equipment 6.1. The Aeration System manufacturer shall provide pressure differential assemblies consisting of 316 stainless steel pitot tubes, magnehelic Print Date: 06/27/

2 gauge, pressure tubing, conversion chart, and Nema-4X enclosure with handrail mounting hardware as specified within the specifications section titled Airflow Indication Equipment. 7.0 Flow Control Valves 7.1. The main air supply line for each individual tank shall include a tee for supplying individual air supply lines to the fine bubble system and to the coarse bubble system. The tee and pipes shall be sized in accordance to the airflow capacities of each system Each dedicated air supply line shall have a manual / automatic variable orifice flow control valve Cylinder Operated Automatic Control Valve Valves shall be of the full cast metal body, mechanical pinch type with flange joint ends. The valve length shall be as given in ISA S The flanges shall be drilled and tapped to mate with ANSI B16.1, Class 125 / ANSI B16.5, Class 150 flanges The sleeve trim shall be one piece construction with integral flanges drilled to be retained by the flange bolts. The sleeve trim shall be reinforced with calendared nylon or calendared polyester fabric to match service conditions. The sleeve trim shall be connected to the pinch bar by tabs imbedded in the sleeve trim reinforcing ply. All internal valve metal parts are to be completely isolated from the process fluid by the sleeve trim. For full port and reduced port sleeves the port areas shall be 100% of the full pipe area at the valve ends. For Cone and Variable Orifice sleeves the port area at the inlet shall be 100% of the full pipe area, reducing to a smaller port size at the outlet The solid steel mechanism shall be single acting, closing the sleeve trim from the top only. The mechanism shall be supported in the valve body. There shall be no cast parts in the operating mechanism. The pinch mechanism shall be adjustable for stroke without removing the valve from the line. The mechanism shall be connected to the cylinder actuator by a stainless steel stem The pneumatic cylinder actuator shall be manufactured utilizing black Amalgon cylinder tubing. The cylinder is to have a working pressure of 150 psi. The spring for direction fail systems, when specified, shall be fully enclosed in the cylinder housing. The cylinder assembly shall be mounted on the valve body by means of an open yoke. Print Date: 06/27/

3 The yoke shall be used to mount limit switches, valve positioner, stem position indicator and /or other accessories. The positioner shall be a high gain, cam characterizable, pilot directed, pneumatic or electro-pneumatic type. All accessories shall be factory set and field adjustable. Valve shall be manufactured in the USA Manually Operated Flow Control Valve Valves are to be of the full cast metal body, mechanical pinch type with flange joint ends on both the body and the sleeve trim. The valve shall have face-to-face dimensions of standard gate valves, in accordance with ANSI B16.10 up to 12 size. Sizes 14 and larger shall have a face to face dimension no longer than twice the nominal valve port diameter. The flanges shall be drilled to mate with ANSI B16.1, Class 125/ANSI B16.5, Class 150 flanges The sleeve trim shall be one piece construction with integral flanges drilled to be retained by the flange bolts. The sleeve trim shall be reinforced with calendared nylon or calendared polyester fabric to match service conditions. The sleeve trim shall be connected to the pinch bar by tabs imbedded in the sleeve trim reinforcing ply. All internal valve metal parts are to be completely isolated from the process fluid by the sleeve trim For full port and reduced port sleeves, the port areas shall be 100% of the full pipe area at the valve ends. For Cone and Variable Orifice sleeves the inlet port area shall be 100% of the full pipe area, reducing to a smaller port at the outlet The steel mechanism shall be double acting with pinching of the sleeve trim occurring equally from two sides. ACME threads shall be used on all valve mechanisms. There shall be no cast parts in the operating mechanism. The stem shall be non-rising and have a non-rising handwheel. Valve position indication shall be in the center of the stem. Mechanism lubrication fittings shall be provided. Bevel gear operators shall be provided on all valves over 8" size. 8.0 Alternate Equipment 8.1. Equipment other than the specified Base Bid Equipment shall be considered an alternate and must comply with the following specifications and requirements. Alternate equipment shall be listed separately on the Bid Form as an alternate add or alternate deduct in the areas provided or written in and designated accordingly. The manufacturer of the alternate equipment must be indicated and accompanied with a detailed equipment itemization. Alternate equipment must comply with all material and Print Date: 06/27/

4 equipment specifications as defined within the base bid specifications as well as the specifications listed within this section Stainless steel tube diffusers with open orifices shall provide the following ancillary equipment. In order to provide the equivalent backflow prevention capability as the base bid equipment the alternate equipment manufacturer shall provide ancillary backflow prevention with a supplemental check valve. A ball check valve shall be supplied for each diffuser between the diffuser and the tee assembly. The ball valves provided shall be in accordance with the following specification The diffuser shall be capable of withstanding an impact load of 100 pounds against the discharge tapered end of the diffuser, deflect to a minimum allowance of 45 degrees and recover to the normal operating position. If stainless steel (horizontal mount) tube type diffusers are supplied then the associated piping material required shall be schedule L stainless steel, to ensure pipe integrity from loads to the cantilevered connection, in lieu of any plastic piping specified or shown on the drawings. Stainless steel diffusers shall be constructed of 316L stainless steel with a minimum gauge thickness of throughout the entire housing. Units less than this minimum gauge thickness shall be equipped with a ½ diameter 316L SS rod continuously welded along the top edge of the diffuser unit, across the entire length of the diffuser, to resist bending of the unit from loading on the cantilevered free end Ball check valve specification; all components of the valve shall be constructed of 316L stainless steel. End ports shall be ¾ FIPT. Valve shall have a maximum operating pressure capacity of 50 psi Elastomeric membrane diffusers are not considered as an equivalent and shall not be submitted as an alternate The Contractor shall include within their Bid the following documents to ensure compliance of their intended equipment submittal; Equipment Manufacturer s process calculations showing compliance and ability to achieve the required operating performance, Equipment manufacturer s oxygen transfer curves for percent efficiency versus airflow at the specified operating depth or proposed diffuser submergence depth, Equipment Manufacturer s diffuser headloss curves including orifice regulator headloss, Print Date: 06/27/

5 9.0 Submittals Equipment Manufacturer s diffuser arrangement plan showing diffuser spacing from row to row and diffuser to diffuser The aeration equipment manufacturer shall supply to the Engineer the Certified Oxygen Transfer Curve for the applied fine and coarse bubble diffuser The aeration equipment manufacturer shall supply to the Engineer the Certified Diffuser Headloss Curve for the applied fine and coarse bubble diffuser Installation Diffusers shall be installed in accordance with the installation guidelines supplied by the aeration system manufacturer Start-Up Procedures Start-up procedures shall be outlined in the Installation, Operation and Maintenance Manual provided by the aeration equipment manufacturer Spare Parts The aeration manufacturer shall supply [ ] spare diffuser assemblies, equipped with elastomer nozzle, PVC reducer bushing, and ¾ stainless steel NPT nipple pre-assembled and ready for installation The aeration manufacturer shall supply [ ] spare diffuser assemblies, equipped with elastomer membrane, internal check valve, and ¾ schedule 80 PVC NPT nipple pre-assembled and ready for installation The aeration manufacturer shall supply [ ] membrane replacement kits which consist of one elastomer, perforated membrane and two stainless steel crimp clamps. Additionally, [ ] crimp tool(s) shall be provided Warranty The coarse bubble diffusers assemblies shall be warranted by the aeration manufacturer against failure under design conditions for a period on one (1) year from the date of final installation approval by the Engineer. Print Date: 06/27/

6 13.2. Elastomer Diffuser shall be warranted by the aeration manufacturer against failure under design operating conditions for a period of one (1) year from the date of final installation approval by the Engineer. Elastomer components damaged as a result of maintenance activities, foreign debris in the process solution, or excessive exposure to direct ultraviolet and thermal radiation shall be excluded warranted coverage The fine bubble diffuser assemblies shall be warranted by the aeration manufacturer against failure under design conditions for a period on one (1) year from the date of final installation approval by the Engineer Elastomer Diffuser membranes shall be warranted by the aeration manufacturer against failure under design operating conditions for a period of one (1) year from the date of final installation approval by the Engineer. Elastomer components damaged as a result of maintenance activities, foreign debris in the process solution, or excessive exposure to direct ultraviolet and thermal radiation shall be excluded warranted coverage. End of Section Contact Valve and Equipment for Microsoft Word Versions of this document Valve & Equipment Consultants, Inc Yoakum St Huffman, TX Phone: Fax sales@valveandequipment.comt Web Site: Print Date: 06/27/