3.1 Design Conditions and Principles
3.1.1 Equipment Name: Hot Network补水Deaerator
3.1.2 Equipment Purpose: Directly heats through steam to remove dissolved oxygen and other non-condensable gases from the hot water network make-up (25℃), achieving the required water quality for the make-up.
3.1.3 Equipment Configuration: This phase of the project includes 1 thermal network make-up deaerator.
3.1.4 Type: Vertical deaerator, horizontal water tank.
3.2 Equipment Specifications
3.2.1 Equipment-related Parameters
Technical Requirements
4.1 Equipment Performance Requirements
All equipment in this technical agreement must be designed according to the design standards for pressure vessels, with a service life of not less than 30 years.
4.1.2 Oxygen Removal Performance Requirements for Hot Network Deaerator
The deaerator heats the chemically softened water to the saturation temperature under the deaerator operating pressure by direct steam heating, in order to remove dissolved oxygen and other non-condensable gases from the demineralized water, achieving the required water quality.
4.1.2.1 The outlet pipe diameter of the hydrogen separator's storage tank should be capable of accommodating the maximum water supply flow rate, with the pipe size designed within the allowable medium flow rate range when the water supply is at full load. To ensure all accumulated water in the tank is drained, the oxygen separator's storage tank should be equipped with an adequate number of drain pipes of appropriate diameter at the bottom.
4.1.2.2 The feedwater treated by the dehydrogenator should not exceed 15 Ug/L in dissolved oxygen content, and all free carbon dioxide and other non-condensable gases should be removed from the well.
4.1.2.3 Bidders in the deaerator design should not only meet the requirements of section 4.1.4 but also take into account the following points:
The deaerator should be equipped with a steam-water separator or area to ensure stable operation and achieve the required performance.
(2) The deviation of the effluent from the degasser after deoxygenation should be as small as possible, and the bidder should provide the numerical value of this deviation in the bid document.
4.1.2.4 Under normal circumstances, the deaerator operates at a constant pressure. The deaerator should be able to operate safely during abnormal or failure conditions.
To ensure the safe operation of the power plant, the design of the deaerator (including auxiliary equipment) should be capable of withstanding the most adverse combination of loads that may exist under all operating conditions of the power plant. The loads considered in the design should at least include:
(1) Internal and external design pressures;
(2) Normal water weight of components during storage or operation or testing.
(3) Additional Loads. Such as platform escalators, pipelines, and insulation, etc.
Earthquake Loadings
(5) Reaction force from the water tank bracket
(6) Counterforce of the safety door's action.
4.1.2.6 The equipment's interface should be capable of withstanding reactive forces and moments transmitted from the bidder's pipeline, with the resultant forces and moments to be assumed as acting simultaneously.
4.1.2.7 If the bidder's equipment fails to meet the specified interface load requirements, the bidder shall specify the force and torque each equipment interface can withstand and provide it to the tenderer for approval.
4.1.2.8 In addition to considering the specified interface load requirements, an appropriate margin should be left to fully estimate the changes that may arise from the bidder's pipeline redesign.
4.1.2.9 If a safety valve is directly mounted on the deaerator, consider the counterforce (F), torque, and the effect of internal pressure when the safety valve opens and exhausts steam.
4.1.2.10 Consider the effect of sudden applied load (F), the applied forces and moments during the operation of the safety valve should also take into account the dynamic load coefficient related to the opening of the safety valve, which can be taken as 2.
4.1.2.11 The wall thickness of the short pipes, vessel shells (including the reinforcing plates at the short pipe locations), and flanges on the short pipes are all subject to strength calculations to withstand internal pressure, the operation of safety valves, reactive forces and moments, thermal expansion thrust, and the weight of the safety valves and exhaust pipes. Earthquake loads should also be considered.
4.1.2, The 12-pass deaerator is equipped with an electrically actuated steam regulating valve. The bidder is responsible for selecting and supplying the steam regulating valve for the deaerator. The regulating valve should include an electric actuator, both male and female flanges and their connecting parts, a transition section for the connection, and the specified connection size.Φ133x4, 20# steel material for pipe fittings.
