As an economizer definition; It means a heat exchanger that recovers this low temperature heat by reducing the flue gas temperature of any heat boiler and saves extra fuel. Although it is used in many other boiler types such as hot water boiler and hot oil boiler, the main area is steam boilers. Today, it is one of the indispensable units of especially large-capacity steam boilers.
Energy recovery with economizers is in a very critical position today in terms of both maintaining competitiveness by reducing costs and maintaining environmental awareness by reducing emissions. Economizers have an important place in terms of energy recovery, especially in boiler applications where fossil energy is consumed the most. The important thing here is to determine the right method by examining waste energy in terms of investment cost and recovery optimization. The most important parameter limiting the recovery in economizers is low temperature corrosion on the flue gas side..
EBy reducing the flue gas temperature in the economizer to operating conditions, an efficiency of approximately 5-10% is obtained.
Non condensing economizers
- Smooth tube economizers
- Serpentine tube economizers
---------------Wrapped serpentine tube economizers
---------------Continuous MIG-MAG welded serpentine tube economizers
Condensing economizers
- Smooth tube economizers
- Serpentine tube economizers
Some Useage Area
- Boiler Feed Water or Combustion Air Heating
- Process or Heating Water Production
- Additional Energy Recovery in Cogeneration Chimneys
- Recovery in Ship Engine Chimneys
- Recovery from Furnace Chimneys
Benefits of Using Economizer
Approximately every 21°C decrease in flue temperature means 1% fuel savings..
With condensing economizers, over 100% efficiency can be achieved by utilizing the upper heating value of the fuel.
Heating the boiler feed water increases the boiler life by preventing thermal shocks in the boiler as well as saving.
With less fuel consumption, less emissions to the atmosphere occur.
The same degree of heat recovery can be achieved by heating the combustion air.
RECUPERATOR
Recuperator systems are systems that increase energy efficiency, which are used to preheat the hot air that is needed by making use of the heat energy of the high temperature waste flue gas generated in furnace systems, boiler systems and various processes. They work on the principle of heat transfer from air to air, from gas to gas. Compared to economizers, they have larger surface area and dimensions at the same heat capacity. They can be manufactured as finned tube and smooth tube.
By reducing the flue gas temperature to operating conditions in recuperators, approximately 4%-8% efficiency is obtained.
Recuperators can be classified as condensing and non condensing. In condensing type recuperators, flue gas temperature can be decreased to 55C depending on the fuel type burned in the boiler. In non condensing type recuperators, recuperator flue gas output temperature should be considered as 180 C for fuel oil, 150 C for diesel fuel, 150 C for coal based fuels, 110 C for natural gas and LPG.
Recuperators can be designed as horizontal or vertical depending on the place of use. They can be produced without valve, with manual valve, with proportional valve (pneumatic actuator, electrical actuator, engine powered) depending on the usage location and customer requirement.
In recuperators, waste heat, boiler, operating pressure and safety scenarios have to be taken into consideration all together. In recuperator design, it has to be ensured that the pressure drops stay lower than the forecasted pressure drops for the system.
Recuperators according to their systems;
Non condensing recuperators
- • Smooth tube recuperators
Condensing recuperators
- • Smooth tube recuperators
Design and Manufacturing of Economizers and Recuperators
Thermodynamic calculations for economizers and recuperators are made with professional programs and design and mechanical calculations are made according to TEMA standard and 2014/68/EU PED (Pressure Equipment Directive) Pressure Vessel directive EN 12952 and EN 12953 standard. Body and heating tubes are made of materials manufactured in conformity with EN 10216 and EN 10217 manufacturing standards, tubesheet, cover and baffles are made of materials manufactured in conformity with EN 10025 and EN 10028 manufacturing standards, counter flanges are made of materials manufactured in conformity with EN 1092 manufacturing standard under fluid and pressure class. They are delivered to customers as painted according to customer request following hydrostatic pressure tests. Upon the request of the customer they are manufactured with CE certification by generating a quality information file.
All criteria in the directive (material certificates, WPS, WPQR, welding consumables certificates,technical drawings, thermodynamic calculations, mechanical calculations, RT-UT-MT-PT personnel information and test results, pressure test reports, measurement devices, calibration documents, risk analysis, conformity statement, basic safety requirements, operating manual, name plate with CE sign and stamp of the approved institution) are subject to inspection during various phases of production by approved institutions, and CE certificate and quality information file is delivered with the product showing the conformity of the design and the product being manufactured within the limits of the standard.
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