We Are Powercon Equipments And We Provide Best Service And Product
GAT NO.189, Jyotiba Nagar, Talwade, Pimpri Chinchwad-412114, Pune, Maharashtra, India
Gardenia Co- Op. Housing Society, Phase-1, Sixth Floor, Flat No.- 22, Vadagon Sheri, Pune - 412114, Maharashtra, India.
We POWERCON EQUIPMENTS here with introduces the details of designed manufactured system called BED-ASH HANDLING SYSTEM i.e., BED ASH COOLER.
Typical water cooled Holo-Screw Coolers provide proven reliability to drain and cool bed material from the CFBC /FBC. A typical Holo-Screw Cooler design is shown in Fig. 1. Hot ashes and some inert material such as sand discharges at the bottom of and enter the screw cooler through the flooded inlet. The hot product is then continuously conveyed into the discharge at an angle and dumped into the ash handling system.
Cooling of ash commences as soon as it comes in contact with a water-cooled surface such as the screw and the housing. Substantial exchange of heat occurs between the hot product and the rotating screw and housing.
Efficient cooling of product is accomplished by particle contact with the heat exchange surface, therefore, a relatively long total time of retention of the particle in contact with the rotor surfaces is required. Contact must be continuous and short duration, so that all particles may come in contact with the heat exchange surface area. The ideal condition would be for the product to be in a fluidized state and highly flowable.
POWERCON provides a wide range of models and types of Holo-Screw Coolers custom designed and built according to customer provided specifications.
Ash cooling screws are typically designed to handle boiler ash with a discharge temperature of up to 950 Degree C and cooling it down to 150 Degree C or less so it can enter the ash handling system.
Solid Stainless Steel Helicoid Flight construction at the inlet section of the screw rotor.
Hollow Flight construction is utilized on the remainder of the rotor.
Jacketed Housings Cross-Sections.
Jacketed housing increases the cooling capability of the processor. Increases the life expectancy of the housing by keeping the carbon steel in operational temperature limits.
The successful operation of a Hollow Screw Processor for cooling ash in Fluidized Bed Combustion Technologies is dependent upon the ability to overcome the extreme environment at the inlet section of the screw rotor.
Secondary in the design, you must consider the heat transfer capabilities of the processor as a time dependant variable and all factors must be taken in consideration. These factors vary from heat transfer surface area requirements, performance per square foot of area, fouling of the rotor due to ash build up and fouling of internal heat transfer area due to scale and oxidation.
ADVANTAGES OF WATER-COOLED SCREW COOLERS -
1) System Space Requirement -1000 mm x 4500 mm ( Depends on Inlet C‐C ) x 1500 mm ( It varies with System Layout -requirements)
2) Inlet & outlet Points - System / Single Water Cooled Bed Ash cooler can accommodate more than 1 inlet Point with flexibility to deliver point.( The delivery Point can be. extended on requirement of site location
3) Recycling of cooling Media Possibility - Water cooled bed Ash cooler media water can be recycled by Draining the same water in free Space tank and pumped once again .
4) Consumption of media used - Water cooled bed ash Cooler water can be consumed hardly by evaporation and loss of volume is 1 to 5 %
5) Effects on Boiler system - Water cooled bed Ash cooler works- independently and it has no connection with running of boiler , and drained water gets recycled independently , i.e. NO Process involved of Boiler. Thus Boiler efficiency does not affect by any menace , The Boiler can work independently even if The Bed Ash cooler under break Down and no need of stoppage of Boiler.
6) Effects on Boiler structure & internal parts of boiler and its efficiency - Water Cooled Bed ash cooler ,Water media is directly discharged to free space , does not affects any apart of boiler. Thus boiler efficiency does not affects anyway.
7) Effects on Season Time - Normally the ambient temp Water is used , hence there is no effects in operation of the system in any season.
8) System Operation ‐Programme - Water cooled System requires , few controls like ,Pressure of water , detection of water flow and rotation of Screw
9) Maintenance Cost - Mainly Damages take place to internal Screw after Long running Time , Approx. 10 years span , in such case Complete shaft may require to replace . In Normal course , greasing , bearing . Chain sprocket over all maintenance is required.
10) Material of construction - Normally The Water cooled systems are made through SS material , which anti corrosive and heat resistance , Gives better life span , about 10 years.
11) Method of construction - Water cooled Cooler can be constructed through Stationary casing and rotating Screw or Vic versa is Rotating casing with stationary in built screw with housing
12) Heat transfer Area / contacts - Due to circular / U trough Casing and rotating Screw hollow water filled Screw flights , the each and every particle has chance to come in contact with Surface for heat Extraction , thus the % of particles getting cooled is High and heat transfer is High. Finally about all ash gets cooled and does not left Hot / unearthed portions
13) Pollution Concerns - Water cooled cooler are Dust tight , totally enclosed and very rear chances to come the dust form any other areas excluding Inlet Section and outlet Sections. Thus environmentally very useful .The Noise level is very Low , noise level Operation is possible.
14) Power Consumption - Power consumption is almost same in average with Single Electrical Motor.
EQUIPMENTS INCLUSION DETAILS-
Powercon Equipments – Bed Ash Cooling System Comprises following Equipment’s-
ACTAUL SITE INSTALLATION PHOTO
WORKING STAGES –
1) The RED HOT about. 950 Deg. C material is being allowed to flow towards discharge through suitable slide gate opening towards the SURGE hopper Assembly. Approximate capacity of SURGE hooper is about 1or 2 minutes storage with respective to desired Capacity.
2) The stored material in Surge Hopper is being getting discharge by Slide gate / Rotary feeder with controlled cycles opening towards BED ASH COOLER inlet .
3) Suitable Metallic Rubber bound Expansion Joints are provided in between the BAC and Boiler outlets to accommodate vertical expansion effect in the assemblies .
4) The material get entered in BAC and due to continuous new surface in contact with HOT Bed Ash , Heat get extracted through out Bed material , resulting in cooling down the temperature of. The BED ASH.
5) The time required in cooling the BED ASH up to desired temperature at outlet of BAC is being calculated and BAC Speed is designed accordingly .
6) In case of BAC assembly having short length due to site constraint in inlet to outlet , the bed Ash is being get forward and reverse by rotating the screw in reverse and forward motion , This motion is designed with minutes detail and make sure of new fresh LOT of bed ash comes in BAC while OLD LOT of Bed Ash getting. Discharged. , Specifically care has been taken to maintain the desired capacity discharged throughout cycles .
7) Thus we get RED hot Bed Ash Temperature form 950 Degree C to. About. 150 Degree C at outlet of BAC , The further BAC discharge is being get discharge in common Cross Collecting DCF to take the material towards ELEVTED DCF and further to Storage SILO.
8) The inlet temperature of Bed Ash at inlet of cross collecting DCF is about 150 Degree C and same is being. Reduced up to about 75 Degree C . The Cross colleting DCF is. Also having water Jacket Assemblies throughout travel. I.e. Inlet to outlet areas .
9) The 75 Degrees C Bed Ash material further enters in Elevated DCF , to take towards Storage Silo ,The 75Degree C temperature is further get down up to ambient / below ambient while. It enters in Storage SILO. The Elevated DCF is also being constructed with water Jacket Assemblies.
10) The Storage SILO is so designed to accommodate about one Shift Bed ash material ,
11) The Storage Silo is being designed with auto infra-red sensors to control the LOW/ MEDUIM and HIGH levels of bed Ash in SILO.
12) Thus depend upon the level sensors indication the draining cycles of Bed Ash is controlled. Through PLC logic , That allows system to RUN /STOP up tp safer level indication of Bed Ash in Storage SILO.
13) The Storage SILO is being also taken care by introducing the DES ( Dust Extraction System) to avoid Dusty atmosphere inside the SILO or outside while Discharging the Bed Ash. The DES recycles the collected powder form bed ash again in main stream i.e. Storage SILO.
14) The Storage SILO is. Also being designed and manufactured by providing Vibration Pads / Pneumatic air pulsing System to get the free discharge of bed Ash towards disposal vehicles , The Vibration System does not allow to stagnate the bed Ash in Storage SILO.
15) The Stored bed Ash is being gradually discharged in Dust Conditioner assembly to get discharged in disposal vehicles . The Dust Conditioner assembly is water sprinkling mechanism to add the moisture id. Dry – Powder from Bed Ash. Thus adding moisture / Water inndrg bed Ash , the bed Ash does not get spillages in atmospheres and thus we reduce the pollution .
16) The isolation get / Live bottom Scree / Rotary feeder is. Being provided in between SILO Discharge Outlet and Dust Conditioner Inlet Section.
Thus the 950 Degree C Bed Ash material gets cooled up to or below ambient and safe disposal to RED HOT Bed Ash is. Being complete.
There are many instruments are being installed in System , like water flow detector , Water temperature detector , Bed Ash Inlet temperature and. Discharge out let temperature , level sensors ,motion detectors etc , This all system is. Being controlled through PLC base LOGIC and mimicry panel.
