Fig 1 depicts schematic of a typical straight grate induration system The grate bars fixed on a moving strand are first covered with a layer of burnt pellet known as hearth layer The green pellets containing 7 to 9 wt % free moisture and 10 to 14 mm in size are then fed onto this layer and travel together with the sub layer through several thermal zones of the furnace
The second paper Iron Ore Pellet Dustiness Part II explains the relationship between AI and dust for good quality pellets; and compares fines generation between pellets fired in Straight Grate
Bentonite mixing devices tested at the LKAB straight grate plant at Malmberget Sweden reportedly have resulted in decreases in bentonite consumption In testing the pellet plant feed materials from each of the operations the first test series included firing of fresh plant green balls in the pot grate and batch rotary kiln in order to
In this work a mathematical model for the straight grate pellet induration furnace is presented The induration furnace is an equipment used for the efficient heat and mass transfer between the pellet bed and the flowing gas The model includes different physicochemical phenomenon like gas solid heat and mass transfer drying and condensation of free surface
Two types of systems are usually used for induration of the iron ore pellets a straight grate and b grate kiln process A hearth layer of fired pellets is used in the former to protect grate bars from excessive heating For any particular plant and pellet characteristics there are a set of optimal furnace operational conditions and
A full scale plant trial of the substitution of a specific organic binder for bentonite was conducted in the company s straight grate pellet plant in Quebec which produces Mtpa of pellets 36% of which are used as feedstock for the DR process The results of the full scale pellet plant trial are given in Table
Straight grate induration machine for 100% hematite Working area 189 m Construction of pelletizing plant with straight grate induration machine МОК 592М Working area 592 m Pallets х Reconstruction of straight grate induration machine Lurgi 278 B Working area 278 m Balling Disk ОЧ 7500
straight grate to restore the process performance and extend the lifetime of the entire grate system and components After decades of operation pallet cars display wear which and start to impact plant performance and energy consumption Maintenance needs compromise plant availability production and increases costs We offer the
Straight grate furnaces are widely used for induration of hematite pellets where typically 1% 2% carbon is added to the green mix to help in generating heat by combustion The quality of the pellets in such reactor varies from top to bottom of the bed as different layers of pellets are exposed to varying thermal and gaseous environments The thermal evolution as a
produced in a Grate Kiln system are uniformly high quality Hot pellets from the rotary kiln are discharged directly to the annular cooler where they are leveled to a uniform bed depth and conveyed over the primary and final cooling zones 46 Straight Grate pellet plants designed 46 Grate Kin systems with over 119 MTPA capacity installed worldwide
The company s pellet plant at Barbil has a total installed capacity of 9 MTPA production for different grades of pellets The plant is of dry grinding with recuperation type of straight grate technology The basic engineering of the plant has been designed by M/s Metso earlier known as Aker Kvaerner USA considering the input raw
TRAVELING GRATE DIMENSIONS 189 816 m² reaction area; or m machine width; CAPACITY million t/a in single unit; Specific production rates between 15 t per day and m² for limonite and 40 t for magnetite
A full scale plant trial of the substitution of a specific organic binder for bentonite was conducted in the company s straight grate pellet plant in Quebec which produces Mtpa of pellets 36% of which are used as feedstock for the DR process The results of the full scale pellet plant trial are given in Table
6 Mtpa straight grate pellet plant which is the first in the world to use dry grinding to achieve specific surface areas of 2600 3000 cm 2 /g Paul et al 2013 Closed
Straight grate furnaces are widely used for induration of hematite pellets where typically 1% 2% carbon is added to the green mix to help in generating heat by combustion The quality of the
pellets the straight grate SG and grate kiln GK induration processes Hatch has compared the merits of both technologies on a variety of aspects to better
Straight Grate Induration Furnace Samuel Nordgren ISSN 1402 1757 ISBN 978 91 7439 185 5 or green balls The green balls are then fed to one of the two pelletising plants MK3 or BUV where the pellets are upgraded to the final product of iron ore pellet The pelletising plants are divided into different zones drying zone pre heat
Fresh pellets are charged onto a hearth layer of the fired ones Hot gas is blown through the layer to dry out and fire the pellets at about 1300 °C In the grate kiln process the green pellets are charged onto the grate to form a bed of ∼180 mm depth In this process the bottom of the bed does not heat up so much to damage the grate bars
straight grate due to the absence of any tumbling action but straight grate pellets tend to be dustier than grate kiln pellets Another factor contributing to dust generation in the straight grate is the use of a hearth layer fraction which while being recycled tends to generate more dust BED HEIGHT AND PRESSURE DROP
