Process parameters are an important part of any quality control program. This is the process of measuring specific components of feed or ingredients at different stages like batching, grinding, mixing, conditioning, pelleting, cooling, crumbling, screening and packing.
In batching we have to take care that the initial moisture of the combine raw material batch should not exceed 12-12.5%;
In grinding we have to maintain the following parameters: (for poultry broiler pellets)
- Particle Size: More than 80 % of the average particle size should be below 1 mm.
- The gap between Hammer tip & Screen: As for fine grinding we need a lesser gap between hammer tip & screen and for coarse grinding, we need more gap between hammer tip & screen. There should be a gap adjustment feature in the hammer mill for different types of grinding texture required.
For all types of grinding solution Lark provides QGA “Quick Gap Adjustment”, as its name implies this technology is a boon for grinding different sizes of products as Fine /Medium / Coarse by the quick change of gap between hammer tip and screen.
In mixing we have to maintain the following parameters:
- The tip speed of hammer mill: Ideal Tip speed for a hammer mill should be 19000 -22000 FT/Min
- Specific energy of hammer mill: Average ideal power consumption of grinding unit should not be more than 9 units/ton.
- Temperature difference; Material in and out: Maximum difference in the grinding temperature (material in versus material out) should not be more than 5 degrees.
In Conditioning & Pelleting:
- The CV should be less than 5.
- Oil should be added after dry mixing (Medicine) of minimum 90 to 120 seconds.
- Minimum 60 seconds of retention time with adjustments to decrease or increase the retention time.
- Minimum 1.5 to 2.0 % moisture should be added through conditioners.
- Double shaft design for better mixing of steam.
- Multi-Point steam injections.
- Temperature range should be 75-85 degrees.
- Steam pressure at boiler should be 8.5-9.5 kg/cm2
- Steam pressure after PRV should be 2.0 to 2.5 kg/cm2.
- Steam should be Dry Saturated.
- PDI of Pellets should be more than 85%.
- Specific energy consumption of the pellet mill should not be more than 15 units/ton.
Crumbling & Screening
- Maximum variation in temperature after pellet cooler should not be more than + - 5 degrees of ambient temperature.
- The moisture of pellets aftercooler should be in between 11.0 to 11.5%
- Fines % in crumbling process should not be more than 25 %. (depend upon different formulation, particle size required and PDI)
- In any case, recycling in Finisher Pellet, Finisher Crumbs, Starter & Pre-Starter should not be more than 10%, 15%, 18%, and 25% respectively.
- Ideal moisture in finish feed should be in between 11.0 to 11.5. Too high moisture lowers the feed quality and leads to toxicity or fungus and too less moisture leads to process loss.
- Fines percentage (below 1 mm) in packing bags in Finisher pellet, Finisher crumbs, Starter, and pre-starter should not be more than 4 %, 7 %, 10%, and 12 % respectively.
The above information is based on data collected from our existing customers & internet sources and is only for your reference. As expertise in feed mill engineering only, Lark Engineering will not be responsible for any type of loss occur due to above stated information.