Start from the finished output you need per day. Then work back through shifts, effective running hours, yield losses and product mix to an hourly capacity for each section of the plant. Size each section for your hardest product, not your easiest.
Machine makers quote capacity in kilograms per hour. That figure is only useful once you know how many hours the plant will really run, and on which products.
Working out the numbers
- Forecast sales by product and pack size for the first few years, and include expected growth.
- Decide operating days per year and shifts per day, allowing for festivals, maintenance and seasonal breaks.
- Estimate effective hours per shift after start-up, cleaning, changeovers and breakdowns. Many plants run well below the clock hours.
- Allow for losses at cleaning, grinding and sifting, so raw material intake is higher than finished output.
- Calculate the required kilograms per hour for each section: cleaning, grinding, sifting, blending and packing.
- Add headroom for growth and for the hardest product in your range.
An illustration
Suppose you need 10 tonnes of finished powder a day. You run two 8-hour shifts, and expect about 12 effective hours. The grinding section then needs about 830 kilograms per hour of finished output.
If cleaning and grinding together lose a few per cent, the cleaning section must take in more than that. If fine turmeric grinds at half the rate of coarse chilli, and turmeric is a large share of sales, the grinder must be sized for turmeric. These figures are illustrative only. Your own losses and rates come from trials.
Bottlenecks and balance
Packing is often the real bottleneck. Many small pack sizes mean many changeovers and slower speeds. Size the packing section for your actual mix of packs, not for one large pack.
Buffer hoppers or silos between sections let each stage run at its own pace. They also let the grinder keep running while a packing machine is changed over.
Plan for product changeovers. Moving from red chilli to turmeric or coriander needs thorough cleaning to avoid colour and flavour carry-over. Some plants keep a dedicated line for chilli for this reason. If you also pack allergens such as mustard or sesame, ask your food safety adviser what separation and cleaning your market expects.
Raw material storage matters too. Many spices are harvested in a short season, so you may need to store several months of raw material in dry, pest-free conditions.
Space, utilities and people
Once you know the section capacities, the maker can size machines, motors and dust collection. That gives the power, air and floor space you need, as described in civil and utility requirements. For machine choices, see spice grinding plants and pulverisers.
Next step
We help you turn sales forecasts into a capacity brief, arrange grinding trials and compare makers against it. To start, book a free sourcing review.