1. Drying characteristics of materials. the drying curve, the critical moisture content, equilibrium moisture content.
2. Physicochemical properties of materials. morphology, water content, water properties, crystal water, particle size, density, viscosity, heat sensitivity, softening point, the phase transition point, thixotropy, toxic, corrosive, odor, flammability, easy explosive, static electricity, air permeability, agglomeration.
3. The value of the goods and the drying effect on materials. Such as product water, pollution, temperature, wear, powdered, crushed, rehydration and other factors impact the commodity value.
4. The requirements of drying production and long-term planning.
5. The technicals before and after the drying process.
6. The requirements for material recovery.
7. The available heat source (coal, oil, electricity, gas, liquefied petroleum gas, natural gas)
8. The drying methods used in the past or the drying method of similar products.
9. Environmental requirements - emissions of dust, noise, vibration, volatile and other restrictions.
10. Size of installation site, if there is special requirements.
11. The user's operator level and maintenance skills.
12. The purchase money, local prices of labor, land, energy.
13. The local average annual air temperature, humidity.