The actual capacity of a horizontal fertilizer mixer(ribbon mixer) is not a fixed value; factors such as material type, moisture content, specific gravity, fiber content, and the degree of agglomeration directly alter the mixing time per batch and the loading volume, ultimately significantly affecting hourly and daily output.

When mixing dry, single-nutrient fertilizers (such as urea, monoammonium phosphate, and potassium chloride), the particles are uniform, flow well, and are non-sticky, allowing the loading factor to reach approximately 70% of the tank volume. The materials tumble rapidly with minimal stratification, achieving a homogeneous mix in just 30 to 60 seconds and discharging smoothly without residue. Under these conditions—with the fertilizer produciton machine running continuously at full load—the rated output can be achieved, representing the scenario with the highest mixing efficiency and most stable capacity.

When mixing composted organic fertilizer or organic powders—which contain 25%–35% moisture and coarse straw fibers—the material is highly viscous and prone to clumping and sticking to the tank walls. Consequently, the loading factor must be kept below 50%; overloading causes a sharp spike in mixing resistance and motor overload. Breaking up clumps requires a longer mixing time (1.5 to 3 minutes per batch), and significant material residue on the walls necessitates extra time for cleaning; thus, the actual output for the same machine model is only about half that of mixing chemical fertilizers. If the material is severely agglomerated, mixing time must be extended further, causing capacity to drop even more.

When mixing organic-inorganic compound materials, the mixture contains a blend of dry and wet particles with significant differences in specific gravity—heavy chemical fertilizer granules sink while light organic powders float on top. To prevent stratification in the finished product, the mixing time falls between that of pure chemical fertilizer and pure organic fertilizer, with a loading factor of approximately 60% and an actual capacity about 30% lower than that of pure chemical fertilizer. If additives like bentonite or fine humic acid powder are included, the generation of dust and moisture absorption exacerbate wall-sticking issues, leading to a slight further decline in capacity. Materials containing significant amounts of gravel or hard lumps increase the operating resistance of the ribbon agitator; consequently, the equipment must run at reduced speeds to protect the blades, and cleaning frequency must be increased, resulting in shorter effective production time and lower output. In summary, for the same horizontal mixer, production capacity is highest when processing dry chemical fertilizers, lowest for pure wet organic fertilizers, and intermediate for organic-inorganic blends. When selecting equipment and calculating capacity, the actual primary production material must serve as the basis for calculation to avoid under-specifying the production line due to reliance on nominal parameters.