Pulpers

Pulpers are devices or machines that transform solid materials into a pulpy mass, typically through mechanical disruption, enzymatic action, or chemical treatment. They are used in various industries to produce pulp for paper, purée, juice, or other processed products, and can refer to the equipment itself or, less commonly, to workers who perform pulping tasks.

In papermaking, pulping is the initial step that liberates cellulose fibers from raw materials such as wood chips. Pulping methods are chemical (kraft or sulfite processes) or mechanical (groundwood, refiner mechanical, or stone pulping). Chemical pulping uses reagents in digesters to separate fibers by breaking down lignin, yielding strong, long fibers; mechanical pulping relies on grinding to separate fibers with higher yields but shorter lengths and higher energy use. Pulpers are part of the production line alongside digesters, refiners, and screens. The resulting pulp is washed, refined, and often bleached before being formed into sheets.

In food processing, fruit and vegetable pulpers crush or macerate produce to produce pulp, purée, or juice. They may be single- or multi-roll devices with rotating rollers, shredders, or high-shear blades, sometimes equipped with screens or de-seeding mechanisms. Pulpers are used for apples, tomatoes, berries, and other fruits, frequently as a step before pressing, canning, or further processing.

Industrial pulpers also appear in paper recycling to disintegrate waste paper into fiber slurries, enabling contaminant removal and deinking. They are designed for different fiber types, moisture levels, and throughputs.

Key considerations include pulp quality and fiber length, energy consumption, throughput, and chemical usage for chemical pulps, as well as sanitation and food safety for edible pulps.