Offcut reclaiming utilization technique for reclaiming paper production

Abstract

The invention relates to leftover reuse technique to reuse the leftovers from recycled writing paper making, including the following steps: compressing, exhausting, mixing, expanding and foaming, hot-press forming and cooling. The leftover reuse technique solves the problem that leftovers from recycled writing paper can not be used again in the prior art and adopts an ingenious method to avoid the difficulties in sorting the material, extruding and filtering out the impurities, drying, grinding and incising. The process is simple and practical and greatly reduces the production cost. The method reaches the effect of making the best use of the material and relieving the environmental pressure.

Description

technical field [0001] The invention relates to a process for recycling papermaking leftovers, in particular to a recycling process for recycled papermaking leftovers. Background technique [0002] The leftovers left after the production of recycled paper is a kind of industrial waste, its main components are plastic and fiber, and its composition is different from that of post-consumer domestic waste that is commonly seen in the market by compression molding and plastic packaging. (Paper and plastic exist in separate forms), such as juice, milk Tetra Pak, books and magazine covers, home appliances, food, gift plastic veneer packaging boxes, etc. [0003] The main component of the above-mentioned post-consumer domestic waste is finished paper, and the plastic components are few and of a single type, basically PE, PVC, PP plastic films, so it is easier to plasticize and cross-link again with common processes to become usable materials . There is a large amount of leftovers ...

AI Technical Summary

Problems solved by technology

[0006] 1. Difficulties in equipment: general plastic equipment is formulated for certain plastic properties, and it is difficult to deal with mixed plastics that contain many different processing properties;

[0007] 2. Difficulties in combination: It is well known that paper and plant fibers are hydrophilic, and plastic materials are lipophilic, and hydrophilic materials and lipophilic materials are difficult to match;

[0008] 3. Difficulties in drying: the water content of paper and plant fibers is basically soaked inside and outside, the water content of plastics is basically wet on the surface, and the water content of foamed plastics is related to the foam perforation rate. Only the surface is wet, some are only wet on the surface, and some are completely wet inside and outside

[0009] 4. The problem of crushing: Because some materials in the raw materials are tough and some materials are brittle, the ideal efficiency and quality cannot be achieved by single shear crushing and single extrusion crushing;

[0010] 5. The problem of magnetic separation: the labor intensity of manual magnetic separation is very high, and the magnetic separation of conveyor belt type magnetic separator is used. If the gap is small, the material will not pass through, and the efficiency is too low. If the gap is large, the iron will not be sucked out, not to mention iron nails and iron sheets. There are also non-ferrous metal hard objects such as aluminum cans and copper blocks that cannot be magnetically separated;

[0011] 6. Difficulties in extrusion: this kind of material is wet and loose, and it is quite difficult to feed, exhaust, knead, filter, etc. If the raw material is filtered by rubber and plastic extrusion, the large particles left behind the filter screen can be as high as 20% to 30%, the slag cleaning time will be longer than the normal working time;

[0012] 7. The problem of demoulding: it is impossible to use high-priced release agents and high-temperature-resistant isolation films for low-value-added products, and the sticking problem becomes an obstacle to molding;

If the nails on the board need to be cracked, the screws need to be drilled first, and the cutting efficiency is low, problems will arise. As a packaging material, its practical value will be greatly reduced;

[0014] 9. Difficulties in cutting: due to the miscellaneous ingredients and different sizes of leftover materials, among which there are many hard objects such as iron nails, iron blocks, stones, glass, and cans, it is easy to knock off the cutting blade

And because the cutting knife rotates at high speed, the local high temperature makes the plastic melt and stick to the knife, which greatly affects the cutting speed, and the rough cutting surface affects the appearance;

[0015] Due to the long-term inability to solve the above problems and the lack of low-cost treatment methods, due to the rapid development of the recycled paper industry in recent years, there are naturally more and more solid wastes, which has become a headache for the society and seriously affected the ecological environment. sustainable development of the industry