CS217900B1 - A method of treating conveyor belts for working below freezing temperatures - Google Patents

Abstract

The method consists of applying a protective layer of liquid carbohydrate hydrogenolysates to the moving belt, preferably in finely dispersed form, optionally heated to 100 °C, and then pouring powdered, granular or lumpy material intended for transport onto the belt thus treated. With conveyor belts thus treated, there is no compact freezing of the wet transported materials onto the belts.

Description

The invention relates to a method for treating conveyor belts for working at temperatures below freezing.

Operation of conveyor belts with moving belts during transport of wet materials such as coal, sand, ores, kaolin, etc. under freezing conditions is accompanied by failures, the most important of which is the destruction of belts caused by mechanical stress after freezing of hydrated materials on belts. At the bends, where the frozen layers break, the belt layers are disrupted or belt parts break off, moving parts (pulleys, rollers, pulleys, etc.) freeze and the conveyor is taken out of operation. Repairs are costly and time-consuming and downtime payments are often economically intolerable, especially where belt conveyors are integral parts of mining machinery, overhead excavators, excavators or power supply equipment, treatment plants and similar operations.

In accordance with the present invention, conveyor belts for working at sub-freezing temperatures are treated by applying a protective layer of liquid carbohydrate hydrogenolysates, preferably in finely divided form, optionally heated up to 100 ° C, onto the moving belt and thereafter sprinkles powdery, granular or lumpy material for transport.

The requisite hydrogenolysates can be obtained by known processes by treating carbohydrates, polysaccharides, starch or cellulose, as described in the literature. U.S. Pat.

642,462, U.S. Patent No. 3,341,609, U.S. Patent No. 3,396,199, and U.S. Patent No. 3,691,00.

The deposition of hydrogenolysates can be carried out by all conventional methods of applying paints - that is, by painting, pouring, sprinkling or spraying; even application in fine form (nozzles, atomizers and the like) is particularly preferred. In the case of the application of viscous hydrogenolysates, it is advantageous to heat them or to heat them. up to 100 ° C, which reduces viscosity and facilitates deposition. The conveyor belts can be modified either at selected time intervals or by continuous application; the choice of method can be influenced by weather conditions, the properties of the material to be conveyed, the wear rate of the protective layer and also by longer factors. By the method of the present invention, both surfaces of the conveyor belts - top and bottom - can also be treated, thereby preventing the material fallout from freezing onto the belt and, in addition, transferring deposited hydrogenolysates on the mobile part of the conveyor support device (pulleys, rollers and their accessories).

It can be concluded that the protective effect of the applied hydrogenolysate layer exploits the ability of the compounds contained to integrate into the ice crystal lattice due to the freezing of the moisture of the materials, which leads to cohesive degradation and reduced crust strength.

The consumption of hydrogenolysates during the operation of belt conveyors depends on the wear of the applied protective layer, on the moisture content of the transported material, or on weather conditions (snowfall, fog, rain, temperature) and is determined empirically. During repeated and continuous treatment of the strip, only the loss of hydrogenolysates, that is the amount that has adhered to the transported material, can be replenished. For example, in conventional coal transport by a belt conveyor, the consumption of hydrogenolysates is between about 0.1 to 0.25 l / m 2 of belt area.

The main advantage of operating belt conveyors with the belts treated according to the invention is that there is no compact non-freezing of the wet conveyed materials onto the belts, so that even frozen transported materials are easily separated from the belts without unduly disturbing them. This will reduce the breakdown of conveyors, reduce repair and downtime costs, increase throughput on the transport line, and generally increase the productivity of the entire production facilities. The hydrogenolysates used are non-toxic, practically non-corrosive to the elastic materials of the belts as well as its supporting device, consisting of metal, plastic, wood, etc. The carbohydrate hydrogenolysates are affordable because the raw materials for their preparation are sugars obtained from agricultural products such as beet, potatoes, grain, woody plants. To edit &

For example, the crude reaction mixtures resulting from hydrogenolysis can be used as a further economic advantage. Last but not least, hydrogenolyzates are used as a plasticizer in the treatment of the belts and, by penetrating into the upper layer of the belts, they favorably influence its elasticity.

Example

Sucrose hydrogenolysates heated to 45 [deg.] C. in an amount of 0.15 liters per square meter of belt area are uniformly sprayed onto the moving conveyor belt with a spray device positioned above the belt at a height of 40 cm. The grained or coated strip is applied to the treated strip. Lump substrate to be transported.

Claims (1)

Process for treating conveyor belts for working at temperatures below freezing, characterized in that a protective layer of liquid hydrogenolysates of carbohydrates, preferably in finely divided form, possibly heated up to 100 ° C, is applied to the moving belt and then a precoat is poured onto the treated belt. , granular or lump material intended for transport.