RU2293934C2 - Method for producing of double-layer ice - Google Patents

Abstract

FIELD: production of double-layer ice.

SUBSTANCE: method involves producing lower layer followed by producing of soft upper layer, with upper layer being provided by freezing-on of poured water containing ammonia additive in an amount of from 1 ppm to 100 ppm.

EFFECT: provision for obtaining of skating rink and other ice constructions with high-speed properties.

5 cl

Description

The invention relates to the creation of artificial ice and can be used in sports and construction to create artificial ice rinks, skating tracks, etc.

A known method of producing artificial ice, which includes the preparation of an aqueous polymer solution of polyvinyl alcohol and freezing, the solution contains polyvinyl alcohol at a concentration of 0.5-7.0 wt.%, And the solution is frozen at a temperature of from -10 to -60 ° C, and the resulting ice is kept at a temperature of from -2.5 to -6.5 ° C for 5-7 days. (Copyright certificate No. 1649218, F 25 C 1/00, 05.15.91).

The disadvantage of this method of producing artificial ice is that these impurities introduced into the ice mass, reduce its hardness, and as they are displaced to the surface, reduce its speed properties.

This drawback was partially eliminated when receiving two-layer ice (Goncharova G.Yu. et al. Secrets of the ice palace. // Refrigeration. - No. 5 - 2005. - p.10-13), one layer of which (lower) has increased hardness for prevent deep penetration of the ridge blade into ice, and impurities were introduced into the other (upper) soft layer. As impurities, film-forming amines, plant-based composites, and water-alcohol solutions were used.

The ice obtained in this way, however, has a sufficiently high skid resistance and, accordingly, low speed properties.

The objective of the present invention is to develop and create a method of producing ice for artificial ice rinks, skating tracks and other ice structures with high speed properties.

The technical result of the invention is to increase the slipperiness of the ice, i.e. improving the sliding conditions on the surface of the ice by reducing the force of resistance to sliding of the ridge on ice.

The technical result is achieved by the fact that the claimed method of producing two-layer ice, including obtaining the lower layer and the subsequent obtaining of a soft upper layer, is also characterized in that the upper layer is obtained by freezing by pouring water containing ammonia in an amount of from 1 ppm to 100 ppm.

In addition, the upper soft layer is frozen with a thickness of not more than 1 mm.

In addition, the freezing of the upper soft layer of ice is carried out using ice machines.

In addition, the water used to make ice is subjected to preliminary treatment and deep deaeration.

In addition, water with a temperature of at least 60 ° C is used to freeze the upper layer.

The choice as an additive of ammonia in the declared amounts is due to the following.

In the course of research, the inventors found that the addition of ammonia to the upper layer of ice provides a stable increase in the sliding properties of the ice surface. So the introduction of such an additive to obtain the upper soft layer of ice frosted on the lower hard layer of ice creates the conditions for producing ice suitable for sports competitions in ice sports - speed skating, short track, figure skating, ice hockey and etc.

The inventors found that the use of ammonia in an amount of less than 1 ppm does not give the desired effect of the appearance of "softness" of ice, and in an amount of more than 100 ppm it leads to more than softened ice and penetration of ammonia into the lower hard layer, as a result of which the lower layer loses its hardness.

It should be noted that the use of ammonia in the declared amounts, while providing a positive effect on the quality of ice, nevertheless, is in very low concentrations - microconcentrations, which are not noticeable by the organoleptic of a person and do not affect his health.

The choice of the thickness of the soft top layer of not more than 1 mm is due to the fact that with a larger thickness of the layer when the ridge moves, it deepens into this ice layer, which leads to an increase in the sliding resistance force.

Preliminary treatment and deep deaeration of water is an additional condition for obtaining a smooth, defect-free, without the inclusion of air bubbles of ice.

Another condition is compliance with the temperature regime for water when freezing the top layer: when pouring into the tank an ice picking (filling) machine, water is used with a temperature of at least 60 ° C, which is important to reduce the rate of ice crystallization.

Example 1 implementation of the claimed method.

Initially, freezing of the lower layer of ice was carried out. The water used for this stage of pouring passed the purification system by passing it through a mass filter and activated carbon, and also underwent deep deaeration.

In the frozen lower layer of ice, temperature stresses were relieved by annealing and subsequent ice compaction.

A surface soft layer with a thickness of up to 1 mm was obtained by crystallization of a layer of water deposited on the planed surface of the lower main massif of hard ice when passing an ice-picking (filling) machine. Pretreatment of water included the following main stages:

- purification from mechanical impurities (filtering);

- clarification and removal of active chlorine using activated carbon;

- softening (removal of hardness salts on the ion exchanger);

- desalination up to 98-99% (reverse osmosis);

- removal of dissolved gases by vacuum and thermal deaeration;

- UV disinfection.

After cleaning, before the introduction of the additive, the water had a specific conductivity of 5-7 μS / cm ^-1 , pH up to 7.8, the dissolved oxygen content up to 1 mg / L.

When pouring an ice picking machine into the tank, water was used at a temperature of 60 ° C.

To freeze the upper soft layer, 1 ppm ammonia additive was added to water. The path length of a slide meter - a device that measures the slippery of ice (described in the article by G. Goncharova, SI Nefedkina, Secrets of the ice palace or the chronicle of the first victories on Krylatsky’s ice. - Refrigeration equipment, 2005, No. 6, p.6- 8), averaged 20.5 m.

Example 2 implementation of the claimed method.

All conditions for producing two-layer ice remained the same as in Example 1, except that 100 ppm of ammonia was added to freeze the upper soft layer in water. 65 ° C water was poured into the tank of an ice picking (filling) machine.

The mean free path in this case was 23 m.

Example 3 (comparative) ice production by the prototype method.

All ice conditions remained the same as in Example 1, except that a plant-based composite additive was added to freeze the upper soft layer in water. The path length of the slide meter in this case averaged no more than 19 m.

The above examples clearly confirm that when implementing the inventive method, it is possible to obtain the above technical result.

Claims (5)

1. A method of producing two-layer ice, including obtaining a lower layer and subsequent obtaining a soft upper layer, characterized in that the upper layer is obtained by freezing by pouring water containing an ammonia additive in an amount of from 1 to 100 ppm. 2. The method according to claim 1, characterized in that the upper soft layer is frozen with a thickness of not more than 1 mm. 3. The method according to claim 1, characterized in that the freezing of the upper soft layer of ice is carried out using ice machines. 4. The method according to claim 1, characterized in that the water used to produce ice is subjected to preliminary treatment and deep deaeration. 5. The method according to claim 1, characterized in that for freezing the upper layer of ice using water with a temperature of at least 60 ° C.