JPS63500526A - How to make artificial snow - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] How to make artificial snow Seikōro Seibunritsu The present invention relates to a method for producing artificial snow and to a ski resort using such snow.

Apical calculus limb blood goju skin At several ski resorts around the world, people ski resorts use a variety of different techniques. To be carried out.

One method is to add atomized water and compressed air (or other gas) to the subfreezing atmosphere. is to form artificial snow using machines that spray and form snow blankets . Adiabatic expansion of air absorbs heat from atomized water, and the particles form snow flakes Freeze like that. This machine is expensive to install and operate, and requires large amounts of compressed air. In order to prevent snow from melting, air and ground temperatures must be below 0°C. skiable snow can only be produced when heavy investment and operation Despite the cost, such machines are available as ski resorts at certain resorts. Such machines are currently in use because the period can be extended by one month. .

The basic method for producing snow using this type of technology is described in U.S. Pat. No. 676.471 (Pierce). Improvement methods and equipment for this technology The location is US Patent 11m 3,716.190 (Lfndlof); 3.0 10.660 (Barnett); 3.301,485 (Tropean o); 3.298,612 (Torrens); 3.761.020 (Tropeno et al);3+774J43 (Rice):3 ．． 774.842 (Howell); 3.945.567 (Rambach ); 4,004.732 (flanson); 4.083,492 C Dewey) ;4.105.161 (Kircher et al) ;3,733.02 (Eustis et at) + and Australian special Permission 1fiTh 77956/75 (gurnss) and 12534/83 (Albertson).

The atomized water particles are fed into an air stream generated by a fan (e.g. U.S. Patent N113.760,598 (Jakob et al.) and 2° 968.164 (as shown in Ranson), and snow flakes Or the formation of crystals is ice crystals (U.S. Patent +th 3,596.476 (Jako b et al)) and bacteria (see U.S. Patent TLH 4,200, 228 (see Woerpel)). promoted.

To prevent artificial snow from melting, US patent m3,893,507 (Mac -Cracken et al) and Australian Patent Na 363.9 62 (Michaelis) for ice rinks and in mining. Those who freeze or cool the earth using the type of refrigeration system used Disclose the law. These methods do not overcome the problem of snow flakes melting in the air and For example, steady-state freezing of snow generated by the Pierce method involves freezing the snow from the air above the snow. When heat is absorbed through the snow into the ice, it eventually turns into an ice porridge that is unsuitable for skiing. Will.

In warmer regions, ski slopes may be made of synthetic mats, bristles or covers. - Developed using pets. Such slopes are “Dendex”, “D sold under the trademarks ``elta'' and ``Dri-3no'' and has a U.S. patent. PlkL3,400.643 (Holley), 3,731.923 ( Grieve) and Australian patent application Nu 71499/74 (Sn ow Products Inc.). These slopes are Requires separate skis and balls and forms a truly snow-covered slope I can't speak.

An object of the present invention is to provide a relatively simple and inexpensive method of manufacturing artificial snow. Ru.

Preferred objects of the present invention, hitherto not considered possible, are further preferred. The purpose is to create snow with different crystal dimensions to reproduce, for example, powdery and tightly packed snow. The object of the present invention is to provide a method that can be used to lay down layers.

A further preferred objective is that the snow can be collected, reused, or reprocessed as needed. The purpose is to provide a method.

A further preferred object is to provide a ski resort containing snow produced by the method of the invention. It is about creating.

Other preferred objects will become apparent from the description below.

- In this aspect, the present invention includes: (a) mixing water and a water-swellable material below the maximum water holding capacity of the material; mountain) aerate the mixture, (e) A method for producing artificial snow, including the step of freezing the mixture to form snowflakes. exists in

Preferably, the water-swellable material swells with strong gel strength in an aqueous solution. This includes all polymers, copolymers and terpolymers that can These are acrylamide, acrylic acid, polyacrylate, vinyloxazolidino salts of methacrylates, styrene, vinyl ethers and styrene sulfonic acids polymers and copolymers of cellulose fibers and polymers and copolymers of cellulose fibers. Contains mar. Suitable polymers are described in U.S. Pat. No. 3,247,171 (Wal ker et al); 3.022,279 (Proffitt): 3.022.280 (Shukys).

3.251.194 i British Patent No. 111NI 211271005 (Che a+1cal Discoveries As) and Australian Patent N a 464+077 (The Dow Chemical Company) It is described in.

The polymer is used to provide good gel strength, minimal evaporation and reduced permeability. Most preferably, it absorbs about 30 to 100 times its own weight in water.

Preferably, the water-swellable polymer for hard snow has a maximum water holding capacity of 30 to Mixed with water at 85%, more preferably 50-70%. For example, this is water 50 Part: The property may be 1 part (by weight) of polymer. Preferably for fine powder snow, The polymer has an odor content of 5-50%, more preferably 5-15% of its maximum water holding capacity. and mixed with water. Such a mixture contains 5 to 15 parts water: 1 part polymer (by weight). You can

Snowflake matrix to reduce the surface tension of water and generate a honeycomb effect Surfactants can be added to the mixture to generate microbubbles within the bath.

Suitable surfactants include soaps and detergents, linear or branched alkylbenzene sulfonants. nates, sulfated aliphatic or aromatic alcohols, alkylarene sulfonates, Sodium Dodecylbenzenesulfonate, Alkyl Sulfonate, and Anion Cationic or anionic surfactants, including surfactants, cationic and nonionic surfactants. When using sex agents, the polymer becomes cationic or anionic and forms a snowflake. become mutually exclusive.

The mixture can be applied either by spraying from a nozzle or mechanically in a mixing chamber. Aeration can be achieved by stirring or whisking.

The mixture can be frozen at 0°C or below, and the hardness of the ice varies within each crystal. increases as the temperature decreases as additional water is frozen. (contained within the polymer) It was observed that crystals were formed when about 5% of the water contained in the water was converted to ice. ) practical The lowest temperature is about -20°C.

The lightning strikes 75-200m, more preferably, forming a ski slope on the frozen floor. Preferably, it is laid at a depth of 125 to 150 m. Preferably, the snow is similar to natural snow. It is laid out in several layers. The frozen floor is similar to the type used for ice skating rink floors. (A suitable example is the Australian patent! lh 363.962 (M ichaelis) ; U.S. Patent N13°893.507: 3,379, 031: 2,878.651 and 3,751.935, and Holssten Ice Rinks Inc., Saint Ball, Minnesota, United States .

It is described in ``Ho1m5ten Rinkmaster'' sold by ``Ho1m5ten Rinkmaster''.

The floor is preferably surrounded by side walls to control the potential for environmental contamination when the snow melts. .

The amount of refrigeration required to keep the snow frozen will depend on the environmental temperature; The layer is scraped off the slope, the crystals melt back into the gel, and the foreign material is refrozen. and removed by mouth before redistribution onto the slope.

In a second aspect, the present invention provides a ski resort including artificial snow made by the above method. Exists.

Figure j mu λNya 104 Tsui In order to enable a thorough understanding of the invention, reference may be made to the accompanying drawings showing preferred embodiments. An example will be described below.

FIG. 1 is a partially cross-sectional, partially schematic diagram of a ski resort.

FIG. 2 is a schematic layout of another snowflake manufacturing facility.

New Water-swellable polymers that are mixed with water and frozen to produce snowflakes are e.g. It can be formed from the components of

Water 100- Acrylamide monomer 20% Tetramethylethylenediamine 1 part 7% ammonium persulfate 4 pieces Methylenebisacrylamide (0,002~o, oos%) 0~4g detergent interface Activator 10-50 (optional) These ingredients are well mixed and can hold 50 to 100 times its own weight in water. React exothermically to produce a highly cross-linked polymer matrix capable of It is permissible to respond. The resulting gel is dried and ground into powder or is formed into flakes or granules.

The manufacturing of ski slopes using polyacrylamide powder will now be explained with reference to Figure 1. Describe it.

The ski slope 10 is attached to the slope of a mountain or hill to provide downhill skiing. It will be done.

The slope has a side wall 1 that controls the outflow of the water/polymer mixture when the snowflake melts. Surrounded by 1. This avoids possible damage to the surrounding environment.

A flexible refrigeration pipe 12 is laid in a sand bed 13 on an underground base 14. frozen The pipes are connected to respective manifolds 15 which are connected to freezing units 16. It will be done. The frozen liquid from the vibrator 12, for example brine, passes through the heat exchanger 17 and It is returned via line pump 18. Heat from the frozen liquid is transferred to the heat exchanger 17 and the cold It is vented by liquid circulating by pump 20 through freezing tower 19.

water from the supply tank 21 and polyacrylamide powder from the supply hopper 22. is supplied into the mixing chamber 23 in a ratio of 50 parts by weight of water: 1 part by weight of polymer, and The polymer is mixed so that it absorbs water to about 50% of its maximum water holding capacity.

The resulting gel passes through a line 24 into which air is injected by an air compressor 25. pumped through. From the air compressor, the aerated gel passes through line 26 exposed on the frozen floor 28 formed by the frozen pipe 12 and the sand bed 13. A manifold connected to a row of spaced nozzles that sprays aqueous gel. 27 through line 26.

Since the air above the floor is below 0°C, the polymer particles sprayed from the nozzle of water begins to freeze, and as soon as 5% of the water freezes, snowflakes are formed and this water becomes a polymer. A frozen shell forms around the remainder of the water absorbed into the mer particles. Polymer - is highly cross-linked, so the pores in the polymer particles are very small, and Due to the presence of ice, only a small amount of cross-linking occurs between the crystals, and the layer of lightning crystals is formed when lightning strikes about Lay it down to a thickness of about 25 tsuru at a time until it reaches a thickness of 125 to 15 on. these layers The snow in this area has the characteristics of natural, hard-packed snow.

A thin layer of fine powder snow, e.g. 6 to 120 mm thick, forms on the surface of the already laid snow. It will be done. The water-polymer ratio is reduced to water 5-b. Due to its high polymer content, snow is environmentally acts as an insulator against the absorption of heat from the air, and the C0-NH2 side chain is U Absorbs V-rays. If it rains, the polymer will protect the ski surface without damaging it. Can absorb some water.

The test is carried out in the freezing polymer by lowering the temperature to e.g. -20'C. The percentage of water absorbed in increases to e.g. 85%, and if the temperature e.g. If allowed to rise to -2℃, the ice in the frozen ice shell will be destroyed by snow crystals. It was shown that the gel could be melted without regenerating. However, as the temperature drops As it grows, the crystals become harder due to their high water content.

This phenomenon leads to significant savings in the operating costs of the refrigeration unit 16.

When the ambient air temperature is low at night, the refrigeration unit lowers the snow crystal temperature by -18℃, for example. High ambient air temperatures during the day can heat the crystals, but only However, as long as the snow temperature does not exceed -1.8℃, it will not affect the snow. If the ambient temperature is relatively high, e.g. 5 to 10°C, the refrigeration unit will It is only necessary to operate for a short time to maintain the temperature below the critical temperature of -1.8℃ (this critical temperature Temperatures will depend in part on the particular polymer used, e.g. plastic materials The material's insulating cover acts as a weather barrier to protect the skier ( and supported on the slope (to reduce heat absorption by the snow from the ambient air).

To preserve the ski surface, scrape away a thin layer and remove the sacrificial surface along the sides of slope 1o. can be put into the drain groove 29. The snow melts and flows through pipe 30. It is drawn into a filter unit 31 where foreign objects, such as dust, are removed. (High The highly cross-linked polymer particles have a small bore size, so foreign particles are The now clean gel is transferred to mixing chamber 2 for return to the slope. 3 and sprayed on top of the existing snow in a fine powder layer. (Water required /polymer ratio, it would be necessary to maintain the section down the slope and By laying frozen pipes 12, the length and width of the slope can be changed throughout the year. 0 For example, when summer turns to autumn and the ambient air temperature drops, Additional sections of the rope can be provided with artificial snow until winter, and the slope is For example, the length can be 400 to 500 m. Spring brings warmer environmental temperatures , when natural snowfall decreases, additional artificial snow is applied to keep the slope at its maximum length. and can extend the normal ski season by, say, 30 days. As spring turns to summer, sections of the slope can be closed.

To save costs, melted snow is drained and the gel is stored for next season. can be done. (If preferred, dry the polymer and store it in powder form) be able to. ) In a modified embodiment of the invention (see Figure 2), water and The remer is mixed in the mixing chamber 23 as previously described, but with aeration. The gel is flash frozen in freezing unit 34 using liquid nitrogen. snow obtained The crystals can then spread out onto the slope 10 to form a layer to the desired depth.

It will be readily apparent to those skilled in the art that the specific examples described are only illustrative examples. In particular, by varying the water-to-polymer ratio within the stated range, and freezing snow By changing the temperature at which the snow crystals are formed, the characteristics of the snow crystals can be changed. This characteristic is It also depends on the degree of crosslinking of the polymer, crystal size and the particular polymer used. Dew.

Various changes and modifications may be made to the specific examples described without departing from the scope of the claims. can be added.

international search report

Claims (18)

[Claims] 1. (3) Mixing water and water-swellable material below the maximum water holding capacity of the material. process, (b) aerating the mixture; (c) a step of freezing the mixture to form snowflakes. Production method. 2. Water-swellable materials are polymers that can swell with high gel strength in aqueous solutions. -, copolymer or terpolymer. 3. The water-swellable material absorbs about 10 to 100 times its own weight in water. . 4. Water-swellable materials include acrylamide, acrylic acid, polyacrylate, vinyl Oxazolidinones, methacrylates, styrene, vinyl ethers and styrene The method of clause 2, comprising polymers and copolymers of sulfonate salts. 5. The method of clause 4, wherein the polymers and copolymers are copolymerized with cellulose fibers. 6. Due to hard snow, water-swellable materials retain water at 30-85% of their maximum water-holding capacity. The method of Clause 1, which is mixed with 7. Water-swellable materials have a maximum water-holding capacity of 50-70% when mixed with water. Method of Section 6. 8. Due to the fine snow powder, the water-swellable material is at 5-50% of its maximum water-holding capacity. The method of paragraph 1, which is mixed with water. 9. Water-swellable materials are mixed with water at 5-15% of their maximum water-holding capacity. Section method. 10. Water-swellable materials absorb 100 times their own weight in water and Therefore, water and water-swellable material are mixed in a ratio of 50 parts water to 1 part water-swellable material by weight. The method of Section 2. 11. Water-swellable materials absorb 100 times their own weight in water and For powder snow, the ratio of water and water-swellable material is 5 to 15 parts water to 1 part water-swellable material by weight. The method of the second term, which is mixed with. 12. The mixture is aerated with mechanical agitation or compressed air or gas. Method of Section 1. 13. The method of paragraph 1, wherein the mixture is frozen at a temperature range of -20°C to 0°C. . 14. At least the amount of water absorbed in polymers, copolymers and terpolymers Snow crystals are formed when 5% turns into ice, and there are only a few bridges between each crystal. The method of Section 4 or Section 5 that does not occur. 15. microscopically to reduce the surface tension of the water and create a honeycomb effect within the snowflake. The method of clause 1, wherein the surfactant is added to produce fine cells. 16. Surfactants include soaps, detergents, sulfated aliphatic or aromatic alcohols, Chain or branched alkylbenzene sulfonates, alkylene sulfonates , sodium dodecylbenzenesulfonate, alkylsulfonate, and anionic acid. 16. The method of claim 15, comprising onion, cationic, and nonionic surfactants. 17. Spray or spread snowflakes on the frozen floor to a depth of 75 to 200 mm. The method of paragraph 1. 18. Frozen floor and covering the floor by any of the methods described in paragraphs 1 to 17. A ski resort containing a layer of snow crystals created by snow.