http://www.crytec.biz
Creators of Bubble Slurry Ice
FAQ
Header: FAQ

A) ABOUT ICE
  1. What is Slurry Ice?
  2. What is Solid or Flake Ice?
  3. How is Slurry Ice made?
  4. What are the main advantages of Slurry Ice compared to Solid or Flake Ice?
  5. Are there any advantages of crushed flake ice mixed with water or brine, also known as sludge, wet or liquid ice?
  6. Why do you need seawater or salted water to make Bubble Slurry™ Ice?
  7. What happens to the salt you need to make Bubble Slurry™ Ice?
  8. Since salt must be used to produce Bubble Slurry™ Ice, what can be the salt uptake?
  9. Can you use anything else than salt to make Bubble Slurry™ Ice?
  10. What is the cooling capacity of your Bubble Slurry™ Ice?
  11. Does your Bubble Slurry™ Ice melt faster than flake ice?
  12. Why do you add air or gas to make Bubble Slurry™ Ice?
  13. Why is it easy to pump Bubble Slurry™ Ice?
  14. Can you produce pure ice: Bubble Slurry™ Ice with a 100% ice concentration?
  15. How do you regulate the Bubble Slurry™ Ice concentration and temperature?
  16. When can you make Bubble Slurry™ Ice online (on demand), and when do you need a storage tank (also known as TESS or a Thermal Energy Storage System)?
  17. Can slaughterhouses make use of Bubble Slurry™ Ice?
  18. Can Bubble Slurry™ Ice be used in food production processes that require product chilling, like the production of sausage, cold cuts, cheese, bread, etc.?
  19. What is the benefit using Bubble Slurry™ Ice before freezing food, like vegetables, shellfish, etc.?
 

B). ABOUT ICE SYTEMS

  1. What is Refrigeration?
  2. How old is the Refrigeration Technology?
  3. How can Refrigeration affect the Environment?
  4. What are the advantages of using HFC’s (hydrofluorocarbons) over other refrigerants, like Ammonia,  Propylene or Ethylene Glycol, Synthetic or Paraffin Hydrocarbons, and Silicones?
  5. Are you using R-22 Freon® as a refrigerant?
  6. How much refrigerant do your Bubble Slurry™ Ice machines charge?
  7. Why do some ice machines consume more electricity than others?
  8. Why is there such a difference in performance (icemaking capacity) between ice machines?
  9. What are the advantages of your second generation versus the first generation slurry ice machines of other companies?
  10. What are the advantages of your Bubble Slurry™ Ice systems versus solid or flake ice makers?
  11. How much electricity do your Bubble Slurry™ Ice machines consume versus other ice machines?
  12. With which electrical safety standard (IP or Ingress Protection) do your Bubble Slurry™ Ice systems comply and which certifications do they have?
  13. Why are Bubble Slurry™ Ice machines so much smaller than other types of ice machines?
  14. How do you regulate the Bubble Slurry™ Ice concentration and temperature?
  15. Why is Bubble Slurry™ Ice stored “special” storage tank, and why does it have a “special” mixer?
 

 



ABOUT ICE

  1. What is Slurry Ice?
    Slurry Ice is a mix of ice crystals and a water solution, often seawater, salted or sweetened water. Slurry Ice is also known as liquid ice, slush ice, flow ice, fluid ice, or by a wide range of trade or brand names.


  2. What is Solid or Flake Ice?
    There are various forms and shapes of solid ice:
    1. Block ice (or cake ice) is made by freezing water in a mould to form a block typically weighing about 50 kg (110 lb), which is stored whole and normally has to be crushed before use to give small irregularly shaped pieces known as crushed ice.
    2. Flake ice (also known as scale or slice ice) is produced by freezing a thin layer of water on a refrigerated cylinder, and scraping it off in fragments or flakes. Flake ice crystals are usually not smaller than 1 mm (1000 µ or 0.04 in), and have sharp edges; when used in chilling or cooling of products, flake ice can damage the product, and also loses 20-50% of its cooling efficiency as cooling surface area is lost due to air pockets and irregular shapes.
    3. Tube ice (or pipe ice) is made by freezing water inside vertical tubes, cut into short lengths on release, and sometimes crushed before use.
    4. Small ice refers to the many kinds of ice made in small pieces in addition to those described above, such as snow or powder ice, plate ice, ribbon ice, cubic ice, and many others.


  3. How is Slurry Ice made?
    There are three ways to produce Slurry Ice, each with different characteristics and capabilities:
    1. Slurry ice can be made by crushing or grinding solid ice, and mixing the created sludge with salted or sweetened water. The resultant mix, however, still contains 500 to 15,000 µ (0.5 to 15 mm, or 0.02 to 0.6 in) large ice crystals with sharp edges.
      A lot of energy is needed to produce this kind of slurry ice:
      • first to make the pure ice cubes, produced at temperatures of -25°C to -35°C
        (-13°F to -31°F)         ;
      • then to crush or grind the solid ice;
      • finally to mix the ice with water, until it has become a sludge or “slurry”.
    2. Slurry ice can be produced using a tube-in-tube evaporator or crystallizer, based on a technology that is 25 years old:
      • salted or sweetened water is pumped into the inner tube;
      • a refrigerant is circulated between the inner and outer tube;
      • on the wall of the inner tube ice crystals are formed at temperatures that range from -15°C to -25°C (+5°F to -13°F);
      • the formed crystals are then cut from the wall by rotating knives;
      • a mix of water and ice is subsequently collected;
      • the slurry ice mix contains small 20 to 200 µ (0.02 to 0.2 mm, or 0.0008 to 0.008 in) small ice crystals.
    3. Bubble Slurry™ Ice, which contains ice crystals of 5 µ (0.005 mm, or 0.0002 in) in size and are formed at a moderaterefrigerant evaporating temperature of -12°C to -17°C (+10°F to +1°F), is produced by Crytec’s second generation tube-in-tube evaporator, in which ice crystals are formed inside the entire space of the inner tube. No knives or scrapers are required in which ice crystals are formed inside the entire space of the inner tube. No knives or scrapers are required. Click here for further details.


  4. What are the main advantages of Slurry Ice compared to Solid or Flake Ice?
    There are five main advantages:
    1. Slurry Ice can be pumped through regular hoses or pipes, so no more shoveling and hauling bins or tubs with ice cubes or flakes;
    2. Slurry Ice surrounds the to-be-cooled products completely, leaving no air pockets, and therefore capable to extract heat better, faster and more efficiently;
    3. Slurry Ice is soft and has no jagged or sharp edges, thus preventing injuries or damages to the product-to-be-cooled;
    4. Slurry Ice requires less energy, space, and money to produce;
    5. Because of its optimal cooling efficiency as a result of 100% use of its cooling surface area, a Slurry Ice mix requires less (usually 30-50% less) pure ice crystals than pure Flake Ice.


  5. Are there any advantages of crushed flake ice mixed with water or brine, also known as sludge, wet or liquid ice?
    There are no advantages, to the contrary. First of all, the energy needed to produce this type of ice is 2 to 3 times higher (see How is Slurry Ice made?). Secondly, because the temperature of the water or brine used to mix with the ice can be between 10°C and 30°C (50°F and 86°F), part of the produced ice, up to 35% of ice weight, will be lost. As a result, the final temperature of the water-ice mix can reach only 0°C to +2°C (32°F to 36°F). Lastly, the heat flux (i.e. cooling temperature rate) of this mixture will not be sufficient to cool the product-to-be-cooled rapidly and efficiently.


  6. Why do you need seawater or salted water to make Bubble Slurry™ Ice?
    One of the major benefits of using Slurry Ice is that it can be pumped through regular hoses or pipes.  In order to make it pumpable, the viscosity of the ice-water-air mix needs to be close to that of water or jelly, which can be achieved by adding salt or using seawater.

    The other reason for using salt is to lower the freezing temperature to well below 0°C (32°F), the temperature when water changes from liquid to solid, at which temperature the formed ice is hard and rough. The salt lowers the freezing temperature to around -1.8°C (+29°F) at which temperature smoother and smaller ice crystals can be formed.

    Finally, the added salt also decreases the adhesion forces of the cooling surface or wall of an evaporator. These forces cause the ice crystals to stick to the evaporator’s wall, and by diminishing these forces, the collection of the ice crystals is easier.

    Crytec recommends a salt concentration of at least 2.9% to produce its unique Bubble Slurry™ Ice. Note that other additives can also be used, like sugar, glycol, alcohol, fruit juice, etc.


  7. What happens to the salt you need to make Bubble Slurry™ Ice?
    Bubble Slurry™ Ice mix consists of ice crystals, water, and air or gas (CO2 or O3). At least 2.9% salt concentration is used to produce the Bubble Slurry™ Ice. Depending on the temperature and “age” of the Bubble Slurry™ Ice, at most 0.4% salt is detectable in the ice crystals self, whereas most salt remains in the water of the Bubble Slurry™ Ice mix.

    This phenomenon makes it possible to desalinate seawater with Bubble Slurry™ Ice: when the water is drained from the Bubble Slurry™ Ice mix, and the ice crystals are then melted, the result is pure, salt-free water.


  8. Since salt must be used to produce Bubble Slurry™ Ice, what can be the salt uptake?
    Marine or saltwater fish has a salt content that is equal to the salt concentration of the sea it swims in, ranging from 2.0% (close to the shore) to 3.5% (in the middle of the oceans). In freshwater fish the salt content is 0.2% to 0.8%, depending on the species.

    Salt has three benefits when catching or harvesting fish: it effectively controls protozoans (parasites) on the gills and skin, improves mucus production (shiny, healthy looking skin), and minimizes osmoregulatory stress during the catch or harvesting phase, thereby preventing stress-related effects, which consequently diminishes the quality of the fish.

    If Bubble Slurry™ Ice is used to chill-kill fish, no salt diffuses into the fish meat before or during rigor mortis. Depending on the species, rigor mortis sets in 3 to 8 hours after death, and resolves fully (post rigor mortis) 40 to 70 hours after death during storage at 0°C. Maximum muscle contraction occurs 18 to 30 hours after death. Only in the post-rigor mortis stage can fish meat absorb some salt. Tests have shown that the uptake can be about 0.2% to 0.5% in freshwater fish. The salt content in saltwater fish remains the same as the salt concentration of the Bubble Slurry™ Ice mix.
    See also  Can slaughterhouses make use of Bubble Slurry™ Ice?


     
  9. Can you use anything else than salt to make Bubble Slurry™ Ice?
    An additive that can lower the freezing temperature of water from the regular 0°C to - 2.9°C (+32°F to +27°F) is needed to create the Bubble Slurry™ Ice mix. Besides Salt, additives like Sugar, Alcohol, Fruit Concentrate or Juice, Propylene or Ethylene Glycol, Synthetic or Paraffin Hydrocarbons, Silicones, and more can be used. Each additive has its own properties and application in the process.


  10. What is the cooling capacity of your Bubble Slurry™ Ice?
    All ice is equal. The cooling capacity or refrigeration effect of ice is 80 kcal or 334.5 kJ per kg (144 Btu/lb). One kg (2.2 lb) of ice at -5°C (+23°F) has only about 3% more cooling power than 1 kg (2.2 lb) of ice at 0°C (32°F). The quantity of ice (P) required initially to cool a unit weight (G) of a product from a given temperature (t) to 0°C (32°F) is: t multiplied by the specific heat (C) of the product, multiplied by G, and divided by 80: (t.C.G)/80.

    Bubble Slurry™ Ice is used in varying concentrations, from 5% up to 50%, depending on:
    1. the initial temperature of the cooling medium, e.g. seawater,
    2. the initial and desired final temperature of the to-be-cooled product, and
    3. the amount (weight) of the to-be-cooled product.
    Because of its characteristics (typically the fact that 100% of its cooling surface is utilized due to its fluidity), the heat flux from Bubble Slurry™ Ice has a superior value, resulting in the fastest and most efficient cooling capacity.

    Note: “cooling medium” (e.g. seawater) is the liquid that will transform from liquid to solid state (ice); when that transformation is taking or has taken place, the medium is referred to as “cooled medium”. This should not be confused with “refrigerant”.

    In practice only a 1 : 1 ratio or {Bubble Slurry™ Ice mix with a 15% ice concentration} : {the product’s weight} is needed to cool (e.g. a sea bream of 0.5 kg or 1 lb) down from +16°C (61°F) to 0°C (32°F) within 15 minutes.


  11. Does your Bubble Slurry™ Ice melt faster than flake ice?
    First of all, the phenomenon “melting ice” means that the ice is extracting heat from its surroundings (a product to-be-cooled, ambient air, or water). Melting ice means that the ice is “working”, and this is what the ice is supposed to do.

    Secondly, seeing flake ice or ice chips on a product does not mean that the product it is cooling has reached the desired temperature. In fact it could mean the opposite, with ice crystals visible it could mean that the product has not been cooled down sufficiently, which is due to the fact that the heat transfer surface of flake ice is inadequate.

    Bubble Slurry™ Ice cools down a product faster and to a lower temperature (-1°C to +1°C or 30°F to 34°F) than any other type of ice ranging from +4°C to +12°C( or 25°F to 54°F). If Bubble Slurry™ Ice is used on products during refrigerated transport or in cold storage, the product remains at the ideal temperature and the Bubble Slurry™ Ice remains visible. If, however, the product has not been cooled sufficiently or if the ambient temperature is higher than 0°C to +1°C, then the Bubble Slurry™ Ice will start “working”, keeping the product’s temperature down, which is visible by seeing the Bubble Slurry™ Ice melt.

    The melting of ice fully depends on the circumstances during transport or storage.


  12. Why do you add air or gas to make Bubble Slurry™ Ice?
    Air or gas (CO2 or O3) is added in order to create turbulence inside the evaporator, thereby preventing the growth of ice crystals on the evaporator’s heat exchange surface. In addition, the air or gas bubbles themselves become centers of crystallization inside the cooling medium. Finally, as part of the Bubble Slurry™ Ice mix, the air or gas bubbles decrease the average viscosity, allowing Bubble Slurry™ Ice to be pumped through regular pipes or hoses.

    Carbon Dioxide (CO2) is added for the production of carbonated, frozen drinks.

    Ozone (O3), sometimes called "activated oxygen", is the second most powerful sterilant in the world and its function is to destroy bacteria, viruses and odors. Crytec is actively investigating the uses of Ozone in combination with its Bubble Slurry™ Ice.


  13. Why is it easy to pump Bubble Slurry™ Ice?
    The added air or gas (CO2 or O3) lowers the average viscosity of the Bubble Slurry™ Ice mix, allowing Bubble Slurry™ Ice to be pumped by conventional pumps through regular pipes or hoses over a distance of up to 100 meters.


  14. Can you produce pure ice: Bubble Slurry™ Ice with a 100% ice concentration?
    If “all” water is drained from a Bubble Slurry™ Ice mix, an ice concentration of 70% to 90% can be attained; because of its characteristics, not all water can be drained from the mix. Bubble Slurry™ Ice concentrations up to 50% can be pumped through regular pipes or hoses over a distance of up to 100 meters. Concentrations between 50% and 70% can also be pumped, but require powerful pumps and special coated piping. Ice crystal concentrations above 70% are not possible, since the Bubble Slurry™ Ice will maintain a 30% water content, even when all water seems (visually) to be drained from the Bubble Slurry™ Ice.

    Bubble Slurry™ Ice concentrations are determined by the flow rate of the cooling medium (e.g. seawater) in the Bubble Slurry™ Ice machine, and by adjusting the Bubble Slurry™ Ice  machine’s evaporating temperature (from -12ºC to -17ºC) and maximum condensing pressure of 20 bar for refrigerant R-507.
    Note: “cooling medium” (e.g. seawater) is the liquid that will transform from liquid to solid state (ice); when that transformation is taking or has taken place, the medium is referred to as “cooled medium”. This should not be confused with “refrigerant”.

    Click here to view the table and graph of Bubble Slurry™ Ice concentrations and temperatures.


  15. How do you regulate the Bubble Slurry™ Ice concentration and temperature?
    The concentration of Bubble Slurry™ Ice crystals as well as the temperature of the Bubble Slurry™ Ice  mix are regulated by adjusting the flow (L/min or gal/min) of the cooling medium (e.g. the seawater). Click here to view the table and graph of Bubble Slurry™ Ice concentrations and temperatures


  16. When can you make Bubble Slurry™ Ice online (on demand), and when do you need a storage tank (also known as TESS or a Thermal Energy Storage System)?
    As a result of the special design and construction of Crytec’s evaporators, Bubble Slurry™ Ice can be produced online (on demand) with a pure ice concentration of up to 30%, using cooling media (e.g. seawater) with an initial temperature of up to 25°C (77°F).

    TES should be used if and when the amount of product-to-be-cooled exceeds the online Bubble Slurry™ Ice production capacity (output per day, hour or minute). This can happen when the model Bubble Slurry™ Ice machine cannot produce the amount (kg or lb) and concentration (%) of Bubble Slurry™ Ice needed.

    There can be several possibilities why Bubble Slurry™ Ice cannot be produced online:
    • the Bubble Slurry™ Ice concentration (%) needed is higher than the ice machine’s online output, and/or
    • the Bubble Slurry™ Ice amount (kg or lb) needed is bigger than the ice machine’s online output, and/or
    • the initial temperature of the cooling liquid (e.g. seawater) is too high
    The solution is to produce Bubble Slurry™ Ice in a closed-circuit system and accumulate it in a storage tank. Crytec has designed special tank systems that function automatically in conjunction with its Bubble Slurry™ Ice machines to obtain and maintain a homogenous Bubble Slurry™ Ice mix at preset temperatures, concentrations and amounts.

    Click here for more, detailed information.


  17. Can slaughterhouses make use of Bubble Slurry™ Ice?
    Immediately after the slaughter, carcasses have to be cooled down rapidly to inhibit the growth of microorganisms, delay spoilage and prevent muscle shortening. This is mostly done in water-ice baths, spin chillers or dry-ice blasting chambers. In addition, many processors use salt water dips to treat meat against parasites and to give meat a shinier or fresher look. Both processes are meant to improve quality and extend shelf life.
    Bubble Slurry™ Ice can be used in these two processes combined: rapidly cooling the product and making use of the salt content of the Bubble Slurry™ Ice. Tests by Crytec (and several of its slurry icemaking competitors) have shown that the salt uptake by the meat, if the dip lasts shorter than 30-45 minutes, is negligble.


  18. Can Bubble Slurry™ Ice be used in food production processes that require product chilling, like the production of sausage, cold cuts, cheese, bread, etc.?
    Currently solid ice or chilled water is used in various food production processes where chilling is required after boiling or heating the product, such as sausages, hamburgers, cheese, or where high speed mixers cause excessive heating of the product, like mixing bread or pastry dough. The current chilling methods used are slow and inefficient. Bubble Slurry™ Ice is ideal for these applications.

    Click “Applications” for more information.


  19. What is the benefit using Bubble Slurry™ Ice before freezing food, like vegetables, shellfish, etc.?
    Prior to freezing vegetables or shellfish, the products are first boiled, and then need to be cooled down, maintain its water content, prevent “imprints” of solid ice, and subsequently complete a fast and efficient freezing process. Current solid ice or pre-chill methods are inefficient. Bubble Slurry™ Ice has proven to achieve all goals: maintaining water content, leaving no marks, and rapidly chill the product prior to freezing. Since most water is squeezed out of the Bubble Slurry™ Ice mix during the chilling process, salt uptake is minimal.

    Click “Applications” for more information.

 

ABOUT ICE MACHINES

  1. What is Refrigeration?
    Refrigeration is the achievement of temperatures below that of the local surroundings. The main purpose of refrigeration is thermal conditioning (e.g., for food preservation or air-conditioning), and the basic apparatus is a refrigerator, a thermal machine producing cold. Other names for special types of refrigerators are freezers, chillers, cryo-coolers, as well as the informal word fridge.


  2. How old is the Refrigeration Technology?
    Producing cold is basically different to and much more difficult than producing heat; people learnt to produce heat 500,000 years ago in the ice ages, whereas refrigeration started only 150 years ago in the 19th century. The first closed vapor compression refrigeration system with Ethylether as the refrigerant was patented in 1884. Later Ammonia was used, alongside Sulphur Dioxide and Methyl Chloride. Due to their flammability, toxicity or both, various secondary cooling brines were utilized as secondary refrigerants in indirect cooling processes. In 1921 R21 was launched; in 1930 the first chlorofluorocarbon (CFC) R12 started the beginning of the modern refrigerants. Since 1974, when CFC’s and other gases were said to harm the earth’s atmosphere (the Greenhouse Theory and the Ozone Depletion Theory), new refrigerants were introduced.


  3. How can Refrigeration affect the Environment?
    Ice machines make use of a refrigerant to rapidly cool down the cooling medium (e.g. seawater), which then transforms from a liquid state into a solid state (ice). HCFC’s (hydrochlorofluorocarbons), like R-22 or Freon© (a Dupont Corporation registered trade name), are still the most commonly used refrigerant in the refrigeration and air-conditioning industries worldwide. However, various international protocols and directives demand the phasing out of HCFC’s prior to 2010, because of their inherent Global Warming Potential (GWP). Already in some countries (like Sweden, Denmark, Norway and the Netherlands) new refrigeration equipment can no longer be charged R-22. All Crytec Bubble Slurry™ Ice machines are charged with an improved refrigerant, R-507, a HFC (hydrofluorocarbon).


  4. What are the advantages of using HFC’s (hydrofluorocarbons) over other refrigerants, like Ammonia,  Propylene or Ethylene Glycol, Synthetic or Paraffin Hydrocarbons, and Silicones?
    HCFC’s, HFC’s and Ammonia are the most commonly used refrigerants. Ammonia is mainly used in landbased refrigeration and icemaking systems, whereas HCFC’s and HFC’s are used on marine fishing boats as well in landbased systems.

    Ammonia is an effective refrigerant, but has become less valued due to its toxic and explosive characteristics. HCFC’s (like R-22 (Freon®) have become objectionable due to their negative impact on the atmospheric ozone layers; for instance R-22 Freon® is no longer permitted in new equipment in the EU and North America, and is being phased out in existing plants. The HFC’s have a far lesser ozone depletion effect.

    Propylene or Ethylene Glycol, Synthetic or Paraffin Hydrocarbons, and Silicones are used as secondary refrigerant or coolant. Their disadvantages are: lower heat transfer coefficient, higher energy consumption, and the need for larger (diameter and size of insulation) piping, increasing overall costs of installation and operation.


  5. Are you using R-22 Freon® as a refrigerant?
    Crytec does not use HCFC (hydrochlorofluorocarbon), like R-22 Freon®, as a refrigerant, but charges all its Bubble Slurry™ Ice machines with the HFC (hydrofluorocarbon) R-507, like Forane® or Klea®


  6. How much refrigerant do your Bubble Slurry™ Ice systems charge?
    Due to the superior heat transfer efficiency of Crytec’s ice machines between refrigerant and cooling medium, the refrigerant charge is only 1.4 to 4.4 kg/TR or 3 to 9.7 lb/TR compared to other ice machines: 3 to 10 kg/TR or 6.6 to 22.2 lb/TR (1 TR = 3.516 kW cooling capacity).

    TR or "tons of refrigeration" is a rate of cooling capacity, equivalent to the removal of heat at 200 Btu/min (200 kJ/min), 12,000 Btu/h (13 MJ/h), or 288,000 Btu/day (300 MJ/day). This unit of measure stems from the original use of ice for refrigeration. One pound of ice, in melting at 32°F (0°C), absorbs as latent heat approximately 144 Btu/lb (335 J/kg), and 1 ton (0.9 metric ton) of ice, in melting in 24 h, absorbs 288,000 Btu/day (300 MJ/day). In Europe the equivalent cooling unit is the frigorie or kilo-calorie (kCal), equivalent to 3.96 Btu. Thus 3,000 frigories/h is approximately 1 TR. A standard TR is one developed at standard rating conditions of -15°C (5°F) evaporating and 30°C (86°F) condensing temperatures, with -13°C (9°F) liquid subcooling and -13°C (9°F) suction superheat.


  7. Why do some ice machines consume more electricity than others?
    Making ice is in general an electricity consuming undertaking. Water needs to be brought down to low temperatures in order to change the liquid state of water into its solid state: ice.

    An ice machine needs several electricity-driven components in order to function:
    • A seawater or tap water delivery pumps
    • One or more compressors
    • One or more ice crystallizers (also named evaporator) with a motor to rotate either a drum assembly, or assemblies with scrapers, knives or other cutting devices, depending on the type of ice machine
    • One or more fans to enhance heat air-cooled condensers
    • A grinder or chopper to crush solid ice, if applicable
    • A mixer to blend crushed ice with a salt solution to produce an ice sludge, if applicable
    • A slurry ice mixer in storage/mixing tanks, if applicable
    • A slurry ice delivery pump or a solid ice conveyor belt, depending on the type of ice machine

    Most ice machine produce between 5 and 12.5 kg of pure ice per kWh (between 0.0003 and 0.008 lb per Btu). Crytec’s Bubble Slurry™ Ice machines Model CR-004 produces 18.5kg of pure ice per kWh (0.012 lb per Btu), and Models CR-010 and CR-020 17 kg/kWh (0.011 lb/Btu). Note that these figures include ALL electrical components necessary to produce Bubble Slurry™ Ice, such as refrigerant compressor, air compressor, process pump, 1-4 evaporator wiper motors and the electrical/electronic components.


  8. Why is there such a difference in performance (icemaking capacity) between ice machines?
    Not all evaporators (or crystallizers) give the same result (icemaking capacity). The main obstacle is called “Heat Impedance” (HI), which means “impeding the transfer of heat from one element or ingredient to another”. In the case of ice machines it means “from the (warmer) cooling liquid (like seawater) to the (colder) refrigerant”.

    In ice makers the factors that can negatively affect an adequate heat transfer are:
    • the HI between refrigerant and the evaporator’s wall,
    • the HI of the material of the evaporator’s wall,
    • the HI between the evaporator’s inner tube’s wall and the formed ice crystal layer,
    • the HI of the ice crystal layer itself,
    • the HI between the ice crystal layer and the cooled medium.
    The design of the first generation crystallizers creates a heat transfer coefficient from 700 to 1,400 W/(m2.°C) or 123 to 247 Btu/(h.ft2.°F), whilst Crytec’s second generation crystallizers realize a heat transfer coefficient of 2,000 to 3,000 W/(m2°C) or 352 to 528 Btu/(h.ft2.°F).

    Crytec’s Bubble Slurry™ Ice machines offer an optimum performance because their evaporators are:
    • made of a top-quality stainless steel alloy with extreme low heat impedance, offering an exceptional heat transfer coefficient;
    • precision tooled and polished, so that the inner wall has an optimal smoothness (low roughness), providing minimal adhesion forces on the evaporator’s inner wall, hence preventing the formation of ice crystals on the inner wall;
    • using Crytec’s proprietary, patented technology to produce its unique Bubble Slurry™ Ice: not on the wall of the evaporator’s inner tube, but inside the volume of the cooling medium, e.g., seawater.


  9. What are the advantages of your second generation versus the first generation slurry ice machines of other companies?
    Click here for a detailed explanation


  10. What are the advantages of your Bubble Slurry™ Ice machines versus solid or flake ice machines?

    They are:
    • smaller
    • lighter
    • simpler: fewer components
    • easier to deliver: pumpable through regular piping or tubing
    • less forceful: no need for powerful ice scrapers or knives
    • less expensive: no need for extremely low evaporating temperatures
    • more reliable: less maintenance due to fewer components and less powerful motors
    • more effective: higher heat transfer coefficient
    • more productive: higher specific icemaking capacity, expressed per m2 surface area of the evaporator: 450kg/(m2.h) or 90 lb/(ft2.h)
    • more efficient: 2 to 3 times less electrical energy consumption
    • more economic: less (30% to 50%) pure ice equivalent needed
    • complete: “plug & play” - all you need is water and electricity

    Comparisons are based on an equal/comparable net weight of pure ice.


  11. How much electricity do your Bubble Slurry™ Ice machines consume versus other ice machines?
    Between 54 and 60 kWh (depending on the model) per 1,000 kg (or between 24 and 27 kWh per 1,000 lb) pure ice equivalent, as opposed to 90 to 130 kWh* per 1,000 kg (or 40 to 60 kWh per 1,000 lb) pure ice equivalent.

    * Note: many manufacturers quote an electrical consumption of their ice machines without stating that additional components are needed to produce and deliver the ice, such as water or air-coolers, pump motors, air motors, electrical/electronic components and/or compressors.


  12. With which electrical safety standard (IP or Ingress Protection) do your Bubble Slurry™ Ice machines comply and which certifications do they have?
    Standard with IP 54, and by special order with IP 56.

    All ice machines carry the CE Mark; the American UL certification is under application.


  13. Why are Bubble Slurry™ Ice machines so much smaller than other types of ice machines?
    Crytec’s icemaking technology prevents the growth of the ice crystals on the evaporator’s cooling surface. As a result is the overall heat transfer coefficient twice as high than in other ice machines. Therefore require Crytec’s Bubble Slurry™ Ice machines smaller compressor-condenser units, smaller evaporators, and smaller motors to produce the comparable net weight of  pure ice.


  14. How do you regulate the Bubble Slurry™ Ice concentration and temperature?
    The concentration of Bubble Slurry™ Ice crystals as well as the temperature of the Bubble Slurry™ Ice mix are regulated by adjusting the flow (L/min or gal/min) of the cooling medium (e.g. the seawater).


  15. Why is Bubble Slurry™ Ice stored “special” storage tank, and why does it have a “special” mixer?
     Since Bubble Slurry™ Ice mix consists of ice crystals, water (H2O), and air or gas (CO2 or O3), homogeneity is required to maintain the right concentration in the whole volume of the storage tank. Therefore Crytec has designed special tank systems that function automatically in conjunction with its Bubble Slurry™ Ice machines to obtain and maintain a homogenous Bubble Slurry™ Ice mix at preset temperatures, concentrations and amounts.

    The special storage and mixing tank system consists of an insulated tank with a specially designed Bubble Slurry™ Ice-water separator and a mixing engine that rotates specially designed blades to ensure the homogeneity of the Bubble Slurry™ Ice mix. The fully automatic operation (water filling, Bubble Slurry™ Icemaking, mixing, pumping, and changes in ice fractions and temperatures) is controlled by a PLC (Programmable Logic Controller).

    If “all” water is drained from a Bubble Slurry™ Ice mix, an ice concentration of 70% to 90% can be attained; because of its characteristics, not all water can be drained from the mix. Bubble Slurry™ Ice concentrations up to 50% can be pumped through regular pipes or hoses over a distance of up to 100 meters. Concentrations between 50% and 70% can also be pumped, but require powerful pumps and special coated piping. Ice crystal concentrations above 70% are not possible, since the Bubble Slurry™ Ice will maintain a 30% water content, even when all water seems (visually) to be drained from the Bubble Slurry™ Ice.

    Bubble Slurry™ Ice concentrations are determined by the flow rate of the cooling medium (e.g. seawater) in the Bubble Slurry™ Ice machine, and by adjusting the Bubble Slurry™ Ice  machine’s evaporating temperature (from -12ºC to -17ºC or +10ºF to +1ºF) and maximum condensing pressure of 20 bar for refrigerant R-507.

    Click here for more, detailed information about Crytec’s “special storage and mixing tanks”
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