Soda Lime /CO2 Absorbent

Brandripo Sorb Name: Gripo Sorb
Gripo Laboratories has excelled in the field of manufacturing and developing CO2 Absorbent (Soda Lime) as per different standards. A unique CO2 Absorbent, Gripo Sorb has proved itself better than the classical and various other Co2 absorbents present in the market. This success has been achieved after extensive R&D and Market Analysis on Soda Lime for 20 years.

What is Gripo Sorb:
Gripo Sorb is a Soda Lime absorbent for removal of carbon dioxide and other acidic contaminants from gas streams. Gripo Sorb is an active compound formed by mixing calcium and sodium hydroxides. It is supplied as hard, porous, irregularly shaped granules that have been processed to maximize CO2 absorption and minimize dust formation.

Applications:

• Gripo Sorb is a carbon dioxide absorbent of choice for major hospitals across the world. It is used to absorb . Expired CO2 during anesthesia (in operation theatres).
  
• Also used in oxygen-based metabolism, in estimation respirators, breathing apparatus etc.
  
• Gripo Sorb is used for removing Carbon Dioxide from Diving Rebreathers.
  
• Gripo Sorb is a chemical technology for removal of Carbon Dioxide from manned enclosed atmospheres, such as submarine, and closed circuit breathing apparatus, such as rebreathers. It is used in navies by divers.
  
• The major applications of Soda Lime are in breathable gas applications where carbon dioxide levels need to be controlled, for example in medical anesthetic breathing circuits, in commercial and leisure diving rebreathers, or in submarines. In these applications, the breathable air is recirculated for re-use and therefore any exhaled carbon dioxide needs to be removed in order to prevent a build-up of carbon dioxide to toxic levels.

How does Gripo Sorb Work:
The Soda lime is contained in an absorber, appropriately sized for the application. The gas is passed through the absorber and the CO2 is removed by a base catalyzed chemical reaction, converting the CO2 to Calcium Carbonate that is retained within the absorber. The absorber will have a finite life based on the quantity of Soda lime contained and the level of CO2 within the treated gas. The absorber will remove all of the CO2 (if appropriately sized for the application) and once the Soda lime is consumed, CO2 breakthrough will occur and the CO2 level in the exiting gas stream begins to increase.When put in contact with an acidic gas like CO2, a strong, exothermic (heat producing) reaction takes place that gives off water and binds the CO2 by forming a stable Calcium Carbonate. When binding to other acidic gases, other calcium or sodium salts are formed. The Soda Lime offered here contains a color indicator that aids in indicating the useful life of the Soda Lime. As the Soda Lime becomes less effective at binding CO2, the color of the Soda Lime changes from pink to white. This color change should not be the sole method of determining when to replace the absorbent, but it is an indication of use.

Chemical Properties of Gripo Sorb:
The primary constituents of soda lime include:
Calcium Hydroxide - Ca(OH) 2 (about 70-80%), Water - H2O (about 16 to 20%), Sodium Hydroxide - NaOH (about 1-2%). Loss on drying (in%):moisture content 15 to 20% Moisture Absorb (in %): Not less than 7.5% Carbon dioxide absorbing capacity (in %): not less than 20%

Chemical Reactions that take place to bind Co2 :
First the gaseous Co2 reacts with water to form carbonic acid - H2CO3. Then the NaOH reacts with the carbonic acid to produce Na2Co2 and H2O. The Na2Co2 reacts with the Ca(OH)2 that has been disassociated into Calcium and Hydroxide Ions. (Ca++ and OH-) to produce CaC02 (calcium carbonate, otherwise known as limestone.) The CO2 is now in a relatively stable state. There is a net production of three H2O molecules for every molecule of CO2 which is taken in.

Disposal
Exhausted or waste Soda Lime will contain some residual alkalinity, but can normally be disposed off at a suitable landfill site, etc

Mesh Size of Gripo Sorb:
4mm 8mm grade is the most popular, and is probably adequate for diving and medical purposes.

Color Indicator
The Soda Lime offered by Gripo Laboratories contains a color indicator. As the Soda Lime becomes less effective during use, the granules temporarily change from pink to white color. This color change should not be used to determine when to replace the absorbent, but simply as an indication of recent use.
Gripo Laboratories also manufactures Soda Lime (without indicator) i.e. white color granules that do not change in color on Co2 Absorption.

Particle Shape
The majority of Soda lime grades are now produced with an irregular shaped profile giving a higher surface to volume ratio compared with other classical soda lime products. In addition, the irregular shaped profile ensures maximum CO2 penetration into the particles, by minimizing the distance to the center of the particle, thereby increasing the CO2 capacity of the product. Intrinsic capacity measurements have demonstrated that Gripo Sorb has significantly higher capacity for carbon dioxide absorption compared with other manufacturer products.
The water content can also be varied depending on the application.

Particle Size
Another key factor in the performance characteristics of Soda lime is the particle size distribution. Particle size has an effect on the speed of reaction, which in turn affects the volume of the reaction zone and the capacity of the absorber containing the Soda lime. In general terms, the smaller the particle size, the faster the reaction and the smaller the reaction zone volume. However, the smaller the particle size, the greater the pressure drop across the absorber which in some applications (particularly breathing applications such as diving rebreathers and medical anesthesia) is a critical factor in absorber design. Therefore a well design particle shape/size will look to optimize these effects - an area where Gripo Laboratories has proved extremely proficient.
In summary, compared with other classical soda lime products, Gripo Sorb has a high absorption capacity for carbon dioxide, low dust levels, and excellent attrition resistance.

TECHNICAL ASSISTANCE
Gripo Laboratories maintain the capability to provide a high level of technical support, according to the needs of the customer. Based on our extensive experience we can offer assistance with the sizing and design of Soda Lime.

QUALITY
We follow strict control, and batch acceptance criteria. Our medical grade soda lime test methods also conform to pharmacopoeia standards. Gripo Sorb is manufactured under rigorous Statistical Process operations and is governed by Standard Operating Procedures, which form the basis of our quality system.

Medical Applications:
Gripo Sorb is used in medical applications for removal of carbon dioxide from breathable gas in anesthesia circuits and in hyperbaric oxygen treatment chambers. Gripo Laboratories manufactures Soda lime for many of the world's leading medical equipment manufacturers.

Medical grade Soda lime is produced as per pharmacopoeia standards. Medical grade Soda lime is a carefully controlled mixture of Calcium and Sodium Hydroxides, in the form of irregularly sized particles of 4mm to 8 mm. The particle shape is key to the high carbon dioxide absorption capacity of medical grade Soda lime. The particles are extrudates with an irregular shaped profile, giving a higher surface to volume ratio compared with other soda lime products. In addition, the irregular shaped profile ensures maximum CO2 penetration into the particles, by minimizing the distance to the center of the particle, thereby increasing the CO2 capacity of the product. Exhaled gases are circled back to the canister where Co2 absorption takes place and water and heat are produced. The warmed and humidified gas joins the fresh gas flow to be delivered to the patient. In Gripo Sorb absorption, the carbon dioxide first reacts with water to form carbonic acid, which then reacts with sodium hydroxide to form a soluble carbonate. The soluble sodium carbonate then reacts with calcium hydroxide to form an insoluble carbonate and replenishes sodium hydroxide. Exhaustion of its activity is indicated by the dye and accordingly the color changes from pink to white due to absorption of carbon dioxide (Co2).

Application in Military
All submarines have a complex air filtration and oxygen generation system, essential for maintaining the atmosphere within the submarine suitable for breathing whilst submerged. An integral part of this system is the carbon dioxide scrubbing system that removes the CO2, generated via respiration, by constant circulation through a scrubber system filled with Gripo Sorb. In addition, an emergency supply of chemical oxygen generators is stored on all submarines for use during maintenance of the central oxygen generation system or when additional oxygen is required due to higher than normal oxygen usage (for example increased navy personnel).

Diving and Safety Applications:
Gripo Sorb removes carbon dioxide from the exhaled breath of a diver using a rebreather. It is designed for use in a variety of applications but includes special characteristics that make it one of the best CO2 absorbents for use in rebreathers. Do not confuse this with some grades not rated for use in a rebreather.
The granules are pink in color, hard and processed to minimize dust formation. It is also porous, and irregularly shaped to provide for a larger surface area.
In diving applications, Gripo Sorb is used to maintain carbon dioxide below harmful levels in both closed-circuit rebreathers and in saturation dive systems for commercial deep sea diving.

Gripo Sorb is available in various packing of 1kg, 2kg, 4kg, 4.5kg and 5 kg Jar, allowing divers the ease of carrying their absorbent on smaller boats, without the need to decant from larger bulk drums.

Petrochemical Industry
In addition, Gripo Sorb is used in the petrochemical industry for removal of trace acidic contaminants (CO2, SO2, H2, S, COS) in the production of high purity hydrocarbons such as propylene and ethylene.

CO2 Absorber Design
When sizing a CO2 absorber for a particular application, it is important to understand the effect of various parameters (flow rate, CO2 concentration, temperature, pressure, humidity etc.) on the capacity and life expectancy of the absorber. Gripo Sorb is not a catalyst; it is an absorbent that converts the carbon dioxide from a gas to a stable solid which is retained within the absorber. It is possible to predict relatively accurately the capacity of the absorber and therefore the life expectancy for a given set of conditions. Variations in the conditions can significantly affect the predicted life expectancy and therefore it is important to understand the operating envelope of any absorber design.

Whilst Gripo Laboratories does not offer engineering design services, we can offer advice on absorber design and can provide predicted performance for a given set of conditions.