ARDC is a vertical cylindrical shell having eccentric rotor. Inside ARDC has a series of mixing & settling zones created by alternating rotating and stationary baffles (see figure 1). Top and bottom of ARDC has decantation zones to decant raffinate and extract phases. The feed/solvent having higher density will be fed from top and feed/solvent with lower density will be fed from the bottom of ARDC. One of the phases will be continuous and other phase is dispersed. Both phases will be effectively mixed and settled using rotating and stationary baffles within ARDC shell. After extraction, Both the extract and raffinate will be collected in tanks after passing through settlers. ARDC will have following advantages:

• • ARDC provides adequate mixing and residence time for the reaction to occur continuously.
  • The two phases can be fed at calculated rate to give the required time for the reaction to happen.
  • As the reaction required a specified temperature, both the phases can be preheated online and the extractor which is equipped with a jacked can be also kept hot by circulating hot water at the required temperature.
  • ARDC require less power as compared to batch reactor.
  • This efficiently designed extractor provides adequate mixing between the phases. This leads to lower feed to solvent ratios. overall requirement can get reduced by ~50 % as compared to batch extraction.
  • One Liquid Liquid extractor can replace all Reactors. This leads to 70% space saving.
  • No manual intervention.
  • Reaction / Extraction and water washing keeps on working continuously without any involvement of manpower.

Technoforce has already designed and built several ARDC type Liquid-Liquid Extractors for various industrial sectors. We also offer other evaporation technologies like Agitate Thin Film Evaporation, Short Path distillation and Drying, Falling Film, Rising Film and Forced Circulation Evaporation, as well as Centrifugal Extraction and Crystallization technologies.

Technoforce is ISO 14001:2015, ISO 45001:2018, ISO 9001:2015 certified company with decades of experience in construction under ASME U stamp and PED/CE mark certification. Technoforce also have Pilot Plants facility in The Netherland and India. Sales office in India and Germany. For more details, visit Technoforce website www.technoforce.net

Batch kettle distillation is commonly used as industrial method to evaporate Cardanol from CSNL. However, batch process has inherent disadvantage of long distillation time. Cardinol is heat sensitive product. Long distillation hours at high temperature catches color in Cardinol. This reduces the Cardinol quality and subsequent reduction in market value. Longer distillation hours can reduce Cardinol yield to 50-60%.

Considering heat sensitive properties of cardanol, its recovery and color can be improved if contact time to heating surface is reduced. Agitated Thin Film Evaporator (ATFE) is best fit for this requirement.

In ATFE, a thin film is formed on inside diameter of shell which is intensely agitated by rotor. The small holdup in the film reduces residence time to a few seconds. The turbulent flow within this thin film narrows the spread in residence time distribution. Required evaporation is achieved in a single pass, avoiding recirculation and repeated exposure of the product to the heated surface. These features provide big benefits while processing heat sensitive products. Also, ATFE can operate at high vacuum [maximum 1 mbar] to keep process temperature low. The product can be distilled with the help of hot oil/Steam heating on the jacket side. The product vapors flow counter currently to the feed and condense in a suitable cooling water condenser. The concentrate from ATFE and distillate from the condenser will be discharged continuously by pump.

Benefits of using ATFE for Cardanol evaporation
Improved evaporated Cardanol colour as compared to batch kettle.
Increased rate of cardinol recovery to 80% and more, due to high rates of heat transfer achieved in ATFE combined with low residence time and high vacuum which limits polymerization.
Better handling of the highly viscous and tarry residue with ATFE rigid rotor design which add value to the customer as the un-polymerised residue is a suitable by- product.
Technoforce has already designed and built more than 300 Agitated Thin Film Evaporators for various industrial sectors. We offer evaporation technologies like Agitated Thin Film Evaporation, Short Path Distillation and Drying, Falling Film, Rising Film and Forced Circulation Evaporation, as well as Liquid-Liquid Extraction and Crystallization technologies.

Technoforce is ISO 14001:2015, ISO 45001:2018, ISO 9001:2015 certified company with 2 decades of experience in construction under ASME U stamp and PED/CE mark certification. Technoforce also have Pilot Plants facility in The Netherland and India, sales office in Germany. For more details, visit Technoforce website www.technoforce.net.

Various types of methods are used to treat concentrated wastewater. Most conventional methods operate in batch mode, which involves filtration or kettle drying. In filtration method, mother liquor has to be recycled for concentration, which involves repeated use of energy to evaporate same liquid. Also, sludge from the filter contain high amount of water, which is expensive to dispose. In kettle drying method, kettle filled with wastewater is heated indirectly with hot utility on jacket side. This technique involves high energy consumption and longer hours for drying. Also removing sludge after drying become difficult task which involves lot of manual work. This leads to unsafe and messy operation.

Commonly used continuous method is spray drying. This is direct contact drying where hot air is in direct contact with wastewater droplets. In this case, energy efficiency is low because of inefficient contact with hot medium. Also size of the plant is huge and number of equipment involve are more. Evaporated water along with flue gases discharged to outside air. Hence evaporated water cannot be recovered. This technique is not environment friendly and less energy efficient

The Technoforce Sludge dryer is example of indirect contact drying method. Agitated Thin Film Drying technology is used in this type of dryer. Sludge Dryer consists of a vertical cylinder fitted with a heating jacket. The feed material is pumped continuously to the feed nozzle on top of the equipment. By gravity it flows down and is spread uniformly to a thin film on the inner wall of the Sludge Dryer by a fast-rotating agitator. The heating jacket is heated by steam or thermal oil and transfers the heat to the evaporator. Evaporated vapors from feed film travel to an external condenser while the feed material turns into slurry, sludge, paste and finally dry powder that is collected at the bottom. For wastewater applications, the dryers are often run under atmospheric pressure. This leads to ease in powder collection.

Rotor design is crucial to be successful in the wastewater drying process. Most wastewater feeds are sticky in nature. During drying process, solids stick to the inside wall of Sludge Dryer should be removed continuously to keep surface clean. For this purpose, Zero clearance rotors having hinged blades are used. These hinge blades can touch the shell and wipe the solid built up. (Refer figure 3) Blades are sturdy in design and can handle various types of wastewater.

Agitated Thin Film Drying is highly energy efficient process. Because of the compact design, good control over operating parameters; Sludge dryer become very easy to operate and require less space. One can vary dryness of the solids from dryer based on requirement by simply changing the feed rate or heating temperature. Evaporated water can be condensed and reused.

The indirectly heated sludge dryer eliminates air pollution and gives unmatched thermal efficiency of more than 90 % which is way higher than spray dryer. Overall, 75% space saving can be achieved as compared to similar size spray drying plant.

Technoforce has two types of Sludge Dryers based on their orientation, i.e., vertical and horizontal. Sludge Dryer – Vertical suits well for feeds in the form of solutions or slurries which are pumpable. Sludge Dryer- horizontal is versatile alternative. It is suitable for solutions, dilute slurries, thick slurries, pastes or filter cakes.
Technoforce has already designed and built more than 150 Sludge Dryers for various industrial sectors. We also make Agitated Thin Film Dryers (ATFD) specially designed for product drying applications. We offer other evaporation technologies like Agitate Thin Film Evaporation, Short Path Distillation, Falling Film, Rising Film and Forced Circulation Evaporation, as well as Liquid-Liquid Extraction and Crystallization technologies. Technoforce is ISO 14001:2015, ISO 45001:2018, ISO 9001:2015 certified company with decades of experience in construction under ASME U stamp and PED/CE mark certification. Technoforce also have Pilot Plants facility in The Netherland and India. Sales office in India and Germany. For more details, visit Technoforce website www.technoforce.net