trONNEETINGINIIUSTRY.COiTL',PPOCESS& CONTROL Focus Food prucessing & packaging

Extrqction methods optimise yield

Herbal extraction methods are used to produce active ingredients andcolours for medicinal, food, pharmaceutical and cosmetic products. sPXextractors are designed to ensure yields are high and the process efficient

machine. The raw material is notstirred during the process, leaving thesolid bulk within the vessel undis-turbed. This is combined with internalfiltration during the extraction cycle toensure the liquid can be easilv dis-charged at the end of the cyc1e. Thesystem design requires less volume forextraction and enables the solvent tobe handled in buffer/storage tanks.

Pressure can be varied from -1 to 24bar for best process results and the fil-tration within these vessels is a sim-pler, more efficient method ofextraction. Integrated solvent recoveryand liquid discharge supported by avacuum further improve efficiency.

In order to ensure a good under-standing of the application and itsgoals, SPX operates a test centre inWarendorf, Germany. Here, pilotextraction, evaporation, distillationand drying can be carried out to trialprocesses and parameters used toensure an efficient process with opti-mised yield and high quality results.Pilot plants can also be rented for useat a customer's site. Use of the testcentre and pilot plants can help deter-mine the best type and ratio of solventto raw materiai for new products andevaiuate economic efficiency beforeinvesting in full-scale productioncapability. It also means the design ofthe final system can be optimised tomeet the application needs.

SPX e&e Series technology is engi-neered to meet the requirements ofeach specific application. It isdesigned to be flexible, enabling adap-tion to different product batches,changing consumer demands and'in-products' in the market place. Systemscan be designed to handle hundreds ofdifferent raw materials to produceIarge batches or just a few hundredIitres of extract.

As mentioned previously, becauseyield is of primary importance, theextraction vessels are designed to max-imise yield and process efficiency.Automatic filling along with quick andeasy discharge of raw material andcleaning enable increased productivitywith rapid change over betweenbatches. The process can offer steam-ing, vacuum stripping, percolation andsolvent recovery wiih batch sizes fiom50I up to 20 cubic metres. The SPXextraction plants have easy accessibii-ity and low maintenance needs withassured hygienic standards main-tained through clean in place [CIP)and sterilise in place (SIPI capability.

SPX Flow Technologywwuspx.c0m

ftiHi":'lffi,r,ir".#Asian and Chinese medicine, medici-nal products, instant tea drinks andactive ingredients and colours for usein the food and beverage, pharmaceuti-cal and cosmetics industries. Extractiontechnology has been around for manyyears, but the equipment from SPXemploys innovation to ensure yieldsare high and the process efficient.

The method for herbal extraction isvery similar to making a cup of tea.Raw material is placed in a percolatorand a solvent added. Parameters thataffect the quality of the resulting prod-uct include temperature, time in thesolvent and ratio of solvent to activeingredient. Industrial scale processesproduce a few tonnes of product perhour and solvents used include fluidssuch as ethanoi, acetone or ethylac-etate as weli as water. The processtemperature depends on the liquidutilised and typically varies lrom 70'Cto 90'C or up to 100'C when water isbeing used.

Some solvents, such as acetone, arehazardous and may have regulationsassociated with management of theirresidue. To ensure careful treatment ofsuch substances from a health andenvironmental standpoint, steam canbe applied though the wet cake ofexhausted material in the vessel, caus-ing the solvent to evaporate. Thevapours created, are guided to a con-densing system and discharged either

for recycling within the system or to betransported to a recycling plant,depending on system requirements.

Traditional extractors are cylindri-cal with ingredients being added at thetop. The mixture is then stirred tobring the solvent and raw materiai incontact. However, this method createsissues in the process with dust beingswirled through the extract fluid,impacting the downstream process.Separating the liquid and solids at theend of the process for discharge alsobecomes more complicated.

SPX percolators have a conicalshape which distributes the soiventhomogenously while enabling easydischarge of material after the process.The liquid passes between channels inthe particles of the raw material andthrough a sieve at the bottom of the

The e&e Serieslechnology is engi-neered l0 meet therequirements oleach specilicapplication

Syslems can bedesigned to handlehundreds ol diller-enl raw materialslo produce largebalches or iusl alew hundred litresol exlract

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