Bevel-helical gear units B2 lid shaft with parallel key HSH n A n B2-FV-10B

Flender/Flender Gear Units/Bevel-helical gear units B2

nt, or frictional removal (attrition) of mucilage. simple and quick method ofremoval of mucilage is to mix equal weights of pulped coffee and water and heat to 5 /H1C as quickly as possible when the structure of pectic materials of the mucilage gel is ruptured. The coffee may be washed afterward by contact with warm water for about3 minutes. The only constraint on this method is the cost of the fuel. 3.2.3.3 Treament with Alkali Removal of mucilage by treatment with alkali takes 1.0 for . arabica and 1.5.0 forC. robusta . The beans obtained after pulping are drained of excess water and spread out in the vats uniformly and furrowed with gorumanes . 1% solution of caustic soda (sodium hydroxide) is evenly applied into the furrows by using can. About 1 kg sodium hydroxide dissolved in 1 water is sufcient to treat 1 to 1 of wet parchment. The parchment is agitated thoroughly by means of gorumanes to produce contact of thealkali with the parchment and trampled by feet for about half an hour. When the parchmentis no longer slimy and makes rattling noise, clean water is let in and the parchment iswashed clean with three or four changes of water. 3.2.3.4 Enzymatic Removal of Mucilage Commercial formulations of pectinolytic enzymes can be used to hasten the fermentation process. The length of fermentation can be reduced by use of pectinolytic enzymes; bothconcentrations of enzymes and temperature of the ambient air determine the fermentationtime. Generally the pulped coffee is taken to digestion tanks every evening and fermenta- 7 Ramalakshmi and Raghavan Fig. 6 Construction details of typical fermentation tank, showing ( grid and ( sluicegate. (From Ref. 1. Reproduced with permission.) tion is carried out overnight. Alkali treatment requires strict control of the time of contact with alkali so that the quality of the coffee is not affected. 3.2.3.5 Attrition MethodSome pulpers (Raoeng and Aquapulper) pulp and demucilage the beans in one operation. These machin