Cottonseed, as the by-product of cotton ginning operation, is covered with fibrous lint. The cottonseed is mainly made up of inner kernel, usually called "meats". This meaty portion contains all the oil as well as proteins, and it is enclosed in the fibrous hull. Over the hull stick out the cotton fiber which escape the ginning and left on seeds. These cotton fibers are called "lint".
By processing cotton seeds, we can get maximum benefits. The inner kernel can be planted, fed to livestock, made into cottonseed oil for human consumption, used for fertilizer, or used in products like lotions and soap. The lint we get from cotton delinting has wide application in cotton blanket, sweat shirt, paper board industry and cotton pulp, etc. Therefore, the cottonseed delinter is very essential in cotton processing.
Methods of Cottonseed Delinting
Two general methods have been developed for removing the lint from cottonseed, which are removing the lint by acid and by delinter machine respectively.
The acid delinting of cottonseed has been used extensively, particularly when the seeds are used for planting. Both sulfuric acid and hydrochloric acid have been used for acid delinting respectively. Due to the generation of heat from the reaction of acid with the moisture, the short cotton fibers on the seed would quickly disintegrate. The residue can be washed away with water. After washing, the seed need to be neutralized with soda ash, lime or anhydrous ammonia, which is regard as the wet acid method. However, the concentrated sulfuric acid is extremely corrosive to machinery and dangerous to handle. Some serious problems could emerge, like consuming a large amount of energy to dry the seed and causing soil and water pollution.