USE OF CHROME MANGANESE AUSTENITIC STAINLESS STEEL IN SUGAR INDUSTRY - A CONCEPTUAL APPROACH

摘要

The acidic nature of the sugarcane juice and toxicity associated with gaseous products encountered in the manufacture of sugar, pose a serious challenge to sugar industry. Trend has been to progressively use stainless steels to overcome the problem. The most common stainless steel grades currently being used are AISI 304 and 3Crl2/AISI 409. Substantial use of 304 will render the investment cost very high. Based on an elaborate corrosion study in sugarcane juice, use of four indigenously manufactured Chrome-Manganese austenitic stainless steels are suggested to keep the performance-cost ratio reasonably high.Sugar manufacturing in India and in most of the tropical countries is a booming enterprise. Sugar production being a seasonal cyclic activity, continuous uninterrupted production in a narrow time period is essential for viability of a plant. Therefore, material plays a very important role in production cost economy. The traditional structural material, carbon steel is progressively being replaced by stainless steels in order to increase the life of vital components, reduce unplanned down time, reduce annual maintenance cost and above all to improve the hygienic condition of the mill and the product. Among the stainless steels, the austenitic type 304 and ferritic type 409L are currently popular in sugar industry in India. In Australia, South Africa and in some European countries, 3Crl2, a 12%Cr steel is a major stainless steel material used in sugar mills. The objective of using stainless steel is to at least increase the life span of components to 10 years from present level of 3-4 years where carbon steels are used. The essential properties that are looked for are: a) Corrosion and erosion resistanceb) Abrasion resistance - Particularly resistant to wet abrasion.