The cost of sugar production can be reduced by 20 to 25% through the proper utilization of its by-products
By *Dr. Muhammad Ayoob Shaikh
**Hakim Ali Kanasro
Jan 27 - Feb 02, 2003
Proper utilization of the by-products of sugar industry is also necessary for the development of the industry. It must be taken into serious consideration by the economic planners and entrepreneurs. The cost of production of sugar continuously growing, due to the neglect in the proper utilization of the by-products. If the by-products are used the cost of production of sugar may go down by 20% as 25%.
The main by-products of the sugar industry are:
3) FILTER MUD
In our country some of the molasses is used for producing ethyl alcohol, some is used in cattle feed, about 200,000 tons per annum is used by tobacco, fertilizer and other indigenous industries including Murree Brewery and the maximum quantity is exported.
Study reveals that final molasses contains 30 to 40% sucrose alone or combined with reducing sugar which at present cannot be economically recovered on industrial scale and is thrown away. The loss is estimated about 10% of the total sugar in cane. The control of this loss is, therefore, one of the most difficult problems for the sugar experts. Study further reveals that molasses is industrially most important raw material in the manufacture of variety of products such as; distillery products, chemicals like; lactic acid, citric acid bakers yeast, acetone, butanol, and aconite acid which is an important chemical used in various industries. Presently, the conversion of molasses by the process of fermentation and distillation is extensively used in manufacture of methyl and ethyl alcohol add potable spirit. It can conveniently be converted into absolute alcohol which can be used on an admixture to power alcohol. The following table shows the export of fermentation ethyl alcohol during the period from 1991-92 to 2000-2001.
EXPORT OF FERMENTATION ETHYL ALCOHOL
Value in (000) Rs.
Increase over the period
Source: Federal Bureau of Statistics
ALCOHOL BY-PRODUCTS AND DERIVATIVES
Fuel oil is one of the very important by-products of the distillery and is mainly collected in the rectification columns and consists mainly of amyl alcohol and iso-amyl alcohol carbon dioxide is also one of the important commercial product produced during fermentation at the rate of about 160 kg per ton of molasses of which about 70 to 75% is recovered. The liquid carbon dioxide is extensively used in carbonated beverages, fire extinguishers and food preservation.
There are many other possibilities still to be explored and the field is still fertile one in which important developments may confidently be expected. The following Table-2 gives the molasses production in Pakistan during the period 1991-92 to 2000-2001.
MOLASSES PRODUCTION IN PAKISTAN (TONS)
Increase over the period
Source: Annual Report (2001) Pakistan Sugar Mills Association Sindh Zone p-30
It is evident from the above table-2 that Pakistan on an average produced 1.548 million tons molasses annually during the above said period out of the total production during the period from 1991-92 to 2000-2001, Sindh province shared 38.98%, Punjab province shared 57.84%, and NWFP shared 3.18%. The production of molasses has increased from 1,168,158 tons in 1991-92 to 1,461,954 tons in 2000-2001, thus showing an increase of 25.1% over the period. As the commercial utilization of molasses in the country is limited and a large part of product is exported to the foreign market on premium. The following table-3 shows export of molasses.
EXPORT OF MOLASSES
Value in (000) Rs
Average Price per ton Rs.
Source: Annual Report (2001) Pakistan Sugar Mills Association Sindh Zone p-45
It is evident from the table-3 around 841,500 tons of molasses export during current sugarcane crushing season has fetched around 2,224,645 thousand at an average price of Rs. 2,643.367 per ton. The bulk of quantity of molasses is exported to European countries where it is processed and up-graded to make it usable for industrial purposes, including alcohol and in some edible products.
The sugar mills generally do not have proper storage system of molasses and normally they fill open pits in the ground which are exposed to atmospheric changes as well as dirt. Consequently, most of the leading exporters have already purchased huge quantity of molasses. Near about 400,000 to 500,000 tons and have stored it in tanks at Kyamari, Karachi Sindh.
The other important by-product bagasse is the fibrous material left after the juice has been extracted from sugarcane. This also serves as fuel for running a sugar factory. Bagasse is burnt in the boilers to raise steam. This steam is used for generation of the electricity and as a propellant for the prime movers in the sugar factory. This exhaust steam from the prime movers is utilized to heat and boil the juice and massecuites. Thus a sugar factory is self sufficient in fuel.
In the past, an effort was made to burn total bagasse as the disposal of surplus bagasse was difficult and it presented a great hazard if it was not removed from the factory premises. Bagasse is now, no more considered as waste but has become a valuable source of cellulose as raw material for quite a few industries. Our country being deficit in forest resources, bagasse has come as a very handy raw material to replace wood. The first plant to use bagasse was installed at Crescent Sugar Mills to make fiber-board and particle board. This came into production in 1971 and has been very successful.
A writing paper plant has been setup at Charsada. This utilizes total bagasse from Charsada Sugar Mills instead it material gas as fuel. The study reveals that bagasse is rich in cellulosic materials and can be utilized for pulp and paper, paper board, corrugated board, insulting hard-board products for the building industry and for providing insulation against heat, cold and sound.
Bagasse on dry weight contains about 18 percent lignin, 15 percent water-soluble substances, 45 percent cellulose, 28 percent pentosans and other hemi cellulose. Because of its long, tough, springy character, bagasse is a superior raw material for the manufacturing of insulating building board products and that it is not possible by known means to produce a fiber of similar properties from wood, bamboo, hesian, etc. Intensive experiments conducted in America have shown that fibers of the rind and bundles are excellent for producing writing and fine papers.
BAGASSE IS BIG SOURCE OF CHEMICALS
Bagasse is a source of not only useful fiber but also an excellent source of chemicals like formaldehyde, furfural-dehyde and also plastic materials. Study further reveals that bagasse contains a large proportion of pentosans, it is a very suitable material for the production of furfural which has a very wide range of uses, from the synthetic manufacture of rubber and nylon to the separation of vegetable oil into food and paint oil constituents. Furfural is manufactured either by batch or continuous process of digesting it with sulfuric acid at definite temperature and pressure and separating it from other components. Alpha cellulose is highly purified cellulose used mainly in rayon, acetate fibers, cellophane plastics, and explosives photographic film lacpuers and fine papers.
FILTER MUD OR PRESS MUD
This third by-product is derived from the filter waste in the sugar mill and contains an organic matter as proteins, polysaccharides, starchy gums and waxes, whereas inorganic mater consists of mostly calcium sulphate and calcium phosphate. It is usually used as an organic fertilizer but has also some nutritive value. The process has now been developed to manufacture wax out of it, which is very much used in boot and paint polish.
CONCLUSIONS AND RECOMMENDATIONS
It is concluded from the above study that the sugar industry is characterized by poor utilization of by-products. So the by-products usage remains relatively unsophisticated in Pakistan with the result the cost of cane is born utmost entirely by sugar.
In the light of above conclusion it is recommended that:
1)Molasses are used for manufacturing various goods such as:
(i) Molasses a good food stuff, much used for cooking and confectionery and backers yeast, candies, cosmetics, manufacturing rum.
(ii) Molasses used in fertilizer and tobacco industry,
(iii) Chemicals, like lactic acid, citric acid,
(iv) Acetone, butanol and aconitic acid methyl and ethyl "alcohol add potable spirit", carbon dioxide etc.
But in our country 90% molasses are being exported and earned about $70 millions. If molasses are used for producing above-mentioned products, four times more income can be earned on one hand and on other hand new job opportunities will be provided to the people of the country.
BAGASSE:Bagasse serves as fuel for running a sugar factory. But from bagasse, various new things such as (I) fine paper (II) Pulp (III) Plastic material (IV) Rubber and nylon (V) Paint oil (VI) Sulphuric acid (VII) Photographic films (VIII) Lacpuers (IX) Particle board (X) Corrugated board (XI) Insulating hard board and products for the building & industry etc.
This by-product is used by mills for fuel purposes if gas facility is extended to mills for fuel purposes or cheapest source of energy coal used at the place of bagasse, bagasse can manufacture the above mentioned items and earn million dollars which will be better for the improvement of the economy.
FILTER MUD:From this by-product the other products such as wax, boot polish, paint polish can be manufactured and can increase the national income. Thus the government must extend necessary support for acquisition of technology and project financing for feasibility studies for developing by-product.
1.Various Annual Reports of Pakistan Sugar Mills Association Sindh Zone.
2.Operational Figures at a Glance Sugar Mills in Sindh, Published by Office of the Cane Commissioner Hyderabad, Sindh
3.Various Annual Reports of Pakistan Sugar Mills Association
4.Aslam, Mohammad. Sugar cane and its By- Products in Pakistan, Pakistan Economist, Vol.18, No.6 Finance and Industry Publication Karachi.
*Dr. Muhammad Ayoob Shaikh is senior faculty member of Faculty of Commerce and Business Administration at University of Sindh Jamshoro. ** Mr. Hakim Ali Kanasro is Ex- Director of SZABIST Larkana Campus and presently working as Assistant Professor in Faculty of Commerce and Business Administration at University of Sindh Jamshoro.