FACT-Petrochemical Plants of Fertilisers and Chemicals Travancore Limited (FACT), Udyogamandal Complex , Kochi is in the business of manufacture and marketing of quality Caprolactam with production capacity of 50,000 MT of Caprolactam per annum. Caprolactam is a monomer of Nylon-6 which is a base material for a number of industrial products. Caprolactam is used primarily in the production of nylon 6 fibers and nylon 6 engineering resins and films. More than half of world caprolactam consumption is for nylon 6 fibers and more than one-fourth is for nylon 6 resins and films; the remainder is accounted for by trade in polymer chip. Nylon 6 fibers are used in the textile, carpet, and industrial yarn industries. Nylon resins are used as engineering plastics, with applications in the automotive industry, specialty film packaging for food, and wire and cabling. The process employed for the Caprolactam manufacture by FACT is the Raschig Route.
The license and process know-how was supplied by M/s. Stamicarbon b.v, a subsidiary of Dutch State Mines (DSM), The Netherlands. The basic engineering was done by M/s. Chiyoda Corporation, Japan and the detailed engineering was done by FEDO (FACT Engineering & Design Organisation) , the design and engineering unit of FACT. Along with the 50,000 MT of Caprolactam produced per annum by product of ammonium sulphate of 225000 MT per annum is also produced.
A brief description of the Caprolactam Manufacturing process is given below :-
FACT-Petrochemical Plants comprises of following main sections :-
The foundation stone of the project [earlier known as the Ammonium Sulphate Caprolactam project
(ASCL project)] was laid on 8th March 1984.
The plant was commissioned on 25th October 1990. The plant was dedicated to the nation by Hon Prime Minister of India Shri Chandra Shekhar on 16th March 1991.
i) Anone Plant Benzene hydrogenation Cyclohexane oxidation
ii) HYAM (Hydroxylamine sulphate) Plant
iii) Lactam Plant
Besides this Effluent Treatment Section with Aerobic and Anaerobic treatment & Offsites area with ancillary facilities are also available.
The operations of the above sections are briefly described below.
In Benzene Hydrogenation Section, Benzene is catalytically hydrogenated to produce Cyclohexane. Cyclohexane is oxidised with air to Cyclohexanol and Cyclohexanone in a series of stirred reactors in the presence of a catalyst. A number of other products are also formed during the oxidation, but the quantity of such products is carefully controlled within limits by suitably adjusting reaction conditions. These products are removed by saponification using caustic soda. Unreacted cyclohexane and products cyclohexanol and cylcohexanone are separated in a series of distillation steps. Cyclohexanol is converted to cyclohexanone in a catalytic dehydrogenation reaction.The crude cyclohexanone is then further purified.
Hydroxylamine sulphate (HAYAM) Plant
Hydroxylamine sulphate is prepared using the raschig process. Ammonium carbonate solution is prepared by absorbing carbon di-oxide in an aqueous ammonia solution. A mixture of no and no2 is prepared by oxidising ammonia over platinum catalyst. This mixture is then absorbed in the ammonium carbonate solution to produce a solution of Ammonium Nitrite. Ammonium Nitrite is then reacted with sulphur di-oxide to obtain Hydroxylamine Di sulphonic Ammonia, which is further hydrolysed with water to produce hydroxylamine sulphate and Ammonium Sulphate.
Lactam Plant & Bagging
Hydroxylamine sulphate is reacted with cyclohexanone resulting in the formation of cyclohexanone oxime &
AmmoniumSulphate. The cyclohexanone oxime separated as an organic layer from the above mixture is then subjected to a reaction called ‘Beckman Rearrangement. Chemically, both cyclohexanone oxime and Caproclactam have same molecular formula, but different molecular structure.This reaction takes place at elevated temperature in the presence of oleum. The oleum does not take part in the reaction and it is later converted to Ammonium Sulphate by adding ammonia to the reaction mixture.This gives a two-phase mixture. one phase containing caprolactam and the other, Ammonium sulphate. The crude Caprolactam solution separated from this is then subjected to a series of purification steps to remove the various impurities. The Ammonium sulphate solution is sent to the crystallisation section of the Ammonium Sulphate Plant . Final product lactam from the previous step is in the form of a liquid with a solidification temperature of 69 degree Celsius. This is then flaked in a standard drum flaker cooled with water. The flakes are then bagged in 25 kg bags and despatched.
The Pollution Control Facilities consist of Soda Ash Recovery Plant, Ammonium Sulphate Purge Incineration Plant, Effluent Treatment Section with Aerobic and Anaerobic treatment.
Ancillary facilities consist of :-
1) Steam Generation & Captive Power Plant of 16 MW.
2) Water Demineralisation Plant.
3) Cooling water treatment Plant.
4) Nitrogen Plant & Compressor house.
5) Main Tank Farm.
6) Ammonia Storage & Handling system.