Schedule – XXII

Manufacturing process or operation in carbon disulphide plants

1.                  Application - This schedule shall apply to all electric furnaces in which carbon disulphide is generated and all other plants where carbon disulphide after generation, is condensed, refined and stored. This schedule is in addition to and not in derogation of any of the provisions of the Act and Rules made thereunder.


2.                  Construction, installation and operation-


(1)              The buildings in which electric furnaces are installed and carbon disulphide after generation is condensed and refined shall be segregated from other parts of the factory and shall be of open type to ensure optimum ventilation and the plant layout shall be such that only a minimum number of workers are exposed to the risk of any fire or explosion at any one time.

(2)              Every electric furnace and every plant in which carbon disulphide is condensed, refined and stored with all their fittings and attachments shall be of good construction, sound material and of adequate strength to sustain the internal pressure to which the furnace or the plant may be subjected to and shall be so designed that carbon disulphide liquid and gas are in closed system during their normal working.

(3)              The electric furnace supports shall be firmly grouted about 60 centimetres in concrete or by other effective means.

(4)              Every electric furnace shall be installed and operated according to manufacturers’ instructions and these instructions shall be clearly imparted to the personnel in charge of construction and operation.

(5)              The instructions regarding observance of correct furnace temperature, sulphur dose, admissible current or power consumption and periodical checking of charcoal level shall be strictly complied with.


3.         Electrodes -


(1)                 Where upper ring electrodes made of steel are used in the electric furnace, they shall be of seamless tube construction and shall have arrangement for being connected t cooling water system through a siphon built in the electrodes or through a positive pressure water-pump.

(2)                 The arrangement for cooling water referred to in sub-paragraph (1) shall be connected with automatic alarm system which will actuate in the event of interruption of cooling water in the electrodes and give visible and audible alarm signals in the control room and simultaneously stop power supply for the furnace operation and to stop the further supply of water.  The alarm system and the actuating device shall be checked every day.


4.                   Maintenance of charcoal level - When any electric furnace is in operation, it shall be ensured that the electrodes are kept covered with charcoal bed.


5.                   Charcoal separator - A cyclone type of charcoal separator shall be fitted on the off take pipe between the electric furnace and sulphur separator to prevent entry of pieces of charcoal into the condensers and piping.


6.                   Rupture discs and safety seal -

(1)                 At least two rupture discs of adequate size which shall blow off at a pressure twice the maximum operating pressure shall be provided on each furnace and shall either be mounted directly on the top of the furnace or each through an independent pipe as close as possible to the furnace.


(2)                 A safety water seal shall be provided and tapped from a point between the charcoal separator and the sulphur separator.


7.         Pyrometer and manometers -


(1)               Each electric furnace shall be fitted with adequate number of pyrometers to give an indication of the temperature as correctly as reasonably practicable at various points in the furnace.  The dials for reading the temperatures shall  be located in the control room.


(2)               Manometers or any other suitable devices shall be provided for indicating pressure –


(a)       in the off take pipe before and after the sulphur separator; and

(b)       in primary and secondary condensers.


8.         Check valves - All piping carrying carbon disulphide shall be fitted with check valves at suitable positions so as to prevent gas from flowing back into any electric furnace in the event of its shut down.


9.                Inspection and maintenance of electric furnaces -


(1)       Every electric furnace shall be inspected internally by a competent person.

(a)                  before being placed in service after installation;


(b)                  before being placed in service after reconstruction or repairs; and


(c)                  periodically every time the furnace is opened for cleaning or de- or for replacing electrodes.


(2)       When an electric furnace is shut down for cleaning or de--


(a)                the brick lining shall be checked for continuity and any part  found defective removed;


(b)                after removal of any part of the lining referred to in (a) the condition of the shell shall be closely inspected; and


(c)                any plates forming shall found corroded to the extent that safety of the furnace is endangered shall be replaced.


10.       Maintenance of records - The following hourly records shall be maintained in a log book.


(a)                manometer readings at the points specified in sub-paragraph 7(2);


(b)                gas temperature indicated by pyrometers and all other vital points near the sulphur separator and primary and secondary condensers;


(c)                water temperature and flow of water through the siphon in the electrodes; and


(d)                primary and secondary voltages and current and energy consumed.


11.              Electrical apparatus, wiring and fittings - All buildings in which carbon disulphide id refined or stored shall be provided with electrical apparatus, wiring and fittings which shall afford adequate protection from fire and explosion.


12.              Prohibition relating to smoking - No person shall smoke or carry matches, fire or naked light or other means of producing a naked light or spark in buildings in which carbon disulphide is refined or stored, and a notice in the language understood by a majority of the workers shall be posted in the plant prohibiting smoking and carrying of matches, fire or naked light or other means of producing naked light or spark into such rooms.


13.              Means of escape - Adequate means of escape shall be provided and maintained to enable persons to move to a safe place as quickly as possible in case of an emergency.  At least two independent staircases of adequate width shall  be provided in every building housing the furnaces at reasonable intervals at opposite ends.  These shall always be kept clear of all obstructions and so designed to afford easy passage.


14.              Warnings in case of fire - There shall be adequate arrangements for giving warnings in case of fire or explosion which shall operate on electrically and in case of failure of electricity by some mechanical means.


15.       Fire-fighting equipment -


(1)               Adequate number of suitable fire extinguishers or other fire-fighting equipment shall be kept in constant readiness for dealing with risks involved and depending on the amount and nature of materials stored.

(2)               Clear instructions as to how the extinguishers or other equipment should be used printed in the language which the majority of the workers employed understand, shall be affixed to each extinguisher or other equipment and the personnel trained in their use.


16.       Bulk Sulphur -


(1)               Open or semi-enclosed spaces for storage of bulk sulphur shall be sited with due regard to the dangers which may arise from sparks given off by nearby locomotives, etc., and precautions shall be taken to see that flames, smoking and matches and other sources of ignition do not come in contact with the clouds of dust arising during handling of bulk sulphur.

(2)               All enclosures for bulk sulphur shall be of non-combustible construction, adequately ventilated and so designed as to provide a minimum of ledges on which dust may lodge.

(3)               The bulk sulphur in the enclosures shall be handled in such a manner as to minimise the formation of dust clouds and no flame, smoking and matches or other sources of ignition shall be employed during handling and non-sparking tools shall be used whenever sulphur is shovelled or otherwise removed by hand.

(4)               No repairs involving flames, heat or use of hand or power tools shall be made in the enclosure where bulk sulphur is stored.

17.       Liquid sulphur - Open flames, electric sparks and other sources of ignition, including smoking and matches, shall be excluded from the vicinity of molten sulphur.

18.       Training and supervision -

(1)               All electric furnaces and all plants in which carbon disulphide is condensed, refined or stored shall be under adequate supervision at all times while the furnaces and plant are in operation.


(2)               Workers in charge of operation and maintenance of electric furnaces and the plants shall be properly qualified and adequately trained.


19.       Washing facilities -


(1)               The occupier shall provide and maintain in a clean state and in good repair, for the use of all persons employed wash place under cover with at least one tap or stand-pipe, having a constant supply of clean water for every five such persons, the taps or stand-pipes being spaced not less than 120 centimetres apart with a sufficient supply of soap and clean towels, provided that towels shall be supplied individually to each worker if so ordered by the  Inspector.

(2)               All the workers employed in the sulphur storage, handling and melting operations shall be provided with a nail brush.


20.       Personal protective equipment -


(1)                 Suitable goggles and protective clothing consisting of overalls without packets, gloves and foot-wear shall be provided for the use of operatives –


(a)               when operating valves or cocks controlling fluids etc.,


(b)               drawing off a molten sulphur from sulphur pots;


(c)               handling charcoal or sulphur.


(2)                Suitable respiratory protective equipment shall be provided and stored in the appropriate place for use during abnormal conditions or in an emergency.

(3)                Arrangements shall be made for proper and efficient cleaning of all such protective equipment.


21.             Cloakrooms - There shall be provided and maintained for the use of all persons employed in the processes a suitable cloakroom for clothing put off during work hours and a suitable place separate from the cloakroom for the storage or overalls or working clothes.  The accommodation so provided shall be placed in the charge of a responsible person and shall be kept clean.


22.             Unauthorised persons - Only maintenance and repair personnel, persons directly connected with the plant operation and those accompanied by authorised persons shall be admitted into the plant.