RFD/RFP facility comprising bleaching + mercerising + stenter facility.
Dyeing and printing are processes employed in the conversion of raw textile fibres into finished goods that add much to the appearance of textile fabrics.
The envisaged equipment consist of fabric entry device, washing compartment, chemical dosing station, chemical applicator, steamer, washing compartment and plaiting device. In a CBR, fabric is treated with caustic soda, hydrogen peroxide and wetting agent etc. The advantages of such a CBR may be viewed in terms of removing all added (after sizing) and natural impurities from cotton fabric to make it absorbent and white. It is a single batch process and is eco friendly where no hazardous chemicals like hypo-chlorite are used.
With respect to capacity utilization, bleaching equipment needs to operate on continuous basis. This is, because, considerably higher amount of expensive steam is required for initial heating purposes (of total about 1200 kgs.). Continuous operation on 22 hours per day basis is therefore necessary to avoid heating loss between shifts. About one day every week the facility may be shut down. The installed capacity of the envisaged equipment is 1 lakh metre per day on the basis of continuous shift operations. It may be conservatively assumed that the equipment will largely use 80-100 GSM fabric on single layer basis.
Mercerizing equipment consist of feeding entry, caustic impregnation tank, stabilisation tank, ashing compartment, and a plaiting device. The process involves treatment of grey fabric with caustic lye (liquid form) concentration of approximately 250-300 gms per ltr. The advantage of the equipment is to impart lusture in the fabric. Improve dye ability, dimensional (length and width) stability and tensile strength.
The equipment identified in this context comprises a Continuous Chainless Mercerising Machine with capacity of 1 lakh metres per day.
A stenter consist of feeding entry mangle drying chambers (about 6 numbers), plating device, and width control device. A stenter can dry fabric, finish fabric (soft & stiff finish) as per requirement and facilitate heat setting which is essential for polyester fabric and ensure uniform width. A thermic fluid heater provides temperature of 160 Celsius for cotton and 190 – 210 C for polyester heat setting.
A stenter effectively facilitates drying, finishing and fabric width setting (of cotton fabric) and heat setting (of polyester fabric). High temperature oil (thermic fluid) circulates inside the machine and hot air is blown through these oil radiators onto the wet fabric for drying. The machine runs on thermic fluid oil and hence heat-up time for oil firing, cooling time in case of stoppage etc., merits continuous operation to optimise resource outlay. This is present industry practice and recommended by equipment and technology service providers. The equipment is oil heated, and no steam is required.
The critical equipment envisaged for the CFC is a hot air stenter of 1 lakh metres per day as installed capacity.
