Method of washing a textile product

Abstract

There is provided an excellent method of washing a textile product in a treating method using a treating apparatus of the type, such as a liquid current treatment apparatus that treats a textile product by circulating the treating liquid, which washing method is capable of completely or substantially completely removing oligomer, dyeing residues or the like and is unlikely to cause insufficient washing or excessive washing. A method of washing a textile product includes a high-temperature treating step of treating a textile product by loading the textile product in a treatment tank, and bringing a treating liquid circulating the inside and outside of the treatment tank into contact with the textile product while heating the treating liquid to a high temperature by an indirect heat exchanger disposed in a portion of a circulation passage of the treating liquid; and a liquid replacement washing step of gradually supplying a washing water into the treatment tank while gradually discharging the high-temperature treating liquid from the treatment tank, during which the high-temperature treating liquid to be discharged is directly heat exchanged with the washing water to be supplied, and lowering the liquid temperature within the treatment tank to a predetermined temperature while making the amount of the high-temperature treating liquid equal to the amount of the washing water to be supplied, thereby keeping the amount of liquid within the treatment tank constant, in which an optimum value of the temperature gradient in the liquid replacement washing step is previously set, so that the actual temperature gradient is brought at or close to the optimum value by heating or cooling the treating liquid by the indirect heat exchanger.

1 . A method of washing a textile product, which comprises a high-temperature treating step of treating a textile product by loading the textile product in a treatment tank, and bringing a treating liquid circulating the inside and outside of the treatment tank into contact with the textile product while heating the treating liquid to a high temperature by an indirect heat exchanger disposed in a portion of a circulation passage of the treating liquid; and a liquid replacement washing step of gradually supplying a washing water into the treatment tank while gradually discharging the high-temperature treating liquid from the treatment tank, during which the high-temperature treating liquid to be discharged is directly heat exchanged with the washing water to be supplied, and lowering the liquid temperature within the treatment tank to a predetermined temperature while making the amount of the high temperature treating liquid to be discharged equal to the amount of the washing water to be supplied, thereby keeping the amount of liquid within the treatment tank constant, in which an optimum value of the temperature gradient in the liquid replacement washing step is previously set, so that when the actual temperature gradient is larger than the optimum value, the treating liquid is heated by the indirect heat exchanger, and when the actual temperature gradient is smaller than the optimum value, the treating liquid is cooled by the indirect heat exchanger, thereby bringing the actual temperature gradient at or close to the optimum value.