Study On Steam Step Utilization On BOPP Production Line

The BOPP (Bi-Oriented Polypropylene film) is widely applied in the fields, such as foodstuff, clothing, cigarette packing and adhesive tape manufacture. Since the 1990's until now, the domestic BOPP industry enters a higher speed development period, capacity has enhanced by a big margin, in recent years, the demand for BOPP increases steady in particular by 10-12% speed.The main technology and equipments of Fushun BOPP production line were introduced from Japanese Mitsubishi Corporation, this production line signed the contract in 2002, and it put into operation in 2003. Main equipments of this production line were introduced from the abroad and relative utilities and auxiliary equipments were supplied by domestic manufacturers. After the operation of the plant, the operation is normal, and produced qualified and acceptable products, but the load of utilities is too high, with higher energy consumption, all of these increase the cost of the products, influence the improvement of economic results. This paper will study and discuss on the technical reformation program of steam step utilization, on the basis of investigation in the worksite and analysis on the original design process.In the course of the opera;tion of FuShun BOPP production line, the longitudinal stretch and the transverse stretch are the crucial processing steps, Moreover the energy consumption is higher, in which longitudinal stretch needs 2.3t/h 1.0MPa heating steam, and the transverse stretch needs 4.5t/h 3.5MPa heating steam.In this paper, in view of existing situation of vapor system of 20,000 t/a BOPP plant, adopts the principle of vapor jet pump. With technical reformation, about 0.8 t/h 1.0MPa steam can be saved for 20,000 t/a BOPP plant, and in the meantime decrease the load of cooling tower up to 50%, furthermore, the investment for this program is less and the return is faster, all the data put forward can be used in technical reformation of existing production plant directly.