100,000 t-a PVC centrifugal drying device running

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100,000 t / a PVC centrifugal drying device running Summary

Aspects were improved. (1) strict order of open parking. (2) control the air drying tower into the air volume to maintain a certain pressure. (3) a reasonable allocation of good air drying tower and cyclone drying bed temperature, avoid air drying tower bottom temperature is too high. (4) minimize the number of open parking drying device. A short time the first production unit continued failure, to minimize the resin into the volume of air drying tower to maintain continuity of production. 3 3.1 centrifuge equipment modification modified feed tube with the spiral centrifuge feed pipe wall there is a certain gap, due to memory a certain pressure centrifuge, the feed process, there will be some PVC materials accumulate in the gap. When the accumulation to a certain extent, the friction in the high-speed spiral centrifuge,[link widoczny dla zalogowanych], this part of the accumulation at high temperature to form plasticized PVC film, even when serious decomposition of color, resulting in excessive product impurities. This issue, initially taken to dismantling the feeding tube regularly clean way to solve the plastics film, but this does not result in a continuous feed centrifuge, centrifuge lower utilization. So by comparing different manufacturers of centrifuges, centrifuge the original transformation of the feed tube feeding tube double jacket, the jacket open end of a number of small larvae L, during feeding through water jacket layer. Feeding process to ensure that the feed tube and spiral centrifuge the gap between the wash water has always been to prevent this accumulation of PVC to avoid plastics film,[link widoczny dla zalogowanych], to ensure continuous smooth operation of the centrifuge. Increase the flow of flushing water jacket is small, the total feeding quantity of centrifuge little influence, or even negligible and will not cause a reduced ability centrifugation. 3.2 centrifuges centrifuges under the slurry into the hopper transformation temperature about 75 ��. Centrifugal dewatering process in a large amount of water vapor,[link widoczny dla zalogowanych], because water vapor condensation. Often under the hopper wall so that the centrifuge adhesion resin, along with increasing the thickness of adhesive resin, the resin in the next hopper is easy to bypass, resulting in the centrifuge stopped dancing, affecting the normal operation of the centrifuge. During operation, often with a wooden hammer to be laid to prevent the resin hopper bypass. In addition, the centrifuge during operation, due to centrifugal force, centrifuge memory in a certain pressure, leading to some water vapor entrained into the centrifuge bearing resin particles, and then enter the centrifuge lube oil system, lowering the centrifuge bearing life . Therefore,[link widoczny dla zalogowanych], to the extent possible, the centrifuge to remove water vapor and under pressure to vent out by changing the taper and the next hopper open hopper vent. The centrifuge cutting smooth and timely discharge centrifuges pressure off, and the lubrication system is no longer the centrifuge and resin mixed with water, thus ensuring long-term operation of the centrifuge at full load. 4 energy saving measures 4.1 Reuse of steam condensate from the steam condensing water heater drying temperatures of up to 90 ��, its composition and the water is almost the same (see Table 1). Therefore, the decision to dry and steam condensate water for the polymerization feed. As the steam condensed water vapor within the entrainment of a considerable part. Increase in a heat exchanger and cold water to heat, heat the cold after the heat of pure water tank of pure water pumps were, after cooling the steam condensate is collected into the heat sink, heat pure water tank hit by the water pump. Table 1 steam condensate and water quality comparison chart component p (Ca2 ~) / (mg �� L-) p (Mg2 ~) / (mg �� L-') p (Fe2 +) / (mg, L) pH of this Since the operation transformation, PVC product quality is not significantly affected. No direct discharge of condensed water vapor, instead of a lot of water, greatly reducing the cost of production. 4_2 mother liquid water reuse to drive early. Mother liquor discharged from the centrifuge through a simple two-stage water directly into the water after deposition, resulting in increased costs of sewage pollution and ecological environment. Meanwhile,[link widoczny dla zalogowanych], the preparation of acetylene pure liquid water system caused by the use of industrial equipment and pipe scale serious. This. Adds a special preparation of equipment, used interchangeably, but the system needs to reduce the amount of switching or stopping to be, a continuous smooth operation of the system. Of the mother liquid water and industrial water quality analysis (see Table 2) found that the mother liquor COD and suspended solids in the water except the water higher than the industry, its Ca, M concentrations much lower than in industrial water. So, decided to use water instead of liquor preparation of industrial water use water as acetylene, and by adding filters and plate heat exchanger to reduce the mother liquor suspended solids and reduce the water temperature. Table 2 The mother liquid water and industrial water analysis table component p (Ca2 +) / (mg �� L-) p (M) / (mg �� L-) pH Temperature / �� liquor suspended solids of water since water is used for the preparation of acetylene, acetylene preparation system is running a continuous, smooth, no recurrence of acetylene caused by scaling down or stop the amount of accidents, parking dismantling preparation system, no scale in equipment and pipe. Received date :2009-07-04