We provide dewatering solutions for paper mills. Dehydration of fabrics on paper machines consumes energy to physically remove water particles. If the vacuum pump is worn and the air flow drops to 60% of the original flow, energy and pump seal water will be wasted, and the white water must be removed from the paper by steam in the dryer part, so as to vaporize the water with more energy / pound water removed at a higher utilization rate than the water used in the vacuum pump.
In order to ensure economic performance, we test the performance of dehydration equipment (such as vacuum tank, pipeline and vacuum pump). We use the orifice method to measure the actual air flow of the pump at the vacuum level. Performance test results are written into the report, which shows the total wasted energy and seal water included in the total cost of ownership life.
The paper machine uses vacuum in the forming, pressing and drying parts. In the forming process, there is the largest flow demand. Vacuum and gravity draw a lot of water out of the liquid material (the solid content in the headbox is only 4%). This is called sheet formation, where the fibers start to diffuse and consolidate into a thin mat. In this part, it looks like white wool. The wet web is then lifted from the screen and extruded between a series of presses, then the moisture content is reduced to about 50% by squeezing between rollers. It then bypasses a series of cast iron cylinders in the drying zone, heats to a temperature of more than 200 ° F, and then dries. Here, the water content falls to 5% to 8% of its final level.
The vacuum process is located in the press section. In this part of the paper machine, air is drawn through the web in a long slot at the top of a box called the uhle box. There are several uhle boxes in the press section. Each box is designed with exactly suitable slot geometry and vacuum degree, which can gradually remove water.
The vacuum pump serves the press part of paper machinery . It uses a positive displacement vacuum pump called liquid ring vacuum pump. The cylinder wall of the pump uses “liquid ring”, while the rotor is immersed in the ring. They can bear high condensable load, and are common in wet applications such as pulp and paper. Centrifugal air extractors have been involved in the field of pulp and paper, and have effective regulation capacity. If the paper machine changes products and requires multiple vacuum set points, it is very valuable. Liquid ring vacuum pump is usually the most economical choice in the typical paper machine which always runs the same product. They are quite efficient and highly reliable.
Vacuum Pumps For Paper Machinery