390 m³/min Turbine Blower in the Vacuum System for Paper Machines

Introduction

The application of turbine blower replacing the traditional vacuum equipment for paper machines realizes the thorough separation of white water in wire part and white water in press section. In the working condition, it does not need sealing water, so there is a remarkable effect of water conservation and under the same circumstance, its motor capacity is lower for an effect of energy conservation. While the running speed of its impeller is very high, so it needs higher precision in manufacture and installation.

As different processing methods of impeller machining has great influence on the performance parameters of accuracy and surface quality. GooDSeaA adopts complex components processed under five-axis NC machine tools which has a significant improvement on the efficiency and a low technological complexity. GooDSeaA studies geometry characteristic and processing technology of the impeller, analyzes machining technological difficulties and technical requirements of the impeller. Different from the conventional rough and finish machining process of the impeller, the machining of the impeller are classified into four working procedure, which are the slot rough machining aimed to cut a large number of blank material, the leaf blade semi-machining aimed to cut out the uniform allowance,the leaf blade finishing and passage finishing.

Turbine fan is a kind of special centrifugal fan, which is generally divided into multi-stage closed centrifugal fan and single-stage open centrifugal fan. They use the multi-stage impeller installed in the shell and diffusion system to form vacuum. With the rotation of the impeller, air enters the hole in the middle of the impeller, and is accelerated and pressurized in the process of radial outward movement. Then the second stage impeller accelerates the air from the first stage, and then to the third stage and the fourth stage, so as to generate vacuum. The air is inhaled from different levels, thus producing different vacuum degrees to meet the needs of the paper machine vacuum system. As shown in Figure 1 is a simple schematic diagram of a multistage turbine.

No matter multi-stage closed fan or single-stage open fan is used as vacuum pump, it has the characteristics of large suction and stable vacuum level. However, when the vacuum is high and the amount of air available for suction is less and less, air reflux and surge often occur. At this time, the heated air after being accelerated flows back to the suction port, and the intake pipe will be heated, which will seriously damage the stability of the vacuum degree. Therefore, the inlet of each turbine is equipped with anti surge valve. When the vacuum degree is high and the suction capacity is insufficient, the anti surge valve will automatically open according to the effective power of the turbine, and increase the air flow to prevent the occurrence of surge, so as to make the equipment power consumption and the required vacuum degree stable.

Process Flow Diagram of Using the Turbine

Generally, a multistage turbine and two single-stage turbines are used in parallel. Each part of the paper machine that needs the same vacuum degree is connected to one or more concrete gas-water separation tanks. Figure 2 is the basic flow diagram of using the turbine.

The advantages of centrifugal vacuum pump compared with water ring pump

Values Made for Customers

Provide customized design according to user’s paper machine vacuum system, enables the equipment always working in energy-efficiency area, which can save 30-60% energy and 100% water for the papermaking vacuum system. Through the waste heat recovery system, the level of comprehensive energy utilization will be further improved. The investment recovery period is 8-18 months. One unit 500kW centrifugal vacuum pump can at least completely replace the water ring vacuum pump with a total power of 710kW. Each production line can save 200 Thousand Dollars in electricity for cusomters per year.

Saving money means making money. After adopting our company's vacuum pump instead of it’s old water ring pump, one listed papermaking enterprise realized energy saving of 50% and increased production by 20% under the condition that other parts of the paper machine remained unchanged. Our vacuum pump has create the value of 20 Million Dollars every year for this papermaking company.

No need for grid expansion and space saving. With frequency conversion starting, and there is no impact on the power network. Compared with traditional vacuum systems, this equipment saves more than half of space.

Parameters of High-Speed VF Centrifugal Vacuum Pump