Roots fan dust removal pneumatic conveying system
When using a Roots fan to design a pneumatic ash removal system, it must first ensure that it can complete the expected conveying task, and at the same time, reasonably determine the type and capacity of the equipment used, as well as the problems and design related to it, not just the cost of the equipment. How much, and more importantly, it is necessary to comprehensively consider the impact of the nature of the material on the quality, the amount of transportation, the distance, the route of the transportation, and the ease and cost of operation and management. For example, for certain materials, the conditions of various equipment All are suitable for pneumatic conveyance, but because of the material containing a large amount of moisture, adhesion and other reasons, pneumatic conveyance of Roots fans cannot be used. Even if the mechanical conveyance equipment is expensive, a mechanical conveyance method must be selected. There are also cases when conveying certain materials, for example, when conveying limestone powder to the storage bin in front of a circulating fluidized bed boiler, the power required for pneumatic conveyance using a Roots fan is large. At first glance, the operating cost is high, but From the point of view of system rationality or production technology, it is better to use pneumatic power. In which case, which method and technology should be adopted, the following requirements should be followed:
① The economy is more reasonable. Generally speaking, mechanical transportation is advantageous in the short distance transportation; on the contrary, for the long distance transportation, although the power transmission of the roots fan is used, The system is disadvantageous, but in terms of equipment cost, it is often advantageous to use a pneumatic conveying system. Equipment costs, required power, and operating costs vary greatly depending on the surrounding conditions, so they cannot be compared in general. At the same time, it should be noted that as the conditions of various platform supports and auxiliary equipment are different, the changes are also large. In short, when designing the Roots fan pneumatic ash removal system, it should be based on the specific conditions of the project. After a comprehensive technical and economic comparison, the most suitable conveying system and corresponding equipment should be selected. If the delivery power and delivery distance of the system have been determined, the economy of the system generally depends on the mixed ash-gas mixture ratio.
② From the perspective of equipment energy consumption, the power required by the pressure (pumping) equipment is proportional to the product of system pressure and air flow. If the mixing ratio of ash and gas is increased, the amount of air to be transported can be reduced. Under the condition that the conveying speed is kept constant, the amount of air to be conveyed is proportional to the square of the pipe diameter, that is, Q∝D2 and the system pressure is the Resistance is inversely proportional to the tube's internal diameter, that is, P∝1 / D and the ratio of gray to gas does not increase in a proportional relationship. Therefore, increasing the ratio of gray and gas conveyed, reducing the amount of air, and reducing the energy of the pressure (pumping) equipment Consumption is very favorable
③ Secondly, from the perspective of the system infrastructure costs, the internal diameter of equipment and pipelines, supports and installation costs can be reduced accordingly due to the increase in the gas-air ratio, and the effect of reducing the system infrastructure costs is also obvious. The larger the gas-air ratio μ is, the more advantageous it is for increasing the conveying capacity, and it will obviously improve the economy. However, if the dust-to-gas ratio is too large, clogging may occur at the same air velocity and the conveying pressure will increase. For negative pressure and low positive pressure pneumatic conveying systems, it may exceed the suction pressure allowed by the pressure machine or Exhaust pressure. Therefore, the value of the ash-gas ratio is limited by factors such as the physical properties of the material, the transportation method, and the transportation conditions. Especially for the positive pressure Roots blower pneumatic conveying system, considering the size and structure of the silo pump itself, the inner diameter and length of the conveying pipe, the number of elbows, and the amount of air used, the ash gas is more restricted than nature.
Contact Sanniu Roots Fan
Name: Shandong Sanniu Machinery Co., Ltd.
Customer Service: 0531-83826888
Address: North Industrial Park, Xianggongzhuang Town, Zhangqiu City