Overview
China is a major coal-producing country, with coal serving as the primary fuel for electricity generation. In recent years, China's energy industry has seen steady development, with an annual growth rate of electricity generation capacity at 7.3%. The rapid growth of the power industry has led to a sharp increase in fly ash emissions. The total amount of fly ash emitted by coal-fired power plants has been increasing year by year, reaching 125 million tons in 1995, approximately 150 million tons in 2000, and expected to reach 200 million tons by 2010, posing pressure on our national economic construction and ecological environment. In the coal-fired boiler systems of power plants, fly ash emissions can be categorized into dry and wet discharge. Currently, in areas with developed cement industries, dry fly ash is in high demand as a blending material for cement production, and has become a valuable resource. Wet fly ash has similar physical and chemical properties to dry fly ash, but due to its high moisture content (up to 45%), it does not meet the requirements for cement production and is not favored by the market. It is therefore stored in wet ash storage, accumulating and causing severe environmental pollution. With the continuous optimization of national industrial policies and the increasingly stringent environmental protection regulations, the proper disposal of wet fly ash has become a priority. Only by enhancing the comprehensive utilization value of fly ash, drying it with reasonable energy consumption and simple processes to reduce moisture content to below 5%, can we turn waste into treasure and achieve a dual harvest of social and economic benefits.
Wet fly ash boasts distinct characteristics such as high moisture content, low specific gravity, and fine particle size. Traditional drying equipment is ineffective in addressing the drying issue of wet fly ash. When using a conventional drying machine to dry fly ash, due to the three aforementioned characteristics of the material, air tunnels form within the equipment, causing short-circuiting of the hot gas flow, high exhaust gas temperatures, and severe heat loss. The fly ash drying machine developed by Dongding Drying achieves large-scale utilization by rapidly dehydrating high-moisture fly ash, not only solving the problem of fly ash occupying space and polluting the environment but also effectively realizing the reuse of waste resources, thus gaining market favor.
Section 2: Working Principle of Fly Ash Drying Machine
The working principle and features of the fly ash drying machine system: When the hot air temperature in the hot air furnace reaches 350°C, under the indication of the PC system, all equipment begins to operate. The wet material conveying equipment transports wet fly ash with moisture content below 20% into the discharging feeding machine. The discharging feeding machine has both discharging and conveying functions, evenly feeding the material into the belt conveyor, then into the storage bin, and finally into the drying drum through the spiral feeding machine. This equipment is superior to the traditionalTumbler DryerReduce energy consumption by one-third, significantly lowering production costs. This technology is at an advanced level domestically, and its working principle is as follows: Material enters the inner layer of the three-tiered roller from the feeding device, achieving a downstream drying process. Under the scrapers in the inner layer, the material is continuously lifted and scattered in a spiral motion for heat exchange. As it moves to the other end of the inner layer, it enters the middle layer for upstream drying. In the middle layer, the material is repeatedly lifted in a two-step-forward-one-step-back manner, absorbing heat from both the inner and middle roller layers, thus extending the drying time and achieving the dry state. Moving to the other end of the middle layer, the material falls into the outer layer, where it moves in a rectangular multi-loop manner within the outer roller. The material achieving the drying effect is quickly transported out of the roller by the hot air, while wet material that hasn't reached the dry state cannot move quickly due to its weight. Within this rectangular scraper, the material is thoroughly dried, achieving the drying effect and completing the process. Wet fly ash undergoes a thorough heat exchange with the hot gas flow, primarily through convection and heat conduction, with some radiation as well. The three-tiered roller structure benefits the material's residence time inside the equipment, increasing the heat exchange time, enhancing the energy efficiency, and reducing the equipment footprint.
Section 3: Performance Features of Fly Ash Drying Machine
Compact structure, minimal footprint, occupying half the space of a single-tube dryer of the same capacity, reliable operation, low energy consumption, high thermal efficiency. Effective material drying, easy to automate control, and requires fewer operators.
Four,附属设备 for Fly Ash Drying Machine
The equipment includes electromagnetic vibration feeders or disc feeders, bucket elevators, hot air furnaces, transmission systems, vibration screens, conveying equipment, etc. The burners for the hot air furnaces are available in fuel oil, combustion gas, coke, and coal. Among the various types, coal combustion is most common. Users must specify this when placing an order.
Five, YFSH sleeve typeThree-tube dryerMain Technical Parameters: (To be redesigned according to customer requirements)
