Product Introduction

Coke oven waste heat boilers utilize the large amount of 550-950°C waste heat from the rear of coke ovens in the coking industry, or the combustion heat of supplementary coke oven gas, to generate superheated steam for use in condensing steam turbine generators or for industrial and domestic gas production. Our company has developed a series of coke oven waste heat boilers with supplementary combustion and non-supplementary combustion types, double (single) drum horizontal natural circulation water tube boilers, suitable for this industry. This type of waste heat flue gas has the same characteristics as carbon waste heat flue gas. The supplementary combustion boiler uses a fully automatic coke oven gas burner to achieve efficient combustion. Therefore, in addition to supplementary combustion, this makes many waste heat boilers have the same or similar structure.

This new type of coke oven waste gas waste heat boiler has the advantages of high heat transfer efficiency, in-furnace dust separation, compact and novel structure, low cost, small footprint, high efficiency, environmental protection, and energy saving.

Performance Characteristics

I. Efficient Sealed Design

1. The boiler is designed with a constant temperature membrane water wall on all four sides, and all four passages of the boiler are designed with membrane walls as intermediate partitions. This design completely solves the problem of boiler expansion and sealing. The boiler has a low air leakage coefficient, good insulation, less heat loss, and high thermal efficiency.

2. The design of the double drum convective tube bundle structure eliminates redundant pipes outside the furnace. All pressure-bearing components participate in heat exchange within the furnace, resulting in a simple and reliable design. Simultaneously, the absence of external pipes reduces heat loss, thereby improving boiler efficiency.

3. The use of a membrane wall structure reduces the boiler's thermal inertia, allowing for faster boiler start-up and shutdown, reducing heat loss during these processes, and significantly improving thermal efficiency.

II. Anti-Ash Accumulation Structure Design

1. The boiler adopts a vertical four-pass inverted "M" arrangement, with flue gas entering and exiting from the bottom. The convective tube bundles and economizers, which are prone to ash accumulation, are designed with flue gas entering from the top and exiting from the bottom. This allows the flue gas to flow in the direction of gravity, facilitating self-cleaning.

2. In the first pass, the superheater uses a large-pitch longitudinal arrangement of smooth tubes, which is not prone to ash accumulation.

3. In the second pass (convective tube bundle), the flue gas flows downwards in the direction of gravity, and all smooth tubes are arranged longitudinally. Four flue gas baffles are used in the middle of the convective tube bundle to force flue gas flow disturbance, increase flue gas velocity, enhance self-cleaning, reduce ash accumulation, and improve the heat transfer coefficient of the convective tube bundle.

4. The third pass is an all-membrane water-cooled wall channel, where the flue gas flows upwards, acting as a settling chamber to effectively prevent ash accumulation in the tail economizer.

5. The fourth pass (economizer) has a low flue gas temperature and high ash concentration, making it the most prone to ash accumulation. The economizer is arranged in three stages, each independent, with a height of 1.2 meters. Inspection passages are provided between each stage, along with soot blowers, facilitating inspection, cleaning, and maintenance.

6. The economizer serpentine tubes use H-type straight finned tubes arranged longitudinally, which are not prone to ash accumulation; the flue gas flows downwards in the direction of gravity, providing a self-cleaning effect for the economizer.

III. Boiler Load Adaptability Design

1. The constant temperature membrane water wall structure ensures stability and makes the boiler unaffected by flue gas temperature fluctuations.

2. The double drum convective tube bundle design increases the convective evaporation heating surface area. The four-pass membrane water wall furnace wall design also serves as a boiler evaporation heating surface. This combination maximizes the boiler's evaporation capacity at low loads and lowers flue gas temperature.

3. The arrangement of three rows of slag tubes and a membrane water-cooled channel at the front of the superheater ensures safe operation under 50-120% load conditions.

4. The multi-stage arrangement of the economizer allows for independent operation of each stage, fully meeting the operating conditions of boiler load fluctuations.

IV. Superheater Safety Protection

1. Three rows of slag tube bundles and a membrane water-cooled wall channel are arranged in front of the superheater. Utilizing the characteristics of high temperature difference and strong heat absorption, it plays a role in cooling and slag protection for the superheater.

2. The upper steam drum incorporates a cyclone separator, a corrugated plate separator, and a wire mesh, providing three stages of steam-water separation. This ensures the quality of the steam entering the superheater and prevents tube rupture due to salt deposition.

3. The superheater has a 20% surplus heating surface area. Intermediate water spraying for temperature reduction provides a large temperature adjustment range and sensitive regulation, ensuring the stability of the superheater temperature during flue gas temperature fluctuations.

4. The superheater adopts external water-cooled hanging, preventing the risk of traditional dry hangers burning and carbonizing in high-temperature flue gas, significantly reducing superheater maintenance time.

V. Low Boiler Civil Engineering Costs

1. The boiler adopts an all-steel floor-standing structure with eight columns. Users only need to build eight piles at the zero elevation and weld the embedded steel plates, resulting in very low civil engineering costs.

2. The vertical arrangement of the boiler reduces its footprint.

VI. Low Boiler Masonry Costs

The fully sealed membrane wall structure and four-pass partition wall design save more than 60% of refractory materials, reducing boiler masonry costs by 60-70%.

VII. Convenient Boiler Maintenance

Inspection passages and inspection doors are provided before and after the boiler superheater, in the middle of the boiler tube bundle, and before and after the economizer, allowing for maintenance of all heating surfaces.

VIII. Low Boiler Body Resistance

The four-pass, variable cross-section, and constant velocity structure design results in a boiler body resistance of less than 1500Pa, saving system power consumption.

Product Parameters