Circulating Fluidized Bed Boiler: A Clean and Efficient Solution for Power Generation

Introduction

A circulating fluidized bed boiler (CFB boiler) is a type of boiler that uses a fluidized bed of solid particles (usually coal, biomass, or waste) as the main combustion fuel. The fluidized bed is formed by injecting air from the bottom of the boiler, creating a turbulent and high-temperature environment where the fuel particles are rapidly mixed and burned. The flue gas from the combustion then passes through a cyclone separator, where the unburned fuel particles are captured and returned to the bed, forming a closed-loop circulation. This process enhances the combustion efficiency, reduces the fuel consumption, and lowers the emissions of pollutants such as nitrogen oxides (NOx), sulfur dioxide (SO2), and particulate matter (PM).

Circulating fluidized bed boiler boilers are widely used for power generation, especially in countries with abundant coal or biomass resources, such as China, India, Indonesia, South Africa, and Brazil.

Part 1:ZOZEN Boiler’s CFB Boilers

ZOZEN Boiler is a leading manufacturer and supplier of circulating fluidized bed boiler boilers in China, with over 30 years of experience and expertise in boiler design, production, installation, and service. ZOZEN Boiler’s CFB boilers have the following features:

1.1 The circulating fluidized bed boiler has a wide range of load regulation and fast load regulation:

When the load changes, it only needs to adjust the coal quantity, air quantity, and material circulation quantity. It can operate steadily at 30% load state, and the thermal efficiency remains basically unchanged. The load regulation ratio of the circulating fluidized bed boiler can reach (3~4):1, and the load regulation rate can reach 5% per minute.Fuel adaptability is wide, with high combustion efficiency:

1.2 It can burn high-quality coal, biomass, as well as various low-quality fuels that chain furnaces cannot burn, such as coal gangue, garbage, sludge, etc. The gas-solid mixture is well mixed, with a high combustion rate. The fly ash is recycled and burned again. The combustible content in the boiler slag is ≤2%, and the combustible content in the fly ash is ≤8%

1.3 Low NOx emissions:

First, through staged air supply and low-temperature combustion; second, through segmented combustion, the conversion of nitrogen in the fuel into NOx is suppressed, and some of the already generated NOx is reduced. The NOx emission value of the boiler is reduced to 100mg/m3.

1.4 Efficient desulfurization:

In-furnace limestone desulfurization + external standby wet desulfurization, the boiler SO2 emissions reach below 5mg/m³

1.5 Types and Parameter:

1.DHX series circulating fluidized bed steam boiler

Capacity: 35 – 100 t/h

Operating pressure: 1.25 – 5.3 MPa

Operating temperature: 194 – 485℃

Applicable fuels: coal, gangue, biomass, sludge

Application industries: chemical industry, power generation, nonferrous metallurgy, papermaking, rubber tires, centralized heating

2.SHX series circulating fluidized bed hot water boiler

Capacity: 7 – 58 MW

Operating pressure: 1 – 1.6 MPa

Operating temperature: 130/70℃, 115/70℃

Applicable fuels: coal, gangue, biomass, sludge

Application Industry: Heating

3.SHX series circulating fluidized bed steam boiler

Capacity: 10 – 100 t/h

Working pressure: 1.25 – 2.5 MPa

Working temperature: 194 – 225℃

Applicable fuels: coal, gangue, biomass, sludge

Application industries: heating, chemical, food, tobacco, textile, printing and dyeing, feed, pharmaceutical, building materials, brewing, rubber, hospitals

4.QXX series circulating fluidized bed hot water boiler

Capacity: 58 – 116 MW

Operating pressure: 1.25 – 1.6 MPa

Operating temperature: 150/130℃, 90/70℃

Applicable fuel: coal, gangue, biomass, sludge

Application industries:Concentrated Heating

Part 2:ZOZEN’s Case

ZOZEN Boiler has successfully delivered and installed CFB boilers for many customers in different industries and regions, such as:

1. SHX Circulating Fluidized Bed Boiler Project by Biotechnology

The ZOZEN SHX series circulating fluidized bed boiler is a type of low-temperature combustion boiler that directly desulfurizes during the combustion process, with high desulfurization efficiency. This series of boilers uses ZOZEN Boiler’s newly developed high-temperature cyclone separator, which is highly efficient and wear-resistant. It is equipped with an advanced air preheater to reduce flue gas temperature and increase the furnace inlet air temperature, effectively improving the overall thermal efficiency of the boiler.

At the same time, the boiler’s large furnace and low flow rate design prolong the residence time of fuel in the furnace, ensuring thorough combustion and saving a significant amount of fuel costs for the enterprise. In addition, the unique wind chamber design provides users with the option of bed ignition and under-bed ignition, meeting different needs of the enterprise.

2. DHX Series 40-ton Biomass Circulating Fluidized Bed Boiler Project for Building Materials Company

In the building materials industry, energy conservation and environmental protection are issues of widespread concern to users. Circulating fluidized bed combustion technology, as a new and matured efficient and low-pollution clean combustion technology, has many advantages that other combustion methods do not have. ZOZEN’s DHX series biomass-fired boilers, with low-temperature combustion control technology, combined with simple dust removal and denitrification technology, can meet the requirements of ultra-low emissions at a low cost, with nitrogen oxide emissions below 100mg/Nm³, helping enterprises achieve green production.

Conclusion

Circulating fluidized bed boilers are a clean and efficient solution for power generation, as they can burn a wide range of fuels, achieve low emissions, and operate at lower temperatures and pressures. ZOZEN Boiler is a leading manufacturer and supplier of CFB boilers in China, offering high-quality, high-efficiency, and eco-friendly products and services. ZOZEN Boiler’s CFB boilers have been widely used in various industries and regions, and have received positive feedback from customers. If you are interested in ZOZEN Boiler’s CFB boilers, please contact us for more information and quotation.