Active, high specific surface area calcium hydroxide desulfurization (powder) technology carries out desulfurization absorption and product treatment in a dry state. This method offers advantages such as no wastewater or waste acid discharge, reduced equipment corrosion, no significant cooling of flue gas during purification, high flue gas temperature after purification, favorable for chimney exhaust diffusion, and minimal secondary pollution. It is suitable for flue gas desulfurization technology in industries such as steel, coking, cement, glass, and ceramics.

I. Desulfurization Technology Introduction

In recent years, dry desulfurization technology for flue gas has seen increasing application in small and medium-sized flue gas desulfurization systems, with mature technology and stable operation. The SDS desulfurization process route using sodium bicarbonate as the alkali source has rapidly expanded its market share due to its high desulfurization efficiency, wide availability of desulfurizing agents, and low difficulty in engineering implementation.

As the number of equipment increases, the drawbacks of this technical route begin to show, and how to handle desulfurization ash has become a new environmental challenge. Sodium-based desulfurization ash is a mixture of sodium sulfate, sodium sulfite, and sodium carbonate..The material has excellent water solubility and is classified as general solid waste that is difficult to dispose of in compliance with regulations. According to authoritative statistics, the coking industry alone produces up to 300,000 tons of sodium-based desulfurization ash each year. This figure is further increased by the power plants, hot air furnaces, and heating furnaces of steel companies, as well as glass and cement kilns. Some companies rent spaces to build storage warehouses for storage, while others sell it to qualified institutions for disposal, with costs varying from 300 to 500 yuan per ton, adding to the burden on businesses.

The revised "Environmental Protection Law of the People's Republic of China on Solid Wastes" came into effect on September 1, 2020, introducing new responsibilities for enterprises generating solid waste and imposing severe penalties on illegal activities. The pressure on businesses has surged!

Tianjin Huaneng Langtian Environmental Protection Equipment Co., Ltd. After four years of dedicated research and development, with the efforts of our technical team, we have successfully developed calcium hydroxide with a high specific surface area, achieving a surface area (BET) of over 45 m2/g. Through independently developed core equipment, we have created a new production process, enabling mass production. Our Tianjin production base has a capacity of 100,000 tons, offering superior product performance!

With our company's developed HNPS desulfurization package, over 30 units have been industrialized in use, demonstrating good operational data, low costs, and satisfied customers. Currently, it has been successfully applied in industrial applications such as coke oven push ground stations, dry coke quenching dust removal, coke oven flue gas, steelmaking furnace, hot blast furnace, power plant boilers, and waste incineration kilns, achieving ultra-low emission desulfurization.

High-activity, high-specific-surface-area calcium hydroxide - microscopic crystal structure under electron microscope

Section 3: High-activity, high-specific-surface-area calcium hydroxide desulfurization agent specifications

Four. Reference conditions for high-activity, high-surface-area calcium hydroxide

V. High-activity, high-specific-surface-area calcium hydroxide characteristics

Highly active, high surface area calcium hydroxide boasts characteristics such as porosity, high activity, good dispersibility, and high utilization. Its specific surface area is 3-4 times that of regular calcium hydroxide and is widely recognized internationally as an excellent dry desulfurization product. The main dry desulfurization agents in practice are high surface area calcium hydroxide and baking soda. Baking soda has a rapid reaction rate but is relatively expensive and difficult to dispose of as solid waste. In the 1980s, high surface area calcium hydroxide was widely used in waste-to-energy and thermal power plants in Europe, America, and Japan, successfully replacing baking soda. High surface area calcium hydroxide has well-developed pores, enabling rapid adsorption and absorption of HCl and SO2 from flue gas, achieving a utilization rate of over 85%.

Section 6: Introduction to HNPS Dry Desulfurization Process

Highly active, high surface area calcium hydroxide dry powder desulfurizer, directly sprayed into the flue gas duct via air flow, rapidly dispersing into the flue gas under the action of an efficient jet, adsorbing and absorbing most of the acidic media such as F-, Cl-, SO2, and SO3, and then entering the bag filter along with the flue gas. A small portion of the acidic media continues to react in the bag filter, and the烟气 after desulfurization is directly discharged through the induced draft fan.

This process is unaffected by the temperature of the smoke, and can effectively react at room temperature and above.

Section 7: Features of High-Activity, High-Surface-Area Calcium Hydroxide Desulfurization System

1. Storage System: Equipped with large-capacity powder storage silos, radar and anti-rotation level indicators, safety valves, vibration motors, arch-breaking assist flow air disks, and other accessories.

2. Feeding System: Utilizes a high-precision rotary feeder for material delivery, with frequency conversion and measurement via sensors.

3. Power System: Positive pressure conveying with Roots blower or compressed air, one in use and one in reserve.

4. Control System: Centralized control in the control room, featuring computer screen displays of material level, feeder operating frequency, and other key operational states or parameters. The system is equipped with high and low material level alarms, material level display, status and fault alarms for the Roots blower.

Section 8: Characteristics of Dry Desulfurization with High-activity, High-Surface-areal Calcium Hydroxide

1. Meets ultra-low emissions standards with high desulfurization efficiency; export SO2 concentration can reach near-zero emission levels; flue gas SO2 concentration ranges between 40-300 mg/Nm3, particularly cost-effective.

2. Wide temperature window, with flue gas treatment at 30-350°C, achieving high desulfurization efficiency.

3. The process is simple, utilizing an efficient jet to directly spray ultra-fine powder into the flue, completing the absorption reaction as the flue gas flows.

4. Retrofit or install new bag dust collectors to ensure the system meets ultra-low dust emission requirements.

5. By-products are general solid waste, specifically saturated waste desulfurizing agent, mainly composed of CaSO4, Ca(OH)2, and CaCO3.

6. Centralized control room operation without increasing personnel, with minimal equipment footprint, especially suitable for low-temperature, low-sulfur environments.

7. Replacing the baking soda process with an alternative, saving investment and reducing energy consumption, and addressing solid waste issues.

Section 9: Typical Performance in Various Industries

   Coking Industry - Pushing Coal Tar StationShougang Qian'an Sinochem Coal Chemical Co., Ltd.'s No.1, No.2, and No.3 coke ovens - Push coke ground dedusting with high-activity, high-surface-area calcium hydroxide desulfurization, the industrial unit was put into operation on June 8, 2021, with stable data below 10mg/m3.

2. Coke Industry - Dry Quenching Gas and Coke Oven Flue Gas - High Activity, High Specific Surface Area Calcium Hydroxide Desulfurization

3. Iron and Steel Industry - Hot Blast Furnaces, Heating Furnaces - High Activity, High Specific Surface Area Calcium Hydroxide Desulfurization

4. Other Industries - Waste-to-Energy Power Plants and Power Station Boilers - High-activity, High-Surface-Area Calcium Hydroxide Desulfurization