High-activity calcium-based desulfurizer

The desulfurization technology of active, high surface area calcium hydroxide (powder) is performed in a dry state, with the desulfurization absorption and product treatment processes. This method offers advantages such as no effluent or waste acid discharge, reduced equipment corrosion, no significant cooling of flue gas during purification, high flue gas temperature post-purification, facilitating chimney exhaust diffusion, and minimal secondary pollution. It is suitable for flue gas desulfurization in industries such as steel, coking, cement, glass, and ceramics.

Section 1: 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 project implementation.

As the number of equipment increases, the drawbacks of this technological route begin to surface, 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 substance 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 annually. This figure is further multiplied by the power plants, hot air furnaces, and heating furnaces of steel enterprises, as well as glass kilns, cement kilns, and more. Some companies rent land to build storage warehouses for storage, while others sell it to qualified institutions for disposal, with costs ranging from 300 to 500 yuan per ton, thereby increasing the burden on businesses.

As of September 1, 2020, the revised "Environmental Protection Law of the People's Republic of China on Solid Waste Pollution" came into effect, 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 research and development efforts by our technical staff, we have successfully developed high surface area calcium hydroxide with a specific surface area (BET) exceeding 45 m2/g. Through self-developed core equipment, we have created a new production process, achieving mass production. Our Tianjin production base has a 100,000-ton capacity, and our products offer superior performance!

With the HNPS desulfurization package developed by our company, over 30 sets have been industrially applied with good operational data, low costs, and satisfied customers. Currently, it has been successfully applied for ultra-low emission desulfurization in coke oven push ground stations, dry-cooling coke dust removal, coke oven flue gas, steel heating furnaces, hot blast stoves, power plant boilers, and waste incineration industrial kilns.

High-activity, high-specific-surface-area calcium hydroxide - Microcrystalline structure under electron microscopy

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

Section 4: High-activity, High-Surface Area Calcium Hydroxide - Recommended Usage Conditions

Section 5: High Activity and High Specific Surface Area Calcium Hydroxide Properties

Highly active and high surface area calcium hydroxide boasts features such as porosity, high activity, good dispersibility, and high utilization rates. Its specific surface area is 3-4 times that of ordinary calcium hydroxide and is recognized internationally as an excellent dry desulfurization product. Dry desulfurization agents used in practice primarily include high surface area calcium hydroxide and baking soda. While baking soda reacts quickly, it is relatively expensive and difficult to dispose of solid waste. By the 1980s, high surface area calcium hydroxide had been widely used for desulfurization 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, allowing for rapid adsorption and absorption reactions of HCl and SO2 in flue gas, achieving a utilization rate of over 85%.

Section 6: Introduction to HNPS Dry Desulfurization Process

Highly active and high surface area calcium hydroxide dry powder desulfurizing agent, directly sprayed into the flue gas duct via air conveying. Under the action of the high-efficiency jetting device, the calcium hydroxide powder rapidly disperses into the flue gas, adsorbs and absorbs most of the acidic media such as F-, Cl-, SO2, and SO3, and enters the bag filter with the flue gas. A small portion of the acidic media continues to react in the bag filter, and the flue gas after desulfurization is directly discharged through the induced draft fan.

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

Section 7: Characteristics of High-activity, High-Surface-Area Calcium Hydroxide Desulfurization System

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

2. Feeding System: Equipped with a high-precision rotary feeder, the system measures through frequency conversion using sensors.

3. Power System: Roots blower or compressed air positive pressure conveying, one in operation and one in standby.

4. Control System: Centralized control in the control room, with computer screen displaying main operating states or parameters such as material level and feeder operation frequency. The system is equipped with high and low material level alarms, material level display, status of the Roots blower operation, and fault alarms.

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

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

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

3. The process is simple, with the ultra-fine powder directly sprayed into the flue gas duct through an efficient jet, where absorption and reaction are completed during the flow of flue gas.

4. Ensure the existing or newly added bag dust collector meets the ultra-low dust emission requirements of the system.

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

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

7. Replacing the baking soda process with a substitute, saving investment and reducing energy consumption, and solving solid waste issues.

Section 9: Typical Performance across Various Industries

   Coking Industry - Pushing焦 StationShougang Qian'an Sinochem Coal Chemical Co., Ltd. No.1, No.2, and No.3 coke ovens - coke pushing and dust removal system with high-activity, high-specific surface area calcium hydroxide desulfurization. The industrial unit was put into operation on June 8, 2021, with stable data below 10mg/m3.

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

3. Steel Industry - Hot Blast Furnace, Heating Furnace - High-activity, High-Surface Area Calcium Hydroxide Desulfurization

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