Active, high surface area calcium hydroxide desulfurization (powder) technology performs desulfurization absorption and product treatment under dry conditions. This method boasts advantages such as no wastewater or waste acid discharge, reduced equipment corrosion, no significant cooling of flue gas during purification, high flue gas temperature post-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.

Section 1: Desulfurization Technology Introduction

In recent years, the 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. Among them, the SDS desulfurization process using sodium bicarbonate as the alkali source has rapidly expanded its market share due to its high desulfurization efficiency, wide source of desulfurizing agents, and low difficulty in project implementation.

As the number of equipment increases, the drawbacks of this technological 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..Material has excellent water solubility and falls under general solid waste that is difficult to dispose of in compliance with regulations. Authoritative statistics show that 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 and cement kilns. Some companies rent land to build warehouses for storage, while others sell it to qualified institutions for disposal, with costs varying from 300 to 500 yuan per ton, increasing the burden on businesses.

The revised "Law of the People's Republic of China on the Prevention and Control of Environmental Pollution by Solid Wastes" took effect on September 1, 2020, introducing new responsibilities for enterprises generating solid waste and strictly penalizing 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 team, we have successfully developed calcium hydroxide with a high specific surface area, achieving a specific surface area (BET) of over 45 m2/g. Through independently developed core equipment, we have created a new production process, achieving mass production. Our Tianjin production base has a 100,000-ton capacity, offering products with superior performance!

With our company's developed HNPS desulfurization system, over 30 units have been industrially applied with excellent operational data, low costs, and satisfied customers. Currently, the system has been successfully applied in industrial kilns for coking ground stations, dry cooling coke, dust removal in coke oven flue gas, steel heating furnaces, hot blast stoves, 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 microscopy

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

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

V. High Activity and High Specific Surface Area Calcium Hydroxide Properties

Highly active, high surface area calcium hydroxide features porous structure, high activity, good dispersion, and high utilization rate. Its specific surface area is 3-4 times that of ordinary calcium hydroxide, and it is widely recognized as an excellent dry desulfurization product internationally. Dry desulfurization agents in practice are mainly high surface area calcium hydroxide and baking soda. While baking soda has a rapid reaction rate, it is relatively expensive and difficult to dispose of solid waste. By the 1980s, high surface area calcium hydroxide had been widely used in waste-to-energy and thermal power plants for desulfurization in Europe, America, and Japan, successfully replacing baking soda. High surface area calcium hydroxide possesses well-developed pores, allowing for 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 Technology

Highly active, high surface area calcium hydroxide dry powder desulfurizer, directly jetted into the flue gas duct through air conveying, rapidly disperses in the flue gas under the action of an efficient jetting unit, adsorbs and absorbs most of the acidic media such as F-, Cl-, SO2, and SO3 in the flue gas, and enters the bag dust collector along with the flue gas. A small portion of the acidic media continues to react in the bag dust collector, 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: Large-capacity powder storage silos, radar and anti-rotation level sensors, safety valves, vibration motors, arch-breaking auxiliary airflow discs, and other accessories.

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

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

4. Control System: Centralized control in the control room with computer screen displaying main operating states or parameters such as material level, feeder operating frequency, etc. The system includes high and low level alarms, material level indication, and rotor blower operating status and fault alarms.

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

1. Meets ultra-low emission requirements with high desulfurization efficiency; the SO2 concentration at the outlet can reach near-zero emission levels; flue gas SO2 concentration ranges between 40~300mg/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 ultra-fine powder directly sprayed into the flue gas channel through an efficient jet, completing the absorption reaction during the flow of flue gas.

4. Ensure the system meets ultra-low dust emission requirements with either the reuse or addition of bag dust collectors.

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 personnel, with minimal equipment floor space; particularly suitable for low-temperature, low-sulfur environments.

7. Replacing the baking soda process with an alternative, it offers cost savings, low energy consumption, and addresses solid waste issues.

Section 9: Typical Performance in Various Industries

   Coking Industry - Coke Pushing StationShougang Qian'an Sinochem Coal Chemical Co., Ltd. 1st, 2nd, and 3rd coke ovens - Push coke surface dust removal 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. Coke Industry - Dry Quenching Gas and Coke Oven Flue Gas - High-activity, High-Surface-Area Calcium Hydroxide Desulfurization

3. Iron and Steel Industry - Hot Blast Furnaces, Heating Furnaces - 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