Active, high surface area calcium hydroxide desulfurization (powder) technology performs desulfurization absorption and product treatment in a dry state. This method boasts advantages such as no wastewater or waste acid discharge, reduced equipment corrosion, no significant temperature drop during flue gas 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, 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 route using sodium bicarbonate as the alkali source has rapidly expanded its market share due to its high desulfurization efficiency, broad source 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 substance 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 increased by the power plants, hot blast stoves, and heating furnaces of steel enterprises, as well as glass and cement kilns. Some companies rent land to build storage warehouses for disposal, while others sell it to qualified institutions for processing, with costs ranging from 300 to 500 yuan per ton, thereby increasing the burden on businesses.

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

Tianjin Huaneng Langtian Environmental Protection Equipment Co., Ltd. After four years of breakthrough efforts by our R&D team, we have successfully developed high surface area calcium hydroxide with a surface area (BET) exceeding 45 m2/g. By independently developing core equipment and creating a new production process, we have achieved large-scale production. Our Tianjin production base has a 100,000-ton capacity, offering products with excellent performance!

With our company's developed HNPS desulfurization system, more than 30 units have been industrially applied with excellent operational data, low costs, and satisfied customers. Currently, the system has been successfully applied in coke oven pusher ground stations, dry quenching coke dust removal, coke oven flue gas, steel heating furnaces, hot blast stoves, power plant boilers, and waste incineration industrial 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 desulfurizing agent specifications

Section 4: High-activity, high-specific surface area calcium hydroxide - Recommended usage conditions

Section 5: High Activity, High Specific Surface Area Calcium Hydroxide Characteristics

Highly active and high specific surface area calcium hydroxide boasts characteristics 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 it is widely recognized as an excellent dry desulfurization product internationally. Dry desulfurization agents used in practice are mainly high specific surface area calcium hydroxide and baking soda. Baking soda has a fast reaction rate but is relatively expensive and difficult to dispose of as solid waste. By the 1980s, high specific 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 specific surface area calcium hydroxide has well-developed pores, allowing for rapid adsorption and absorption of HCl and SO2 from flue gas, with a utilization rate exceeding 85%.

Section 6: Introduction to HNPS Dry Desulfurization Process

High-activity, high-surface-area calcium hydroxide dry powder desulfurizer, directly sprayed into the flue gas duct through air conveying, quickly disperses into the flue gas under the action of an efficient jetting device, adsorbs and absorbs most of the acidic media such as F-, Cl-, SO2, and SO3 in the flue gas, and then 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: Large capacity powder storage silos, radar and anti-rotation level sensors, safety valves, vibration motors, arch-breaking auxiliary air disks, and other accessories.

2. Feeding System: Utilizes a high-precision rotating feeder, measured through frequency conversion by 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 screens displaying levels, feed hopper operation frequency, and other key operating states or parameters. The system is equipped with high and low level alarms, level display, and status and fault alarms for the Roots blower.

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

1. Meets ultra-low emission requirements with high desulfurization efficiency; SO2 concentration in the exhaust can reach zero-discharge levels; flue gas SO2 concentration ranges from 40 to 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 by an efficient jet, completing the absorption reaction 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, no additional personnel required, compact equipment footprint, especially suitable for low-temperature, low-sulfur environments.

7. Substitute the baking soda process with a cost-effective, low-energy consumption alternative, addressing solid waste issues.

Section 9: Typical Performance across Industries

   Coking Industry - Coke Pushing Ground StationShougang Qian'an Sinochem Coal Chemical Co., Ltd. No.1, No.2, and No.3 coke ovens - Pushing coke ground dust removal - 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. Coking 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 Power Plants & Power Station Boilers - High-Activity, High-Surface-Area Calcium Hydroxide Desulfurization