Industrial Blasting Materials Technical Guide: Professional Analysis from Explosive Classification to Safe Application

Civil blasting materials, as “the foundation of basic industry and the driver of the energy industry,” play an indispensable role in mining, transportation, hydraulic engineering, urban construction, and other fields. As China’s economy moves into a new normal and the “Belt and Road Initiative” advances, the blasting industry is undergoing a deep transformation from a manufacturing-oriented model to a service-oriented model. This article systematically presents the core technical knowledge of industrial blasting materials to help practitioners gain a deeper understanding of this specialised industry.

I. Essential Characteristics of Civil Blasting Materials

Civil blasting materials refer to explosives, their products, and pyrotechnic articles used for non-military purposes. Compared with ordinary materials, explosives have three fundamental characteristics, which are necessary conditions for explosion:

• Exothermic Nature of Reaction

Explosives can release tremendous heat when detonating. Each 1 kg of explosive releases 1,675 kJ to 6,280 kJ of heat after explosion, with detonation temperatures reaching 1,500 ℃ to 4,500 ℃. The heat released by the reaction is the energy source for the explosive work.

• High Velocity Process

The explosion process is completed instantaneously. For example, 1 kg of TNT completes detonation in only 1×10⁻⁵ s, with common explosives having VOD of approximately 3,000 m/s to 8,500 m/s. High velocity concentrates energy in time and space, which is the key distinction from general combustion. Under the same conditions, the higher the VOD, the greater the destructive power.

• Generation of Large Volumes of Gas

After detonation, 1 kg of common explosive generates 600 L to 1,000 L of gaseous products under standard conditions (0 ℃, 101.325 kPa), with volume expanding several hundred times. The rapid expansion of high-temperature, high-pressure gas produces tremendous destructive forces, with pressures reaching hundreds of thousands of atmospheres (1 atm = 101.325 kPa).

II. Main Types of Modern Industrial Explosives

According to the Chinese Standard WJ/T 9041-2004, industrial explosives are divided into eight categories by professional attributes. Among these, three major water-containing explosives represent the current technological direction:

• Emulsion Explosives

Emulsion explosives use an oil-in-water (or water-in-oil, depending on formulation) emulsion structure with microscopic oxidiser solution droplets as the dispersed phase. Emulsions feature strong water resistance, good safety properties and excellent detonation performance, making them competitive modern industrial explosives. Their density can be adjusted in the range ~1.0–1.3 g/cm³, with detonation velocities typically in the 3,000–5,000 m/s range.

• Water-gel Explosives

Gel-like water-containing explosives made by mixing nitrate as oxidizer, methylamine nitrate as the sensitizer, with combustible agents, gelling agents, cross-linking agents, etc. They exhibit strong water resistance and good plasticity, suitable for blasting operations in wet working faces. Shelf life can reach up to about 270 days.

• ANFO Explosives

Including expanded ammonium nitrate explosives, porous granular ANFO explosives, etc. Expanded ammonium nitrate explosive is a mixed explosives with cap sensitivity, composed mainly of expanded ammonium nitrate mixed with fuel oil and wood flour. This type of explosives has low cost and widely availability of raw materials, making it particularly suitable for on-site bulk charging in large mines.

III. Technological Innovation in Industrial Detonators

Detonators are the core component of initiating systems. In recent years, the emergence of electronic detonators represents the highest level of technological progress in the industry.

• Technical Advantages of Electronic Detonators

Electronic detonators use electronic control modules to control the detonation process. They offer precise control of delay time and initiation energy and normally include built-in identity codes and firing passwords. Delay times can be accurately set within 0–16,000 ms, with errors ≤ ±1.5 ms (when delay time  ≤150 ms).

• Significantly Enhanced Safety Performance

Electronic detonators have greatly improved electrostatic sensitivity, capable of withstanding electrostatic discharge of 500 pF capacitance and 25 kV voltage without explosion. They also have strong resistance to stray currents, capable of withstanding 48 V DC voltage and 220 V AC voltage for 10 seconds without explosion, significantly enhancing safety in complex electromagnetic environments.

IV. Application of Non-Electric Initiating Systems

Shock tube detonator (non-electric initiating systems) is important technologies developed in the 1970s. Shock tubes are rope-like initiating devices that utilize the tube effect of shock wave propagation for low-energy, low-speed shock waves, which can be activated by relatively small detonation or deflagration impacts.

• System Advantages

Non-electric initiating systems are not affected by stray currents, static electricity, or lightning interference, making them safe and reliable for use in modern mines. Shock tubes weigh only 5–6 g per metre, with explosive core containing not exceeding 20 mg/m, saving material and simplifying transport. They have simple structure, production processes easily automated, reliable initiation, and convenient operation.

V. Industry Development Trends and Safety Management

• Directions for Technological Innovation

The civil explosives industry should follow scientific development and technology advancement to develop new products, improve quality, and promote deeper upstream-to-downstream integration. Trends include shifting industrial explosive production from centralized ground production lines to on-site bulk charging operations, moving from packaged products to bulk products, and developing detonators that are higher-precision, higher-reliability, intelligent, and more environmentally friendly.

• Safety Production is Paramount

All civil blasting materials share the characteristic of being easily combustible and explosive. Therefore, personnel involved in the production, distribution and use of civil explosives must prioritize safety above all. Regular participation in safety education and training, familiarity with production safety regulations and operating procedures, and mastery of position-specific safety operation skills are mandatory.

Conclusion

Industrial blasting materials technology is evolving toward higher efficiency, greater safety and improved environmental performance. From traditional TNT-AN explosives to modern emulsion explosives, and from conventional electric detonators to electronic detonators, each technological advance pushes the industry to a higher level. For practitioners, only a deep understanding of professional technology combined with strict compliance with safety regulations can achieve the dual goals of safe production and economic benefit in this special industry.