Formulation and method for dust suppression in mining operations post-blasting

Abstract

The present invention relates to a dust suppression formulation for mining operations, particularly for controlling airborne dust generated after blasting activities. The formulation comprises a synergistic blend of sulfosuccinate esters, sulfo esters, ethoxylated surfactants, and sulfonated esters of glycol or poly-glycol. These components are designed to agglomerate dust particles, reduce re-suspension, and provide long-lasting suppression. The formulation is prepared as a liquid concentrate and is diluted with water in ratios of 1:1000 for metal / non-metal mines and 1:1500 for coal mines prior to application. The formulation demonstrates a dust reduction efficacy of at least 90% within 15 minutes of application, with a neutral pH and low surface tension to ensure safety and optimal performance. It is environmentally friendly, non-corrosive to metals, and effective in all weather conditions. The formulation is applied via pressurized or non-pressurized spraying systems on soil and surrounding areas within the blast radius, offering a sustainable solution for dust control in mining environments.

Description

[0001] Title:

[0002] "Formulation and Method for Dust Suppression in Mining Operations PostBlasting"

[0003] Field of the Invention:

[0004] The present invention relates to the field of dust control and suppression, specifically to chemical formulations and methods for mitigating dust emissions generated in mining operations. The invention addresses both haul road dust suppression and dust control in areas surrounding blasting activities. The invention finds application in metal, non-metal, and coal mining industries, enhancing operational safety, environmental compliance, and efficiency.

[0005] Background of the Invention

[0006] Dust generation is a persistent and critical problem in mining operations, particularly during activities such as blasting. The release of fine and superfine dust particles after blasting creates hazardous working conditions, adversely affects air quality, and poses significant health risks to workers and nearby communities. Exposure to airborne dust can cause respiratory illnesses, including silicosis and pneumoconiosis, as well as negatively impact visibility and overall site safety.

[0007] While working in the marketing and development of haul road dust suppression products, we encountered the unique and significant challenge of controlling dust generated after blasting in mining operations. Upon conducting detailed studies of the phenomenon, it became evident that existing products and technologies do not adequately address the distinct requirements of post-blasting dust suppression.

[0008] Key Observations and Challenges Identified

[0009] 1. Limitations of Existing Products for Post-Blasting Dust Suppression:

[0010] o Products developed for haul road dust suppression are often repurposed for blasting dust control. However, the conditionsand dust dynamics in these two scenarios are significantly different. Haul road solutions focus primarily on surface stabilization, while blasting generates airborne dust that requires deeper penetration and moisture retention properties to agglomerate fine and superfine particles.

[0011] Most existing products fail to address the dual requirement of soil penetration and water retention. If a product penetrates the soil effectively, it lacks moisture retention for the necessary 2-3 hours post-blasting. Conversely, products with adequate water-holding capacity fail to penetrate the soil adequately, limiting their effectiveness.

[0012] on Components in Existing Products and Their Drawbacks: Surfactants and Polymers: Both natural and synthetic surfactants and polymers are widely used. However, these compounds primarily form surface films, limiting their ability to penetrate the soil and agglomerate dust particles effectively.

[0013] Hygroscopic Agents (e.g., Calcium Chloride, Magnesium Chloride): While hygroscopic agents are effective in attracting and retaining moisture, they have significant drawbacks:

[0014] ■ Environmental and Health Hazards: Once dried, these salts become airborne and contribute to fine dust, increasing the risk of inhalation-related lung diseases for workers.

[0015] ■ Corrosive Effects: These compounds are highly corrosive to metal equipment and vehicles, particularly in humid conditions.■ Soil Erosion: Prolonged use leads to the erosion of road surfaces and increases the Total Dissolved Solids (TDS) in water runoff, posing environmental challenges.

[0016] o Lignin-Based Products: Sodium lignin sulfonate and similar lignin-based products have been used in various industrial applications, including mining. However, their properties as dispersing agents often worsen the issue in mining operations. When applied to haul roads or blasting areas, they mix with surface soil, increasing soil fineness and exacerbating dust generation under heavy equipment movement.

[0017] 3. Oil-Based Products:

[0018] o Oil-based dust suppressants can cause surface slipperiness, leading to unsafe conditions for vehicles on haul roads.

[0019] o Petroleum-based oils are poorly biodegradable and can contaminate soil and water resources when emulsions break. o Burnt oils introduce non-biodegradable impurities and carbonaceous residues into the environment.

[0020] 4. Patent Reference Gaps:

[0021] o Patent No. CN102942428A discloses a high-power water gel explosive for coal mines but does not address post-blasting dust suppression. While this patent focuses on explosion applications, it lacks solutions for controlling the fine dust particles generated during and after blasting.

[0022] Need for a Specialized Solution

[0023] From the above observations, it is evident that no prior art adequately resolves the specific challenges of dust suppression after blasting. Existing solutions focus on different scenarios, such as haul road stabilization, butfail to meet the unique requirements of post-blasting dust suppression. These requirements include:

[0024] • Deep Soil Penetration: To bind dust particles at the source and prevent their dispersal into the atmosphere.

[0025] • Long-Lasting Moisture Retention: To maintain a dust-free environment for 2-3 hours post-blasting.

[0026] • Non-Corrosive and Environmentally Friendly Formulation: To avoid damage to equipment and minimize ecological impact.

[0027] Contribution of the Present Invention

[0028] The present invention introduces an innovative solution specifically designed to address the challenges of dust suppression after blasting. Unlike prior art, this formulation combines advanced properties for both deep soil penetration and extended water retention. It effectively binds fine and superfine dust particles, preventing them from becoming airborne and significantly reducing dust hazards in mining operations. The invention is environmentally friendly, non-corrosive, and adaptable to the unique conditions of post-blasting dust dynamics, filling a critical gap in existing technologies.

[0029] Objectives of the Invention

[0030] The primary objective of the invention is to create a cleaner and greener environment in mining areas and their surroundings, including regions where human populations, animals, or wildlife sanctuaries are located nearby. This invention aims to mitigate the environmental and health hazards associated with dust generation after blasting activities in mines. The specific objectives of the invention are as follows:

[0031] 1. Reduction of Dust Hazards Post-BlastingTo develop a dust suppression solution that effectively reduces airborne dust generated during and after blasting operations in mining areas.

[0032] To prevent fine and superfine dust particles from becoming airborne and traveling long distances, thereby reducing air pollution and minimizing the impact on nearby populations, wildlife, and surrounding ecosystems.

[0033] ed Soil Penetration and Agglomeration of Dust Particles To design a formulation with superior penetration properties that allows the product to reach deeper soil layers, ensuring that fine dust particles are bound effectively at the source. To ensure that the solution agglomerates fine and superfine particles, preventing their dispersal into the air during high-energy blasting activities.

[0034] ed Moisture Retention for Effective Dust Control

[0035] To provide a product with excellent water-holding capacity that retains moisture for 2-3 hours post-application in ambient conditions, ensuring long-lasting dust suppression in mining operations.

[0036] To maintain a stable and moist surface layer, preventing the re-release of dust even under heavy mechanical loads or high wind conditions.

[0037] izing Health Risks for Workers and Local Communities To reduce the inhalation of airborne dust particles, which are known to cause severe respiratory diseases, including silicosis and pneumoconiosis, among mine workers and nearby residents.

[0038] To improve visibility and air quality in mining areas, creating a safer and healthier working environment.5. Non-Corrosive and Environmentally Friendly Formulation

[0039] o To ensure that the product is non-corrosive to mining equipment and vehicles, thereby reducing maintenance costs and improving operational efficiency.

[0040] o To develop an eco-friendly formulation that is biodegradable and does not harm surrounding flora, fauna, or water bodies. o To avoid the use of chloride-based, petroleum -based, or burnt oil products, which have detrimental effects on soil, water, and air quality.

[0041] 6. Adaptability to Different Mining Conditions

[0042] o To create a solution that is versatile and effective across various types of mines, including coal, metal, and non-metal mining operations.

[0043] o To ensure that the product performs well under varying environmental conditions, such as different soil types, moisture levels, and climatic factors.

[0044] 7. Reduction of Environmental Impact in Sensitive Areas

[0045] o To specifically address the challenges of mining operations in or near sensitive ecological zones, such as forests, wildlife sanctuaries, and residential areas.

[0046] o To minimize the migration of airborne dust to nearby areas, protecting wildlife and preserving the natural ecosystem. 8. Economic Feasibility and Ease of Application

[0047] o To provide a cost-effective solution that can be widely adopted by the mining industry without significant financial burdens.

[0048] o To ensure that the product can be easily applied using standard spraying systems or other commonly available equipment, making it user-friendly and efficient.9. Compliance with Regulatory Standards

[0049] o To meet or exceed environmental and occupational health and safety regulations for dust control in mining operations.

[0050] o To support mining companies in achieving sustainability goals and maintaining compliance with government and environmental protection agencies.

[0051] By achieving these objectives, the invention aims to revolutionize dust suppression in mining operations after the blasting, offering a sustainable, effective, and environmentally responsible solution to one of the industry’s most pressing challenges.

[0052] Summary of the Invention:

[0053] The invention addresses the problem of dust pollution generated during blasting operations in mining activities. This dust pollution adversely impacts the surrounding environment, nearby populations, workers, animals, and vegetation. Respirable dust particles can travel significant distances under normal atmospheric conditions or windy environments, posing severe health risks, including diseases like silicosis, pneumoconiosis, bronchial asthma, and lung fibrosis. The dust also forms layers on vegetation, obstructing natural processes like photosynthesis. The proposed solution is a water-based surfactant formulation designed specifically for pre-blast applications. The formulation, when sprayed 2-3 hours before blasting, deeply penetrates the soil, maintains moisture, and agglomerates fine and superfine dust particles to prevent them from becoming airborne after blasting. This innovative product effectively minimizes the dispersion of respirable dust into the environment, reducing its harmful effects.

[0054] Key features of the invention include:1. Customized Formulation: Two specific formulations are developed — Dustion PC-BL Coal (dilution ratio 1:1500) for coal mines and Dustion PC-BL (dilution ratio 1:1000) for metal and non- metal mines, tailored to the soil structure and mineralogy of the respective mining environments.

[0055] 2. Enhanced Soil Penetration and Moisture Retention: The formulation’s unique blend of sulfosuccinate esters, alkyl amines, ethoxylates, and sulfonated glycol ensures superior penetration into the soil and extended moisture retention for 2-3 hours.

[0056] 3. Agglomeration of Dust Particles: Fine and superfine dust particles are agglomerated, preventing their dispersion into the air and enabling fast settling.

[0057] 4. Non-Corrosive and Eco-Friendly: The formulation is non-corrosive to equipment and vehicles, non-toxic, biodegradable, and free of hazardous substances like chlorides, phenols, and waste oils.

[0058] 5. Improved Application Method: The product is applied using pressurized or non-pressurized spray systems around the blast hole area, covering the affected radius and additional buffer zones, ensuring comprehensive dust suppression.

[0059] Physical-chemical tests and field trials confirm the product’s superior performance compared to existing solutions. It demonstrates exceptional wetting, penetration, and stability properties, making it an effective and environmentally friendly solution for managing dust pollution in mining operations.

[0060] Detailed description of the invention

[0061] Before explaining the present invention in detail, it is to be understood that the invention is not limited in its application to the details of the construction and arrangement of parts illustrated in the accompanyingdrawings. The invention is capable of other embodiments, as depicted in different figures as described above and of being practiced or carried out in a variety of ways. It is to be understood that the phraseology and terminology employed herein is for the purpose of description and not of limitation.

[0062] The present invention aims to address the challenges of dust suppression in mining operations, particularly in the aftermath of blasting activities. Blasting operations generate significant amounts of airborne dust, which is hazardous to both the environment and human health. Based on extensive studies and field trials, it was concluded that a highly effective dust control agent must possess the ability to penetrate deeply into the soil, agglomerate fine dust particles, and prevent their re-suspension into the air. This is essential for reducing respirable dust that poses health risks and ensuring the stability of the mining environment.

[0063] In the course of research, several surfactants and their miscibility were tested to create a uniform formulation. The formulation includes the following key components, which have been chosen for their ability to work synergistically:

[0064] 1. Sulfosuccinate Esters of Aliphatic or Aromatic Dibasic Acids or it's anhydride : This component is synthesized by reacting aliphatic or aromatic dibasic acids (or their anhydrides) in either cis or trans form with alcohols (C4-C12, normal or branched chain) to form mono- or diesters. These esters are then sulfonated with a variety of agents, such as sulfuric acid, oleum, sulphur trioxide, chloro sulfonic acid, sodium bi sulphite, Sodium Metabisulphite, or Sulphamic acid under controlled temperature conditions (roomtemperature to 130°C) for 3-10 hours. The resulting product is a highly soluble compound in either ethylene glycol or propylene glycol, making it both effective and environmentally friendly.

[0065] Example: A typical reaction formula might be: R1(COOH)2 + R2OH —> R1CO2R2 (ester formation) R1CO2R2 + Sulfonation Agent R1CO2R2SO3 (sulfonated ester).

[0066] Process Parameters:

[0067] o Temperature: 60°C to 130°C

[0068] o Time: 4-6 hours

[0069] o Stirring RPM: 1000-1400

[0070] 2. Sulfo Aliphatic or aromatic Esters of Dibasic Acids ( or it's and hydriede) and Polyols: Aliphatic or Aromatic Dibasic acids or it's anhydries in cis or trans form are esterified with alkyl alcohols (C4- C14) and polyols (2 to 6 hydroxyl groups) to form polyol-based esters. These esters are then subjected to sulfonation with similar agents as above. The neutralization process uses alkali earth metals such as sodium, potassium, lithium hydroxides, or ethanolamine to obtain a neutral or slightly alkaline pH value (7.5 ± 1).

[0071] Example:

[0072] R1(COOH)2 + R2OH + R3(OH)n R1COOR2 + R3COORn (esterification) R1COOR2 + Sulfonation R1COOR2SO3.

[0073] 3. Ethoxylates of Alkylamines, Alcohols, and Acids: Alkylamines, alcohols, and acids undergo ethoxylation with ethylene oxide (EO) to form surfactants with varying numbers of EO units (n=6 to 18). These ethoxylates are used to enhance the emulsifying and dispersing properties of the dust control agent.Example:

[0074] o Alkylamine ethoxylation:

[0075] RNH2 + (2CH2CH2O) RNH(CH2CH2O)n

[0076] o Alkyl alcohol ethoxylation:

[0077] ROH + (2CH2CH2O) RCOCH2CH2O)n

[0078] 4. Sulfonated Esters of Glycol or Poly-Glycol: Monoethylene glycol and its polymers undergo sulfonation with sulfonating agents like sulfuric acid or chlorosulfonic acid to produce a sulfonated ester. This product is further neutralized with alkali metals or ethanolamine to adjust pH.

[0079] Example:

[0080] (OHCH2CH2OH) + (2CH2CH2O) (OHCH2CH2O)(CH2CH2O)nH (ethoxylation)

[0081] (OHCH2CH2OH)n + Sulfonation (OHCH2CH2OH)nSO3H.Formulation Process and Variations

[0082] The formulation of the final product is carried out in ten different variations, with varying ingredient ratios, mixing conditions, and temperature profiles. The following table outlines the different formulations:

[0083]

[0084] Physico-Chemical Properties of the Final Product

[0085] Through laboratory and field trials, the following physico-chemical properties were established:

[0086]

[0087] &

[0088] &

[0089] &

[0090]

[0091]

[0092] Method of Application

[0093] The dust suppression product is diluted as follows:

[0094] • For metal mines: 1:1000 dilution ratio

[0095] • For coal mines: 1:1500 dilution ratio

[0096] The diluted product is sprayed in the vicinity of the blasting area. To apply, first fill the spray tank 30% with water, then add the dust suppression product (Dustron PC-BL for metal / non-metal mines or Dustron PC-BS Coal for coal mines) according to the dilution ratio. After adding the product, fill the tank with water to the desired volume. The spray is applied around the blasting area, extending 5% beyond the radius of the blasting hole. This ensures that the dust is controlled immediately after the blast, preventing airborne particles from spreading.

[0097] Advantages of the Invention

[0098] • Penetration and Agglomeration: The product can penetrate up to 30 mm into the soil, holding moisture and preventing fine dust

[0099] 15particles from becoming airborne. This significantly reduces dust generation by up to 90%.

[0100] • Prevents Airborne Dust: The agglomeration of fine particles ensures that they do not fly into the air, protecting workers and surrounding communities from inhaling harmful dust.

[0101] • Environmental Protection: The dust suppression prevents the dispersion of fine dust into surrounding wildlife areas and prevents soil and vegetation from being covered in dust, allowing plants to continue absorbing carbon dioxide and releasing oxygen.

[0102] • Health and Safety: By preventing airborne dust, the product reduces the risk of respiratory diseases in nearby populations and protects wildlife and plant life from the adverse effects of dust exposure.

[0103] This invention provides an effective and environmentally friendly solution to the problem of dust suppression in mining operations, particularly after blasting. The formulation and method of application ensure that fine respirable dust is controlled, protecting both human health and the environment.

Claims

Claims1. A dust suppression formulation for mining operations, comprising:• a sulfosuccinate ester synthesized from the reaction of aliphatic or aromatic dibasic acids (or their anhydrides) with C4-C12 alkyl alcohols, followed by sulfonation with a sulfonating agent, wherein the sulfonated ester is solubilized in ethylene glycol or propylene glycol;• a sulfo ester formed by esterifying dibasic acids with alkyl alcohols (C4-C14) and polyols (2 to 6 hydroxyl groups), followed by sulfonation and neutralization with an alkali metal or ethanolamine;• an ethoxylated surfactant, wherein alkylamines, alcohols, and acids undergo ethoxylation with ethylene oxide to form a surfactant with ethylene oxide units in the range of 6 to 18;• a sulfonated ester of glycol or poly-glycol, wherein monoethylene glycol or its polymer undergoes sulfonation and subsequent neutralization with alkali metals or ethanolamine, wherein the formulation is designed to suppress dust generated from mining activities, especially after blasting.

2. The formulation of claim 1, wherein the sulfosuccinate ester comprises 10-40% by weight of the formulation, the sulfo ester comprises 15-55% by weight of the formulation, and the ethoxylated surfactant comprises 5-20% by weight of the formulation.

3. The formulation of claim 1, wherein the sulfonated ester of glycol or poly-glycol comprises 10-30% by weight of the formulation.

4. The formulation of claim 1, wherein the formulation is in the form of a liquid concentrate that is diluted with water at a dilution ratio of 1:1000 for metal / non-metal mines and 1:1500 for coal mines prior to application.

5. The formulation of claim 1, wherein the formulation is capable of reducing airborne dust by at least 90% in the vicinity of a blasting area within 15 minutes of application.

6. The formulation of claim 1, wherein the pH of the final formulation is between 7.0 and 8.0, and the formulation has a surface tension of less than 30 dynes / cm.

7. The formulation of claim 1, wherein the formulation is applied to the soil and surrounding areas within 5% of the blast radius using a pressurized or non-pressurized spray system.

8. A method of suppressing dust in mining operations, comprising the steps of:• providing the dust suppression formulation of claim 1;• diluting the formulation with water to obtain a working solution at a dilution ratio of 1:1000 for metal / non-metal mines or 1:1500 for coal mines;• spraying the diluted solution onto the soil and surrounding areas within 5% of the blast radius of the blasting site, thereby agglomerating and preventing the re-suspension of dust particles into the air.

9. The method of claim 8, wherein the dust suppression formulation is applied using a spray system mounted on vehicles, drones, or stationary installations.

10. The method of claim 8, wherein the formulation is applied immediately after the blasting operation to prevent airborne dust from becoming respirable.

11. The method of claim 8, wherein the dust suppression formulation is applied at an application rate of 20-50 liters per hectare of land surrounding the blasting site.

12. A dust suppression agent, comprising:• a combination of sulfosuccinate esters, sulfo esters, ethoxylates of alkylamines, alcohols, and acids, and sulfonated esters of glycol or poly-glycol;• wherein the combination is formulated to effectively agglomerate and suppress airborne dust generated from mining activities, particularly after blasting, by preventing the re-suspension of dust particles into the air.

13. The dust suppression agent of claim 12, wherein the combination of ingredients results in a product that can penetrate up to 30 mm into the soil and form an agglomerated layer that holds dust particles in place, preventing their re-suspension.

14. The dust suppression agent of claim 12, wherein the formulation is environmentally friendly and does not cause corrosion on metals such as mild steel, copper, bronze, or aluminum.

15. The dust suppression formulation of claim 1, wherein the formulation reduces respirable dust levels in the vicinity of a blasting operation by at least 90% within 15 minutes of application.

16. The dust suppression formulation of claim 1, wherein the formulation is effective in all weather conditions and can be applied during dry, windy, or rainy conditions without significant reduction in effectiveness.

17. A dust suppression formulation, comprising an anionic / non-ionic blend of surfactants, which are derived from sulfosuccinate esters, ethoxylates of alkylamines, alcohols, and acids, and sulfonated esters of glycol or poly-glycol, wherein the formulation is capable of controlling dust generated from mining activities.

18. A method of reducing dust exposure to workers and nearby communities, comprising applying the dust suppression formulation of claim 1 to the vicinity of a blasting site to prevent dust re-suspension into the air, thereby mitigating health risks associated with airborne dust.

19. The method of claim 8, wherein the dust suppression formulation prevents dust dispersion into nearby wildlife areas, thereby protecting local fauna and flora from dust exposure.

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