Dust Control Technology Research Articles

ОЦІНКА ТЕХНІЧНО ДОСЯЖНОГО РІВНЯ ЗАПИЛЕНОСТІ ПОВІТРЯ ПРИ ВИЇМКОВИХ РОБОТАХ У ВУГІЛЬНИХ ШАХТАХ

Purpose. Development of a criterion for compliance with the normative indicator – technically achievable level of dust (TAL) – a safe dose of dust particles that have entered the lungs of the employee for the entire period of retirement. Method. The research was conducted on the basis of standard algebraic analysis of the requirements of regulatory documents. Results. A criterion was obtained for the assessment by the coordinating organizations of the correctness of the mine’s determination of the technically achievable level of dustiness of the TAL. It is not related to the assessment of the perfection of dust control technology, but to the medical requirements for the prevention of employee pneumoconiosis during the entire retirement age of his work in a dusty atmosphere (20 years). The criterion is based on the amount of dust load on the respiratory organs of the underground worker during the shift, month, year and the entire period of his work, regulated by current regulations. Scientific novelty. It consists in the mathematical formalization of an intuitive connection between TAL – the maximum level of dustiness of underground workings during excavation machines, medium-variable dust, which takes into account interruptions in the work of excavation machines, and dust load on the respiratory organs of the worker. Practical meaning. The developed criterion allows to carry out the coordinated policy of the management and trade unions of the coal enterprises, supervisory and coordinating instances in questions of reasonable sufficiency of the planned antidust measures, both at a stage of drawing up of the design documentation, and at coordination of acts of TAL. Key words: dustiness, dust load, respiratory organs, dust excretion, dust suppression.

Environmentally Friendly Methylcellulose-Based Binders for Active and Passive Dust Control.

Particulate matter (PM) is an essential indicator to evaluate air pollution, threatening human health. Although PM control could be achieved by using a variety of polymeric materials, identifying effective and green materials remains elusive in dust control technology. Here, we have employed environmentally friendly cellulose modified by methyl side groups, such as methylcellulose (MC)-based polymers, and evaluated their PM reduction efficiency when utilized in active and passive dust control methods, such as dust suppressants and air filters, respectively. When 25 m/s wind was applied on soil treated by MC-based polymers, PM emissions were reduced 95% or 85% lower than the soil treated by only water or the other cellulose without methyl side groups. The MC-based polymer was also effectively suppressed mineral dust from a local copper mine in Arizona with approximately 50 times lower amounts than a synthetic polymer containing methyl side groups. Furthermore, when MC-based polymers have deposited on filters of commercial face masks, the average filtration efficiency improved to greater than 99% while maintaining airflow resistance. Our results present that environmentally friendly MC-based polymers can act as dust binders that effectively agglomerate air pollutants, preventing the PM emission from dust sources and the inhalation after being suspended in the air; thus, labeling them as essential materials for advanced active and passive dust control technology.

Preparation and performance evaluation of environment-friendly biological dust suppressant

Enzyme-induced carbonate precipitation (EICP) is an economical and eco-friendly technology. The purpose of this study is to evaluate EICP technology for the control of coal dust pollution in open-pit coal mines. A biological dust suppressant was prepared by using urease extracted from soybean. The optimal proportion of biological dust suppressant was determined and the dust consolidation effect of biological dust suppressant was evaluated. The results show that when the volume ratio of urease and CaCl2-urea solution is 1: 3 and the concentration of CaCl2-urea solution is 0.6 mol/L, the precipitation ratio (PR) (83.83%) in coal dust is the highest. Moreover, the mineralization product is calcite-type CaCO3. In the wind erosion-resistance test, when the angle between the air flow and the sample is 0° and the concentration of CaCl2-urea is 0.6 mol/L, the weight loss of coal dust is 2.56%. The corrosive and toxicological properties of biological dust suppressant show that it is non-toxic, less corrosive and weakly alkaline (pH = 7.70). The above results indicate that EICP is a promising coal dust control technology.

Study on the air curtain dust control technology with a dust purifying fan for fully mechanized mining face

An air curtain dust control technology for a fully mechanized mining face was developed, using a method that combined numerical simulations with field measurements in this paper. The results show that a triangular air curtain was formed between the shearer and the footway by the high velocity airflow field generated at the outlets of two fans after the technology was applied, which can effectively prevent dust from entering the driver's working area. Before the dust control technology was applied, the dust concentration of the shearer driver's working area exceeded 2000 mg/m3. However, after the dust control technology was applied, the dust concentration of the shearer driver's working area was reduced to 300 mg/m3. After verification through field measurements, the dust control rate of each measuring point, apart from the advancing support, exceeded 40%, and that of the shearer driver's working area was over 90%.

Evaluation of Engineering Controls at Bagging Operations to Reduce Exposures to Respirable Crystalline Silica Dust.

The National Institute for Occupational Safety and Health (NIOSH) and the former U.S. Bureau of Mines (USBM) have given a significant effort over the past four decades in researching and developing engineering controls and interventions to reduce mine workers' dust exposures during the bagging and palletizing of industrial minerals. Workers performing manual bagging and palletizing of 50- to 100-pound bags typically have some of the highest dust exposures of all workers at mining and mineral processing operations. This paper will provide an overview of available dust control technologies for bagging operations and present the findings of a recent case study that was conducted at four different industrial sand operations to identify the current types of bagging and palletizing technologies being used and to evaluate their effectiveness in reducing workers' exposures to respirable crystalline silica dust. An evaluation will also be performed to determine if further reductions in respirable dust levels can be achieved by incorporating additional modifications or improvements into the existing technology.

The influence of pore structure of coal on characteristics of dust generation during the process of conical pick cutting

To reveal the influence of pore structure of coal on the characteristics of coal dust generation during roadheader cutting, a self-developed coal cutting system was used to generate dust. A low field nuclear magnetic resonance was utilized to measure the pore system of coal. Results show that the porosity had negative correlations with the cumulative proportions of both respirable dust and fine particulate matter (PM2.5), but the positive influence on the mass ratio of dust generation (MRD) of total dust and slight effect on MRD of respirable dust and PM2.5 were observed. The correlations of the fractal dimension (Df) of pore structure on dust generation were inverse compared with that of porosity. The negative relationship between porosity and Df was the reason for the opposite correlations. This study can provide basic support for the estimate of dust hazard and the development of dust control technologies.

Study and application on foam-water mist integrated dust control technology in fully mechanized excavation face

The dust produced by the roadheader during the tunneling process will change with time. Water mist can achieve high dust removal efficiency when the dust production is relatively small, and foam technology can realize high efficiency in the treatment of large dust production. It is necessary to choose water mist and foam dust removal technology freely according to the dust yield. Therefore, this paper puts forward the research of foam and water mist integrated dust removal technology. According to the characteristics of dust production in excavating operation, a new type of flat fan foam nozzle is put forward. Through the internal channel of gradual change, the foam jet is transformed from a cylindrical fluid to a flat one and diffuses at a certain angle. And the outlet area of the nozzle is determined to be 120mm2, with the nozzle’s uniform angle of 6° and the compression angle of 25° as the final angle of the nozzle through simulation and field experiments. Combined with the characteristics of water mist, the function of water atomization is added to foam technology. On the basis of foam nozzle, 10 symmetrical water inlet channels with a diameter of 1.5mm are uniformly arranged on the side wall, and the original foam inlet is changed into air inlet. Through multi-stage atomization of air and water, water mist with fine atomization size and uniform distribution can be produced. Relevant atomization operation conditions are tested through experiments. The test results show that the new technology could greatly reduce the cost, achieve the goal of efficient dust removal, and guarantee the working environment and the health of the workers.

Exposure effect to cement dust pollution: a mini review

The aim of this paper is to illuminate the impacts of cement production emissions on the environment. Various research work has shown that countries in sub-Saharan Africa, suffer the most from environmental pollution especially air pollution. One of such contributing factors is the behavioural pattern of workers and traders living close to production plants. Significantly also, data are not available in this region. The need for cement as well as the presence of local raw materials, coupled with the need for local content has resulted in an increase in the number of cement plants. Areas within and around the cement plant are exposed to various air pollutants. These pollutants affect the life and wellbeing of workers, children and people in close communities as well as the flora and fauna. Diseases such as chronic obstructive pulmonary, silicosis, preterm delivery, psychasthenia, endocrine disruption, cancer and infertility are associated with these pollutants. This paper describes the impacts of these pollutants on human’s health and plant’s growth as well as where studies should focus on in the future. Various high impact papers were selected and cogent findings as it affects different classes of people were discussed in this paper. It is recommended that more data collection, pollutant characterization, risk assessment and dispersion analysis should be carried out in developing countries. More research should be undertaken to determine the impact of alternative fuel and the effectiveness of dust control technologies used in various cement plants.

Numerical simulation study on dust pollution characteristics and optimal dust control air flow rates during coal mine production

Ventilation and dust removal is the most basic means of dust prevention in mines. In the paper, a highly simulated physical model of the goaf and multiple dust sources were established in order to obtain the optimal dust-removal air flow rate in the roadway. In addition, by combining the numerical simulation method, the influence of the flow rate on dust diffusion rules of the dust sources was analyzed. The research results showed that the mass concentration of the dust in the fully-mechanized working face was gradually decreased with the increase of the air flow rate at a certain range of 700–1600 m3/min. However, high air flow rate can cause the re-entrainment of the dust, contaminating the working environment again. It was confirmed that the optimal dust-removal air flow rate of the inlet air was within a range of 1500–1600 m3/min, which generated the lowest average mass of the dust in the working area suitable for normal operations. This range of air flow rate might be used as a reference in the mine ventilation design in order to provide the coal mine workers with a clean and safe production environment. In addition, the research method and results are of great significance to the formulation and development of effective dust control and dust removal cleaner production technology, and can be used as a reference for the ventilation design in underground projects such as non-coal mines and tunnels.

Research and application of dust control technology based on long pressure and short pumping system in mechanized tunneling face of coal roadway

In order to solve the problem of dust pollution in mechanized tunneling face, Master the best matching relationship between the long and forced ventilation and the dusting and short dust removal parameters in the working face, reducing the dust concentration of working flour to the maximum degree. This paper takes the high-yield dust comprehensive mining face of Wangjialing coal mine as the research background, by establishing CFD model, the effect of dust control on different axial and radial air out ratio of working face is compared, and the parameters range of effective dust control is obtained, and the actual application of the field is verified and analyzed in order to get the best matching parameters of the control dust removal process. The results show that, after increasing the dust control of the wall winder, a fresh air flow transparent wall along the wall of the tunnel is formed in the tail of the roadheader, the dust can be controlled in the area of the front of the work. When the ratio of the axial and radial air out is 1:3, the dust is controlled in the smaller area near working face, the dust control effect is the best. The total and respirable dust concentration of the driver’s position and the 5m position at the tail of the driving machine can be reduced to less than 26.1 mg/m3 and 12.7 mg/m3. The dust control efficiency is above 80%, the overall dust efficiency is up to 94%, the dust reduction effect is obvious, and reduces the occupational hazards of workers.

Reducing agate dust exposure in Khambhat, India: Protective practices, barriers, and opportunities.

AimsAgate workers in Khambhat, India and their community members are exposed to high levels of silica dust and related diseases. Use of effective prevention practices remains low, prompting the need for effective interventions which increase the uptake of and investment in prevention practices. We sought: (a) to describe knowledge, self‐efficacy, and practices among a population of workers, their family members, and neighbors involved in or located close to agate processing; and (b) to explore which factors are related to use of prevention practices and willingness to invest in new dust control technologies.MethodsA community survey was conducted to measure demographics, occupation and financial factors, knowledge, prevention practices, barriers, risk perceptions, and efficacy beliefs. Descriptive statistics were used and, among agate workers, hierarchical logistic regression explored predictors of prevention practice use and willingness to invest.ResultsAmong 1120 respondents, approximately 44%, 35%, and 8% of workers, family members, and neighbors used prevention practices, respectively. Knowledge and risk perceptions were generally high, where efficacy beliefs were low. Workers who had high levels of education, worked at home, and had high efficacy beliefs were more likely to report using prevention practices and being willing to invest. Barriers to prevention practice use included financial barriers, and beliefs that prevention is ineffective and health is not at risk.ConclusionsInterventions and future research should be designed to engage the community to improve preventive behavior, and implement affordable and effective dust control interventions in the agate industry.

Comparing the Implementation of Two Dust Control Technologies from a Sociotechnical Systems Perspective

A sociotechnical system (STS) creates a framework that allows an examination of how social and technical factors affect organizational outcomes within a specific environmental context. STS has been rigorously studied with a primary research focus addressing worker-technology interactions. Although these interactions are important, the social processes and interactions that occur whenever any technical or environmental change is introduced into the system have been undervalued. If social processes are better understood, mining organizations could efficiently prepare and stabilize for such changes. With this goal in mind, we sought to extend STS theory through applying principles of meta-design to analyze the results of two case study interventions. Specifically, we studied the impact of an unregulated dust control technology (the Helmet-CAM) and a regulated dust control technology (the Continuous Personal Dust Monitor) on factors within an STS including employees’ knowledge of, communication about, and use of technology to mitigate respirable dust sources. The results are presented in a way that first, addresses the overarching principles of meta-design STS including organizational participation, flexibility, and communication and second, examines how technology implementation processes differ when the organization is complying with a formal, higher-level requirement. Results show that a prominent focus on the social factors within an STS framework could help reduce unpredictability on the technical side and may improve communication within the system to help reduce adoption time, especially if and when accompanying a new, formal work process.

Coal seam water infusion for dust control: a technical review.

Coal mine dust continues to be a health and safety issue in underground coal mines. Coal seam water infusion was developed and widely applied in European coal mines for dust control, and was also a common practice in most Chinese coal mines. This method typically involves the infusion of water into the coal seam to increase its moisture content, and therefore reduce dust generation during mining operations. With the availability of other dust control methods such as water spraying systems, the water infusion method has not been considered as a viable means for dust mitigation in modern mines. However, the increase in production output and the deployment of more powerful equipment for coal cutting and transport and intensive gas drainage practices mean that workers could be exposed to more dust contaminations. Whilst the mine operators are committed to suppress and dilute airborne dust particles using these passive measures, there is a need to critically examine and subsequently develop this proactive dust control technology for practical applications in Chinese coal mines. The paper provides a critical review of the water infusion technologies in view of its technological advances and practical application limitations. The methods of water infusion, mechanism of water flow in coal, the role of surfactants and the key parameters influencing the effect of water infusion on dust control are identified and discussed. Existing problems and prospects for water infusion are analysed.

Analysis of Dust to Evaluate the Incidence of Pneumoconiosis in Huainan Coal Mines

ABSTRACTEnvironmental pollution is an increasing problem in the world. The goal of the present study was to carry out environmental assessment on pneumoconiosis through comprehensive analysis of the coal mine environment. The dust in the Xinzhuangzi and Xiejiaji coal mines in Huainan was sampled to characterize the permissible concentration–short-term exposure limit and permissible concentration–time-weighted average. The free SiO2 concentration was determined by a pyrophosphate quality method. The concentrations of metals and metalloids were determined by atomic absorption spectrometry. An air microorganism sampler was used to detect bacteria and fungi. The results of permissible concentration–short-term exposure limit of dust samples in the coal mines were 42.59 and 50.00% in excess of the national standard, and the results of permissible concentration–time-weighted average were 27.78 and 25.93% in excess. The concentration of free SiO2 was 11.28 mg/m3; the rock roadway excavation site was obviously higher than at other locations (P < 0.05). The concentrations of Fe, Cu, Zn, Mn, Pb, Ni, Cd, and As were 25.68 ± 7.24 µg/g, 37.21 ± 8.16 µg/g, 64.85 ± 36.97 µg/g, 611.80 ± 70.34 µg/g, 30.15 ± 10.95 µg/g, 106.84 ± 38.68 µg/g, 2.31 ± 1.65 µg/g, and 3.18 ± 1.70 µg/g in dust. The concentrations varied within and between the mines. The concentrations of bacteria and fungi in the air accounted for 73.81 and 26.19% of the total microbial concentration. The bacterial concentration was significantly higher than the fungi concentration (P < 0.001). The particle concentration distribution of air microorganisms peaked in the third (3.3–4.7 µm) and fifth levels (1.1–2.1 µm). The peak values were 1 025 cfu/m3 and 1 134 cfu/m3. In summary, pneumoconiosis was closely related to environmental factors in the Huainan mines. Dust, SiO2 concentration, the presence of microbial granules less than or equal to 5 µm, and heavy metals affected the pulmonary toxicity. This study provided experimental basis for the occurrence of pneumoconiosis and may improve dust control technology, strengthen individual protective measures, and implement standard occupational disease prevention.

A comparative study of dust control practices in Chinese and Australian longwall coal mines

Mine dust is one of the main hazards in underground longwall mines worldwide. In order to solve the mine dust problem, a significant number of studies have been carried out regarding longwall mine dust control, both in China and Australia. This paper presents a comparative study of dust control practices in Chinese and Australian longwall mines, with particular references to statutory limits, dust monitoring methods and dust management practices, followed by a brief discussion on the research status of longwall mine dust control in both countries. The study shows that water infusion, face ventilation controls, water sprays, and deep and wet cutting in longwall shearer operations are commonly practiced in almost all underground longwall mines and that both Chinese and Australian longwall mine dust control practices have their own advantages and disadvantages. It is concluded that there is a need for further development and innovative design of more effective dust mitigation products or systems despite the development of various dust control technologies. Based on the examinations and discussions, the authors have made some recommendations for further research and development in dust control in longwall mines. It is hoped that this comparative study will provide beneficial guidance for scholars and engineers who are engaging in longwall mine dust control research and practice.

Study on Control Technology of Industrial Sticky Dust

Based on the physical property analysis of sticky dust, the paper explained the effect of temperature, relative humidity, pressure, etc. on adhesion of dust. And focusing on these factors, take the silicon steel sticky dust for example, proposed two kinds of dust control technology: pipeline heat tracing technology and gas conditioning of SO3, both help improve system efficiency by selecting the appropriate dust collector.

Tunnel Construction Dust Monitoring and Dust Control Technology of High Altitude and High and Cold Area

In order to improve the high altitude harsh construction environment, study tunnel construction dust concentration and distribution law of different construction section, using the membrane filter dust method to achieve the dust concentration of different section, using the statistical to analysis the origin and distribution law, putting forward different dust control measures for different construction stages, to improve the high altitude tunnel construction environment. The results of dust prevention and control of high altitude region are of great significance.

The Practice and Innovation of Coal Dust Control Technology in Comprehensive Tunneling Face

According to the characteristics of the tunneling working face dust, the digging machine spray and airflow purifying water curtain linkage automatic spraying dust settling technology, improved the precipitator, research and application of high pressure spray technology, make the tunneling working surface has good dust fall effect, to ensure the workers health and safety in production of coal mine.

미세먼지 관리기준과 발생원별 관리방안

This paper has comprehensively reviewed fine dust control technology from emission sources. Owing to the stringent national regulation, domestic industries have made consistent efforts to develop the high efficiency facilities since 1960s. In these days, harmful particulate pollutants including dioxins and PAHs as well as are also of critical interests in government and civic groups. In addition, simultaneous treatment of gas and particles is being widely studied. It is believed that hybrid facilities which integrate a few advanced equipment may meet the atmospheric guidelines.

Wind-Induced Vibration Analysis of Wind Fence Structure

As a new wind-break and dust-control technology, the wind fence is widely used at storage yards in factories and ports. The wind fence structure is a new high-rise wind-resistant structure with light damp and very heavy wind load, and the wind-induced vibration response is unknown and equivalent static wind load is hard to determine in design. Based on the Davenport spectrum, wind-induced vibration of the plane frame structure was analyzed with frequency domain method and the response spectrum of displacement and acceleration were obtained. The equivalent static wind load was studied and the wind-induced vibration coefficient and gust loading factor were gained. The results show that the wind-induced vibration response of the structure is significant, and it should be taken into consideration in structural design.