本文選題：表面活性劑 + 表面張力�。� 參考：《湖南科技大學》2017年碩士論文

【摘要】：煤塵爆炸造成大量的人員傷亡和巨大的經(jīng)濟損失,煤塵的安全隱患和職業(yè)健康問題日益嚴峻。目前,噴霧降塵是煤礦井下最常用的防塵技術措施,然而其噴霧降塵效果較差,尤其是對呼吸性粉塵,因此針對噴霧降塵技術、煤塵的潤濕性開展進一步研究,對控制井下作業(yè)環(huán)境的粉塵濃度,確保煤礦安全生產(chǎn)具有十分重要的意義。論文主要針對以下三個方面進行了實驗研究;(1)論文從表面張力、接觸角和沉降實驗三個方面對表面活性劑與煤塵的濕潤性進行實驗研究。在表面活性劑溶液中加入高價陰離子電解質(Na2SO4等),通過對其溶液的表面張力測定,發(fā)現(xiàn)在表面活性劑溶液中加入高價陰離子電解質能夠提高表面活性劑溶液的潤濕能力;就不同粒徑的煤粉壓片進行接觸角的實驗測定,發(fā)現(xiàn)不同粒徑的煤粉壓片的接觸角差異很大,其粒徑越小,接觸角越大,潤濕性越差;同時通過對接觸角的測量研究了不同煤質對其濕潤性的影響,發(fā)現(xiàn)灰分含量越高,其濕潤性越強。通過接觸角測量和沉降實驗分析發(fā)現(xiàn),所選四種表面活性劑對潤濕煤塵的效果有差異,其中非離子表面活性劑OP-10在質量濃度為0.005%左右時效果最好。(2)為了分析煤礦井下氣水噴霧霧化特性,基于自行設計的氣水噴霧試驗平臺,采用電磁流量計、空氣質量流量計及馬爾文實時高速噴霧粒度分析儀對空氣霧化噴嘴流量特性、霧化粒度的空間分布規(guī)律及影響因素開展了實驗研究。并就氣水混合噴嘴與壓力式螺旋噴嘴進行對比,發(fā)現(xiàn)氣水混合噴嘴具有很明顯的優(yōu)勢,在較低的供水壓強和供氣壓強條件下的霧滴粒徑D[3,2]就能達到螺旋式噴嘴在超高壓強下的霧滴粒徑D[3,2],而且耗水量遠比螺旋式噴嘴的小,可以很大程度上節(jié)約成本,減少資源的浪費。最后就添加表面活性劑對霧化效果的影響進行實驗研究,發(fā)現(xiàn)在噴霧介質中添加表面活性劑,其噴霧霧滴粒徑隨濃度增加而緩慢減小,當濃度達到其臨界約束濃度后,噴霧的霧滴粒徑D[3,2]會隨濃度增加而增大。(3)基于可仿真煤礦井下采掘工作面通風、產(chǎn)塵及噴霧等狀態(tài)的氣水噴霧實驗系統(tǒng)上,運用實驗的方法,針對影響噴嘴噴霧降塵效率的因素開展了研究。通過對比氣水混合噴嘴和螺旋式噴嘴在不添加表面活性劑和添加表面活性劑兩種情況下的全塵和呼吸性粉塵的降塵效率,發(fā)現(xiàn)這兩種噴嘴在其霧化特性最好的工況下,其降塵效果也較好,而且氣水混合噴嘴的呼吸性粉塵降塵效果比螺旋式噴嘴要好。在添加表面活性劑后,氣水混合噴嘴的全塵和呼吸性粉塵的降塵效率都比未添加時的高,降塵效率隨表面活性劑濃度的增加而逐漸升高,當濃度達到其臨界約束濃度后,降塵效率升高的幅度變緩。綜合實驗結果,在氣水混合噴霧中添加表面活性劑可以增強霧滴表面活性,改善霧化效果,提高降塵效率,為以后噴霧降塵深入研究提供參考。
[Abstract]:Coal dust explosion has caused a large number of casualties and huge economic losses, and the safety risks and occupational health problems of coal dust are becoming increasingly serious. At present, spray dust control is the most commonly used dust control technology in coal mines. However, the effect of spray dust reduction is poor, especially for breathing dust. Therefore, the wettability of coal dust is further studied in the light of spray dust control technology. It is of great significance to control the dust concentration in underground working environment and to ensure the safety of coal mine production. In this paper, the wettability of surfactant and coal dust was studied from three aspects: surface tension, contact angle and sedimentation. The surface tension of surfactant solution was determined by adding high valence anionic electrolyte (Na _ 2SO _ 4) to surfactant solution. It was found that the wetting ability of surfactant solution could be improved by adding high-valence anionic electrolyte to surfactant solution. The contact angle of pulverized coal pressed pieces with different particle sizes is measured by experiments. It is found that the contact angle of different particle sizes is very different, the smaller the particle size is, the greater the contact angle is and the worse the wettability is. At the same time, the influence of different coal quality on its wettability is studied by measuring the contact angle. It is found that the higher the ash content is, the stronger the wettability is. Through contact angle measurement and settlement analysis, it is found that the four surfactants have different effects on wetting coal dust. The Nonionic surfactant OP-10 has the best effect when the mass concentration is about 0.005%. In order to analyze the atomization characteristics of gas-water spray in coal mine, an electromagnetic Flowmeter is used based on the air-water spray test platform designed by ourselves. The air quality Flowmeter and Ma Erwen real time high speed spray particle size analyzer were used to study the flow characteristics of air atomizing nozzle, the spatial distribution of atomizing particle size and the influencing factors. By comparing the air-water mixing nozzle with the pressure spiral nozzle, it is found that the air-water mixing nozzle has obvious advantages. Under the condition of low water supply pressure and air supply pressure, the droplet diameter D [3N 2] can reach the diameter D of the spiral nozzle under the super high pressure, and the water consumption is much smaller than that of the spiral nozzle, which can save the cost to a great extent. Reduce the waste of resources. Finally, the effect of adding surfactant on the atomization effect was studied. It was found that the particle size of spray droplet decreased slowly with the increase of concentration, and when the concentration reached its critical confinement concentration, the spray droplet size decreased slowly with the increase of the concentration of surfactant in the spray medium. Spray droplet diameter D [3N 2] will increase with the increase of concentration.) based on the air-water spray experimental system which can simulate the ventilation, dust production and spray of underground mining face, the experimental method is used. The factors influencing the efficiency of spray dust removal were studied. By comparing the dedusting efficiency of total dust and breathing dust between air-water mixed nozzle and spiral nozzle without surfactant and surface active agent, it is found that the two nozzles have the best atomization characteristics under the working conditions. The dust control effect of the air-water mixing nozzle is better than that of the spiral nozzle. After the addition of surfactant, the dust removal efficiency of the air-water mixing nozzle was higher than that of the non-added nozzle. The dust removal efficiency increased gradually with the increase of surfactant concentration, and when the concentration reached its critical confinement concentration, the dust removal efficiency increased gradually with the increase of surfactant concentration. The extent of the increase in dust reduction efficiency has slowed down. The experimental results show that the surface activity of droplets can be enhanced, the atomization effect can be improved and the dedusting efficiency can be improved by adding surfactants to the air-water mixed spray, which provides a reference for the further study of spray dust control.
【學位授予單位】：湖南科技大學
【學位級別】：碩士
【學位授予年份】：2017
【分類號】：TD714.4

【參考文獻】

相關期刊論文 前10條

1 王鵬飛;劉榮華;桂哲;茍尚旭;舒威;譚p蓽，

本文編號：2007840