基于响应面法的碎软煤层钻进泡沫冲洗液配方优化研究

Optimization of foam drilling fluid for broken and soft coal seam drilling based on response surface methodology

摘要:

针对碎软煤层空气螺杆钻进过程中粉尘危害突出、煤粉携带困难、现有泡沫冲洗液体系抗污染与抗压性能不足等技术难题，构建适配该工况的泡沫冲洗液体系。通过性能筛选确定发泡剂DF-1、稳泡剂MZ-1、抗污染剂MPS和抗压剂HS植物胶为核心组分，采用单因素实验得到各组分的基础较优浓度分别为0.9%、0.3%、0.4%、0.3%，进而基于响应面法构建四因素三水平Box-Behnken实验模型，探究各组分交互作用对发泡体积与半衰期的影响规律，结合现场钻探循环时间需求进行配方优化。结果表明：各因素对发泡体积影响的显著性排序为MZ-1>HS植物胶>MPS>DF-1，对半衰期影响的显著性排序为MZ-1>MPS>HS植物胶>DF-1；结合现场钻探泡沫循环需求，得到目标半衰期为40 min的最优配方为1.1% DF-1+0.1% MZ-1+0.5% MPS+0.3% HS植物胶；验证实验显示该配方发泡体积510 mL、半衰期46 min，抗污染性与抗压性均显著提升，FCI下降率28.91%、压缩率73.33%，可有效满足碎软煤层安全高效钻进需求。研究证实响应面法可对多组分泡沫体系进行协同优化，所建配方兼具优良发泡与稳泡性能、抗污染及抗压性能，为碎软煤层安全高效钻进提供技术支撑。

Abstract:

To address the technical challenges of severe dust hazards， difficulties in coal fines transport， and insufficient anti-contamination and compressive resistance of existing foam drilling fluid systems during air screw drilling in broken-soft coal seams， a foam drilling fluid system suitable for this working condition was developed. Through performance screening， the foaming agent DF-1， foam stabilizer MZ-1， anti-contamination agent MPS， and compression-resistant agent HS plant gum were identified as the core components. Single-factor experiments yielded the preliminary optimal concentrations of these components as 0.9%， 0.3%， 0.4%， and 0.3%， respectively. Subsequently， a four-factor， three-level Box-Behnken experimental model was constructed based on response surface methodology （RSM） to investigate the interactive effects of the components on foam volume and half-life， and formulation optimization was performed considering the circulation time requirements of field drilling. The results indicate that the significance order of factors affecting foam volume is MZ-1>HS plant gum>MPS>DF-1， and that affecting half-life is MZ-1>MPS>HS plant gum>DF-1. Considering the foam circulation requirements of field drilling， the optimal formulation achieving a target half-life of 40 min is determined as 1.1% DF-1+0.1% MZ-1+0.5% MPS+0.3% HS plant gum. Validation experiments demonstrate that this formulation produces a foam volume of 510 mL and a half-life of 46 min， with significantly improved anti-contamination and compressive resistance， FCI reduction rate of 28.91% and compression ratio of 73.33%， effectively meeting the requirements for safe and efficient drilling in broken-soft coal seams. This study confirms that RSM can synergistically optimize multi-component foam systems， and the developed formulation exhibits excellent foaming， foam stability， anti-contamination， and compressive resistance properties， providing technical support for safe and efficient drilling in broken-soft coal seams.