A practice of ultra-fine tailings disposal as filling material in a gold mine.

Transportability and pressure drop of fresh cemented coal gangue-fly ash backfill (CGFB) slurry in pipe loop

Pressure drop in loop pipe flow of fresh cemented coal gangue–fly ash slurry: Experiment and simulation

A hydraulic gradient model, which can be used to compute the hydraulic gradient of paste-like crude tailings backfill slurry (PTBS) transported by a pipeline system in a mine, was constructed based on rheological model derivation, numerical simulation, and regression analysis. It was proven, by a Bingham rheological model analysis of the PTBS, that the hydraulic gradient of the PTBS is inversely proportional to the pipe diameter and proportional to the average flow velocity. It was also clarified that the hydraulic gradient value depends primarily on the rheological parameters of the PTBS if the pipe diameter and flow velocity are adjustable. Consequently, rheological parameters of the PTBS in different slurry mass fractions were obtained through 3D simulation with FLUENT. The slurry pipeline transportation process and the relationship between rheological parameters and slurry mass fraction were regressed by MATLAB mathematical software. Finally, a hydraulic gradient model describing a variation rule of the hydraulic gradient of the PTBS to pipe diameter, flow velocity, and slurry mass fraction was constructed. A comparable study between the calculation result and site date indicates that the model has enough accuracy to satisfy the requirement of backfill system design with an average deviation of 8 %.

A hydraulic gradient model of paste-like crude tailings backfill slurry transported by a pipeline system

Design considerations for hydraulic backfilling with coal combustion products (CCPs) at high solids concentrations

Taking cemented coal gangue pipeline transportation system in Suncun Coal Mine, Xinwen Mining Group, Shandong Province, China, as an example, the hydraulic calculation approaches and process about gravity pipeline transportation of backfill slurry were investigated. The results show that the backfill capability of the backfill system should be higher than 74.4 m3/h according to the mining production and backfill times in the mine; the minimum velocity (critical velocity) and practical working velocity of the backfill slurry are 1.44 and 3.82 m/s, respectively. Various formulae give the maximum ratio of total length to vertical height of pipeline (L/H ratio) of the backfill system of 5.4, and then the reliability and capability of the system can be evaluated.

http://www.zndxzk.com.cn/down/paperDown.aspx?id=59144

Hydraulic Calculation of Gravity Transportation Pipeline System for Backfill Slurry

Under China’s modern development concept, it is necessary to promote the application of electric equipment to improve the construction environment of high-altitude railway tunnels and to address the efficiency reduction in high-altitude construction of traditional fuel oil equipment. Based on the analysis of the development status of electric equipment for tunneling projects in China, a tripartite evolutionary game approach is used to establish the game payment matrix of the government, equipment manufacturers, and construction units. The impact of the relevant parameters on the tripartite strategy is investigated based on numerical simulations. It has been shown that in the early stages of popularization and application, the government should actively regulate and control, and in the later stages of popularization and application, the government should play a leading role in market mechanisms. Evolutionary stability strategies are affected by the brand revenue that manufacturers earn through technological innovation on electric equipment and the additional research and development costs that need to be paid. The conclusions of this study can help provide a reference for the promotion and application strategy of electric equipment in China’s plateau railway tunnels.

/pdf/research-on-promotion-and-application-strategy-of-electric-27mxvnoz.pdf

Research on Promotion and Application Strategy of Electric Equipment in Plateau Railway Tunnel Based on Evolutionary Game

China has always been an agricultural country. The hilly area covers a large area and the road condition is poor. At present, it is difficult for agricultural transporters on the market to operate efficiently in this area, so it is necessary to improve their adaptability to the hilly landform. Crawler transporter is a main type of machine widely used in agricultural transportation. Compared with wheeled transporter, crawler transporter has good adhesion performance and is not easy to slip. When driving on soft clay road, its ground pressure and road subsidence are smaller, so crawler transporter is more widely used.

/pdf/simulation-analysis-of-track-transporter-based-on-recurdyn-1ss2xrrk.pdf

Guan-yu Hu

Papers

Hydraulic Calculation of Gravity Transportation Pipeline System for Backfill Slurry

Research on Promotion and Application Strategy of Electric Equipment in Plateau Railway Tunnel Based on Evolutionary Game

Simulation Analysis of Track Transporter based on Recurdyn