| 摘要 |
The present invention relates to improved chemical additives for use in hydraulic fracturing fluids for the recovery of oil or natural gas entrained in deep-layer shale formations. Many chemical agents currently in use in such water/sand (or other proppants) mixtures could pose human and animal health risks if these chemicals migrate from the shale beds into the environment contaminating the water table, rivers, streams and lakes. The fracturing fluid chemical additives of this invention are designed to be retained or anchored in or near the deep shale layers and are prevented, or greatly delayed from upward migration. Specifically, many chemical additives required for proper fracturing fluid performance can be chemically bonded to inert particulate materials before incorporation into said fluids. The fracturing fluid chemical additives are able to perform their function in the shale fracturing process, and then become nearly permanently trapped in the shale layers protecting the environment above. |
