Horizontal wells sandstone acidizing

Sandstone acidizing in horizontal wells is difficult because of placement limitations. Horizontal zones are typically longer than zones in vertical wells. Horizontal intervals can be many thousands of feet. Mechanical isolation with packers, which is the most effective method of placing acid in vertical wells, is not often practical in horizontal zones. Too many packer settings are required, extending beyond the limits to which current commercial packer systems can be effectively seated and reseated. 

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