| 摘要 |
<p>The invention concerns a method for mining sand or gravel from a sand or gravel deposit at the bottom of a body of water, comprising the following steps: i) providing mining machinery capable of conveying sand or gravel from a mining position at the bottom of said water to a desired location, said mining position being at a level relatively lower than the upper limit of said deposit of sand or gravel to be mined; ii) providing water injection means capable of injecting water into the sand or gravel deposit iii) injecting water into said deposit by said injection means, in an amount and at a rate selected so that the sand or gravel and the injected water form a liquefied layer, said liquefied layer being capable of flowing under the influence of gravity from the place of said deposit to the lower level mining position, and iiii) mining said sand or gravel by means of said mining machinery, after said sand or gravel has flown from said deposit to said mining position.</p> |
