METHOD FOR CONSTRUCTION OF UNDERGROUND VESSEL IN DEPOSITS OF ROCK SALT Russian patent published in 1998 - IPC

FIELD: construction engineering. SUBSTANCE: this relates to creation of underground vessels in rock salt deposits for use as storage of petroleum products. Method implies creation of vessel by process of lixiviation (dissolving) with water injected through bore-hole. Used as nonsolvent agent is diesel fuel or kerosene. Purpose of invention is diminishing of error in determining amount of non-recoverable residue of nonsolvent agent from vessel so as to make more reliable forecasting in change of quality of light petroleum products injected into underground reservoir. According to method, installed concentrically into bore-hole are casing string, external and internal working pipe strings. Water for dissolving is delivered into annular space between internal and external concentric working pipe strings. Accompanying construction brine is withdrawn to ground surface through internal working pipe string. Liquid nonsolvent agent is injected into annular space between casing string and external working pipe string with simultaneous recording of water flow rate used for washing-out, and flow rate of construction brine outflowing from vessel. Recorded are temperature of outflowing brine and concentration of salt in it. According to these data, calculated are mass of washed-out rock salt and volume of vessel thus created. Additionally in process of dissolving salt after determined time intervals measured is current value of concentration of nonsolvent agent in construction brine. Also determined is total amount of nonsolvent agent removed by construction brine. This amount is taken into consideration in determining non-recoverable residue of nonsolvent agent in underground vessel. EFFECT: higher efficiency. 1 dwg, 1 tbl