| 摘要 |
<p>In a method of the type where petrol is recovered from a mixture of petrol vapour and air by absorption of the petrol in a cooled petroleum distillate, a petroleum distillate having a boiling point range higher than that of the petrol is used, and this petroleum distillate is in sequence cooled by heat exchange with a could reservoir, brought into direct contact with the petrol/air mixture to absorb petrol, transferred to a buffer tank and transferred from the buffer tank to a stripping means which may be a distillation column. By combining cooling condensation and absorption of the petrol vapour and controlling the amount of cooled petroleum distillate brought into contact with the petrol/air mixture so that the petrol concentration in the petroleum distillate transferred to the buffer tank is substantially constant, an unprecedented optimum control of the petrol absorbing process can be obtained both in peak load and in average load operations. A system for carrying out the method is advantageous in that only the absorption means (2) need be dimensioned for peak load operation, while the other components, such as the distillation column (5) or a heat exchanger (4) with associated conduits can be dimensioned for average loads, a buffer tank (3) being provided to temporarily receive the petroleum distillate which owing to the above-mentioned control (15, 16) has a substantially constant, maximum petrol concentration so that the system can cope with peak loads with a surprisingly small buffer tank (3).</p> |
