1991 Volume 20 Issue 7 Pages 437-444
Recently, the utilization of reclaimed land by municipal wastes to the residential quarter is becoming the object of attention in many local governments, as the wastes under the ground would be completely decomposed within 10 or 20 years. However, many troubles have occurred by the generation of dangerous and offensive gases discharging from the waste layer when the ground was dug up.
In this study, an investigation on the removal method of gases being in the waste layer under the ground was carried out and a suction model of gas from the central boring pipe was proposed. As a result, it was decleared that the distribution of gas flow rate in the waste layer and covered surface soil were obtained based on the ratio of gas permeability coefficient between waste layer and surface soil.
And this model is applied to estimate the change of gas concentration in the waste layer, and it was confirmed that higher efficiency of gas suction will be obtained with the increasing of thickness or reducing the gas permeability coefficient of covered surface soil.
And also, the suction rate of gases is proportional to the capacity of vacuum pump, and a higher efficiency of gas suction is obtained to increase the distance of ditch from central pipe, but this method increase the required time for the suction because the total volume of gases to be suck up become to four hold, when the radius makes double.
