New MSW installations
The separation of household waste (MSW) with the use of Walair air separation systems gets better known and is used worldwide regularly. With the use of Walair 3-way drum separators the necessary installation behind the air separation system is simpleﬁed and can handle more capacity. But one more interesting advantage with the use of Walair air separation systems is that the total investment of complete installations will be reduced importantly. After the succesfully built 3-way drum separator in Mexico City, the Walair production is producing four 3-way drum separators and two single drum separators for delivery in the coming months. In this item we discuss the air separation system for a customer in the USA.
Operating principle of the 3-way Drum Separators
After screening, the Walair 3-way Drum Separators are separating the MSW input fraction in 3 separate fractions. One heavy fraction, one 3d fraction and a 2d ﬂat part fraction. The heavy fraction which is released by the ﬁrst drum separator consists of material with a m3/ weight of more than 500kg/m3. The rest of the fraction is blown over the ﬁrst drum into the second separation room and transported and blown to the second drum separator. In the second drum separator the 3d fraction is separated from the 2d ﬂat fraction. In the 3d fraction there is still a small amount of 2d ﬂat fraction paper and plastic (>10%). This small amount of paper and plastic is removed by an optical sorter in a later stage. The ﬂat 2d fraction which consists of paper and plastic parts is blown over the second rotating drum and dropped at a 2300 mm width conveyor. At this conveyor the ﬂat paper and plastic is well divided and dosed. This conveyor is placed under the second expansion room. Directly behind this conveyor an optical sorter is placed, which is taken care of the separation of paper and plastic.
These 3-way drum separators handle a total capacity of approx. 30t/h. The cubic weight of the input material is approx. 200kg.
Werkingsprincipe van de luchtscheiding doormiddel van Walair ventilator scheiders
The air separation is taken care by two Walair fan separators. Each suction side of the fan is connected with ducting to the expansion rooms and extracted 100% from the air out of the expansion rooms. Approx. 80% of the air is blown into the blowing mouth of the separation room of the drum separators. The rest of the approx. 20 percent is transported by ducting to automatic cleaned dust ﬁlters. By the use of frequency regulators and air regulation valves, it is possible to adjust the best possible amount of air for each installation.