At present, the buried integrated sewage treatment equipment is generally divided into two types, one can be made into a round tank and the other is square. Nowadays, circular cans are rarely seen in the market, and they are generally made into squares unless customers specifically request them. Because the circle is more troublesome to make and needs to be rolled, the internal welding is not as convenient as that of the square, and the cost is relatively lower than that of the square. Generally speaking, buried sewage treatment equipment consists of three parts. Square ones can be divided into squares, which is relatively convenient to make, while circular ones need to be made into concentric circles, which is more troublesome to make and requires more materials. In addition to making trouble, the installation and transportation of the circle is not as convenient as that of the square. These two shapes look different, but the treatment effect is the same, so now most manufacturers are transforming into cubes, which are easy to recognize.