The invention discloses a multi-span
greenhouse rainwater collecting and treating reusing device which comprises a water gathering
pipe, initial rainwater filtering devices, a double power supply
programming controller, a safety diverting well, a modular
water storage pond, a pressurizing pump, a multi-medium filter, an
ozone generator, a Venturi ejector and a
clean water pond, wherein the initial rainwater filtering devices are used for initially realizing
filtration of rainwater of 2-5mm; the double power supply
programming controller is used for controlling the liquid level of the
water storage pond and switching of the initial rainwater filtering devices; the safety diverting well is used for precisely filtering rainwater and controlling the water quantity; the
ozone generator and the Venturi ejector are used for generating
ozone water. The invention further discloses a rainwater collecting and treating reusing method based on the device. According to the device and method disclosed by the invention, the collected rainwater is disinfected and sterilized by using the ozone water so as to solve the problem that the
water quality in the
water storage pond is deteriorated, so that the rainwater is recycled, and therefore, the utilization efficiency of a water resource is improved, the regional
ecological environment is improved, and an extra economical benefit is further generated.