What should be the length of indoor horizontal drainage pipe 19 meter slope? Upstairs is a hotel, in the form of a big bag table, with a large amount of sewage, just under the shed on the first floor

What should be the length of indoor horizontal drainage pipe 19 meter slope? Upstairs is a hotel, in the form of a big bag table, with a large amount of sewage, just under the shed on the first floor of my house. Generally, the gradient of horizontal pipes of indoor drainage pipes is not less than 0.0026, but it will be 0.005 ~ 0.0 1 in design and construction, and 0.02 if there is enough space. It is recommended to keep the slope at least 0.0 15. The drainage pipe of the hotel has a large displacement, so the slope of the drainage pipe should be as large as possible.