Biological mini sewage treatment plant for yachts, houseboats and holiday apartments

摘要

Use of a tube with a suitable surface coating for adhesion of bacterial film and simultaneous enlargement of the bacterial film surface by use of a corrugated tube and thus significant enlargement of the film and thus the effective surface available for processing, which correlates with the amount of bacteria: The coating is carried out by a mechanical chemical process: First, the entire corrugated tube (PVC material with PVC spiral) is roughened by sandblasting inside and outside. Here, no material removal may take place, but only a roughening of the surface. Therefore, crushed nutshells are used as blasting agents. The grain sizes are all variants smaller than 500 microns are used. The corrugated tube is thus blown inside and irradiated on the outside until a velvety surface structure is obtained. This is already the case after a few seconds of processing. Thereafter, in the entire tube, which is up to 10 m long per section in the reactor, radially small holes for the passage of water are perforated (3). For this purpose, a punching tool with 0.5 mm diameter is used. On the entire circumference every 1 cm and over the entire length every 1 cm a hole is punched, which has a diameter of 0.5 mm. With a hose diameter of 40 mm, this results in 12 holes per circumference, as well as 1 meter hose length 100 rows with a total of 1,200 holes per meter. With 10 m inserted hose in the tank, this results in 12,000 perforations each with a diameter of 0.5 mm. The cross-sectional area per perforation is according to the formula ca. 0.1963 mm2 and is further assumed to be 0.2 mm2; The 12,000 drill holes thus produce a total passage area of approx. 2,400 mm2, which corresponds to a passage area of 24 cm2. This total area corresponds to a hole diameter of about 5.5 cm or 2.2 inches. Approximately 18 liters of liquid can pass through per hour if the assumed flow rate is 0.2 cm / sec. The final production of the biofilm is carried out by inserting the entire tube in a tank (1), in which there are sugar cane molasses and a concentrate of the later used activated microorganisms. By increasing the temperature in the tank, a fermentation process is started, which leads to the formation of a film on the hose surface. The raw materials are sugar cane molasses or rice syrup and a bacterial concentrate are used, the whole is mixed in a ratio of 1 l molasses or rice syrup + 1 liter of bacteria-original solution + 33 liters of water, kept with a heater at 34 degrees Celsius and 7 days under exclusion of air (fermentation required for air release) fermented (2). The process is complete when the pH in the liquid reaches between 3.2 and 3.6. The exact mixing ratio of the tank liquid is 3% molasses or rice syrup, 3% urine solution and 94% warm water. To dissolve the molasses, the water may be up to 60 degrees Celsius warm, until it has been added to the original solution, it must be cooled to 36 degrees Celsius. The coated hose must be installed moist in the system immediately after production and must then be put into operation within 2 weeks.