| 摘要 |
<p>PURPOSE:To treat combined drainage of high BOD by carrying out the solid- liquid separation of liquid to be treated in a biological treatment tank in which active sludge is floated, feeding concentrated liquid into a sludge digestion tank and permeated liquid into a disinfection tank respectively and disposing properly. CONSTITUTION:When liquid to be treated which is the combined drainage of bath drainage, washing drainage, excrement, kitchen drainage and the like is treated, first the liquid to be treated is fed into biological tanks S1 and S2 through an introduction pipe 5 in which intermittent aeration is carried out and anaerobic treatment and aerobic treatment are repeated. Then the liquid to be treated coming out of the biological treatment tank S1 is fed to a film separation device 10 and solid-liquid separation is carried out, and the permeated liquid is fed to a disinfection tank S5 through a storage tank S6, disinfected and discharged. On the other hand, concentrated liquid containing active sludge is fed into a sludge digestion tank and organic matters such as sluge are turned into methane or carbon dioxide gas by means of anaerobic digestion and discharged or exhausted outside the system. The digested liquid (supernatant) in the digestion tank is returned to the biological tank S1.</p> |
