Co-Treatment of Septage and Fecal Sludge in Sewage Treatment Facilities

摘要

Most developed countries use water-borne sewerage systems to manage urban sewage. Many developing countries take this as a model for the future in their own cities, and these countries too have tended to lean towards networked sewerage to solve urban sewage problems. Sewerage is a good solution which protects public health and the environment by effective containment, transport and treatment of sewage. However, it is a very expensive solution, and difficult to implement effectively. Nevertheless, many cities in the developing world already have sewage treatment facilities, and many more are planning to install such facilities. Over the past few years, on-site treatment has been widely promoted as a process, which can be implemented quickly, to address problems in sanitation and is becoming more widely accepted. As such, treatment of the contents of on-site containments (septic tanks, vaults or pits) has become a pressing issue. While dedicated treatment facilities for this purpose have been advocated, co-treating these wastes in sewage treatment facilities is also a promising option, which many countries have implemented or are cautiously exploring. This option maximises the utilisation of city infrastructure, and is therefore advantageous. In cases where the existing sewage treatment facilities are underutilised, co-treatment presents a ready solution for managing fecal sludge (FS) and septage. In developed countries, co-treatment is practiced widely, but with very small quantities of septage in comparison to the sewage flows. This is because very large portions of the cities are extensively sewered, and on-site systems are few. The situation in developing countries is often reversed, with large parts of the cities using on-site systems.