This article introducesa new type of detergent TS-198, which is specially suitable for processing sand filter material containing graphite and greasy dirt in filter tank.It can not only clean greasy dirt but also stripe the graphite adhering to the grains of the sand filter material.The experiment shows that TS-198 has superior cleaning effect on graphite and greasy dirt adhering to the sand filter material.Its comprehensive qualities surpass that of detergent D-26 of DREW Company.