(a)先開放該污水過濾槽10的淨水排水管15的第二閥門17，關閉該過濾

(a)先開放該污水過濾槽10的淨水排水管15的第二閥門17，關閉該過濾砂清洗槽30的進砂管31的第三閥門33與出砂管32的第四閥門34，並關閉該逆洗噴管40的第五閥門41，以及關閉該污泥排放裝置50；

結果 (英文) 2:

(a) First open the sewage filter tank 10 of the second valve 15 of the water purification drainage pipe 15, close the filter sand cleaning tank 30 of the third valve 33 of the sand pipe 31 and the fourth valve 34 of the sand pipe 32, and close the fifth valve 41 of the reverse wash nozzle 40, and close the sludge drainage device 50;

結果 (英文) 3:

(a) first open the second valve 17 of the clean water drain pipe 15 of the sewage filter tank 10, close the third valve 33 of the sand inlet pipe 31 of the filter sand cleaning tank 30 and the fourth valve 34 of the sand outlet pipe 32, close the fifth valve 41 of the backwash nozzle 40, and close the sludge discharge device 50;