rate contract of boilers chemicals for maintaining p.h. and t.d.s. . , rate contract of boilers chemicals for maintaining p.h. and t.d.s..: , boiler chemicals to maintain the ph-10, tds max. 1500, phosphate 20, boiler water should be free of oxygen. nhc / basf / thermax / ion exchange / chemcon- make ( dose per day ) hydrogen base ( boiler capacity 25 ton per hour ) sludge chemical n-63 / 3223, oxygen savenger n-61 / 3100, p.h. booster n-70 / 3006 for boiler n-70 etc. with technical supervisor. ( as per requirement ) ( during crushing season 2022-23 ) note:- boiler shall have to maintain parameter as following:- ( i ) ph – 9.5 to 10.5, ( ii ) t.d.s.- 1000 to 1500 rpm ( iii ) po4 – 10 to 20 ppm ( iv ) so3 – 20 to 30 ppm ( v ) n2h4 – 0.1 to 0.4 ppm ( vi ) t-alka – 300 to 400 ppm ( vii ) oh-alka- 150 to 200 ppm, ( viii ) rine ph – to 15