Abstract: Based on the mature laboratory test results, a 1 kt/a high gravity pilot plant unit was set up to produce overbased calcium petroleum sulfonate detergent for lube oil, optimum process conditions and the post treatments of “three wastes” from production were investigated. Results of pilot plant tests showed that the optimal reaction time of carbonation was in the range of 58—62 min, during this time, the base number and the kinetic viscosity of the product was 315.2 mgKOH/g and 35.6 mm2/s, respectively. Using horizontal screw centrifuge to pre-treat the crude product was better than that of the conventional gravitational settling method with tank. The quality of the overbased calcium petroleum sulfonate detergent prepared by high gravity pilot plant could well meet the 1st class product requirements of SH/T0042—91 trade standard, and its detergent performance was better than that of the conventional tank produced one. In addition, the adopting post treatments could ensure low discharge of pollutants during production.