By adding composite powder carriers to the biological pool, not only was the concentration of the mixed liquor in the biological pool increased, but a microbial system with both suspended growth and attached growth 'dual mud' symbiosis was constructed; through the sludge thickening separation unit and the composite powder carrier recovery unit, dual mud age was achieved, and the efficiency of biological denitrification and phosphorus removal was enhanced. The sludge concentration in the HPB technology biological pool is 6-10g/L, MLVSS/MLSS is 0.30-0.38, the BOD5 sludge load is 0.04-0.2kgBOD5/(kgMLSS·d), the sludge age is 15-21d, the sludge return ratio is 50%-100%, the mixed liquor return ratio is 100%-400%, and the hydraulic retention time is 5-8 hours. The effect of enhanced biological denitrification and phosphorus removal is achieved, with the effluent stably meeting the quasi-IV standard. Compared with traditional activated sludge process, it reduces carbon source consumption by more than 35%. The removal of carbon dioxide emissions per ton of COD can reduce by 3.2 tons, significantly improving the level of carbon reduction. Compared with wastewater treatment projects that meet emission standards, it saves 30% in land occupation, 20% in investment and operating costs, and reduces the construction period by more than 30%.