NPEIC reactor is a new generation of highly efficient anaerobic reactor. Wastewater flows from bottom to top in the reactor, pollutants are absorbed and degraded by bacteria, and purified water flows out from the upper part of the reactor. The basic structure of the NPEIC reactor is similar to that of the two-layer UASB reactor in series. According to the functional division, the reactor is divided into five zones from bottom to top: mixing zone, the first anaerobic zone, the second anaerobic zone, the precipitation zone and the gas-liquid separation zone.
When the NPEIC reactor is treating medium and low concentration wastewater, the inlet volume load rate of the reactor can be increased to 20 ~ 24kgCOD (m³/d). When high concentration organic wastewater is treated, the inlet volume load rate can be increased to 35 ~ 50kgCOD (m³/d). Compared with UASB reactor, in the same conditions of treatment effect, the water volume of the NPEIC reactor has higher rate and sludge load rate, average NPEIC reactor riser speed can be up to 20 times. Dealing with the similar wastewater UASB reactor at low concentration wastewater treatment, HRT can be reduced to 2.0 ~ 2.5 h, the volume of reactor is smaller.
> High volume load: the sludge concentration in the NPEIC reactor is high, the microorganism quantity is large, and there is internal circulation, the mass transfer effect is good, the influent organic load can be more than 3 times of the ordinary anaerobic reactor.
> Saving investment and occupying area: the volume load rate of NPEIC reactor is about 3 times higher than that of ordinary anaerobic reactor, and its volume is about 1/4 ~ 1/3 of that of ordinary reactor.
> Strong impact load resistance: when low concentration wastewater is treated (COD=2000 ~ 3000mg/L), the circulating flow rate in the reactor can reach 2 ~ 3 times of the water inflow. In the treatment of high concentration wastewater (COD=10000 ~ 15000mg/L), the internal circulation flow can be up to 10 ~ 20 times of the incoming water.
> Strong resistance to low temperature: due to the large number of microorganisms in the NPEIC anaerobic reactor, the influence of temperature on anaerobic digestion is no longer significant and serious. Usually NPEIC anaerobic reactor, anaerobic digestion can be (20 ~ 25 ℃) under the condition of normal temperature, so that reduce the difficulty of digestive insulation, save the energy.
> the alkalinity of COD conversion can be used to buffer the pH, so that the pH in the reactor can be kept in the best state, and the amount of alkali input into the water can be reduced at the same time.
> Powerful internal automatic circulation, after normal operation can shut down the external circulation system, saving power consumption.
> Good water stability: secondary UASB series and stage anaerobic treatment can compensate for the adverse effect of high K s in the anaerobic process. It has been proved that reactor fractionation can reduce the VFA concentration of effluent, prolong the biological residence time and stabilize the reaction.
> Short start-up cycle: the sludge in the anaerobic reactor of NPEIC has high activity and fast biological proliferation, which provides favorable conditions for the rapid start-up of the reactor. The start-up cycle of NPEIC anaerobic reactor is generally about 7 days, while that of ordinary UASB is as long as 4 ~ 6 months.
> High utilization value of biogas: stable biogas production, high yield, 045 ~ 0.5m³/kg COD, heat value =1kg standard coal,1.5 KWH electricity /m³ biogas. The purity of biogas produced by NPEIC anaerobic reactor is high, with CH4 being 70% ~ 80%, CO₂ 20% ~ 30% and other organic matter 1% ~ 5%, which can be used as fuel.