31results about How to "Improve noise pollution" patented technology

The invention provides a sound absorption wall which comprises an outer layer a, a center layer and an outer layer b. The sound absorption wall has a good sound insulation effect and is simple in structure, light in weight, high in construction speed and wide in application range.

The load control method for ball mill in powdering loop cement plant adopts a double-layer control structure, including an upper layer of self optimizing algorithm and a lower layer of multidimensional fuzzy control algorithm. The self optimizing algorithm finds out the optimal inside material storage quantity inside the ball mill as the controlling set value; and the multidimensional fuzzy control algorithm controls the material compounding links to realize the automatic regulation of the material feed quantity, so as to reach the required components in the cement production, lower the raw material amount and the cement screen residue, raise grinding fineness, ensure cement quality, increase output of ball mill and lower production cost.

A waste heat recovery system for a vacuum moisture conditioner, including a condenser and a circulating water tank, the lower part of the condenser is provided with a steam inlet, a condensed water outlet, a circulating water inlet, and a circulating water outlet, and the condensed water outlet and the circulating water outlet are connected through a pipeline. The circulating water tank is connected, the circulating water inlet is connected with the circulating water tank through a circulating pump, the circulating water tank is provided with a cooling pipe, and the condensed water outlet is connected with the cooling tube through a pipeline. The invention starts from reducing the tube resistance of the heat exchanger and improving the heat exchange efficiency, and conforms to the characteristics of instantaneous, intermittent and large flow of the residual steam discharged by the steam ejection of the jet vacuum humidifier, and uses the radiator as a steam residual steam condenser With structural design, it can be used as a supporting product for this type of vacuum conditioning machine.

The invention proposes a closed cavity type PVDF thin-film loudspeaker. The closed cavity type PVDF thin-film loudspeaker comprises a main structure and an impedance converter; the main structure comprises a PVD thin film, a sound absorbing material layer and a glass fiber reinforced plastics back cavity; the PVDF thin film has double-sided electrodes; the double-sided electrodes respectively leadout external electrodes; the PVDF thin film and the double-sided electrodes are subjected to insulation encapsulation, and parts of the external electrodes are exposed during the insulation encapsulation; an open surface of the glass fiber reinforced plastics back cavity is a cambered surface with a rectangular projection, and the PVDF thin film after being subjected to the insulation encapsulation is sealed and fixedly connected with the edge of the open surface of the glass fiber reinforced plastics back cavity through a sealant; the sound absorbing material layer is fixed inside the glassfiber reinforced plastics back cavity body, and the sound absorbing material layer is not in contact with the PVDF thin film; and the main structure is connected with an external standard power amplifier through the impedance converter. The closed cavity type PVDF thin-film loudspeaker provided by the invention can effectively improve the sound radiation efficiency of the PVDF thin-film loudspeaker and reduce the sound radiation behind the PVDF thin-film loudspeaker, so as to solve the problems of the driving difficulty of the PVDF thin-film loudspeaker, the poor low frequency effect and the noise pollution behind the loudspeaker.