Maxi Rotor KD 31

Maxirotor Model KD 31Maxirotor Model KD 31In the past 30 years Danish Wastewater Equipment A/S has acquired a wide experience in sewage treatment. Our company has demonstrated, both with the local authorities and the manufacturing industry, that we can be relied on for sewage treatment.Sewage treatment plants world-wide have different aeration systems. There are different types and functions of aeration systems resulting also in variations with regard to efficiency and investment costs.The Maxirotor Type KD 31, which is a surface aeration system, is one possibility to achieve efficient oxygen supply in sewage water.The advantages are - A strong and simple construction - A long working life - Simple operating methods - Low service and maintenance costs - Low energy requirementsThe Maxirotor KD 31 is available in four lengths and with single or two-speed gear motors. The gear motor is a compact, oiled motor and is equipped with an equalising reservoir. The output shaft is provided with mechanical shaft seal. It is connected to the rotor shaft via a flexible torque coupling with rubber insertion. The coupling evens out peak loads during start/stop and absorbs vibrations from operation.The rotor shaft is manufactured from St.52-3 which is surface treated with 3 layers of epoxy paint in order to obtain optimum corrosion resistance. Furthermore, end plates are fitted at both ends in order to prevent splashing on gear motor and end bearing. Blade material is either hot-galvanised steel, stainless steel or plastic according to customer requirements. The blades are mounted on a rubber layer in order to protect the surface treatment of the rotary tube. At the opposite end of the gear motor, the rotor shaft has oiled roller bearings that are built into a strong bearing housing. The bearing housing is equipped with an oil filling pipe with oil gauge and drain screw. The shaft from the bearing housing is fitted with mechanical shaft seal.All bearing housing parts are easily interchangeable including mechanical shaft seal. Seals and bearing are all standard parts, type SKF or similar.The above picture shows rotor blade material qualities. Shown from left to right are hot-galvanised – stainless steel (AISI304) – acid-resistant (AISI316) – and glass fibre reinforced plastic blades.In co-operation with leading gear manufacturers, KD rotor standard version can be delivered with either UNIMAX gear from Desmi A/S (Denmark), or with block gear from Nordgear (Germany). Both gear types are specially made for operation in an extremely aggressive environment to meet the strict demands for surface treatment and shaft seals. Motors can be delivered as one or two speed motors at your request. Standard motors are delivered with standstill heater and thermal sensor. Gear and end bearing have been given the same surface treatment as the rotor shaft. Submersion (cm)Power consumption (kW/m rotor)10 12 14 2422201816 282612345678910Submersion (cm)Oxygen output (kg O2/m rotor/hour)10 12 14 2422201816 282612345678910Type Effective length Number of blades Power (kW) Torque (Nm) Rotor (rpm)KD 31-4500 S 4.5 m 360 22 2883 73KD 31-4500 D 4.5 m 360 16 / 23 3165 48 / 73KD 31-6000 S 6.0 m 480 30 3928 73KD 31-6000 D 6.0 m 480 20 / 30 3951 48 / 73KD 31-7500 S 7.5 m 600 37 4828 73KD 31-7500 D 7.5 m 600 24 / 36 4738 48 / 73KD 31-9000 S 9.0 m 720 45 5872 73KD 31-9000 S 9.0 m 720 55 7195 73KD 31-9000 D 9.0 m 720 30 / 45 5887 49 / 73www.dwe.dkAccessoriesA sound absorbing cap reduces noise from the gear motor. It consists of a steel frame lined with a glass fibre plate and is provided with holes for airing of motor. On the inside, the sound absorbing cap is insulated with special sound absorbing plates manufactured from a synthetic material.Guide plates force water current and oxidation downwards enabling oxidised water and air bubbles to mix with the subjacent water. The guide plates are made of pressure treated wooden planks mounted on galvanised steel fittings.An aerosol shield made of fibre glass enables encapsulation of some of the aerosols that are liberated by air bubbles rising to the surface after the rotor. An aluminium cover is used on the ramp over the Maxirotor. The cover consists of prefabricated cassettes with non-skid floor plate surface.The oil pump KD31-OP facilitates regular change of oil considerably. The oil is pumped out of the gearbox and the end bearing by means of a suction pipe. The oil is then pumped into another container thereby avoiding oil slick and oil pollution. The pump is operated by pressure air and power supply is, therefore, not required as the pump can be operated by e.g. a mobile compressor. All parts are manufactured from oil-resisting steel.05.2011 GB