Agitated Nutsche Filter

Agitated Nutsche Filter is a closed vessel designed to separate solid and liquid by  filtration under pressure or vacuum or in combination of both. The resulting wet cake can be re-slurried and washed thoroughly with water or solvent. The discharge of wet cake is automatic. Drying of wet cake is also possible when drying features are incorporated. The closed system ensures  odourless contamination free and non-polluting working conditions maintaining product purity and hygiene. Agitated Nutsche Filters are extensively used in CHEMICAL, HERBAL, PHARMA, AGRO CHEMICAL & FOOD Industries.

Description
Agitated Nutsche Filter consists of a cylindrical shell with a welded dished end at the top and a flat welded end at the bottom. The vessel is divided into two compartments by means of a perforated plate, provided with suitable filter cloth. The base plate is having arrangement of bolting bar to hold the filter cloth. Suitable support mesh is provided under filter cloth to facilitate the flow of filtrate. An agitator of unique design and rigid and in “S” curved provided inside the vessel to perform the movements of vertical and rotational directions simultaneously, by means of push buttons switches/PLC. and to take the high torque generated during solid discharge and re-slurring operation.

OPERATION
Slurry is fed into the top compartment from where filtrate passes into the lower chamber en route to receiver. Solids are deposited on the filtering media in the top compartment and take the shape of cake of a uniform thickness. The agitator pushes the solid content in the slurry upwards by keeping it under suspension till maximum possible filtrate passes through the filter bed. It then seals the cracks in the cake, which develops after most of the filtrate has passed through, by smoothening the top surface of the cake.

Agitated Nutsche Filter Dryer also squeezes out some of the moisture in the cake by slightly pressing the cake uniformly with the help of specially designed blades. After the separation of solvent/mother liquor and if the cake requires washing, the entire cake can be re-slurried and agitated, so that all the particles forming the cake can be exposed to wash liquor and be thoroughly washed through the specially designed agitator. This improves quality of the finished products. After washing and removal of wash liquor, the cake can be discharged through a quick opening side discharge door, by rotating and lowering agitator in the discharge direction. No manual handling is required.

Process Steps

• Filtration
• Washing of Filter Cake
• Repeat mix or washing of the cake
• Convection drying of the cake
• Smoothing with compression of the cake
•  Fully Automatic discharge of the wet or dried cake.

Advantages

• The equipment is functionally safe and easy to operate.
• No manual handling.
• Through washing of cake.
• Toxic and hazardous material can be processed.
• Product purity maintained
• Blending of product possible before discharging.
• Complete automation.
• Combining filtration, washing, re-slurry and drying in a fully enclosed automated unit thus reduction of capital and operating costs.
• Large quantities can be processed faster than the conventional systems.
• Heat transfer surface can be provided on the vessel wall by providing jacket or limpet.

Spin Flash Dryer is used for effective and efficient method of removal of surface or on bound moisture from a feed product. Spin Flash Dryers are designed for continuous drying of cohesive and non-cohesive pastes, filter cakes and high viscosity liquids. Under the action of hot air and mechanical dispersion, the wet cake appears granular and gets fluidized. Instantaneous exchange of heat and mass takes place. The dried materials are taken in the collector as powder products.

The spin flash dryer system consist of double shaft screw followed by mono screw to feed homogenized material into dryer housing at controlled rate. Hot air is supplied by a temperature controlled air heater and speed controlled fan, entering the drying chamber at a tangent in order to establish a turbulent, whirling air flow. The rotor at the base of the drying chamber fluidizes the product particles and dispersed using the heat from the air stream, the material dries as it is conveyed. Drying takes place in a matter of seconds. The particle classification orifice on the top of drying chamber allows finer product to pass with exhaust gas to powder collection system while the larger particles remain in the air flow for further drying and powdering. Elevated drying temperatures can be used with many products since the flashing off of surface moisture instantly cools the drying gas without appreciably increasing the product temperature. A simple Flash Dryer is also designed to handle materials that can be suspended directly in air, requiring removal of free moisture.

Salient Features :

• High drying efficiency and low energy costs.
• Direct drying and no initial diluting.
• Continuous processing with short drying time.

Fields of Application :

• Agro chemicals
• Ceramics
• Food & Feed products
• Organic Chemicals
• Pharmaceuticals
• Pigments & dyestuffs.

Capacity Available
Up to 5 tons/hr. and the drying chamber size from 200 to 1600 mm diameter.

Material of Construction
SS & MS

Note

• Moisture evaporation is the maximum moisture evaporation volume measured when the air temperature is 180 decree C. and the discharge air is 80 decree C.
• The max. height and the floor coverage will be laid according to the actual condition. The data in the table is only for reference.

NSI Equipments Private Limited manufacture ROTARY AUTOCLAVE for reclaimed rubber industry for high temperature and high pressure cooking of rubber crumbs and to to recycle the same in to Rubber sheets in subsequent process.

The Rotary Autoclave is made from boiler quality plate with limpet coil for heating and with hollow agitator with blades, driven by motor and gear box.

These Rotary Autoclaves are designed to work at a pressure of 300 psi. and at a temperature of 250°C.

Agitator : Fabricated from seamless pipe & two end stubs of EN-8 are welded at both ends. The shaft is machined in assembly. Suitable keyways and seat is provided to seat the flanged hub accurately. The arms of the stirrer are welded to the hubs, which are keyed and bolted to the central shaft. The hub is flanged to the central shaft in two halves. The arms are welded with end blades. These blades are specially designed in a way that they turn and move the material longitudinally so that the same particle do not remain in contact with surface for long time & uniform heating is provided to the material inside.

Top & Bottom Mouths : Steel casted and specially designed, consist of jaw arrangement through which the mouth can be locked & unlocked by a suitable gearing arrangement at top and at bottom with a counter weight and gearing arrangement for easy open and for tight closer. Suitable neoprene runner gasket of single piece is mounted to the mouths to seal the system.

Capacity : Various models are available in capacity 2000, 3000, 3500 & 4000 kgs/batch.