Chempure Technologies Private Limited

The Chempure upflow anaerobic sludge blanket systems or UASB systems is ideally suited to treating industrial wastewater containing medium to high concentrations of soluble organics (ie BOD in excess of 1000 mg/L). This anaerobic process requires very little energy (no aeration) and by virtue of its biogas generation is, in fact, a net energy producer. Carbon is largely converted to methane and carbon dioxide, resulting in virtually no net sludge production.

The upflow anaerobic sludge blanket systems design has been developed on a modular concept where the digestor size can be expanded to any size based on the Geometry of the Pilot Plant. The design has been successfully adapted for various liquid effluents like Sugar Factory, Distillery, Dairy etc.

The upflow anaerobic sludge blanket systems settlers as well as the roof are in modular construction and the same can be completely fabricated in the manufacturing shop and assembled at site giving necessary dimensional tolerances as well as ensuring quality construction.

DISSOLVE AIR FLOTATION - Water Treatments

The removal of small particulate matter and oil droplets, for which gravity separation can be extremely slow, requires an alternative process. A method which can be considered in these circumstances is air flotation.In this process, small bubbles of dispersed air are released into the contaminant, attach themselves to the solids or droplets and rise to the surface, taking the contaminants with them.

PERFORMANCE

Typical figures for oil, suspended solids and COD removal would be:

oil removal	80-90%
suspended solids removal	65-75%
total COD removal	60-70%

These figures apply to a feed material containing approximately 50 ppm of oil and with influent CODs in the range of 1000 to 10,000 ppm and SSs in the range of 50 to 400 ppm. At lower feed concentrations the performance expressed as a recovery rate is usually much lower.

 A DAF is typically installed after a primary screen. The DAF removes the smaller particulate that pass through the screen. A DAF operates on the following principle of pressurizing the water with air to increase the air saturation into the water. The water then flows across a backpressure valve (the pressure is relieved), thereby allowing the air to come out of solution (effervesce) out of the water. This is the same reaction that happens when you open a 7-up bottle and the bubbles come out of solution causing the bubbling. The micro bubbles produced in the DAF adhere to the small particulates in the wastewater. Once the bubble and particle adhere, they quickly float to the surface of the DAF where they are scraped off as a sludge.

DAF's have a removal efficiency of up to 95% TSS & 60% BOD,  depending on the waste stream particulate and the chemistry  involved. Polymers greatly enhance this performance and can yield  a higher percent solids in the sludge

FLUIDISED BED BIOREACTOR

Chempure developed the in-house state of the art fluidised bed bioreactor CHEMPAC FBBR  which can be used for any type of process wastewater and municipal wastewater achieving high efficiency. It offers features like, quick start up, self cleaning, fully automatic once in operation, automatic sludge separation, and "mess free" robust operation with central up-front control, systems for both sewage and industrial wastewater. 


The process

The heart of the Fluidized Bed Bio Reactor (FBBR) technology is a proprietary media and a unique air distribution system. This media provides a large protected surface area for biological attached-growth. In the FBBR tanks and reactors, the media is subjected to an aeration process for maximum oxygen and mass transfer. The result is a very high rate of Biochemical Oxygen Demand (BOD) reduction per volume. The high density of attached living biomass makes the process much more resistant to toxic shock, sludge bulking, and other problems that can plague pure suspended growth systems. Chempure FBBR technology allows for biological treatment in much less time and space required than for conventional biotreatment systems currently utilized. A typical configuration is depicted below. Air generated from air blower is diffused into the bottom of the reactor vessel. The oxygen supply is automatically adjusted to maintain the proper dissolved oxygen level in the vessel. A high concentration of biomass develops because of the large media surface area, abundant oxygen and optimized mass transfer conditions. Excess biomass is automatically sheared at the discharge point for removal.

BENEFITS

• compact design.
• high throughput-to-size ratio
• 95% BOD reduction achievable
• low operator attention
• low capital and operating cost, and virtually odor-free
• Can be customized to your requirements
• Easy and quick installation
• Continuous uniform growth of biomass
• Continuous uniform sloughing of excess biomass
• Continuous uniform liquid distribution
• 1High hydraulic capacity and durability
• Resistant to clogging
• Eliminates dead spots

The Chempure Reactivator Clarifier is a well-established waste water treatment process for effective and efficient removal of suspended solids and other physical contaminants from wastewater.   It is a high rate clarifier, which, in minimum time and space and using a minimum of chemicals, produces an effluent of highest quality.   It is principally used for coagulation, flocculation and clarification of water and waste water containing suspended solids, colour and organic impurities

Coagulants such as ferrous sulphate, lime and polymer are added for effective precipitation.  The reactivator clarifier waste water treatment solution is designed to ingeniously combine flash mixing followed by slow speed agitation and settling in one central zone whereby reducing retention time as required for conventional clarifier.  This results in effective reduction in the equipment sizes as well as substantial savings in the utilization of treatment chemicals.

FILTER PROCESS

• Manual operation
• Cumbersome to operate and maintain
• Short cycle operation
• Low moisture content
• Not suitable for biological sludge

CENTRIFUGE DECANTER

• High rate of filtration
• Continuation operation
• High moisture  content
• Automatic operation

Chempure offers effective sludge thickeners for thickening the bio sludge form the secondary water treatments. The consistency of the sludge is increased to the maximum thereby reducing the load on the downstream dewater plants such as centrifuge/filter press.

Thickeners is accomplished in a simple circular sedimentation tank. Dilute sludge is fed to the center-fed well. The feed sludge water treatments is allowed to settle and compact, and the thickeners sludge is withdrawn from the bottom of the tank. Conventional sludge collecting mechanisms with deep trusses or vertical pickets are used to stir the sludge gently, thereby opening up the channels for water to escape and promoting densification. The supernatant flow that results is returned to the primary settling tank. The thickened sludge that collects on the bottom of the tank is pumped to the digestors or dewatering equipments.

UPFLOW ANAEROBIC SLUDGE BLANKET SYSTEMS

The Upflow Anaerobic Sludge Blanket Systems also relies on upflow velocities to suspend anaerobic solids. However, upflow velocities are much lower than utilized in the AFB process since no carrier material is provided. Instead the anaerobic active mass tends to form a granular type of sludge which assists with its retention in the anaerobic reactor. Various differences between UA Sludge Blanket Systems reactors were noted on visits to various European facilities. Some reactors are constructed of concrete; others of steel. Some reactors are rectangular; others are cylindrical. Some are moderate height (6 m ); one extended 20 m high. The reactors generally had various proprietary designs for distributing influent and recirculated flows at the bottom as well as three-phase (effluent, solids, gas) separators at the top.

 

AREA OF SLUDGE BLANKET APPLICATION

The UA Sludge Blanket Systems concept which has been traditionally used for treatment of liquid effluents has been successfully modified for treatment of liquid waste with high concentration of suspended solids like Abattoir waste waters as well as solid waste like Poultry droppings, Kitchen Waste, Vegetable Waste.

LOADING RATES

Type of Wastewater	Maximum loading rate (kg COD / m3-day)	COD Reduction (%)
Sugar beet factory	30-32	75
Potato Processing	40	84
Potato starch production	30	75
Vegetable canning	10-20	60-80
Yeast factory	14	70
Dairy factory	15	80
Slaughter House	10	55
Rendeering plant	6	63
Distillery waste	11-17	45-65
Wood ethanol stillage Currant finishing	16	86
Wastewater	10-12.5	93-95