Enviro Engineering

Thirumudivakkam, Chennai, Tamil Nadu

Our company is reckoned amongst the trustworthy providers of an unmatched range of High Rate Solid Contact Clarifier. Our clarifier is a high rate recirculation type clarifier that is used for the purpose of clarification, silica reduction, lime softening or organics reduction of water and wastewaters containing suspended solids, color and higher clarified water quality. It also increases the over flow.

clariflocculators are much useful in the primary treatment of water. our company provides products that benefit the environment and its inhabitants. clariflocculators are generally used for chemical primary treatment for effluent. instead of separate flocculation & clarification, clariflocculators are generally used. this results into economical and faster installation of primary treatment. our clariflocculators have high torque center drive with sludge arm lifting device. main feature of our clariflocculators is concentric paddle type flocculator mechanism which creates the flocs throughout the flocculation zone.
we can provide the skimming mechanism or skimming device, if required by the clients for particular applications. generally, this mechanism is required to remove floating debris, solids, which float on effluent surface. it compromises of rotating skimmer, scum scraper and scum box. neoprene rubber wipers are generally provided with the clariflocculators. the scum scraper collects the scum and drops it in scum box, which is connected to withdrawal piping. a scum skimming arm, supported on one of the scrapper arm is provided for removal of floating debris or solids. the collected scum is pushed by a level-loaded or spring loaded scraper into a scum box. through this scum box the scum drains off the paddle and pipe. thus, floating scum is taken out from the clarifier easily.

Water Clarifier that we offer is widely used for chemical effluents, various types of industrial processing & even metallurgical processing, where the efficient separation of solids from liquids is required. Efficient separation of suspended solids or sedimentation is an important and essential aspect in effluent treatment, since it not only reduces considerably suspended solids loading, but also helps in reducing the COD / BOD loading, thereby contributing in reducing the sizing of subsequent process viz. that of Biological treatment, etc.
Thus, clarification or sedimentation, the process to remove suspended solids, is economical and has become an essential part of effluent treatment plants and raw water treatment plants. Our Water Clarifier removes suspended solids up to 70% and settles able solids removal up to 90% to 98% and COD removal as high as up to 40% are achievable with proper design of the clarifier unit. The process is purely of gravity-separation. This is achieved by the reduction in velocity of the fluid and nearly 180o change in the direction of the flow. The separate solids would flow downward and settle on tapered floor.
The slow moving scraper mechanism having scraper arms with neoprene rubber / PP / HDPE / Brass squeegees, scrapes the floor and brings the settled sludge (suspended solids) to the central sludge well. The velocity or the movement of scraper arms and squeegees are designed in such a way that the sedimentation process is not distributed at all.

Comparison Between End Drive / Centre Drive Clarifiers :There are two basic types of the clarifier mechanisms which are manufactured. 1) End Drive / Traction Drive type Clarifier with central RCC column for support. 2) Centre Drive Clarifier. Even though we manufacture both types of Clarifiers at our workshop (having 40, 000 sq.ft. area), we recommend Centre Drive Clarifiers to the clients due to the following reasons :

• There are two scraper arms in Centre Drive type as compared to one scraper arm only in End Drive type. So, the floor is scraped twice in one revolution of Centre Drive Clarifier, while in End Drive Clarifier the floor is scraped once only (as there is generally only one hanging scraper arm). Hence scraping efficiency is high in Centre Drive Clarifier.
• Centre Drive Clarifier has low running/operating costs, & hence is more economical. For the same diameter of the Clarifier, the HP required for the End Drive Clarifiers is more than HP required for Central Drive Clarifier. For example, in 10 to 15M dia; the Centre Drive Clarifier the motor is of 1HP-1.5HP, while End Drive Clarifier motors are never less than 2HP-3HP. So, there is saving in Energy Charges.
• Centre Drive scraping is 'POSITIVE TORQUE' scraping, while in End Drive, since the scraper is hung from the travelling bridge, the factors for the scraping force i.e. the weight of scraper arm and frictional force between the wheel and the end wall top, are too low & becomes zero when the wheels start slipping on the wall.
• From the maintenance point of view, there are more wearing parts in End Drive Clarifier and hence it results in more maintenance expenditure and sustained prolonged down times.

Having more than thirty years of manufacturing experience in effluent treatment plant machineries and having full-fledged Research & Development Department attached with hydraulic testing facilities up to 150 HP Aerators & having manufacturing facilities of total 40, 000 sq.ft. area, we have developed & incorporated following essential cum efficient features in our Clarifiers.

Special Features:

• High Torque 'ENVIRO' Centre Drive with gears is designed for achieving high scraping efficiency with additional Greaves gears to achieve High reduction ratio.
• Scraper arms lifting devices in two varieties: a) Hand Operated Scraper Arms Lifting Devices: This is our standard in-built feature in clarifier. This is provided at no extra cost. When the scraper arms are embedded, in sludge, due to prolonged stopping of the clarifier, the clarifier mechanism cannot be restarted. The motor will trip, the scraper mechanism gets twisted up and drive gets overloaded and damaged. In such cases the effluent has to be pumped out and settled sludge has to be removed to restart the mechanism. While in our Clarifier there is no such issue. Operator has to come on the platform and has to operate the hand wheel. Both the scraper arms are lifted to a maximum height of 200mm. Then the mechanism can be switched on the scraper arms can be lowered down slowly by operating handle in reverse direction. b) Motorized Scraper Arms Lifting Device: Only 0.5 HP extra electric motor and gearing operate the lifting of the scraper. This feature is provided by us at an extra cost.
• Fixed type full span bridge of Lattice structure suitably designed to take required torque, and having least linear deflection. Also, one meter high double row hand rails are provided.
• Suitably designed center drive rotates the heavy mild steel tubular central pipe, having two scraper arms with neoprene rubber / HDPE / PP / BRASS squeegees.
• Central sludge well scraper.
• Overload protection & lifting devices: Electro-mechanical overload protection device has load indicator, Hooter alarm and drive motor cutout switches. In addition to this unique feature particularly for thickeners, motorized semi-automatic or automatic scraper arms lifting devices are also incorporated by us on clients demand. Hand operated scraper arms lifting device are provided with all ENVIRO clarifiers & thickeners as a standard feature.
• Offering polypropylene (P.P.) intake well as standard feature.
• Enviro Clarifiers is available without bottom sludge withdrawal pipe. The sludge at 5 to 10mt. total head (pressure) can be obtained at the end of the platform simply by pipe flange connection, this can be taken either to sludge drying beds or to aeration tanks for activated sludge plants.

Advantages :

• Relief from the frequent maintenance of chocking bottom sludge pipe
• No separate buying and installing of sludge recirculation pumps
• No special construction R.C.C. dry sump for pump

The High Rate Sludge Contact Clarifier (HRSCC) that we provide is designed to remove the suspended solids and high turbidity in the water. This system contains clarifloculator tank along with clarifier that comprises lamella type, tube settler or convectional clarifier. Our High Rate Sludge Contact Clarifier has the ability to offer turbidity less than 50 NTU at the outlet of clarifier.    The solid contact clarifier is widely used for treating raw water and waste water; producing clarified water of highest quality. Our High Rate Sludge Contact Clarifier can be used for applications such as pretreatment of surface water source and applications in municipal supply treatment plants, ETPs and STPs. It can also be used for floriculture, agriculture and horticulture farms, sugar factories, fertilizers, chemicals, textiles, power plants and in applications where large capacity is required.

Applications :

• Clarification of surface water
• Lime soda softening
• Removal of colloidal silica
• Colour removal
• White water recycling
• Primary (Physico –chemical) treatment of waste water
• Removal of heavy metals in the chemical and automobile industries

Principal Of Operation : The solid contact clarifier works on two basic principles of coagulation / flocculation and hydraulic separation. Coagulation and flocculation occur in the flocculation zone when the feed stream comes into intimate contact with chemical mixtures and suspended sludge particles from previously treated water. This contact also promotes floc growth as smaller particles agglomerate into larger heavier particle. The hydraulic separation principle uses an up flow design to move water into the settling zone for clarification.

Lamella Clarifier is primarily used in the water and wastewater treatment industries to separate solids from liquids in effluent streams. The clarifier is the third step in what is usually a four step process for water and wastewater treatment. In wastewater treatment the four main steps are collection and homogenization of effluent, pH adjustment, clarification and sludge dewatering.
Conventional clarification equipment requires a much larger surface footprint in order to match the solids removal capacity of a Lamella Clarifier. This is accomplished because the effective gravity settling area of the inclined plate design is proportional to the total surface area of the inclined plate rack. Loading rates normally used for the design of conventional settlers can be applied to the sizing of a Lamella clarifier or settler by substituting projected area for the surface settling area of a conventional clarifier.
The compact design of this Lamella Clarifier essentially eliminates any hydraulic disturbances caused by wind or temperature changes that may be problematic with conventional clarifiers located outdoors. Balanced flow distribution ensures equal flow to each plate and across the plate surface area, preventing short-circuiting. Units and plate packs arrive at the job site factory assembled which reduces installation time while cutting down the installation costs. Minimal moving parts mean low maintenance costs.

Operating Principle : Our Lamella Clarifier with a series of inclined plates are arranged to form a separate sedimentation chamber between adjacent plates. Raw water is first fed to Static Mixer and chemicals such as alum, poly electrolyte are added prior to static mixer for proper mixing of chemicals in water. Water from static mixer enters in Flocculator in which paddle type agitator is provided for gentle mixing. Polymer is added for flocculation of coagulated particles.