We are offering effluent treatment plant ( waste water treatment ).
water & waste water treatment systems & solutions
our environmental impact on the earth has exceeded the planets life sustaining abilities as well as its self recovery capabilities. Komal understands the need to integrate the process plant, with economical & efficient water & waste water management systems & solutions for your metal finishing & industrial applications.
we are truly a one stop source for plant automation with built in value added pollution control, resulting in multiple benefits including compliance with pollution control laws & regulations, along with optimization of capital investment. Be assured to get perfect solutions that work, from a friendly, knowledgeable team who are honest, dependable and proven in the metal finishing, electroplating and allied industries. We are with you long after the job is done.
latest technology for effluent treatment with zero discharge & recovery
pollution control systems our product portfolio
control panels, plc automation dosing control equipments tanks for effluent collection, storage and treatment reactions tanks dosing tanks oil water separators
filter press systems clariflocculator gravitational settling clarifiers pressure sand filter activated carbon filter dm plants reverse osmosis sludge treatment - sludge dewatering , sludge dryers, centrifuges filter media pumps ( dosing pumps, centrifugal pumps, metering pumps, screw pumps, effluent discharge pumps, etc) agitators & industrial mixers blowers electrical equipments instrumentation for process control - "hanna, usa" range of water testing & treating equipments rota meters, ph, orp & conductivity meters valves - gate, globe, butterfly, diaphragm, ball , pressure release , vacuum release level switches piping systems - valves, fittings and piping in pp, pvc, hdpe, carbon steel, etc & fitting.
waste water recovery systems for plating, phosphating and pcb industry - profit through
effluent recycling waste minimization chemical recovery acid recovery trivalent chrome
purification nickel recovery carbonate removal cleaner recovery
offering superior technologies and engineering, with "simplicity of design"
waste water treatment chemicals
for effluents from
surface conditioning process
metal finishing process
acid pickling and brightening
copper plating process
nickel plating process
chrome plating process
zinc plating process
tin & tin lead alloy plating
other areas of surface finishing
hydrochloric acid sulphuric acid sodium bi sulphite ferric sulphate ferric chloride sodium sulphide quick lime polyelectrolytes sodium hydroxide others
waste water treatment consultancy
komal, as well as supplying plant and equipment, is able to offer services based on its expertise in relation to a broad range of issues. We can produce:
process and instrumentation drawings
layout drawings emphasizing the ergonomics of the plant
a diagnosis of your existing treatment plant
an improvement plan in anticipation of tighter discharge limits
areas of expertise
chemical and physico-chemical processes for the treatment of metal complexes.
zero discharge concept whenever possible.
cyanide oxidation processes.
chromium reduction techniques.
heavy metals precipitation.
evaporation (atmospheric and vacuum, heat pump and mvc).
membrane technology.
ion exchange resin.
settlement systems.
coagulation and flocculation systems.
permanent media filtration.
komal has the best designs & solutions for air pollution control also.
process description for electroplating wastewater treatment
electroplating wastewater comes from surface plating operations where the metal is dipped in an electroplating solution of various types of metals and then rinsed.
typical plating includes brass, nickel, cadmium, zinc, silver, copper, and gold. Electroplating wastewater is typically from washing, rinsing and batch dumps and is at a low ph of 3-5 and contains soluble forms of the various metals. In order to remove soluble metals from the wastewater it must first be made insoluble. The insoluble metal is then coagulated, flocculated and clarified by sedimentation.
the typical method to reduce and remove soluble electroplating metals from wastewater is as follows:
stage 1 precipitation and coagulation:
ph is raised from 3 to 8.5 with the ph controller using caustic while adding a coagulant such as ferric chloride. Testing of the wastewater may confirm that a coagulant is not needed. A pin floc is developed indicating the metal is insoluble. Some applications have plating enhancing chemicals present, emulsifiers and such that may require more sophisticated high performance coagulants to break the bonds and allow the metal to precipitate.
stage 2 - flash mix:
the wastewater with its precipitated pin floc is introduced to the flash mix zone where a polymer flocculent is added. This stage maximizes flocculent dispersion throughout the coagulated wastewater.
stage 3 - flocculation:
the wastewater is now introduced to the slow mix zone to agglomerate the pin floc into larger rapid settling particles.
clarifier, inclined plate:
the flocculated wastewater is introduced into the clarifier where the settling particles land on the inclined plates and are directed downward and into the sludge chamber. The clarified treated water then exits the top of the clarifier and flows downstream to sewer or further treatment if necessary.
clarifier sludge handling:
the resulting clarifier waste sludge is periodically removed from the clarifier at a slow rate and sent to the sludge holding tank where it further thickens and accumulates a batch for disposal or processing in a filter press.
sludge dewatering:
the thickened clarifier sludge is allowed to accumulate sufficiently to provide a full batch for the filter press. The filter press is pumped full of the sludge until it is full. The filter press is then emptied of the cake which is a semi solid of approximately 20-35 % solids. Sludge cake is high in phosphate and should be disposed of according to environmental regulations.
applications:
electroplating shops are found in typically two categories, captive and independent shops. Some industries operate their own captive, in house electroplating operation while others outsource to an independent operation.
typical industries include:
electroplating shops, captive or independent
automotive suppliers, trucks, motorcycles etc metal to rubber suspension and body parts
jewellery mfg
machine tool mfg.
metal forming such as stamped metal parts that require plating of various types.
building materials, cadmium plated nuts, bolts etc. . . .
aerospace
wire forming - nails, screws etc
appliance makers
electronics gold and silver plating of electrical connectors etc.
environmental guidelines for electroplating industry
industry description and practices
electroplating involves the deposition of a thin protective layer (usually metallic) onto a prepared surface of metal, using electrochemical processes. The process involves pre-treatment (cleaning, degreasing, and other preparation steps), plating, rinsing, passivating, and drying. The cleaning and pre-treatment stages involve a variety of solvents (often chlorinated hydrocarbons, whose use is discouraged) and surface stripping agents including caustic soda and a range of strong acids, depending on the metal surface to be plated. The use of halogenated hydrocarbons for degreasing is not necessary as water based systems are available. In the plating process, the object to be plated is usually used as the cathode in an electrolytic bath. There are three main types of plating solutions: are acid or alkaline solutions and may contain complexing agents such as cyanides.
waste characteristics
any or all of the substances used in electroplating (such as acidic solutions, toxic metals, solvents, and cyanides) can be found in the wastewater, either via rinsing of the product or due to spillage and dumping of process baths. The solvents and vapours from hot plating baths result in elevated levels of volatile organic compounds (vocs) and in some cases, volatile metal compounds (when may contain chromates). Approximately 30 percent of the solvents and degreasing agents used can be released as vocs when baths are not regenerated.
the mixing of cyanide and acidic wastewaters can generate lethal hydrogen cyanide gas and this must be avoided. The overall wastewater stream is typically extremely variable (1 liter to 500 liters per square meter of
surface plated) but usually high in heavy metals (including cadmium, chrome, lead, copper, zinc, and nickel), cyanides, fluorides, and oil and grease, all of which are process dependent. Air emissions may contain toxic organics (such as trichloroethylene and trichloroethane).
cleaning or changing of process tanks and the treatment of wastewaters can generate substantial quantities of wet sludges containing high levels of toxic organics andor metals.
pollution prevention and control
plating involves different combinations of a wide variety of processes and there are many opportunities to improve upon the traditional practices in the industry. The following improvements should be implemented where possible:
changes in process
replace cadmium with high quality corrosion resistant zinc plating. Use cyanide-free systems for zinc plating where appropriate. In those cases where cadmium plating is necessary, use bright chloride, high alkaline baths or other alternatives. However, alternate complexing agents to cyanides may cause problems in wastewater treatment for they may result in the release of heavy metals.
use trivalent chrome instead of hexavalent chrome: acceptance of the change in finish needs to be promoted.
373 374 electroplating industry
give preference to water-based surface cleaning agents, where feasible, instead of organic cleaning agents, some of which are considered toxic.
regenerate acids and other process ingredients, whenever feasible.
reduction in drag-out and wastage
minimize drag-out by effective draining of bath solutions from the plated part by measures such as making drain holes in bucket type pieces, if necessary.
allow dripping time of at least 10 to 20 seconds before rinsing.
use fog spraying of parts while dripping.
maintain the density, viscosity, and temperature of the baths to minimize dragouts.
place recovery tanks before the rinse tanks (which then provide make-up for the process tanks). The recovery tank provides for static rinsing with high dragout recovery.
minimizing water consumption in rinsing systems
it is possible to design rinsing systems to achieve 50-99% reduction of traditional water usage. Testing is required to determine the optimum method for any specific process but proven approaches include:
agitation of rinse water or work pieces to increase rinsing efficiency.
multiple counter current rinses.
spray rinses (especially for barrel loads).
management of process solutions
recycle process baths after concentration and filtration. Spent bath solutions should be sent for recovery and regeneration of plating chemicals, not discharged into wastewater treatment units.
recycle rinse waters (after filtration).
regularly analyze and regenerate process solutions to maximize useful life.
clean racks between baths to minimize contamination.
cover degreasing baths containing chlorinated solvents when not in operation to reduce losses. Spent solvents should be sent to solvent recyclers and the residue from solvent recovery properly managed (e.g., blending with fuel and burning in a combustion unit with proper controls for toxic metals).
target pollution loads
a key parameter is the water use in each process and systems should be designed to reduce water use. Where electroplating is routinely performed on objects with known surface area in a production unit, water consumption of no more than 1.3 liters per sequence meter plated (lm2) for rack plating and 10 lm2 of surface area plated for drum plating should be achieved. The recommended pollution prevention and control measures can achieve the following target levels:
cadmium plating should be avoided. In cases where there are no feasible alternatives, a maximum cadmium load in the waste of 0.3 grams for every kilogram (kg) of cadmium processed is recommended.
at least 90% of the solvent emissions to air must be recovered by the use of an air pollution control system such as a carbon filter.
ozone depleting solvents (such as chlorofluorocarbons and trichloroethane) are not to be used in the process.
treatment technologies
segregation of waste streams is essential due to the dangerous reactions which can occur: strong acidcaustic reactions can generate boiling and splashing of corrosive liquids; acids can react with cyanides and generate lethal hydrogen cyanide gas. In addition, segregated streams that are concentrated are easier to treat.
air emissions
exhaust hoods and good ventilation systems protect the working environment but the exhaust streams should be treated to reduce vocs (using carbon filters which enable the reuse of solvents) and heavy metals to acceptable levels before venting to the atmosphere. Acid mists and vapours should be scrubbed with water before venting. In some cases, voc levels of the vapours are reduced by 375 electroplating industry combustion (and energy recovery) after scrubbing adsorption, or other treatment methods.
liquid effluents
cyanide destruction, flow equalization and neutralization, and metals removal are required, as a minimum, for electroplating plants. Individual design is necessary to address the characteristics of any specific plant but there are a number of common treatment steps. For small facilities, the possibility of sharing a common wastewater treatment plant should be considered. Cyanide destruction must be carried out upstream of the other treatment processes. If hexavalent chrome (cr+6) occurs in the wastewater, then this is also usually pre-treated to reduce it to a trivalent form using a reducing agent (such as a sulphide) followed by precipitation and sedimentationfiltration.
the main treatment processes are equalization, ph adjustment for precipitation, flocculation, and sedimentationfiltration. The optimum ph for metal precipitation is usually in the range of 8.5-11 but this depends on the mixture of metals present. The presence of significant levels of oil and grease may affect the effectiveness of the metal precipitation process. Hence, the level of oil and grease affects the choice of treatment options and the treatment sequence. It is preferred that the degreasing baths be treated separately. Flocculating agents are sometimes used to facilitate the filtration of suspended solids. Pilot testing and treatability studies may be necessary. Final adjustment of ph and further polishing of the effluent may also be required. Modern wastewater treatment systems use ion exchange, membrane filtration, and evaporation to reduce the release of toxics and the quantity of effluent that needs to be discharged. These can be designed to have a closed system with a minor bleed stream.
solid and hazardous wastes
treatment sludges contain high levels of metals and these should normally be managed as hazardous waste or sent for metals recovery. Electrolytic methods may be used to recover metals. Sludges are usually thickened, dewatered, and stabilized using chemical agents (such as lime) before disposal which must be in an approved and controlled landfill. High costs of proper sludge disposal are likely to become an increasing incentive for waste minimization.
emission guidelines
emission levels for the design and operation of each project must be established through the environmental assessment (ea) process, based on country legislation and the pollution prevention and abatement handbook as applied to local conditions. The emission levels selected must be justified in the ea and acceptable to miga.
the following guidelines present emission levels normally acceptable to the world bank group in making decisions regarding provision of world bank group assistance, including miga guarantees; any deviations from these levels must be described in the project documentation.
the guidelines are expressed as concentrations to facilitate monitoring. Dilution of air emissions or effluents to achieve these guidelines is unacceptable.
all of the maximum levels should be achieved for at least 95% of the time that the plant or unit is operating, to be calculated as a proportion of annual operating hours.
air emissions
a 90% recovery of the quantity of vocs released from the process is required. 376 electroplating industry
liquid effluents
electroplating plants should use closed systems where feasible or attain the following effluent levels.
effluents from the electroplating industry parameter maximum value milligrams per liter (mgl)
ph 7 - 10
total suspended solids 25
oil and grease 10
arsenic 0.1
cadmium 0.1
chromium (hexavalent) 0.1
chromium (total) 0.5
copper 0.5
lead 0.2
mercury 0.01
nickel 0.5
silver 0.5
zinc 2
total metals 10
cyanides (free) 0.2
fluorides 20
trichloroethane 0.05
trichloroethylene 0.05
phosphorus 5
Mumbai, Maharashtra, India
