Do we need Ozone or UV to treat the outbound effluent ?
Both the Ozone and UV systems are expensive for any large volume treatment process.
Unless a very critical Synthetic Organic Compound (SOC) or critical COD are needed to be taken out or broken down, where those systems provide for Advanced Oxidation Process (AOP) or Photo-chemical Oxidation with or without Hydroxyl (OH) radicals providing agents like Hydrogen Peroxide (H2 O2 ) , investment for those systems are not viable.
If the unit is releasing the effluent to the agricultural stream then our MF / UF polishing filters are giving enough bacteria and virus log reduction to be further boosted with either UV or Ozone.
If the Mill is reusing the water in the boiler, then it will be even less needed when they finally convert it as steam and hence microbial population in their source water makes no practical impact in production standard.
Finally the client decides what quality of water they are going to reuse in their production process (soaking or wet milling) and if they require Ozone or UV systems, we can include them in our design.
In case coagulation is needed to facilitate separation of Suspended Solids (SS), we mostly use organic chemicals.
Whatever we use , we select GRAS (Generally Recognised As Safe) certified chemicals, so that the sludge is usable at least up to the standard of animal feed.
Sedimentation or Floatation
Sedimentation of flocculated particles needs more foot print, larger tanks, longer batch times.
It is only recommended where there is a small daily flow.
Floatation can be made continuous if needed and involves less foot print and initial investment in case of larger daily flow.
It is easier to tackle larger flows with floatation.
Use of Filter Press/Centrifuge/Hydrocyclone for sludge dewatering or separation
Hydrocyclone is used to separate the flocculated sludge during the automated process and the cleaner water goes for further treatment.
The separated sludge slurry can now be further dewatered using filter press or decanter centrifuges, if it is not composted.
If the sludge is not containing organic matter it can now be disposed of in a landfill, if it is not containing any toxic waste.
If the sludge is rich in organic matter then it can be mulched and made into compost as means of disposal at a nearby location or onsite.
There is no point in investing in equipments and further large electrical energy usage to dewater or compress such a sludge and further transport it to dumping pit, where it will be composted anyway.
We, in our design intend to pump the wet sludge into composting pit, where it will be further decomposed using utilizing a specialised proprietary consortia of microbes.
The resultant compost will be richer in nutrients.Only when there is no scope for on site composting and the sludge needs to be taken out to a distant disposal ground, to reduce the volume of wet sludge, those equipments are deployed.
Why we choose Aerobic Process rather than Anaerobic Process:
Methane is produced in the anaerobic process, thus the aerobic process is much greener.
Producing gas and thus recovery of energy from wastewater had been the key slogan in favour of Anaerobic process until now.
Recent developments around the world has shown that even in the aerobic process by using microbial fuel cell, production and recovery of energy potential from wastewater is much more viable. Commercialization of the process is already underway in USA, CANADA etc.
When that technology comes to market, we want our present clients to adopt the technology, as that will bring even better cost-effectiveness in their operation of the wastewater treatment plant.
The main disadvantage of aerobic treatment is the energy cost of aeration at an adequate rate to maintain the dissolved oxygen levels needed for aerobic bacterial growth and functions.
Use of proper blend of micro-organisms has enabled us to reduce the time needed to break down the pollutants, thus minimizing the need time needed for the process.
Use of advanced designs of our aeration equipment made them many times more energy efficient than earlier.
At whatever the apparent cost, the aerobic treatment is greener and sustainable than anaerobic process and hence the total cost is much less while taking environmental consideration into account.
Our design criteria is always future inclusive.
When we design a plant, we incorporate best of present day available technology according to the need of the project, considering the financial and practical capability of our client.
At the same time we look around to see what could be the future of technology in that segment and their key features, so that when it will be available ,our designed plant can easily adapt them without much difficulties or financial stress to our clients.
We deploy technology and product with possible relevance at least for the next 10-15 years.
Controlling microbial population in effluent at the discharge outlet of the plant
Looking at the final use of the treated effluent we decide upon the degree of filtration we need in our design. We provide MF or UF hollow fiber membranes in cross flow, practically using them as stand alone Membrane Bio Reactor (MBR) formation in our systems, according to the needed specification to filter out bacteria and viruses with 2-6 log according to need.
If need be, activated carbon filtration is added to the system upon demand as further back up, which also takes out Chlorine, VOC, SOC.