we have to stop using chemicals to treat our waste water. there are better and greener technologies that can treat nutrients. and even recover nutrients . many options out there.
we have to stop using chemicals to treat our waste water. there are better and greener technologies that can treat nutrients. and even recover nutrients . many options out there.
Milk processing,paper mill and pharmaceutical are waste streams typically treated by trickling filters.
Discharge quality requirements are getting tighter and land is getting costlier,and there's a greater case for an additional premium on activated sludge,making it perhaps getting graded down via a vis trickling filters,membrane bioreactors
Hi Lara. What effluent standard is required? From the information you have provided, both activated sludge or biological filters could be used. If a relatively low level of treatment is required, filters provide a low energy opex option.
Activation: a function that has nothing to do with the problem of sludge. It serves only to defuse the methanization activation of the medium. At the very beginning the concrete tanks were cracking, the concrete disintegrated under the effect of the putrefaction of the medium. The rotating arm removes the effect of strong metanization
Mud
In biology, mud is the ultimate stage of destructuring of organic matter. The only natural tool that eliminates mud is putrefaction. Incompatible with the action of aeration
hello Lara. yes there is a practical tool. use Net Present Value. at the end of the day, the lowest total cost over 30 years is best. its waste water. Capital cost, yearly repair and maintenance cost and daily operating cost including everything that affects your EIA. air quality, noise pollution and discharges.
as for N and P, you live in the EU and thats part of the local requirements.
the main process is aerobic biological treatment, the sludge needs to be furthur digested and turn into a furtilaizer, be aware to hormones and medication in the waste stream , also fats can ruin the procees.
Hi all! I added a file with the characterization of the wastewater of 3 different points of the drainage network and the discharge limits by law. The points 2 and 3 are on highly obstructed areas, so maybe not that representative. The treated wastewater will be discharged on a river, and is close to reach the ocean. The land is abou 6000 m2 and te wastewater is tottaly domestic, urban. I think that will be important to remove N from my evalluation, will it be better an oxidation ditch or anoxic/aerated tank? Thank you all for your feedback!
The choice of treatment process depends upon the volume to be treated, available space, costs of construction and quality of the discharge required. - it depends on the price/availability of land. If there is insufficient land for activated sludge, or if the discharge quality requirements are so tight that it makes economic sense, processes like membrane bioreactors are used, but at the expense of higher capital and operating costs.
Some cheaper operations are following
Trickling Filters,
RBC
Activated sludge is also better if there is a requirement to remove nitrogen from the wastewater, since trickling filters can't provide the anoxic conditions needed to remove nitrates. Constructed wetlands are treatment systems that use natural processes involving wetland vegetation, soils, and their associated microbial assemblages to improve water quality. These systems can be used commercially for efficient biological treatment of wastewater, and it will also act as a better eco-friendly method when compared with other conventional treatment methods. Natural wetlands, marshes, swamps, and bogs play an important role in protecting water quality. Constructed or artificial wetland systems mimic the treatment that occurs in natural wetlands by relying on plants and a combination of naturally occurring biological, chemical, and physical processes to remove pollutants from the water. Because constructed wetland systems are designed specifically for wastewater treatment, they typically work more efficiently than natural wetlands. Some constructed wetland system designs can closely resemble natural wetlands enough to provide additional habitat areas for many birds, animals, and insects that thrive in wetland environments.
I'm not aware of a particular tool and nutrients are important. You have to start in reverse. You have to know what are the discharge limits you are allowed to discharge at and is it based on an absolute or a centile discharge. Once that has been established, you have to establish the space, which is available, the capital and the peak flows, which your plant is able to deal with. The nutrient level could also be misleading because the nitrogen needs to be split into ammonia nitrogen and total nitrogen, which is the ammonia nitrogen and other nitrogen and is the phosphate in a combined form or free phosphate. The other main question is what is the source of your effluent? A simple plant for a hotel or housing estate could be different from a plant with industrial or food wastes. Once that has been done, then you can start talking to specialist designers of effluent plants. So the COD or BOD of the waste will need to be known. Another need to know is whether there is a fat oil & grease (FOG) content.
The basic principles are screening first then look at other processes.
As per Gareth's comment below, footprint is a major factor in selection of a technology. If you have land available then the low OPEX cost of a constructed wetland and reed bed system will work in developing countries with limited energy to power conventional MBBR or SBR designs. Engineered wetlands (wastewater) and reed bed (sludge) provide an ideal solution where pristine effluent is desired and a biosolids is created that has beneficial reuse for agricultural activities.
Hi Lara! After determining the influent characteristics, you have to determine the foorprint for the design. In our case, some places here have small foorprint and would be impossible to employ a full SBR technology. We usually employ MBR. If the waste is combination of domestic and septic, you might want to have an oil separation process then ABR (Anaerobic Baffled Reactor) or Anoxic, then equalization lastly MBR. If high COD, employ a clarification system before the biological process
If you sufficient land that is inexpensive enough, another great option is land treatment. Google Muskegon County Wastewater Management System for details of a 40 MGD plant in Western Michigan, US.
Hire a consulting engineer who specializes in wastewater treatment. Most domestic plants are activated sludge, but circumstances ( size, location , availability of raw materials , effluent requirements, existing facilities, local costs etc) could dictate other choices. MOP 8 published by WEF discusses options. N & P are normally important only if effluent requirements include them.
Dear Lara: please contact to fgiralt@amuerinternacional.com who can give you a solution from Aquatreat of Barcelona, Spain. This Company has supplied plants for Portugal many times. And so to analize your request and size of the corresponding solution. The domestic effluent has a standard and range of composition.
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by Eduardo Riveros Miranda, Ingeniero Civil Químico con postgrado en Alimentos - Asesorías y Capacitación Técnica