Ecopreneur has developed many wastewater treatment plants for differently sized populations, which comprise a wide range of load and flow requirements. The processes used will vary depending on the plant’s size and customer’s requirements. Most activated sludge systems have been used in different modalities for organic matter (BOD5) and nutrient removal (N and P), obtaining a treated effluent.
Ecopreneur’s experience includes designing and installing conventional activated sludge plants, extended aeration, MBR, MBBR and anaerobic treatments, among other biological systems. Primary treatment systems, odor treatment, dewatering, conditioning, stabilization and sludge drying complete the process line of these plants.
The primary treatment’s goal is the removal of contaminants, such as coarse solids, fine solids, sand and grease, which are in wastewater.
Ecopreneur has a wide range of automatic equipment designed for each application regarding these contaminants.
Compact Pretreatment Plants.
Grit Chamber and Degreaser
Grit Washer and Classifier.
Solids Compactor Conveyor.
Secondary treatment consists of a series of biological processes that use microorganisms to eliminate biodegradable organic matter along with compounds containing nutrients, such as N and P, when necessary, according to specific requirements of the treated water quality.
Activated Sludge / MBR (Membrane Bioreactor) / MBBR (Moving Bed Biofilm Reactor)
Traveling and circular bridge clarifiers.
As part of the secondary treatment, the best method for biomass separation (activated sludge) from the treated water can be defined. Gravitational clarifiers with circular or traveling bridges are usually used for this purpose.
DAF technology is also used for secondary solid-liquid separation.
Dissolved Air Flotation (DAF)
One of the main targets to consider is the elimination of fecal coliforms to values below 1,000 NMP/100ml. During the secondary treatment process, the amount of FC is reduced considerably; however, it is not reduced by enough to comply with the regulatory requirements, which require the incorporation of a disinfection stage for the effluent. Ecopreneur provides several systems for disinfection, such as:
Depending on the customer’s requirements, sludge produced by Biological treatment plants is thickened and subsequently dewatered using a mechanical system. The main goal of this operation is to reduce the humidity and volume of sludge to be disposed.
Before sludge dewatering, it is advisable to increase solids concentration, which is achieved using sludge-thickening systems which can be either gravitational or mechanical. After thickening, sludge is dewatered by equipment such as a filter press, filter band or centrifuge.
Table and Drum Thickeners.
Dissolved Air Flotation (DAF)
There is the option of drying sludge by taking advantage of solar energy using a proprietary system, Thermo-system® (Germany), to reach sludge quality type A or B according to SD 04/2009 without adding lime or higher levels of dryness than those conventionally reached with exclusive dewatering. Thermo-system® uses solar radiation energy, controlling drying mechanisms and managing atmospheric variables to evaporate water from sludge to produce up to 90% dried solids.
In the absence of air wastewater treatment processes, and others involving degradation, transformation or accumulation of wastewater or organic matter, can generate odorous gases composed mainly of volatile organic compounds (VOC), hydrogen sulfide and ammonia.
Odor treatment designs are based on 3 stages:
1) Confinement of odors generation spaces (encapsulation).
2) Conduction of air to the treatment system
3) Odor treatment to remove the mentioned odoriferous compounds.
The treatment usually takes place in a biofilter, which consists of an organic or inorganic filter bed to support microorganisms that will remove the polluting gaseous compounds. The gas to be treated flows through the filter bed, then the compounds are transported from gas to a liquid phase, where they are degraded by the active biomass which adheres to the organic support surface.
Conditions which must be monitored in the system include pH, water content, nutrient concentration and the gas-liquid phase contact surface area. When these conditions are maintained and balanced, the system will work correctly and effectively remove the contaminating gases.
The main applications of odor treatment are:
• Collectors and lifting plants for sewage and wastewater in general
• Accumulation tanks (equalizers, sludge tanks)
• Head works and dewatering rooms
• Facilities where solid and liquid wastes of organic origin are handled (food processing plants and agricultural products in general)
Depending on use requirements and/or disposal of effluents from wastewater plants, in some cases it is necessary to complement the secondary treatment with an additional treatment system to improve the quality of the effluent. In this case, normally, the tertiary treatment system’s goal is to decrease the content of total suspended solids. In this context, some solutions are sand filters or ultrafiltration systems.