Wastewater Optimization

When designing the treatment plant, the choice of optimal wastewater treatment technologies is a major focus.

The choice of technology depends on the composition of influent, the expected flow, and the effluent requirements.

The method of treatment is chosen according to these data (or in some cases, a combination of methods) and a technological scheme of automation is developed.

Experts at Bioxoca use knowledge of leading methods of wastewater treatment to analyze, calculate, and assess the technical and economic feasibility of the wastewater treatment scheme and select the optimal treatment technology.

Bioks wastewater treatment plans by Bioxica use rough mechanical, biological, physic-chemical treatments as well as post treatment by means of filters and ultra violet radiation and electrostatic field.

Rough mechanical treatment (depending on the size, composition of the wastewater and requirements of the client) in waste water treatment plants Bioks uses trash baskets, mechanical gratings, drum percolators, sand traps.

Trash baskets are used in small volume plants.

Trash baskets are set in sewage pumping stations (SPS), and are designed to collect large scum, which along with the waste water can get into the receptacle through the inlet pipe and damage the submersible pumps.

Grit Washer

Шнек со щеткой – screw with brush

Фильтрующий элемент - filter element

Отражающие экраны - reflective screens

Привод шнека  -screw drive

Зона выгрузки - discharge area

Зона промывки и отжима - washing and pressing area

Транспортирующая зона - conveying area

Зона фильтрации - filtration area

Grit washing is set up in the SPS and is a vital first stage in wastewater pre-treatment and eliminates the effluent of the scum while washing, pressing and transporting it to a designated container.

The grating is made of stainless steel, and is mounted in the canal inclined screw perforated screen or welded slit canvas. To clean the filter cloth from leftover waste, a screw is provided. It is an axial helix with variable pitch, equipped with a brush along the edge. Above the filter, the diameter of the helix decreases, and becomes an axial screw.

In this zone, the auger is cased in a closed housing lined with resistant polymer liner that is removable in order to protect it against abrasion. Inclined housing rests on the stand. At the top of the housing, nozzles are provided for washing of waste taken from grating and discharge area. The screw is driven by reduction geared motor mounted in the upper part of the grating.

Scum, retained on the filter cloth screw grating, is removed from it and moved upwards the body of the screw by a rotating helix, wherein the filter cloth is thoroughly cleaned with brushes arranged around the edge of the screw.

Dewatering of the waste happens due to reduction of screw steps. In the upper part of the housing, the scrum is washed from organic impurities with water from the nozzles. Pressed water and wastewater from washing is directed into the channel before the grating through conduit. In the discharge area washed and pressed to 35% of the original volume scrum is thrown into the waste container through the special opening.

Drum percolator Bioworks (Germany) with a screw conveyor percolators and press waste

Such equipment is used without primary setting tanks, thus providing detention of scum, sand, and the larger suspended solids. Fine filters are used instead of gratings here, which are designed as a rotating drum with a press and waste disposal system.

There are 4 drum gratings (3 operating and 1 spare), a conveyor and a press for pressing the waste.

Diameter and length of the drum are designed in accordance with peak inflow. Drum drive is designed as a geared motor and is automatically operated with a built-in water level gauge. The drum is also equipped with an automatic cleaning device.

The bottom of the device features an output for discharge of treated effluents into the open channel.

The entire device is manufacture of stainless steel, which significantly extends its operating time. It is equipped with a built-in system for emergency overflow with an alarm.

Filtered material is separated from the drum with a scraper and diverted to the screw press or directly into the container.

Tangential sand trap

Tangential sand traps are the most commonly cylindrical. Wastewater flows into them tangentially, causing a rotational movement which promotes separation of large mineral deposits and pulls them to the bottom of the device. Periodically an airlift removes the accumulated mineral deposits.

Biological Treatment

The main advantage of biological treatment is its absolute environmental safety. In addition to lower operating costs it provides an improved flexibility in handling changes in pollutant characteristics.. The essence of this method is biochemical degradation by microorganisms which consume various organic and some inorganic compounds.

Aeration tank

The aeration tank is a reservoir, where decomposition of organic substances though the use of microorganisms occurs. To create the ideal conditions for aerobes, air is supplied by a compressor or other means to the aeration tank, thus ensuring effluent aeration.

Physico-Chemical Wastewater Treatment

To ensure a high level of wastewater treatment, it isn’t always enough to perform only biological treatment, especially for industrial effluent. In cases like this a physico-chemical treatment method is included. It is based on the usage of reagents such as coagulants and flocculants.

Coagulation (from Latin coagulare - "to gather together").

Very small colloidal particles of impurities presented in water combine into large masses (flakes) under the action of the coagulant and then are removed. During biological wastewater treatment, phosphorus concentration in the wastewater is not optimally reduced and exceeds the value of the maximum permissible concentration (MPC) of phosphorus to be released into surface waters by 2-5 times. Using a reagent in allows to reduce concentration of phosphorus by 85%, soluble phosphate by 95% and leads to compliance with MPC standards.

Flocculation (from lat. flocculi — shreds, flakes) — a kind of coagulation, in which small particles that are suspended in water - form a loose flocculent accumulation, i.e. flocculi. When using flocculants, overgrown sludge has lower water content after dewatering allowing for the filter press to have a higher carrying capacity.

Reagent cleaning is quite effective and easy. Industrial wastewater treatment with reagents includes several steps:

1/ Preparation and dosing of reagents

2/ Mixing reagents with water;

3/ Flocculation;

4/ Separation of flocculent impurities from the water.

Preparation and dispensing of reagents station

Preparation and dispensing of reagents station includes:

• tank for chemicals, where  the reagent is prepared;
• mixer for mixing the reagent;
• metering pump for supplying metered portions of reagent in wastewater treatment plants.

Electrostatics and ultraviolet wastewater treatment

Non-pressure UV installation with submersible UV modules.

UV disinfection is a physical process, based on the natural action of sunlight. Microorganisms such as bacteria, viruses, yeast, etc. become immediately inactivate under the action of UV rays. This method of water disinfection is the best alternative to chlorine disinfection since the use of chlorine, chlorine dioxide, and other chemicals, can lead to harmful consequences for both health and the environment. UV light source is a mercury-argon or mercury quartz lamp placed in a quartz tube in the center of the metal casing, which emits rays freely. Disinfection occurs during the flow of water in the space between the housing and the tube when the microbes are exposed to UV rays. Ultraviolet radiation works immediately, so there is no need for contact basins. Bactericidal installation is compact and can be easily automated.

Installation of wastewater treatment trough electrostatic E-1-1.

Under the influence of the electrostatic field in the aquatic environment the structure of water changes, which increases the rate of physical and chemical processes. This increases the efficiency of wastewater treatment and its partial disinfection.

Tertiary bioreactor and carbon filter treatment

Bioreactor

The bioreactor is a tank loaded with gravel grit 2-10 mm, and a plastic crate. Gravel grit delays suspended solids remaining after rough mechanical and biological treatment. The plastic crate is a filled with medium for growing biofilms of microorganisms, it is a kind of biological filter. Upon contact with effluent, adsorption and oxidation of organic substances occurs.

Carbon filter

Carbon filters are used to remove impurities such as chlorine, turbidity, and organic sulfide compounds. The principle of carbon filters is based on adsorption. Carbon filters are very simple to use and require no reagents. Activated carbon, adsorption properties of which have long been known, is used as backfill in carbon filters. Water, passing through such a filter, becomes transparent and has no odor.

In the design of water treatment facilities, it is necessary to perform several tasks: the choice of model structure; rational arrangement; minimization of environmental pollution.

For each client, we select the best functional solution, focusing on space-efficient solutions, exploring the area characteristics as well as specifications provided by the client.

When determining best use of area, our experts at Bioxoca provide an individualized approach to every project.

Before we start designing wastewater treatment plants, the technical conditions provided by the client are considered in order to select optimal technology and the most effective equipment.

Reasonable selection of equipment, good location, and compliance with regulatory requirements are crucial to proper treatment facility operation.

The experts of Bioxoca choose the best options for efficiency, reliability, and cost-effectiveness.