UASB Reactor is a commonly used equipment in Wastewater Treatment. It uses anaerobic reaction to decompose organic matter in sewage into gas, and then realizes solid, liquid and gas three-phase separation.
Upflow Anaerobic Sludge Blanket UASB Reactor for Wastewater Treatment Equipment
UASB Reactor is a commonly used equipment in Wastewater Treatment. It uses anaerobic reaction to decompose organic matter in sewage into gas, and then realizes solid, liquid and gas three-phase separation. The UASB reactor can not only process high-concentration organic wastewater such as alcohol, molasses, citric acid, and other production wastewater, but also process medium-concentration organic wastewater, such as beer, slaughter, and soft drink, and low-concentration organic wastewater, such as domestic sewage and urban sewage.
The principle of UASB reactor：
The wastewater is introduced into the bottom of the UASB reactor as evenly as possible, and the wastewater passes upwards through a sludge bed containing granular sludge or floc sludge. Anaerobic reactions occur during the contact of wastewater and sludge particles. Biogas produced in the anaerobic state (mainly methane and carbon dioxide) causes internal circulation, which is beneficial for the formation and maintenance of granular sludge. Some gases formed in the sludge layer adhere to the sludge particles, and the attached and unattached gases rise towards the top of the reactor. The sludge rising to the surface hits the bottom of the three-phase reactor gas emitter, causing degassing of sludge floes with air bubbles attached. After the bubbles are released, the sludge particles will settle on the surface of the sludge bed, and the attached and unattached gases are collected into the gas collection chamber of the three-phase separator on the top of the reactor.
structure of USAB reactor：
The baffle which is placed under the gap of the gas chamber unit is used as the gas emitter and prevents the gas bubble to enter the precipitation zone. Otherwise, the flocculation of the precipitation zone will be caused, which will hinder the precipitation of particles.
The liquid containing some residual solid and sludge particles enters the precipitation zone through a slit in the separator.
Since the area of overcurrent of the separator's inclined wall is increased near the surface of the water, the increase velocity is close to the emission point.
The sludge flocculation can be flocculated and precipitated in the precipitation area due to the velocity of the sludge.
Accumulated on the three-phase separator sludge flocs will more than to keep it to a certain extent in inclined wall friction, it will slide back into the reaction zone, this part of the sludge and will react with water organisms.
1. Residual biogas burner
It is generally not allowed to discharge the remaining methane into the air in case it pollutes the atmosphere.
When the residual methane gas is not available, a residual gas burner can be installed to burn it.
The burner shall be installed in a safe area and shall be installed with the valve and the flame arrester.
Residual gas burner is a safety device that can automatically ignite and fire extinguishing.
The distance between the residual gas burner and the digester cover, or the storage tank, usually requires at least 15m and should be set to open ground easily monitored.
2. Heat preservation and heating equipment
Anaerobic digestion is affected by temperature as much as other biological processes, and the anaerobic process is more influenced by temperature.
Medium temperature anaerobic digestion of the optimal temperature range from 30 to 35 ℃, 20 ℃ and 10 ℃ can be calculated the digestion rate of about 30 ℃, respectively, the maximum of 35% and 12%.
Therefore, the importance of heating and heat preservation is self-evident.
The heat exchanger is necessary if the factory or nearby has the available waste heat or needs to be effective from the discharge.
3. Monitoring equipment
In order to improve the operation reliability of the anaerobic reactor, you must set up various types of measuring equipment and instrument, measuring equipment such as control of water inflow, o-phenylenediamine and pH meter (pH), such as temperature measurement automation instrument.
Automatic measurement equipment and instruments are the basis of automatic control.
The purpose of the monitoring of UASB reactor is mainly two. One is to understand the situation of entering and leaving water so as to observe whether the water intake can meet the process design situation.
Another purpose is to control the operation of various processes and to determine whether the process is normal.
Due to the particularity of UASB reactor, some detection items such as volatile organic acid (VFA), alkalinity and methane are also added.
However, these devices are standard equipment and some devices are difficult to measure and control online.
The three-phase separator is the most characteristic and important device of UASB reactor.
It also has two functions:
1) can collect biogas generated from the reaction chamber under the separator;
2) precipitate the suspended material above the separator.
Summary of design points of three-phase separator:
1) the area of the opening section of the gas chamber shall be 15 ~ 20% of the total area of the reactor.
2) when the height of the reactor is 5 ~ 7m, the height of the gathering chamber is 1.5 ~ 2m;
3) the gas liquid interface should be kept in the gas chamber to release and collect gas to prevent the formation of scum or foam layer.
4) in the upper part of the gathering chamber, the foam nozzle should be set up to eliminate the foam when dealing with the serious foam problem of the sewage.
5) the cover between the reflector and the slit should be between 100 and 200mm to avoid the rising gas entering the settling chamber;
6) the direct pipe of the outlet pipe should be sufficient to ensure that the gas from the chamber is introduced, especially in the case of foam.
For low concentration wastewater treatment, when the hydraulic load is restrictive design parameter, the three-phase separator gaps remain big flow area, makes the biggest rise velocity on the water cross section as low as possible is very important.
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remarks：Main Equipments Packages Testing Devices Delivery:
500kg or more