BOD5 aeration device, five-day biochemical culture, bod5 water sample pretreatment

Description :

BOD5 aeration device, five-day biochemical culture, bod5 water sample pretreatment

　　RCHB123: I3345OI4433 and V Wang will share with you today's equipment content.

　　Address: Room 1305, Unit 2, Building 5, Zhengyang Tianjie, No. 28 Zhengyang Middle Road, Chengyang Street, Chengyang District, Qingdao City, Shandong Province

　　Brief introduction:

　　Five day biochemical oxygen demand (BOD5) is an important indicator for evaluating water quality in industries such as environmental protection, fisheries, tourism, and agriculture.

　　The government has issued a standard method for determining BOD5, namely the "dilution and inoculation method", and the National Environmental Protection Agency has provided a detailed introduction to the "dilution and inoculation method" in a special article.

　　The basic process of dilution and inoculation method is:

　　Prepare dilution water - Dilute the water sample to be tested - Cultivate at 20 ℃ for 5 days - Measure the dissolved oxygen content of the diluted water sample before and after cultivation.

　　As dilution water runs through the entire process, producing high-quality dilution water is one of the important tasks of this method. High quality dilution water requires dissolved oxygen to be close to saturation. Therefore, if necessary, purified air can be introduced through vacuum pump or water suction, or pure oxygen can be introduced through oxygen cylinders. Compressed air cylinders or compressors that do not come into contact with any lubricating oil can also be used to aerate the dilution water.

　　It can be seen that in order to ensure that the dissolved oxygen in the dilution water is close to saturation, aeration of the dilution water is the only way.

　　The BOD aeration device is mainly used to inject water samples or pre treated water samples into culture bottles, while adding carbon dioxide absorbent (NaOH). Then, the culture bottles are sealed and placed in a constant temperature box at 20 ± 1 ℃, and the samples in the culture bottles are cultured at a certain stirring speed. Due to the reaction of aerobic microorganisms, oxygen in the water is consumed and carbon dioxide is exhaled. If we absorb the generated carbon dioxide with NaOH in a timely manner, the oxygen in the upper space of the culture bottle will continuously supply the oxygen demand of the microorganisms in the sample, resulting in a decrease in gas oxygen partial pressure. By measuring the decrease in oxygen partial pressure with a differential pressure gauge, the BOD value of the water sample can be determined.

　　Usage: If it is an already assembled joint, rotate it by hand until it feels tight. Do not disassemble before use, otherwise dirt and debris particles may enter the interior of the joint; If it is not assembled properly, clean the impurities inside the joint, sleeve, and locking thread before assembling the BOD5 aeration special device to prevent poor sealing after assembly. If the joint was not assembled properly, clean the impurities first, screw it by hand until it feels tight, fix the high-pressure regulator on the bracket or vehicle, install the exhaust hose on the expansion type exhaust joint, and rotate the expansion joint locking nut by hand until it stops moving.

　　When the BOD5 aeration special device rotates, the mixed liquid on the surface is continuously thrown from the periphery to the periphery, forming a water jump, and the liquid surface is strongly stirred and sucked into the air. The BOD5 aeration special device has a lifting effect, allowing the mixed liquid to continuously circulate up and down, constantly updating the gas-liquid contact interface, strengthening the gas-liquid contact, and forming a negative pressure zone at a certain position. Inhaling air also prevents suspended solids in the tank from sinking, enhances the contact between organic matter and microorganisms in the tank with dissolved oxygen, and ensures that microorganisms in the tank have sufficient dissolved oxygen to oxidize and decompose organic matter in sewage.

　　The quality of the BOD5 aeration dedicated device not only affects the effectiveness of sewage biochemical treatment, but also directly affects the land occupation, investment, and operating costs of the treatment plant

　　Function Description:

　　This instrument is suitable for assisting in the determination of BOD values in water sources. It has advanced air compression and shock absorption systems, multi-stage noise reduction design, and extremely low noise. Using special synthetic rubber components, the air volume and pressure remain constant. Environmentally friendly design, oil-free lubrication, compressed air is quite pure. Reasonable and compact structure, achieving excellent results with low power consumption, economical and energy-saving, and long lifespan.

　　Instrument connection:

　　Connect the instrument according to the required length as shown in the following figure.

　　instrument composition

　　Host, siphon, check valve, filter separator.

　　Host: Control the air volume.

　　Siphon: Transmission.

　　Check valve: prevents backflow of water sample.

　　Filter air separation stone: filter dispersed air.

　　Working principle and characteristics:

　　Oil free: No need to refuel during work, keep the air fresh and clean

　　Electricity: Using electromagnetic vibration method, consumes less electricity

　　Low noise: manufactured according to the principle of air flow, using dual sound insulation

　　Stable performance: The air volume and pressure are very stable, suitable for places with stable water flow

　　Beautiful and elegant, with exquisite personalized design, made of materials that are durable and long-lasting

　　Operation instructions (aeration precautions)

　　Fill a glass bottle with a certain amount of distilled water (with copper content less than 0.01mg/L), and use an instrument to introduce air for 8 hours at 20 ℃ for aeration. Let it stand for 5-7 days to stabilize the dissolved oxygen. The mass concentration of dissolved oxygen should be 8-9mg/L.

　　Notes:

　　1. Do not immerse the air pump in water and do not apply oil to the air pump. When the air pump is used, it must be above the horizontal plane. If it is below the horizontal plane, a check valve must be installed in the middle of the air pipe to prevent water from flowing back into the pump through the air pipe and damaging the air pump.

　　2. If the instrument enters water, the power supply should be immediately cut off to avoid electric shock, and the air pump cannot be used again.

　　3. Regular cleaning and replacement of air pipes or gas stones can achieve high air flow and extend product lifespan

　　4. For your safety, if you find any damage to the power cord, please do not use it

　　5. Before placing your hands in water, please cut off the air pump and all electrical power sources first

AfterSalesService :

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