One of the disadvantages of the system is the potential failure of mechanical components within the system, such as the shafts, disks and bearings. The system is commonly installed in a concrete tank, which can make it difficult for plant operators to monitor the system effectively within the tank.

What is the purpose of a rotating biological contactor?

A rotating biological contactor or RBC is a biological fixed-film treatment process used in the secondary treatment of wastewater following primary treatment. The primary treatment process involves removal of grit, sand and coarse suspended material through a screening process, followed by settling of suspended solids.

What is the main difference between trickling filters and rotating biological contactors RBC )?

The higher contact time in RBCs due to rotation allows up to 8 to 10 times higher levels of treatment than in trickling filters (WSP 2008). Also because the rotation allows both optimum wetting and oxygen supply, RBCs are generally more reliable than other fixed-film processes.

When using a rotating biological contactor which two conditions are required for effective operation?

When using a rotating biological contactor (RBC), which two conditions are required for effective operation? A. The rotating drum(s) must be 50 percent submerged and rotate at a speed greater than 2 rpms.

What are advantages of wastewater treatment by RBC?

Advantages Offered by Rotating Biological Contactors

• Short contact periods are required because of the large active surface.
• They are capable of handling a wide range of flows.
• Sloughed biomass generally has good settling characteristics and can easily be separated from waste stream.

Why is the sludge aerated?

Why is the sludge aerated? Explanation: An activated-sludge reactor is a system in which pre-treated sewage (i.e. having passed through primary treatment) is aerated to promote the growth of bacteria (cells) that gradually consume the organics in the sewage.

What does zero discharge actually refer to?

The principle of “zero discharge” is recycling of all industrial wastewater. This means that wastewater will be treated and used again in the process. Because of the water reuse wastewater will not be released on the sewer system or surface water.

Which of these is not an advantage of a trickling filter?

Which of these is not an advantage of a trickling filter? Explanation: The oxygen delivery is cheap and they consist of non-electric systems. Trickling filters owe a low construction cost. Trickling filters are temperature dependent which makes it a disadvantage of a trickling filter.

What is the use of trickling filter?

Trickling filters (TFs) are used to remove organic matter from wastewater. The TF is an aerobic treatment system that utilizes microorganisms attached to a medium to remove organic matter from wastewater.

Why secondary clarifier is needed for an RBC?

Recirculation of secondary clarifier effluent is necessary to maintain constant flow through the RBC to keep the biofilm submerged for a sufficient period of time. media in the RBC, incoming wastewater that contains a toxic substance can potentially wipe out the entire biological population when it enters the RBC.

What is meant by bulking of sludge?

Abstract. Sludge bulking is the most common solids settling problem in wastewater treatment plants, which is caused by the excessive growth of filamentous bacteria extending outside the flocs, resulting in decreasing the wastewater treatment efficiency and deteriorating the water quality in the effluent.

What is required to keep activated sludge suspended?

What is required to keep the activated sludge suspended? Explanation: To maintain the aerobic conditions and to keep the activated sludge suspended, a continuous and well-timed supply of oxygen is required. Flocs of bacteria, which are suspended and mixed with wastewater is used for the process.

What is the purpose of an underdrain in an RBC?

Underdrain System: The underdrain system in trickling filters serves two purposes: ( a ) To carry the wastewater passing through the filter and the sloughed solids from the filter to the final clarification process, and ( b ) To provide for ventilation of the filter to maintain aerobic conditions.

What is activated sludge treatment process?

The activated sludge process is a means of treating both municipal and industrial wastewater. The activated sludge process is a multi-chamber reactor unit that uses highly concentrated microorganisms to degrade organics and remove nutrients from wastewater, producing quality effluent.

How does a submerged aerated filter work?

Submerged aerated filtering A blower sends air to the bottom of the bed to provide oxygen for the biomass to support the oxidation process. The air stream promotes both efficient mixing of the effluent and disturbance of any excess solids from the filter medium.