Size and capacity of oil & grease chamber

The presence of grease and oil pollutes the aquatic life and fresh water. To eliminate oil and grease is very essential but the common techniques are not enough. Enzyme are selected to assess the quality of water. And adsorption units representing developed new laboratories are also used to assess the quality of water.

The conventional techniques eliminate all the oil and grease by the usage of skimming tanks and oil and grease traps in treatment plants but the major disadvantage of these methods is their less efficiency of removal.

The residue oil causes clogging of pipes in treatment units which then need cleaning and sometimes replacement of pipes. All this causes increment in the maintenance and cost of inspection. Alternative uses of biochemical route have gained more attention due to their clean and friendly advantages and to overcome the limitation.

Microbial activity plays an important role in performance, strength purification process, and the removal of pretreatment process in wastewater treatment plant that depends on cost of enzyme. Environmental studies tell us how to prevent the blockage of fat prevention in waste systems prior to discharging wastewater into sewage system. These studies investigated new ways to degrade organic matter commercially which cleans holding tanks, septic tanks, grease traps etc.

Grease Interceptor is an instrument that is used to trap oil, grease, food solids etc. from the wastewater prior when they enter into a system known as a sewer system. The Oil and Grease or O&G Trap prevents the clogging of sewer by preventing the Oil, grease fats and solids from going through the sewer, here we are presenting a way out of designing these grease interceptors for easy removal of oil and grease which could otherwise pose threat to aquatic life and also is not good for pipelines and appliances.

Use the following formula from Appendix H of the Uniform Plumbing Code to determine the size of grease interceptor required by a Food Service Establishment:

No. of Meals per peak hour¹ * Waste Flow Rate² * Retention Time³ * Storage Factor⁴ = Interceptor Size (Liquid Capacity)

1) Meals Served at Peak Hour

2) To calculate the Waste Flow Rate, add all that apply:

With dishwashing machine 6 gallons

Without dishwashing machine 5 gallons

 Single-service kitchen 2 gallons

Food waste disposer 1 gallon

 3) Retention Times:

Commercial kitchen waste Dishwasher 2.5 hours

            Single-service kitchen single serving 1.5 hours

4) Storage Factors:

Fully equipped commercial kitchen:

8-hour operation 1

16-hour operation 2

24-hour operation 3

 Single-service kitchen 1.5

Grease, oils, and fats-laden wastewater from the food service industry comes from kitchen sinks and travels through pipes to the treatment plant. That is why it is necessary to clean the grease traps in restaurants on a regular basis. Grease traps and grease interceptors are beneficial to more than just restaurants. Grease traps are required at hospitals, malls, schools, and other establishments to avoid clogging sewer systems and being penalized as a result of any blockages. When a sewage blockage occurs, the establishment's internal plumbing systems must be repaired, resulting in unprofitable downtime for the duration.

If we talk about the oil and grease which has somehow entered the wastewater treatment plant, it can be removed by the help of skimming tank and for the design calculation of skimming tank followings things should be kept in mind:

Design of skimming tank_

Empirical formula:

Surface area (L*B) = 0.00622q/Vr

Where q= rate of flow of sewage in m3/day, and Vr = minimum rising velocity of grease material to be removed in m/minute (0.25 m/min)

Detention time = 2minute to 5 minutes

For more information, contact Netsol Water: +919650608473 or write us: enquiry@netsolwater.com