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Poultry Processing Waste Water Treatment

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artetter

Structural
Oct 20, 2008
13
US
Hello- I'm an engineer working on a fairly small waste water treatment design project for a poultry processing facility on a small familly farm. They plan on using a maximum of 500 gallons of water per day for washing the facility down after several hundred birds have been processed.

Do you have any recommendation on where I could find design guidance or system recommendations for such a small system and facility? Any information on operating success with similar systems would be great as well.

Thanks.
 
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artetter

A couple of questions that you need to consider before any advice could be given

1) What do you want to do with the treated wastewater eg: recycle , reuse , irrigate , dispose to sewer , release to the environment etc

This will determine what standard of treatment may be required. Where you live may have rules about what you are trying to do.

2) You say the water comes from washing the facility down. But this is not an indicator of quality of the wastewater. Therefore you will need to have some tests done to determine how it might be possible to treat the wastewater. For example does it contain lots of solids, are detergents or cleaners used in the washing process, is the water hot or cold , what is the COD (chemical oxygen demand) , BOD (biochemical oxygen demand) , pH , total nitrogen , total phosphorus, etc.

3) How complex can this process be in terms of skills , manpower and money available. For example if you wanted to spend a lot of money you could produce top quality drinking water. But maybe you don't want to or need to produce top quality drinking water so something a lot cheaper and less complex maybe okay.

Regards
Ashtree
"Any water can be made potable if you filter it through enough money"
 
ashtree-

The treated water will be discharged into an absorption field. Because the maximum daily flows will be less than 500 gallons/day, the county seems to be OK with it.

At this time I'm assuming the concentrations for the facility will be inline with averages from other poultry processing facilities, BOD = 8.0, COD = 46, fecal = 537, ammonia = 1.44, oil and grease = 5.0, and TSS = 17 (all units in mg/l). I'm sure cleaners will be used in the wash down, disinfection process, but couldn't say which ones.

Initially, the thought was to run the effluent through a prescreen to capture solids, from the prescreen into one or two standard septic tanks with an effluent filter at the final outlet, then into the absorption field. This may do a decent job of capturing the oil and grease but I don't think it will reduce of the concentrations of much else, especially if heavy cleaners are used. I started leaning towards a constructed wetland installed after the tanks and before the absorption field. With the use of the wetland, I would expect to be able to reduce the size of the absorption field, but need some help in locating the proper design guidance to properly size the number of tanks, square footage of wetland and absorption field.

Thanks again.

 
Here is a link to a general description of poultry processing.

While you have not provided much information, the "less than 500 gallons/day" wastewater volume sounds suspect.

I know of firms using lagoon treatment, but not aware of anyone using a wetlands. Use of wetland would involve a discussion of the climate that you are working with.

Without a serious attempt at FOG removal, the absorption field will be DOA.

The concentrations of contaminants are somewhat suspect as well. One would think the concentration of contaminants would be stronger than human waste.
 
Bimr-

The link didn't seem to be available?

I forgot to mention that a grease trap will be required immediately after the prescreen. Are there other low cost / smaller scale FOG removal systems available? This is a fairly small operation, looking to primarily be a mobile processor.

You are correct on the waste numbers, they will look more like, BOD = 1900, fecal = 1.2x10^6, and TSS = 3248.
 
artetter

Those numbers certainly look more realistic but i too would share the concern about 500 gals/day as poultry processing is water intensive.

I see a couple of issues.

1) If strong cleaners/disinfectants are used then the septic tanks will be rolled for sure. This is a problem even at a domestic level with septic tanks and strong toilet cleaners.
2) Wetlands have their place but a wetlands for 500 gallons per day will be pretty small but as bimr suggests the suitability would depend on your climate. A warm sunny climate might work but a climate that had a part of the year snowed in is not going to. After all a lot of the nutrients in the water entering the wetlands is converted to cell matter, either plant or animal. If its very cold this process will be slow or non existent and therefore no treatment.

Assuming the county wont take it as is or with only a minimum of treatment i would suggest the following(i have given you some sizes just so you have an idea of what you might need but these are going to be very rough, because so much of the design will be very site specific)

1) Screening:Get rid of the coarse solids
2) Flow equalization/flotation/grease trap: Even up the flow, trap fat etc on the surface which will have to be skimmed regularly.
3) Anaerobic tank: Let solids settle and digest(the sizing of this will depend on the temperature of the water, and the quantity of solids). You would probably need at least one day hydraulic detention time and between 10 and 30 days solid retention times.
4) Aerobic/faculative lagoon ( this will depend on temperature, the amount of sunlight available and how much solids and BOD are removed in the preceding stages). 20-50 days hydraulic detention time with a prefferred depth of around 1.2 metres/4 foot.
5) Sewer or absorption field (absorption fields size largely depends on soil types, and climatic conditions). Too site specific to even off a range

I would still be concerned about the impact of the cleaners. Depending on what is being used you may also have to have some sort of pH adjustment process.

I hope this helps but i would suggest that you need to start by really confirming the quantity of waste to be treated.

Regards
Ashtree
"Any water can be made potable if you filter it through enough money"
 
At the risk of piling on, removal of the FOG before release to any field will be essential. Bimr made that adequately clear a couple posts ago.

Perhaps I'm reading this differently, but I understand that the 500G of CIP waste will be in addition to normal processing water. Is that correct? If so, the volume of processing water is also to be considered. As previously mentioned, the killing floor produces a fairly high BOD load.

If the total volume is as relatively low, you may want to SERIOUSLY consider ashtree's suggestion using an anaerobic process ahead of aerobic treatment, then discharge to surface or irrigation. Maintaining temperature for the anaerobic process is usually easy in such a plant since the CIP water will likely be very hot. The input energy for anaerobic is also very low, requiring only effective mixing. Doing this in a portable system may be a challenge however.

If the volume is actually as low as 500GPD, a membrane system can be very effective but will require intensive maintenance with the potential for FOG and surfactant contamination, but can also be made very portable. I have done this with a 40' container on a trailer for up to 2000GPD on high strength waste and 15000GPD in food waste in very small package plants.

MBRTrailer.jpg
 
ashtree, watthour and bimr-

Thanks for the responses, your input has been very helpful.

Regarding DAF units, where could I find information on smaller scale systems. Do you have any recommendations on manufacturers? Are there any effective alternatives to DAF?

Regards.
 
There are a number of firms that supply small units. Try Tenco Hydro.
 
I agree. Dissolved air flotation (DAF) water clarification process can be used for the separation of solids, grease, and oils. The advantages of DAF systems are in wastewater sludge thickening and in the ability to treat a wide range of suspended solids (fats, oil, and grease) in water at a high rate of removal. DAF works by producing a stream of microfine bubbles that attach to solids and lift them to the surface, where they can be removed by a surface scraping mechanism.

Chris Eberly, PE
 
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