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Waste Water -Microbiological Constitient?

Waste Water -Microbiological Constitient?

Waste Water -Microbiological Constitient?

(OP)
I have a waste water analysis from a wheat plant that, besides all of the usual dissolved solids constituents, contains a line item for "Microbial ATP" in units of "RAL". the values range from 4800-5100 RALs.

What is this, what do these values represent, and are these values considered high?

RE: Waste Water -Microbiological Constitient?

ATP is an organic phosphate. The analysis of phosphate depends on the pretreatment of the sample.The simplest analysis is reaction of the sample with molybdate to form a phosphomolybdate that can be determined colorimetrically.As for the RAL's ( recordable allowable limits ) 4800-5100ppm does seem to be a little on the high side. You may have to check your permit to find out what the limits actually are. I hope this helps.

Chymer

RE: Waste Water -Microbiological Constitient?

The RAL of 5800-5100ppm seems high, but may pertain to how/where the wastewater is released/dumped or the required treatment to allow release. Phosphate is now the number one limiting factor for application of manure-based wastewater to the ground - and the EPA has just instituted 1-year crop utilization of phosphorus by crop for determing application rate of wastewater. Seems your going to need to reduce the level of phosphate - but that depends on the phopshate level post-treatment. In-flow levels of that magnitude of phosphate is going to saturate the subsoil of any wastewater lagoon quickly. There are ways to reduce the phosphate load - especially as the "non-potable" water release limits are going to change for municipal wastewater.

RE: Waste Water -Microbiological Constitient?

ATP is a bio-chemical (adenosine triphosphate) found in all living cells. Testing for ATP in water samples has become a popular means to supply information as to the relative microbial count, activity or cleanliness of the water sample. The amount of ATP is proportional to the number of living cells but is not always proportional to traditional CFU/ml measurements used for quantifing microbial populations. (larger cells show higher ATP values and this affects the final microbial count.)

When a cell dies, ATP production is stopped and the ATP which has been made is rapidly degraded. A measure of ATP is proportional to the number of living cells, including large and small cells. When there is no ATP detected, it is generally accepted that there are no more living cells.
 
Instuments that test for ATP are special luminometers that measure bioluminescence and express test results in relative light units (RLUs), so I am not sure as to your units being RALs unless they are being stated as some sort of relative absorption light (units) -- I'll do some checking on this.

RE: Waste Water -Microbiological Constitient?

To follow my previous reply, it appears the "RAL" you refer to is "recordable allowable limits" and 4800-5100 is the recordable allowable limits for "Microbial ATP" which is measured (see my previous post) in RLUs (relative light units) for ATP measurement. Thus, higher (RLU) numbers would reflect more ATP and more microbial activity or numbers of microbes in the sample.

Unless you want (need) a certain amount of ATP (microbes) in the sample source, and 4800-5100 is that range, I would think that any readings less than the 4800-5100 RAL would be fine as that would indicate lower amounts of ATP.

RE: Waste Water -Microbiological Constitient?

(OP)
So, is there a quantitative relationship between RLU values and, say, the number of living cells per ml of sample?

Or is the RLU unit similar to the concept or the NTU/JTU for the measurement of turbidity?

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