Sewage treatment works

Effluents of oil refineries, textile mills, power stations, pulp mills, sewage treatment works, vegetable oil factories... 

As the most significant point sources of phosphorus are those from sewage treatment works (STW), control of phosphorus loading is most readily achieved either by precipitation of phosphorus with iron salts (iron(lll) sulfate or iron(lll) chloride) or by biological removal. The latter can only effectively be achieved in STWs using activated sludge and there have been many descriptions of this technique. ... 

A problem of many sewage treatment works in the UK is that urban drainage is included with domestic sewage in the sewage collection systems. The resulting storm-water discharges, at times of heavy rainfall, lead to continuing phosphorus export to the river. Correction of this problem requires considerable investment in separate systems. 

Harries, J.E., Janbakhsh, A., and Jobling, S. et al. (1999). Estrogenic potency of effluent from two sewage treatment works in the United Kingdom. Environmental Toxicology and Chemistry 18, 932-937. 

Johnson, L, Hetheridge, M., and Tyler, C.R. (2004). Assessment of the (Anti-) Oestrogenic and (Anti-) Androgenic Activity of Sewage Treatment Works Effluent. R D Technical Report, Environment Agency. 

Sheahan, D.A., Brighty, G.C., Daniel, M., and Kirby, S.J. et al. (2002). Estrogenic activity measured in a sewage treatment works treating industrial inputs containing high concentrations of alkylphenohc compounds—a case study. Environmental Toxicology and Chemistry 21, 507-514. 

Johnson AC, Williams RJ (2004) A model to estimate influent and effluent concentrations of estradiol, estrone, and ethinylestradiol at sewage treatment works. Environ Sci Technol 38 3649-3658... 

Johnson, I. and M.B. Jones. 1989. Effects of zinc/salinity combinations on zinc regulation in Gammarus duebeni from the estuary and the sewage treatment works at Looe, Cornwall. Jour. Mar. Biol. Assoc. U.K. 69 249-260. 

Gostelow, P. and S.A. Parsons (2000), Sewage treatment works odour measurement, Water Sci. Tech., 41(6), 33-40. 

Clean Water Act (CWA) was first enacted in 1948 as the Federal Water Pollution Control Act. Subsequent extensive amendments defined the statute to be known as the CWA in 1972 it was further amended in 1977 and 1987. The CWA provides EPA authority to regulate effluents from sewage treatment works, chemical plants, and other industry sources into U.S. waterways. EPA has recently undertaken control efforts in on-point source pollution as well. 

In the assessment of odour production and nuisance from industrial processes the techniques are by now reasonably well established, and their accuracy and consistency are in principle known. There are major differences however between say a rendering plant on the one hand and a sewage treatment works on the other. One difference is psychological to many people an odour problem is necessarily concomitant to the existence of a sewage works. There have been instances of a well-operated sewage works built next to a tannery, where the sewage works has been almost universally blamed by irate local residents for a problem to which it has contributed in only a minor way. To this extent, for some people the only way to convince them that there is no odour nuisance would be to shut the works completely, and even then it is known that complaints can continue for some time afterwards. 

Principle Sources of Odour at Sewage Treatment Works... 

Odour measurements were made on routine ex-works sludges collected from sludge holding tanks at three sewage treatment works. Odour potential was measured using the standard method (see 3.1). Investigations carried out were comparisons of -... 

With a simple piece of apparatus to extract odour samples from slurry and sludge samples, which is not specific to any particular design of olfactometer the method is suggested as a standard for the day-to-day assessment of slurries, and the determination of operating procedures, particularly at sewage treatment works. 

It is clear then, that the concept of Odom Potential of a sludge or slurry can be a useful tool not only to the odour specialist but also to the operators of sewage treatment works and agricultural slurry handling facilities in minimising the nuisance from the disposal of sludges. 

The major benefit from odour control is that it releases land otherwise barred to slurry spreading through its proximity to housing. This is equally important to both the farmer and water authority. For the farmer it removes pressure from other areas of the farm and allows more efficient utilisation of the nutrients in the slurry, and for the water authority, it can result in substantial savings in transport costs as farm land within urban areas is generally nearer to the sewage treatment works. 

Laxen, D.RH. and Harrison, R.M. (1981) The physico-chemical speciation ofCd, Pb, Cu, Fe and Mn in the final effluent of a sewage treatment works and its impact on speciation in the receiving river. Water Res., 15, 1053-1056. 

Purdom, C.E., P.A. Hardiman, V.V.J. Bye, et al. 1994. Estrogenic effects of effluents from sewage treatment works. Chem. Ecology 8 275-285. 

However, it is also common to use standards to set up the infrastructure, policies, controls, or rules that mean that incidents and risks occur with acceptably rare probabilities. These standards might be described as strategic standards. For example, controls on ammonia in sewage treatment works (which are back-calculated from environmental standards) are designed to promote good fisheries in the receiving river. The intention is to reduce serious incidents to an acceptable frequency in each river because the infrastructure of sewage treatment appears to function at this level of acceptable risk. This may result in a compromise, which is essentially that standards are set up as particular types of summary statistics and not as absolute limits. 

UK, Ashton and co-workers investigated the environmental transport of 12 human pharmaceuticals to streams and found that while 10 were detected in sewage treatment works effluent samples (e.g. ibuprofen in 84% of samples, median concentration 3086 ng L ), there were fewer and at lower concentrations in streams (e.g. ibuprofen in 69% of samples, median concentration 826 ng L ). 

Figure 3. Evolution profile of H-3 in various sample types. Sewage refers to sewage sludge pellets from the Cardiff East sewage treatment works.

UKWIR (2000) UK Direct Toxicity Assessment (DTA) Demonstration Programme Review of Toxicity Reduction Evaluations at Sewage Treatment Works. Report 00/TX/02/05... 

A petrochemical effluent of moderate toxicity being discharged to a sewage treatment works. 

Lye, C.M., C.L.J. Frid, M.E. Gill and D. McCormick. Abnormalities in the reproductive health of flounder Platichthys flesus exposed to effluent from a sewage treatment works. Mar. Pollut. Bull. 34 34-41, 1997. 

Stuetz, R.M., Fenner, R.M., and Engin, G. (1999). Assessment of odours from sewage treatment works by an electronic nose, H2S analysis and olfactometry. Water Res., 33, 453-61. 

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