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I think it is for chemical dosage. It seems a bit too low for the thermocouple probe. Is it a cascade type deaerator? If not I would not recommend using it and dose the chemicals before (the alkalizing agent) and after (oxygen scavenger, volatile chemicals) the dearator for several reasons. For...

What exactly is the water used for ? If it is for a cooling water system, one must take care that the solubility limit for calciumsulfate is not exceeded. If high cycles of concentration are used this might be the case. This means that depending on the application and the use of other sulfate...

This one's more basic: Basic Principles and Calculations in Chemical Engineering by David Himmelblau http://www.amazon.com/exec/obidos/tg/detail/-/0133057984/qid=1130396755/sr=5-3/ref=cm_lm_asin/103-1972348-8223839?v=glance It includes a handy cd-rom Edwin Muller KW2 Burau Veritas www.kw2.nl

I always had (or still have actually) a weak spot for Rules of thumb for chemical engineers: http://www.amazon.com/exec/obidos/tg/detail/-/0750675675/qid=1130396446/sr=8-1/ref=sr_8_xs_ap_i1_xgl14/103-1972348-8223839?v=glance&s=books&n=507846 not completely a beginners book but very handy...

Marvalar, a 9 bar boiler makes it a lot easier. Much less strict guidelines are needed. For a steam generator at 9 bar there are other guidelines available. The following values are issued by the company I work for: pH minimum 7,0 but a bit higher would give better protection against corrosion...

Marvalar, this strongly depends of the pressure and type of the boiler you are using. Based on this you can choose a conditioning regime which sets the quality of the feed water. I expect that you are using a drum type boiler above 125 bar. For this type of boiler VGB (Germany) guidelines...

It is indeed possible to go to 10-15 cycles in case feed water is used which already has low concentrations of Mg and Ca. It is however the question what is the point of this. The amount of water which is saved is low and at a certain point the costs of chemicals will increase drastically. In...

Depending on the process ozone (can be operated in combination with UV) or low chlorine will do the job. It is however also important to look at the process circumstances which cause MIC. First of all there is the temperature. Unfortunately, this cannot be controlled since it's a process...

What is the origin of the condensate ? If it's medium or high pressure steam, it would be a good idea to check the organics content of the boiler water. It is a known fact that organics under these circumstances (high T and high p, superheated steam) decompose. Ultimately one will get CO2 and...

I already suspected that this might be the reason for the change in Hg-emission. Thanks for the info.

Thanks for the info so far. The installation under study is a coal-fired power plant in which an SCR will be placed. Practice has shown that a power plant fitted emits less Hg to the air (cause unknown by me). However, to keep the mass balance correct, our client assumes worst case that this...

Currently I am working on a project concerning the waste water treatment of a power plant. It has been installed to convert the waste water of the FGD (flue gas desulphurization). The power plant is going to install a deNOx which will result in the introduction of ammoniumsulfate and an increase...

Gajjar, If your problem is the environmental effect of the chlorine, it might be worthwhile to consider the discontinuous use of chlorine (pulse chlorination). This method can reduce your chlorine consumption with up to 90 %. Think I have a paper on it on my pc, please contact me if you're...

rmw, It is not necessary to abandon the ammonia dosage completely. One can for example add ammonia up to pH 9.2 (50-100 ppb NH3)for example combined with 50-100 ppb of oxygen (VGB calls this the combi fahrweise). It gives the best of both worlds. It is even applied in the presence of copper...

The idea is reasonable, organic foulants can be removed this way. I noticed however in practice another technique in which the ion exchange resin is treated with brine. It takes a longer contact time and of course adequate rinsing. Good luck Edwin Edwin Muller KEMA Power Generation &...

Uacar, First thing one has to ask oneself is : do I need an oxygen scavenger? Usually the de-aerator is good enough to get a low oxygen level. (However if I had to choose for an oxygen scavenger I would go for carbohydrazine because of safety reasons.) One can even choose a further extreme if...

Fred, forgot part of your question. Cation conductivity is the conductivity after passing a cationic ion exchanger. It is a more sensitive reading than conductivity (a hydronium ion has a larger specific conductivity than the other ions. If you like advise on treatment of your boiler feed water...

Fred, to get a proper idea about the conditioning regime, you first have to tell more about the type of boiler (pressure, temperature, what materials is the boiler including the condensor made of etc.). Then of course there is the question which quality of water you produce in your demin plant...

Spector, the problems you have are either caused by too high an oxygen content in your makeup water or trouble with the conditioning of your water/steam circuit. If the conductivity of your condensate is in microS/cm, than it may be worth too have a look at the composition of the water/steam...

Arahimanian, there is a risk of galvanic corrosion of the bronze. How large are the bronze and stainless steel surfaces which are exposed to the air/liquid ? Edwin Muller KEMA Power Generation & Sustainables Arnhem, The Netherlands E-mail e.f.muller@kema.nl Internet...