) : unit nominal capacity: 2,500 t · year–1 of extended aeration dewatered sludge; minimum sludge dry solids content: 14 %; volume of sludge treated during peak periods: 250 m3 per month...

tend to vary from 1 to 3 chlorine-equivalent per litre. metal recovery In many industries, but mainly those involved in surface treatment, hydrometallurgy and electronics, electrolysis is used...

compatible with the natural environment. At that time, it was decided not to include a Densadeg given the fairly low throughput to be processed (100 m3·h–1). However, even in this case, it would be the best...

will take between 30 to 120 minutes. In order to ensure that the reaction is self-sufficient in terms of heat, the amount of COD injected into the reactor must be greater than 25 g·L–1 of COD, and the sludge...

. installation rules Silos (photo 4) must be fitted with a vent equipped with a bag filter and a pressure relief valve to deal with overpressure. The bends on 80 or 100 mm filler conduits (1) must have a bending...

be used to produce a suspension often called a "slurry" containing 30 to 50 g · L–1 of PAC. Table 2. Table showing the different types of installation In large plants (figure 23), the screw...

. In systems where the feed water is less than 1° TH, phosphates are used to regulate alkalinity or boiler water pH and, therefore, to avoid acid or alkaline corrosion of boiler internal walls. Phosphates...

: crystallisation inhibition In supersaturated solutions, if small amounts of inhibitor, approximately 1 mg · L–1 are added, this will extend seed germination time and slow down seed growth (figure 10...

As discussed previously (see industrial water), the agri-food industry is a substantial water consumer (e.g. from 1 to 5 L of effluent per litre of beer, milk, carbonated drink, wine type beverage...

as anodic inhibitors. When chromates were being used on their own, amounts of 400-600 mg · L–1 of chromate ions were needed to properly inhibit steel. The use of zinc (~ 5 mg · L–1 of Zn2+) with chromates...

for gas/liquid exchanges and characteristic constants of gases). By way of an example, subject to a gas pressure of 101.325 kPa (1 bar) at 10 °C, the solubility of the main gases is represented in table 5...

from 5 cm up to 30 cm. 30 cm to 1.5 m long, the system provides 0.3 m² to 41 m² membrane developed surface areas. Several elements (two to eight) are installed in series in the same cylindrical housing...

of elementary sulphur: The sulphur produced is stored in the bacteria cell or excreted depending on the species. Later on, it may be converted into sulphuric acid : Photo 2. Thiospirillum x 1...

inhabitant per year or yet again, 275 L.(inhab.d)-1. Table 9 illustrates the variable nature of water demand depending on different dwelling conditions. Table 9. The variable nature of water demand...

solids parameters (respectively 50, 250 and 85 mg·L–1). These rules on acceptable margins must be compared to the "percentile" concept routinely applied in the United Kingdom. For instance, a 95 %-ile...

, protected or plastic steel containers depending on the applicable codes. The product is dissolved in water to form a stock solution that has a concentration of approximately 3 g · L–1, injected in the water...

.3 mg . L-1 of zinc to inhibit biological iron removal). In particular, it should be noted that the limit value for certain compounds can be largely increased through suitable acclimatisation (as...

and their metabolites can impart an unpleasant taste and/or smell to the water, and removing these can prove very expensive. When retention time in the storage tank is longer (1 month), a zooplankton population may...

, this void is reduced to height " h1 ", equal to the product of “H” by the waterair mix density. The difference H – h1 = h2 represents the pressure drop thus created by the air input (figure 21). Figure...

% formal­dehyde solution per 100 mL of sample). When the water is low in algae, it requires concentration by centrifugation (5 000 rpm–1), by sedimentation (1 week in a 1 L test tube) or by filtration...