on the temperature and the pressure. Pure water under normal pressure experiences a maximum at approximately 4°C (exactly 3.982°C) and its variation as a function of the temperature is as follows (table1...

by conduction over a length x across an area S perpendicu­lar to this flow is given by the Fourier law : θ1 – θ2 representing the drop in temperature over the distance x, λ being the heat conduction...

Comprising clarification and filtration, this is the most widespread solution used for producing drinking water from surface water or from groundwater (≤ 500 mg · L–1 suspended solids, capable...

resistivity of the main conducting metals and alloys Resistivity at °C rt = r°(1 + at), ro = resistivity at 0 °C, a = temperature coefficient. t = temperature in degrees Celsius. lead battery...

references Marseille (France) 1,800,000 PE Csepel (Hungary) 1,600,000 PE ...

the difference, the amount to be injected. Under cold conditions, this amount will vary from 3.2 to 1.8 mg of MgO per mg of absobed SiO2 for an initial concentration of 20 to 40 mg.L-1. E.g : 150 mg · L–1...

The energy utilisation potential is defined by the raw sludge’s net calorific value (NCV). This potential is calculated from the NCV of the organic matter (between 20,900 and 23,000 kJ · kg–1...

of filter usually has the following properties : sand having a granulometry (E.S.): 0.55 to 1.35 mm; air flow rate: 55 m3·h–1·m–2; water flow rate during the air scour: 5 to 7 m3·h–1·m–2...

-molecular weight M of a gas expressed in g·mol–1 to its specific gravity d in relation to air under normal pressure and temperature conditions. specific heat By definition, the specific heat is the quotient...

, the following constitutes an example of a Naratherm dryer heat balance (table 6) : Table 6. NARA heat balance per kg · h–1 of water evaporated (based on a 20 % dry solids content sludge, 90 % dry...

level of fluorine in mains water (0.4 to 1 mg · L–1 depending on the climate of the country concerned) promotes the formation of tooth enamel and protects teeth from decay. On the other hand, too much...

– to take a hose), or again using compressed air (1 bar maximum); solid reagents: 25 or 50 kg sacks on pallets; metal, plastic or cardboard drums (e.g. for anhydrous ferric chloride); large...

initial pH recorded. Using a 1/10 mL burette, pour H2SO4 0.1 N until pH = 4, or V mL: or: M-alk. = V × 4 × 0.05 in g· L-1of CaCO3. VFA measurement Thereafter, pour H2SO4 0.1 N until pH = 3...

Trickling requires a 1 to 3 m height gravity fall. cascade This basic process (photo 2) is used when a gravity fall height of 1 to 2 metres is available and when a high level of effectiveness...

of pretreatment in 1 single work among our references Csepel (Hungary) 1,500,000 PE Xiamen (China) 1,200,000 PE La Feyssine (France) 300,000 PE Castelo Blanco (Portugal) 100,000 PE ...

with draught tubes. Sludge is extracted using a negative pressure siphon that is mounted on the bridge, and that transfers the sludge from the collection tank to a side channel. key figures 1, 2, or 3...

and sizing. The volumes discharged will vary depending on the dry-filling combinations and we can only provide rough values in this instance: acrylic fibres 35 m3·t–1; wool 70 m3·t–1; cotton 100 m3...

membranes instead of sand or dual media filtration. Rouen (France) (1,000 m3·h–1) constitutes the perfect example: processing karstic water and despite major quality variations (1 to 150 NTU), the treated...

and soil erosion etc. Waste that can be likened neither to purification sludge nor to grit produced by pre-treatment operations. On average, 10 L · hab–1·year–1 (or approximately 18 kg · hab–1·year–1...

of between 7 and 20 m · h–1 and up to 30 m · h–1 in specific designs; Aquazur T filters are used occasionally, especially in the event of a very tight hydraulic gradient. Photo 5. Aquazur filter – Air...