298 94 307/02 Untersuchungen zum Stand der Umsetzung des ...
Teilen Einbetten Melden
ePaper herunterladen

298 94 307/02 Untersuchungen zum Stand der Umsetzung des ...

298 94 307/02 Untersuchungen zum Stand der Umsetzung des ... 298 94 307/02 Untersuchungen zum Stand der Umsetzung des ...

bvt.umweltbundesamt.de
von bvt.umweltbundesamt.de Mehr von diesem Publisher
03.12.2012 Aufrufe

Specific O2 consumption for N 1,91 kg O2/kg BOD Flow of return sludge 43 % Teil 3 Seite 4-35 The introduction of air and the circulation of the biomass are achieved using 8 aerator chains. The aerator chains consist of 7 floating aerators each, connected to one another by means of air supply hoses. The air is introduced in the form of small bubbles, over the basin floor. The required quantity of air is made available through sliding vane rotary com- pressors. A compressor constantly runs on base load in order to ensure a specific mini- mum level of circulation of the activated sludge. The connection of further compressors is regulated by a timing programme and an automatic oxidation/reduction control. By vary- ing the rate of oxygen introduced through different chains aerobic and anoxic zones are produced. The rate of oxygen fed through the chains is altered periodically, so that over time anoxic zones are intermittently created throughout entire basin. The sludge is removed and the effluent is subject to further aeration and sedimentation. Table 4-6 shows the emission levels achieved in the plant described in Table 4-5 during the period 1992 to 1996. Table 4-6: Emission levels achieved during the period 1992 - 1996 Parameters Aver- BOD5 homogenised mg/l COD homogenised mg/l age Minimum Maxi- mum 3.1 1 8 65.4 35 125 NH4-N mg/l 10.0 0.3 29 NO3-N mg/l 2.4 0.3 7.7 NO2-N mg/l 1.8 0.7 4 P total mg/l 1.8 0.3 4.3 AOX mg/l 0.015 < 0.01 0.02 At a second rendering plant reportedly designed with a processing capacity of 580 t/d of animal carcases and designed for full nitrogen elimination, 2 tanks are operated in parallel with intermittent aeration. The process effluent is subject to fat separation and flotation followed by mixing with non-process waste water. It is then treated in a clarification plant and an equalisation basin (1.250 m³ with a reserve of 1.750 m³). It is then divided be- tween 2 basins, each of 6.240 m³ capacity. The basins contain 1.365 meter tubes for air intake, aerators and 3 stirring devices. The basins are in alternation supplied with air (aer- ated) at or simply stirred (anoxic) to time ratio of approximately 2:1.

Teil 3 Seite 4-36 At a slaughterhouse a WWTP treats effluent from the slaughterhouse, which has a tripe processing plant, in which intestines and stomachs are cleaned out and prepared for fur- ther processing. Stomach and intestinal contents, as well as blood are also handled. The slaughterhouse has a capacity of 25000 cattle per week, i.e. 5000 per slaughter day. This produces 200 litres of effluent per slaughter unit, i.e 623 l/t cattle carcase. It is reported that the daily load treated by the WWTP is BOD5 2020 kg, TKN 360 kg and 18 kg phosphorus. Two activation basins are used, alternating 1.5 – 2 hours denitrification with 1.5 – 2 hours nitrification. The times are controlled by monitoring NH4-N, NO3-N and O2 and adjusting the pressure aeration rate. Table 4-7 Dimensional and operating data of the aerobic treatment stage of this plant Total volumes, aeration tank (VBB) 7000 m³ Mixed-liquer suspended solids in the aeration tank (TSBB) 4 – 5,3 g/l BOD – load (Bd-BOD) 2.020 kg BOD/d TKN (Kjeldahl-nitrogen) – load (Bd – TKN) 360 kg TKN /d pH 6,8 – 7,2 BOD – volume load (BR - BOD) 0,29 kg BOD/(m³·d) TKN – volume load (BR – TKN) 0,051 kg TKN /(m³·d) BOD – sludge load (BTS – BOD) 0,072 kg BOD /(kg TS·d) P – sludge load BTS (BTS - P) 0,00064 kg TKN /(kg TS·d) TKN – sludge load BTS (BTS - N) 0,012 kg TKN /(kg TS·d) Excess sludge incidence TSÜS 66 kg/d Age of sludge tTS Mixed-liquer suspended solids in return sludge (TSRS) 30 - 40 d 7 – 11 g/l By this method the maximum emission levels measured between 1995 and 1997 are shown in Table 4-8.

Teil 3 Seite 4-36<br />

At a slaughterhouse a WWTP treats effluent from the slaughterhouse, which has a tripe<br />

processing plant, in which intestines and stomachs are cleaned out and prepared for fur-<br />

ther processing. Stomach and intestinal contents, as well as blood are also handled.<br />

The slaughterhouse has a capacity of 25000 cattle per week, i.e. 5000 per slaughter<br />

day. This produces 200 litres of effluent per slaughter unit, i.e 623 l/t cattle carcase. It is<br />

reported that the daily load treated by the WWTP is BOD5 2<strong>02</strong>0 kg, TKN 360 kg and<br />

18 kg phosphorus. Two activation basins are used, alternating 1.5 – 2 hours denitrification<br />

with 1.5 – 2 hours nitrification. The times are controlled by monitoring NH4-N, NO3-N and<br />

O2 and adjusting the pressure aeration rate.<br />

Table 4-7 Dimensional and operating data of the aerobic treatment stage of this plant<br />

Total volumes, aeration tank (VBB) 7000 m³<br />

Mixed-liquer suspended solids in the<br />

aeration tank (TSBB)<br />

4 – 5,3 g/l<br />

BOD – load (Bd-BOD) 2.<strong>02</strong>0 kg BOD/d<br />

TKN (Kjeldahl-nitrogen) – load (Bd –<br />

TKN)<br />

360 kg TKN /d<br />

pH 6,8 – 7,2<br />

BOD – volume load (BR - BOD) 0,29 kg BOD/(m³·d)<br />

TKN – volume load (BR – TKN) 0,051 kg TKN /(m³·d)<br />

BOD – sludge load (BTS – BOD) 0,072 kg BOD /(kg TS·d)<br />

P – sludge load BTS (BTS - P) 0,00064 kg TKN /(kg TS·d)<br />

TKN – sludge load BTS (BTS - N) 0,012 kg TKN /(kg TS·d)<br />

Excess sludge incidence TSÜS 66 kg/d<br />

Age of sludge tTS<br />

Mixed-liquer suspended solids in return<br />

sludge (TSRS)<br />

30 - 40 d<br />

7 – 11 g/l<br />

By this method the maximum emission levels measured between 1995 and 1997 are<br />

shown in Table 4-8.

logo

Produkte

Ressourcen

Unternehmen

AGB
Datenschutzerklärung
Cookie-Richtlinien
Cookie-Einstellungen
Impressum
Change language
Made with love in Switzerland
© 2024 Yumpu.com all rights reserved

Hurra! Ihre Datei wurde hochgeladen und ist bereit für die Veröffentlichung.

Erfolgreich gespeichert!

Leider ist etwas schief gelaufen!