SU859327A1 - Method of waste water treatment - Google Patents

Description

(54) METHOD FOR PROCESSING WASTE WATER

The invention relates to wastewater treatment methods, including the treatment of sludge produced during purification. The known method is that the sediment of primary sludges formed during sewage treatment with 95% moisture mixed with uncured excess sludge wet 99.4% is fed into the mineralizer, where it is subjected to aerobic digestion, after which the mineralized mixture is compacted with Z-3 hours to a moisture content of 97.5%. The compacted mixture is sent to the center of the fugging, and the centrifugal prod uct formed during the centrifugation process is fed to the mineralizer D1, however, with a constant supply of the total volume of the centrate to the miner, i.e. when it is repeatedly recycled in sludge processing facilities (a secondary analyzer-centrifuge) biological purification system, there is an accumulation of dry matter, predominantly fine, not separable by centrifuging with suspensions. This leads to disruption of sludge treatment due to a decrease in the efficiency of separation of the solid phase by centrifugation, and the degree of mineralization by aerobic. fermentation. There is also known a method for treating sediments with mechanical and subsequent biological wastewater treatment, by which sediment of primary sedimentation tanks is subjected to dehydration by centrifuges, dehydrated sediment is fed for thermal drying, and the fugate mixed with non-depleted excess sludge is subjected to aerobic digestion for 6-8 days and condensed up to 97% of 3-5 hours. The compacted mixture is sent for centrifugation, with the centrifuge being fed to sludge beds for drying G2D. However, this method requires a significant amount of mineralizer and a large area for the construction of sludge sites. In addition, it is water, a department of & when compacted with an aerobic fermented mixture, it has a high content of COD contaminants and a high concentration of finely dispersed, difficult to settle suspensions. The supply of this water to biological treatment facilities requires an additional increase in their capacity. The purpose of the invention is to reduce the capacity of aeration facilities and the territory of the sites, increasing the degree of purification and cheapening the process. The goal is achieved by the fact that in a known method, including mechanical cleaning in primary settlers, biological cleaning in aeration tanks, sediment dehydration of primary settlers by centrifugation, thermal drying of dehydrated sludge, aeration of a fugate mixed with excess sludge, compaction of the mixture. thermal drying of the dehydrated mixture, dehydration of the centrate on sludge beds, resulting from the dehydration of the precipitate of a centrate mixed with excess sludge ne units are subjected to aerobic conditioning by aeration to a resistivity of (10-40) x 10 cm / g, the conditioned mixture is compacted and the condensed mixture is dewatered, and 2040% of the volume of the centrate is introduced into the wastewater before the primary sedimentation tank and 20 to 40% - to clarified wastewater before aerotanks. Biological sewage treatment facilities include a primary sediment tank, an aeration tank with or without a regenerator, and a secondary sedimentation tank. For compaction of excess sludge, an air cooler is used, and for aerobic conditioning - an air conditioner, which is an aeration tank of aeration type. Air conditioning mixture was compacted in a compactor, centrifugal dehydration, and thermal drying in a dryer. Excess sludge from the secondary sludge enters the sludge compactor, where it condenses to a moisture content of 98.5-99.0% within l-Z h. Sludge water is sent to the channel in front of the settling tanks and compacted excess sludge is fed to the air conditioner. The sediment from the primary settling tank is sent to centrifuges, the dehydrated sludge is fed to the drying apparatus, and the centrate is sent to an air conditioner. The mixture of centrifuge and excess compacted is subjected to aeration for 1-5 days to a specific resistance (10-40) x 10 cm / g. The conditioned mixture is compacted in a sealant for 5-6 hours to a moisture content of 95-96%. When compacted, the compacted liquid, the quality of which corresponds to water after complete biological treatment, is directed into the channel before the primary clarifiers or is mixed with the treated waste liquid from the secondary clarifiers before chlorination. The compacted conditioned mixture is fed to a centrifuge. The centrifuge formed by centrifugal dehydration of an aerobically conditioned compacted mixture is distributed as follows. A portion of the centrifuge in the amount of 20-40% of the total volume is mixed with the wastewater before the primary sedimentation tanks, part of it in the same amount is fed into the aeration tank, and the remaining quantity of the centrate is removed to the sludge beds. The solid phase, separated by centrifuging the aerobically conditioned mixture, is thermally dried in apparatus. The thermally dried sludge is directed to the place of storage or use. Example. The excess sludge is compacted with a moisture content of 96.6% to a moisture content of 98.5% for 2 hours. The mixture of compacted excess sludge and centrifuge from the centrifugation of sediment of primary sedimentation tanks is subjected to aerobic conditioning for 3 days to a specific resistance of 30x109 :: m / g, then compacted 5 hours to a humidity of 95% and centrifuged. At the same time, 20-40% of the total volume of the centrifuge is fed to the primary clarifier, 20-40% - into the aeration tank, and the remaining volume of the centrate is removed to the sludge bed. The table shows the main indicators of the technological process according to the proposed method (after centrifuging the aerobic-conditioned and compacted mixture into the primary settling tank and the aeration tank) in comparison with d known in terms of a station with a capacity of 100 thousand meters of wastewater. per day. Indicators Humidity of excess sludge,% Humidity of the mixture of excess sludge and centrifuge after centrifuging sediment of primary settlers supplied to the mineralizer,% conditioner,% Volume of the mixture supplied to the mineralizer, m / day conditioner m / day Duration of aeration of the mixture in the mineralizer, conditioner, days Capacity aeration structures for the treatment of sediments: mineralizer m air conditioner, m Humidity of the mixture compacted for 5 hours after aerobic treatment with mineralization,% of aerobic conditioning Volume of compacted mixture after aerobic fermentation mineralization, m aerobic conditioning concentration of contaminants in the liquid otde my COD, suspended solids mg, m sludge in the aeration tank Gain on dry substance, t / d

Total sediment and sludge

on dry matter t.d.

The resistivity of the centrate fed to sludge grounds 1G, cm / g

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Claims (1)

Claim Wastewater treatment method, including ⁴⁰ mechanical treatment in primary sumps, biological treatment in aeration tanks, / centrifugal dewatering of primary sedimentation tanks, thermal drying of dehydrated sludge <5, aeration of the centrate in a mixture with excess sludge, compaction of the mixture from melting, dehydration compacted mixture by centrifugation, thermal drying of the dehydrated mixture, dehydration of the centrate on sludge sites, characterized in that, in order to reduce aeration facilities and the territory of sludge platforms, to increase the degree of purification and reduction of the cost of the process, the centrate is mixed with excess sludge before compaction is subjected to aerobic conditioning to a specific resistance (U-DSSChk / cmL} with 20-40% of the centrate of the centrate being introduced into wastewater before the primary sump and 20-40% into clarified sewage in front of aeration tanks.