RU2163573C1 - Plant for liquidation and utilization of sludge from settling basins of cities and industrial enterprises - Google Patents

Abstract

FIELD: liquidation and utilization of sludges; applicable in production of organomineral fertilizers and separation from sludge of metal compounds, including those of heavy metals. SUBSTANCE: plant combines two groups of equipment ensuring two-stage processing of sludge. The first stage includes unit of sludge thinning, process activation unit ensuring transition of harmful substances into solution, unit of separation and gathering of pulp containing organic substances and sand, and equipment unit for production of granulated organomineral fertilizers. The second stage has the second unit for process activation in which solid phase is settled under effect of additives, and unit for separation and gathering of sediment containing metal compounds. The invention provides for reliable neutralization and utilization of sludges of municipal settling basins, settling basins of industrial enterprises and industrial dumps with simultaneous production from municipal sludges of pellets of organomineral fertilizers and concentrates of metal compounds from all settling basins and sumps. EFFECT: higher efficiency. 3 cl, 1 dwg, 1 tbl

Description

 The invention relates to the field of liquidation and disposal of sludge and can be used for the production of organic fertilizers and the separation of metal compounds from sludges, including heavy ones.

 Known methods and installations for the neutralization and disposal of domestic and industrial wastewater, including sludge formed in sumps, mats and aeration tanks [1-2].

 Very serious drawbacks of these systems are large dimensions, insufficient degree of purification, slow separation of precipitation, lack of a clear interface between the liquid and solid phases, and others.

 The closest is the installation for the collection, processing and disposal of soils [3]. The unit is equipped with a unit for collecting and pumping bottom sediment, a unit for cleaning water-sludge suspension and cultivation of biological strains, a unit for comprehensive soil cleaning with aerobic and anaerobic microorganisms, and a unit for biomass utilization.

 The specified installation cannot be used to eliminate sludges that contain large amounts of sand and solid organic and inorganic components. There is no unit in the installation for preliminary processing of materials; nodes are not provided for the allocation of organic sediments and their conversion into useful products.

 The aim of the invention is the reliable neutralization and disposal of sludge from urban sumps, sumps of industrial enterprises and industrial dumps with the simultaneous receipt of urban sludge granules of organic fertilizers and concentrates of metal compounds from all sumps and dumps.

 The problem is solved as follows.

 In the installation for the elimination and disposal of sludge from the settlers of cities and industrial enterprises, containing a sludge liquefaction unit, a system for separating solid and liquid phases, compaction and dewatering of sludge, according to the invention, the installation combines two groups of equipment units providing two-stage sludge processing, the first stage includes a sludge liquefaction unit, a process activation unit for transferring harmful substances into a solution, a unit for separating and collecting pulp containing organic matter and sand, and a unit equipment for producing granular organic fertilizers, including a hopper for pulp containing organic matter, a pressing screw with two or three nozzles for introducing lime and mineral additives, a dryer, a hopper, a filling machine, containers for additives, and the second stage contains a second activation unit processes in which, under the action of additives, a solid phase precipitates out, a separation and collection unit for a precipitate containing metal compounds.

 The sludge liquefaction unit before processing contains a screw with a varying angle of inclination of the working part and a hopper for the prepared slurry with a dispenser.

 The liquefaction unit, consisting of a hopper and auger, is equipped with a guide pipe for supplying circulating water, integrated at a distance of one third from the receiving part of the auger.

 Hardware-technological scheme for the destruction of sludge is presented in the drawing.

 The installation contains a screw 1 with a fitting for introducing recycled water 2, a hopper 3, an installation for activating processes 4, tanks for additives 5, 6, a pump 7, an intermediate tank 8, settling tanks 9, 10, a second installation for activating processes 11, tanks for additives 12, 13, 14, an intermediate tank 15, sumps 16, 17, sludge traps 18, 19, a receiving hopper 20, containers for mineral additives 21, containers for powdered lime 22, a pressing screw 23, dried 24, a storage hopper 25, a filling machine 26 and recycled water line 27. Sludge source - map 28.

 Installation works as follows.

 From the card (sludge storage) 28, with a screw 1, sludge is fed into the hopper 3. At the same time, to circulate it through line 27 through the nozzle 2, circulating water is supplied. From the hopper 3, the pulp with additives from containers 5, 6 (if necessary) by gravity enters the process activation apparatus 4, in which harmful substances (usually metal compounds) pass into the solution. The pulp is sent to the intermediate tank 8, where the main part of the solid phase (sand) is separated. The pulp, freed from large inert particles, is pumped into the sumps 9 and 10 by the pump 7, the sludge from which is accumulated in the sludge collector 19, and then sent to the hopper 20. From the hopper 20, the sludge goes to the pressing screw 23 together with lime powder and mineral additive coming from the tanks 21, 22. During movement in the screw 23, the mixture gradually loses fluidity and turns into a thick mass, which is pressed through filters and in the form of cylinders with a diameter of 5-10 mm is sent for ripening and drying in the dryer 24. The granules solidify due to chemical iCal reactions and requires virtually no power consumption. The solid granules are discharged into the storage hopper 25 and packaged using an automatic machine 26. The solution, separated from the solid phase from the settlers 9, 10, is sent to the installation 11, and first additives are added to it in the form of milk of lime, sulphurous iron and other containers 12, 13, 14. When processed in the installation 11, a solid phase precipitates from the solution, consisting mainly of metal hydroxides. Phase separation is carried out in series tanks 15 and sumps 16, 17. Precipitated sludge is accumulated in sludge collector 18 and sent for processing. Purified water through line 27 is diluted to the head of the process. Thus, a closed process is carried out, the products of which are organic fertilizers and a concentrate of metal hydroxides. There are no emissions after sludge destruction.

 Example.

 Silt from settling tanks of one of the Moscow aeration stations was used as a feedstock. The silts were very thick, smelled unpleasantly and contained a large amount of solid residues, apparently of organic origin. One device of the UAP-1V-2 type was used, with a productivity of 10-12 t / h in water. Productivity of this type of apparatus for undiluted sludge approaches 5-8 t / h. The technological scheme differed from the proposed one in that the process went periodically - in two stages. Initially, a batch of sludge was processed to separate sand and organic sludge from the solution. At the second stage, the solution was processed in the same apparatus for the separation of metal hydroxides.

 Before feeding into the working area, a quantity of water was added to the sludge so that it flows freely through the pipe. The initial humidity was 83%; sand content - 30%; organics - 35.6%.

 The results of two-stage sludge treatment are presented in the table.

 The metal content in the organic sediment corresponds to the MPC.

 A possible excess of the MPC standards in purified water is not significant, since it completely goes to liquefy sludge and does not leave the production line.

 The metal content in the organic sludge and in purified water is often reduced thousands of times in one cycle. At the same time, all products received are completely disinfected. There is no chemical or thermal pollution of the environment.

 The installation is characterized by low material and energy consumption, occupies small production areas.

 The UAP-1V-2 type installation provides silt productivity of 25-50 thousand tons / year. If necessary, productivity can be increased.

 There is a mobile installation option.

 The installation can be used to neutralize and dispose of domestic and industrial effluents. After the destruction of sludge in one city or at one enterprise, the installation can be sold or leased.

Sources of information
1. S.V. Yakovlev, Y.A. Karelin, Yu.M. Laskov, V.I. Kalitsun. Wastewater and wastewater treatment, M .: Stroyizdat, 1996.

 2. B. S. Xenophon. Sewage treatment. Flotation and thickening of precipitation. Publ. Chemistry, 1992.

 3. RU 2075447 C1.

Claims (3)

 1. Installation for the elimination and disposal of sludge from the settlers of cities and industrial enterprises, containing a unit for diluting sludge, a system for separating solid and liquid phases, compaction and dewatering of sludge, characterized in that it combines two groups of equipment units that provide two-stage processing of sludge, the first the step includes a sludge liquefaction unit, a process activation unit providing the transfer of harmful substances into the solution, a unit for separating and collecting pulp containing organic matter and sand, and the unit is equipped for obtaining granular organic fertilizers, including a hopper for pulp containing organic substances, a pressing screw with two or three nozzles for introducing lime and mineral additives, a dryer, a storage hopper, a filling machine, containers for additives, and the second stage contains a second activation unit processes in which, under the action of additives, a solid phase precipitates out, a separation and collection unit for a precipitate containing metal compounds.  2. Installation according to claim 1, characterized in that the sludge liquefaction unit before processing comprises a screw with a varying angle of inclination of the working part and a hopper for the prepared slurry with a dispenser.  3. The installation according to claim 2, characterized in that the liquefaction unit, consisting of a hopper and auger, is equipped with a guide pipe for supplying circulating water, integrated at a distance of 1/3 of the receiving part of the auger.

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