WO2013007847A1 - System for treating slurries by means of electrocoagulation and electrooxidation - Google Patents

Abstract

The invention relates to a system that consists of pumping the slurry from conventional storage ponds at pig facilities or farms toward a separator of solids and liquids, obtaining a solid that can be used as fertilizer and a liquid phase that is subjected to a flocculation process, wherein the muds obtained in said process are passed through a filter-press and the liquid is conveyed to an electrocoagulation apparatus, where the water undergoes electrolysis, the same apparatus separating floating sludge, precipitated sludge and clarified water. Said water is suitable for irrigation, since it contains a natural fertilizer; the floating sludge is conveyed to the filter-press; and the clarified water not used for irrigation is conveyed to a tank for further treatment in the subsequent phase. The fluid is subjected to a process of electrooxidation, filtering and finally a process of osmosis to separate the salts and the remaining impurities from the water and thus obtain a completely clean liquid.

Description

 PURINE TREATMENT SYSTEM THROUGH ELECTROCOAGULATION AND ELECTRQXIDACIQN

D E S C R I P C I O N

OBJECT OF THE INVENTION

The present invention relates to a slurry disposal system with use of the resulting water, whose obvious purpose is to perform a treatment of the slurries generated in pig farms and achieve the removal of impurities, to convert the original slurry into a fertilizer or fertilizer for the lands and to be able to take advantage of the resulting water, through appropriate equipment, for irrigation, cleaning and dumping.

BACKGROUND OF THE INVENTION

As is known, slurries are the mixture of feces, urine and washing water of the boxes or cochiqueras that are used in pig farms, being mandatory the existence of a slurry raft, to which they are channeled from the different points at which they are generated, so that the capacity of the raft will be adequate depending on the number of animals on the farm, to carry out a periodic emptying sufficiently distant in time.

In the treatment and elimination of slurry, fertilizers are obtained by means of which the fields are sprayed with the collaboration of a cistern carried by a tractor, which requires a large amount of soil to conveniently dose the slurry, also forcing This floor is available at the moment in which the emptying of the raft must be done.

DESCRIPTION OF THE INVENTION

The system that is recommended is based on a process of treatment of slurry, starting the treatment with the pumping of slurry from the corresponding storage raft of the farm itself, constantly under stirring by means of an agitator to keep the homogenate slurry leading to a separator solid-liquid press filter, obtaining a solid with 25-35% humidity and an effluent with particles between 0.5-0.2 mm, according to sieve, the solid obtained around 10% is used as a component in manufacturing of compost and solid fertilizers, being sent to a solids storage area, finally carrying out with those solids a drying phase if necessary, being able to perform said drying naturally outdoors or by forced air (aerobic method).

On the other hand, the liquid slurry obtained in the separator is subjected to a physical-chemical coagulation-flocculation process - by means of a DAF flotation device, where the floats obtained are floated to the surface by means of micro bubbles of dissolved air. The sludge formed by a mobile scraper system is removed from the tank. In said coagulation-flocculation process - the synthetic coagulant is injected at the entrance of the DAF equipment into a purin / coagulant mixer for continuous and homogeneous mixing of the slurry with the coagulant. Said coagulant does not modify neither PH nor the chloride content of the final result.

The duly coagulated effluent passes to the flocculation reactor where the flocculant is dosed (cationic acrylamide copolymer in aqueous dispersion) cationic type of low ionicity and high molecular weight. In this reactor it is slowly stirred at low revolutions for the formation of the flocculation and taken to the flotation tank by dissolved air, where a clarified and a sludge is obtained, this sludge is transferred to a press filter for dehydration, being mixed with the solids obtained in the solid-liquid separation process.

The effluent obtained in the DAF tank is passed through an electrocoagulation equipment, this equipment comprising three distinct parts, one corresponding to what is called a head, formed by an anode and a cathode, another corresponding to a sludge separation system , and another corresponding to a flocculant dosing system, so that the effluent is passed between the anode and the cathode of the electrocoagulation equipment, producing electrolysis of the same being collected at the bottom of the equipment by means of a funnel conical.

The treated water flows to the sludge separation system, where it is stored in a treated water tank and the separation between floating sludge, precipitated sludge and clarified water is performed, the floating sludge being removed by overflow and taken to the previously existing press filter. , while the precipitated sludge is emptied, by means of an automatic valve installed at the bottom of the tank and the treated water, it is automatically extracted by means of an electronic level control.

Through electrochemical treatment, in which by means of an electric current that passes through the fluid to be treated and with the collaboration of a sacrificial anode, chemical compounds are generated that separate or significantly reduce or eliminate solids, COD, nitrogen, phosphorus, metals heavy, etc. At this point of treatment of the slurry, water suitable for cleaning or use as a liquid fertilizer is obtained, with the following values:

- Reduction ± 90% of total nitrogen.

 - Phosphorus reduction, greater than 99%.

 - Heavy metal reduction, greater than 99%.

 - Elimination of viruses, bacteria, parasites, ecoli, legionella, etc. - Elimination of pesticides and phytosanitary products.

 - Elimination of organic matter, smell, color, solids.

This fluid is subjected to a following electro-oxidation process, increasing the pH with caustic soda.

In the aforementioned electro-oxidation process, the ammonium that the water carries is converted into ammonia, producing oxidation by the corresponding catalytic anodes, and whose oxidation is achieved based on hydrogen peroxide, ozone, hypochlorites and hydroxides.

After oxidation, the ammoniacal nitrogen is converted into nitrogen gas and soluble organic matter with release of CO ₂ , the liquid being sent to a zeolite and activated carbon filter, in which the color cleaning occurs, passing the liquid to be colorless

Finally, said colorless liquid is subjected to a reverse osmosis process, obtaining on the one hand the salts and the rest of impurities that leads to the liquid, and on the other hand totally clean water is obtained, and where the resulting analysis of this It results in the following: - Suspended solids 9 mg / 1

 - Sedimentable materials 10 ml / 1

 - Absent thick solids

 - COD 82.0 mg / 1

 - Conductivity 1,500 μ8 / αη at 20 ° C

- Absent color

 - Chrome III absent

 - Chromium IV absent

 - Nickel absent

 - Absent lead

 - Copper 0.28 mg / 1

 - Zinc 2.5 mg / 1

 - Sulfates 182 mg / 1

 - Total phosphorus> 2 mg / 1

 - Ammoniacal nitrogen 20 mg / 1

 - Nitric nitrogen 15 mg / 1

 - Absent oils and fats

 - Absent detergents

Said water obtained is a transparent liquid, odorless and suitable for any use.

DESCRIPTION OF THE DRAWINGS

To complement the description that will then be made and in order to help a better understanding of the features of the invention, according to a preferred example of Practical realization of the same, is accompanied as an integral part of said description, a single drawing where, for illustrative and non-limiting purposes, the following has been represented:

In the unique figure shown in the referenced sheet of drawings, the scheme corresponding to a block diagram of the different phases of the process of treatment and disposal of slurry object of the invention is represented.

PREFERRED EMBODIMENT OF THE INVENTION

As can be seen in the aforementioned figure, from the corresponding slurry pool with which the pig farm or farm must have the effect, the slurries are pumped to a separator or filter press (1) of solid and liquid, obtaining by a solid part that is sent to a storage tank (2) of solids. These solids (2) stored in the corresponding deposit, can be used, after drying either outdoors or by artificial processes, for fertilizers and land fertilizers while the liquid is sent to a flotation-flocculation tank (3), where a flocculation process takes place, with the addition of the respective flocculant through the corresponding dispenser (8). The action of this flocculant causes a precipitation of sludge in suspension to be generated, these being separated from the liquid and taken to the press filter to be pressed, and the sludge taken to the storage area thereof.

The effluent obtained is conducted to an electrocoagulation equipment (4) in which a head formed by an anode and a cathode, a sludge separation system, and a coagulant dosing system is established, taking place a water electrolysis. This electrolysis of metals and solid parts in suspension produces sludges that are in suspension and that are taken to the press filter, (1), where the pressing and drying of the sludge obtained in the electro coagulation process is carried out, being those sludge mixed with the solids obtained in the solid-liquid separation process.

The liquid obtained from the electrolysis process is collected in the lower part of said block or electrocoagulation equipment (4) the treated water is passed to a reservoir (5) the precipitated sludges of the electrocoagulation machine are purged, this water can be used as a fertilizer, since it is a completely sanitized component, without odor, and with a very important reduction of organic matter.

Finally, the resulting fluid or water treated in the manner described above is passed through an electro-oxidation step (6), increasing the pH, to obtain the oxidation of ammonium for conversion into ammonia, such that after this oxidation the ammoniacal nitrogen is converted into nitrogen gas and soluble organic matter with release of CO ₂ , the liquid being finally sent to a filtration phase (7) of zeolite-activated carbon, to produce the color cleaning of the liquid, to subsequently be subjected to a reverse osmosis phase (9) to separate salts and other impurities from the liquid, with respect to the completely clean water.

Claims

 R E I V I N D I C A C I O N E S

I ^a .- System of treatment of slurry by electrocoagulation and electroxidation, which based on compound of slurry stored in the corresponding rafts established for this purpose in the facilities or pig farms, is characterized in that from said raft the slurry is pumped to a solid separator -liquids or filter press (1), in which the solids that are sent to a storage container (2) for drying them outdoors or artificially to obtain fertilizer fertilizers for the land, while the liquids are sent to a flotation tank fio culation (3), a tank in which one sludge is generated and sent to the filter press (1), from which they are mixed with the solids from the storage tank (2), while the liquid matter is passed through an electrocoagulation equipment (4) for the separation of floating sludge, precipitated sludge and clarified water that is passed to a reservoir (5), the floating sludge being transferred by decantation and transferred to the press filter (1), while the precipitated sludge is purged, and the treated water passes to a process where caustic soda is added to increase the pH, to go to an electro-oxidation stage (6) and oxidation occurs through strong oxidants, so that the ammoniacal nitrogen obtained in the oxidation is converted into nitrogen gas and the soluble organic matter with release of CO ₂ , the resulting liquid being sent to a zeolite and activated carbon filter (7), to finally subject it to a reverse osmosis process (9) for separation of salts and impurities from treated and clean water.