DE2211890A1 - Waste water purification - using conc hydrogen peroxide forming nascent oxygen recombined for biological purification - Google Patents

Abstract

Chemical and biological purification of waste waters by introducing O2 is effected by (1) using as O2-source, highly concentrated, e.g. 80-85%, H2O2 which is either (ae mixed directly with the concn. waste water in a container of suitable material, e.g. pure Al or plastic-lined material; is catalytically decomposed in the presence of heavy metals with nascent O reacting immediately with the waste water to be purified or, (b) in the absence of catalytically active substances, is decomposed directly before entry into container by means of suitable catalysts; (2) in order to enrich the waste water with O2 for biological purification, the H2O2 is decomposed by suitable catalysts before entering receiving stream and the supply of O2-enriched water into biological clarification plant system takes place only after re-combination of nascent O to O2.

Description

J2rfailrn 7i 'Purification of Sewage Increasing Pollution of rivers and lakes due to insufficiently treated sewage makes it necessary that methods are used that are capable of using a relatively small amount of space are harmless, especially industrial contamination in a small space do. Normally there are a) undissolved inorganic substances in the wastewater and organic in nature and b) solutes of both types.

The removal of the undissolved matter is generally mechanical caused by sand traps, settling basins, septic tanks and rinsing strainers, while the specifically lighter suspended solids cannot be removed by this method. By adding chemical clarifiers such. B. milk of lime or aluminum sulfate the sedimentation of these suspended solids is accelerated, but they fall In addition, these additives can destroy the receiving water damage. The organic impurities mean by their consumption of oxygen a danger to fish farming in the receiving waters. Are nitrogenous compounds and carbohydrates in sewage, so can smelly putrefaction and secondary putrefaction appear. In the case of biological cleaning, the organic ones are destroyed Substance produced by microorganisms in the presence of oxygen. It has now been shown that, especially due to the increasing use of detergents, by simple Blowing in air or oxygen, the necessary enrichment of the wastewater with oxygen cannot be reached or only incompletely.

The object of the present invention is to enrich the wastewater to effect with oxygen, being separated after once the oxidizing effect of oxygen in the status nascendi in that area of the wastewater in which the bioligisc, he No cleaning due to the presence of substances harmful to organisms is possible, and in the further by enrichment with no longer nasal Oxygen in that part of the system that is intended for biological cleaning.

It is known that the oxidizing process of chloroxides is also known used for wastewater treatment. However, this procedure is not permitted if that Wastewater contains phenols, as the chlorine released with the phenols is chlorophenol forms, which makes the purified water inedible. The disadvantage is with Avoid using highly concentrated hydrogen peroxide.

The application of the nascent oxygen is expediently carried out in one closed plant in which the to be treated, already by mechanical means Thickened wastewater with a high part of the snake kept in motion by stirrers etc. will. The highly concentrated hydrogen peroxide is either porous, ceramic Plates introduced directly into this vessel, with a fine distribution of the emerging Hydrogen peroxide is ensured by the structure of the pores, or it becomes through a catalyst bed that is in direct contact with the wastewater, pressed and catalytically decomposed. The first case is for the decomposition of the Mittal the presence of catalytically or chemically acting on the hydrogen hydroxide Substances on the sludge prerequisite, e.g. B. heavy tales, while in the second case the wastewater can be free of such substances. In both cases arises immediately nascent oxygen next to water in the area of the mud.

The heat of decomposition released by the hydrogen peroxide accelerates the processes of oxidation. The amount of hydrogen sulfide to be decomposed and the residence time of the wastewater in the closed system depends on the type of the sludge to be oxidized. This can be done by known apparatus Time can be determined exactly. The hydrogen peroxide is expedient in concentrations from 80 to 85 46 applied. The introduction into the closed vessel can either due to the static pressure of the hydrogen peroxide column when the container is at a high level happen or be carried out with the help of metering pumps. Containers and pipelines, that come into contact with the hydrogen peroxide, must from Reinalu exist or by-suitable plastic covers against the attack of the agent be protected.

The following formation of the initiation process also appears expedient : The agitator blades that circulate the sludge contain channels that connect with that of the Wassarstoffauperoxyd feeding hollow shaft are in connection. These channels are one-sided to the vessel to with z. B. porous, keromic material covered through which the hydrogen superoxide is squeezed. Such a device will provide optimal mixing of sludge and hydrogen peroxide guarantee.

When using a catalyst bed to decompose the hydrogen peroxide, So if the substances causing the decomposition are missing in the sludge, a Sieve system made of silver wire or Sleiplatten with a coating of lead peroxide need. These beds can be placed directly in the supply duct immediately before entry be inserted into the vessel.

To enrich the wastewater lit oxygen for the biological Cleaning, this must not be in the status nascendi, as it is in the case of di @@@@ which would damage the microorganisms.

This is the reason for the decomposition of the hydrogen peroxide outside of the receiving water. Between Zer @ etzer and entry of the enriched with Bauurutoff Water in the receiving water, a pipe line is switched, the length of which is measured is that depending on the flow rate of the water / oxygen mixture a recombination of the nascent Sausratoffa to normal @ n, mol @ kuleren oxygen @ can be done.

Claims (2)

P a t e n t a n s p r ü c h e Process for the chemical and biological purification of waste water by Introducing oxygen, characterized in that 1) as an oxygen supplier highly concentrated hydrogen peroxide is used, which is in a suitable bEterial existing container either directly with the thickened Ao water mechanically mixed and catalytically decomposed by these in the presence of heavy metals and the nascent oxygen directly-with the wastewater parts to be cleaned reacts or in the absence of catalytically active substances immediately before the Entry into the container is decomposed by suitable catalysts. 2) to enrich the wastewater with oxygen for the biological Purification of the hydrogen peroxide using suitable catalysts before entering the receiving water is decomposed and the feed line is enriched with oxygen Water in the part of the plant intended for biological clarification only after recombination from nascent oxygen to molecular oxygen.