FI64831B - PROCEDURE FOR DOSAGE AND PROCESSING OF CHEMICAL PROCESSING OF UTFAELLNINGSKEMIKALIER FOER RENING AV AVFALLSVATTEN I AVFALL - Google Patents

Abstract

A means by which the chemicals use in chemical effluent purification are dispensed into a flushing liquid e.g. in connection with the use of a toilet and the chemicals are efficiently mixed with the waste in connection with the flushing operation. The means utilizes a secondary flow from the filling flow of the waste flushing tank (1) achieved by the technology known in the art. The means comprises a dissolving vessel (8) containing undissolved precipitation chemical (9). The secondary flow from the filling of the flushing tank (1) entering the means through a pipe (6) becomes saturated during its passage through the dissolving vessel (8) to become a chemical solution, which is conducted into the flushing tank (1). The chemical solution that is formed in the flushing tank (1) becomes efficiently admixed to the waste in connection with the flushing of the waste. The point of connection of the pipe (6) going to the dissolving vessel (8) on the filling pipe (3) of the flushing tank (1) is located on the pipe run (15) after the valve (4) controlling the filling of the flushing tank (1).

Description

64831

Apparatus for the proportional dosing and rapid mixing of precipitating chemicals from waste water treatment into waste

The invention relates to an apparatus for the proportional dosing and rapid mixing of precipitating chemicals for waste water treatment, comprising an incoming pipe and a flow control member therein, a chemical dissolution vessel containing the chemical in solid form and utilizing a side flow into the dissolution vessel which dissolves the chemical into a substantially uniform solution, from which an amount equal to the side flow is due through the outlet pipe to the rinsing water.

10

In conventional chemical wastewater treatment, the wastewater is collected along a sewer to a treatment plant, where the precipitating chemical is usually metered in proportion to the flow-controlled incoming wastewater.

15

After the chemical dosing, a rapid mixing is performed in order to achieve an efficient mixing of the chemical mixture and the wastewater, in which case the coagulation reactions of the chemical and the waste material also take place. Rapid mixing is followed by agitation to flocculate the coagulation dispersion into descending flocs, which are separated in clarifiers. Conventionally, both rapid mixing, confusion and clarification take place in different pools or groups of pools. In small chemical treatment plants installed in septic tanks, the mixing and clarification rooms are not clearly separated.

Especially in the chemical treatment of small amounts of wastewater, the conventional process entails costs and inconveniences, especially with regard to the facilities required for the proper organization of treatment and maintenance. A significant improvement in the treatment of a small treatment plant is in the system described in: M. Branders, Effective phosphorus removal by adding 2,64831 alum to septic tank, Journal of Water Pollution Control Federation vol. 49, Nov. 1977, No. 11, p. 2285-2296, where the circuit breakers connected to the toilet flush lever controlled a chemical pump located in the basement of the apartment building. When flushing the toilet, the chemical-5 pump fed a standard dose of precipitating chemical into the outlet, from which the effluent was flushed with the chemical. Rapid mixing and agitation take place in the sewer leading to the septic tank and clarification takes place in the septic tank. However, the equipment arrangement has the following shortcomings: 10 - the required chemical pump makes the system expensive in the treatment of wastewater from an individual detached house - the efficiency of instant mixing depends on the slope of the sewer 15 and, as is usually the case in small treatment plants, insufficient mixing capacity impairs treatment results.

In wastewater treatment plants, chemicals are dispensed with solution pumps, various dry feed equipment, as in: Waste-20 water chemical treatment plant design 28-73, Finnish Association of Engineers, 1973 Helsinki, or with mechanical dispensing equipment, e.g. Information Center Association, 1976 Helsinki, is presented. It is also known to supply a chemical solution to a pressure-25 pipe by throttling the pipe by utilizing the pressure difference obtained by various types of equipment arrangements, such as Finnish Patent Application No. 269/62 and Finnish Patent Publication Nos. 22,273 and 26,869. In throttle-based systems, the accuracy of the chemical feed of the dosing devices is substantially dependent on the fact that the magnitude of the flow does not vary greatly.

Traditionally, the purpose of the additives added to the waste flush water has been to make the toilet flush water fresh-smelling, aesthetically beautiful in color and cleansing the toilet.

However, it is known that yeast that promotes biological cleaning of a septic tank can be added to toilet flush water, as disclosed in U.S. Patent No. 3,604,021. In the industry, a chemical has been added to process water 3 64831 in order to improve the treatment of process effluent, as disclosed in SE Patent No. 97449.

5 Known devices for dispensing a chemical into toilet flushing water are based on the following principles: - The chemical is placed in a toilet flushing water tank, where it either dissolves directly in the flushing water or is dispensed due to water surface variation as described in Finnish Publication No. 53,739.

- A piece of soluble chemical in the form of a solid is hung in a toilet bowl, where the chemical dissolves in the rinsing water during rinsing, as disclosed in U.S. Patent No. 3,604,021.

- A separate foot-powered chemical solution dosing pump is connected to the specially designed toilet with an intermediate tank, which feeds the chemical into the wastewater in the intermediate tank after the toilet basin 20 after flushing, as disclosed in U.S. Pat. No. 3,587,116.

It is an object of the invention to provide an improvement over the current known corresponding device solutions. It is a more detailed object of the invention to provide an apparatus for the proportional dosing and rapid mixing of precipitation chemicals in wastewater treatment with waste, in which apparatus the numerous drawbacks of the previously known solutions have been overcome.

The objects of the invention are achieved by a device which is mainly characterized in that the pipe entering the dissolution vessel is connected to the part of the pipe downstream of the valve controlling the filling of the flushing tank.

According to claim 2, the outlet pipe terminates in a turbulence zone of the filling flow of the flushing tank.

4,64831 The inventive step of the apparatus according to this application, which differs substantially from the known one, is precisely in that the additive to be fed is a precipitating chemical used in the chemical treatment of waste water, which is fed to the waste rinsing water to mix the chemical 3 with waste. This device arrangement makes the toilet space a chemical treatment room for a small treatment plant and the toilet seat a fast mixing structure for the treatment plant. The flocculation of wastewater takes place partly in the sewer and partly in the septic tank, where the settling dirt also accumulates. In the case of rinsing, an overdose of 10 chemicals is used so that unreacted chemical remains in the septic tank, causing dilute effluents from other wastewater sources to mix and become confused, mainly in the first compartment of the septic tank, forming a heavier waste floc that settles in the sludge sludge. By means of the apparatus of the invention, the efficiency of the operation of the septic tanks 15 can be carried out in a simple, reliable and inexpensive manner.

The characteristics of the device structure are based on the connection point of the device, which is in the pipe section downstream of the 20 valves controlling the flushing of the waste or the filling of the flushing tank. This results in the following characteristics of the chemical dosing device: - The flow rate is constant and stable, so the proportional dosing is accurate.

25 - The solution tank can be depressurized by placing it at a higher level than the waste rinsing tank, from which the chemical dose flows by gravity into the rinsing agent.

The device according to the invention is particularly well suited for the chemical treatment of waste water under the following conditions: - property-specific waste water treatment in a detached house area 35 - increasing the treatment capacity of existing septic tanks -

The invention will be explained in detail with reference to the principle solution shown in the figure of the accompanying drawing, to which, however, the invention is not intended to be exclusively limited.

The drawing figure shows a schematic side view of a preferred embodiment of the device according to the invention.

10 The figure shows an application example of the device according to the invention, in which the precipitating chemical used for chemical treatment of wastewater is fed to the flushing water 14 of the toilet seat flush tank 1. In connection with flushing the closure 5 waste in the toilet seat. As the water level in the flushing tank decreases, the float valve 4 opens, whereby water flows into the flushing tank 1 along the pipe 3 connected to the pressurized water supply network for the next flushing. A throttle member 2 is installed in the pipe section 3 after the float valve 20, which restricts the filling flow of the flushing tank so much that sufficient pressure is applied to the line between the throttle member 2 and the float valve 4 to transfer the the surface of the solution 11 is 25 higher than the surface 14 of the flushing tank liquid. The pipe 6 entering the dissolution vessel 8 has a flow control member 7 with which the magnitude of the side flow can be adjusted as desired.

The chemical dissolution vessel 8 has the chemical 30 9 on top of the filter structure 10 as a substantially chemical saturated solution 11. The side flow of the rinsing tank 1 into the dissolution vessel b through the tube 6 causes an equal amount of substantially saturated solution 11 conductive put-35 keen 12.

6 64831

When the flushing tank 1 is filled, the float valve 4 closes and both the filling flow and the side flow through the solution vessel 8 cease. When the rinsing tank starts to fill after the next rinsing, the side flow through the solution vessel 8 leads to the next dose of chemical solution to the rinsing tank 8.

It is clear, however, that the invention is not limited to an exemplary structure or an exemplary application, but may vary within the scope of the appended claims. In this case, for example, the supply point of the chemical to the rinsing water or the rinsing structure may differ from the exemplary structure.

Claims (2)

64831 An apparatus for proportionally dispensing and rapidly mixing precipitating chemicals for wastewater treatment, comprising an inlet pipe (6) and a flow control member (7) therein, a chemical sounding vessel (8) with a solid chemical (9) and an apparatus utilize in a known manner the filling flow of the flushing tank (1) or the flush flow by adjusting the pressure difference obtained by throttling the adjustable dissolution vessel (8), which dissolves the chemical (9) into a substantially homogeneous solution (11). ) 10 to the rinsing water, characterized in that the pipe (6) entering the dissolution vessel (8) is connected to the pipe section (15) downstream of the valve (4) controlling the filling of the rinsing tank (1). Device according to Claim 1, characterized in that the outlet pipe (12) terminates in the turbulence zone of the filling flow of the flushing tank (1).