CS215356B1 - A method for removing non-sucrose from dietary juice by stabilizing the sludge conglomerates in the juice from the first saturae and the apparatus for performing the method - Google Patents

Abstract

The method of removing non-sugars from diffuse juice with stabilization of sludge conglomerates in the juice from the first saturation relates to the sugar industry. The purpose of the invention is to achieve highly favorable physicochemical properties of the turbid juice from the first saturation and thereby enable a significant increase in the performance of the equipment for sludge separation, both thickening filters and decanters without post-filtration, high quality of light juice and low sensitivity of the process to changes in the technological quality of beets. The stated purpose is achieved by a complex distribution of the final clarification dose of CaO in the ratio: final clarification:: second stage of first saturation: second saturation 6:2:1. 50% of the turbid juice from the first saturation is recirculated to the pre-clarification, sludge conglomerates are formed, which are stabilized in the second stage of the first saturation by packing calcium carbonate at the optimal pH of the first saturation, while acquiring very favorable physicochemical properties.

Description

The invention relates to a process for removing non-sugars from diffuse juice with stabilization of sludge conglomerates in juice from the first saturation and to an apparatus for carrying out the process.

In recent years, the purity of diffuse juice, which contains an increased amount of non-sugars, has decreased, making epuration procedures to remove them more and more difficult. In modern sugar refinery, it is no longer sufficient to use the existing epuration methods. New, powerful sludge separation devices from the first saturated juice place considerable demands on the physicochemical properties of the saturation sludge (filterability, sedimentation rate). From this point of view, many epurational procedures have been developed, but they do not solve the problem in a comprehensive way. The problem of the most punctual way of juice cleaning is very demanding and sensitive, it depends on many, often contradictory effects and mainly on technological quality of beet. However, the technological quality of beet varies every year, it is different at the beginning and different at the end of the campaign, but often changes several times a day. It would therefore seem that it is not generally possible to develop a certain juice purification procedure, one which is, to a large extent, insensitive to changes in the technological characteristics of the beet, economical while guaranteeing good juice purification and good sugar refinery work.

The method of CaO addition is decisive for the resulting quality of the light juice and the good physicochemical properties of the saturating sludge. The existing methods of CaO addition to the whole epuration are not solved optimally and comprehensively, there is a considerable dissolution of already precipitated colloids and therefore the results are very fluctuating. To date, the maximum utilization of all known beneficial effects of CaO, the adsorption properties of calcium carbonate, and the hydraulic effect on coragulated particles have not been sufficiently solved in the existing epuration processes.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a process for removing non-sugars from diffuse juice which comprehensively exploits the knowledge of lime, its addition, adsorbing effects of calcium carbonate and hydraulic effect on the formed sludge particles. I. saturation, at the same time allowed to achieve high quality of light juice, low sensitivity to changes of technological quality of beet, easy process control, low attendance and possibility to use sludge separation of both thickening filters and decanters without using polyelectrolytes and without filtration of decanted juice.

This object is solved by the invention, which is a method of removing non-sugars from diffuse juice with stabilization of sludge conglomerates in juice from the first saturation, and its essence consists in complex distribution of the CaO finish with fixed dividing edge in ratio: and II. a saturation of 11%, and in the stabilization of the sludge conglomerates in the second stage of the first calcium carbonate saturation.

Process for removing non-sugars from diffuse juice with stabilization of sludge conglomerates in juice from I.

The saturation according to the invention consists in passing the diffuse juice into a pre-clarifier, where it is progressively pre-treated with lime milk to a pH of 11-11.5 at a temperature of 50-55 ° C. Recirculation of 50% sludge from the first saturation (divided by a fixed overflow edge 1: 1 at the outlet of the first stage of the first saturation) and the thickened sludge from the II. saturation. In this pre-treatment area, the colloidal particles that pass through the metastable phase are adsorbed onto the calcium carbonate particles present. Upon heating to 90 ° C, further addition of CaO-67% finish, and saturation to an optimum pH of 10.8-11.2 in the first saturation stage, adsorbent complexes of colloidal impurities and calcium carbonate conglomerates are formed in the juice. These are then subjected to the hydraulic effect in the second stage of the first saturation, where it is fed and simultaneously saturated with CaO in a weight corresponding to the weight of CaO required for pre-clarification (i.e. 22% of the CaO finishing dose). In this second stage of the first saturation at an optimum pH of 10.8—11.2, the carbonate particles and the present sludge conglomerates converge, the calcium carbonate packs on the sludge conglomerates, thereby increasing them and forming a coarse-grained precipitate which has an excellent filtration capability and high sedimentation rate (Fk values below 1 and Sk above 12 cm were achieved in the full scale). The carbonate coating prevents the previously adsorbed and precipitated colloidal impurities from returning to solution. The process taking place in the second stage of saturation can be called “stabilization of adsorption complexes of colloidal impurities and conglomerates of calcium carbonate - calcium carbonate”, in short: “Stabilization effect in the first saturation”. The purification process with a complex CaO distribution can be referred to as "complex epurae".

The resulting saturation sludge, due to its physicochemical properties and low ability to release non-sugars back into solution, fully complies with the operating conditions of both thickening filters and decanters without filtering off the decanted juice. The remaining portion of lime (11% of the CaO finish) is added to the filtered or decanted juice. Adsorption properties of calcium carbonate from II. saturation is further utilized in recirculation to pre-clarification. The resulting epuration effect is above 40%, indicating that very good quality light juice is obtained.

The total CaO addition depends on the non-sugar content of the diffuse juice (80-90%) and is divided as follows: into the pre-finer 16.5%, into the finer 55.5% (67% of the final batch); to the second degree of I. saturation 18.5% (22% of the finishing dose); do II. saturation 9.5% (11% of the final batch). The total amount of CaO is measured and is divided into a pre-refining dose and a refining dose. The post-lime batch is fed to a divider as shown in the drawing, which is a container having a built-in fixed edge I divided 6: 2: 1 by auxiliary solid and stationary blades 2 and 3 which enable the post-lime CaO %, to the second degree of I. saturation 22% and to II. saturation 11%. The complex distribution of lime makes it possible to dispense CaO into II. saturation without separate measuring device.

The described process for the purification of diffuse juice with stabilization of the sludge conglomerates from I. saturation can be advantageously used in all plants of the sugar industry. It does not increase the demands on operating personnel or requires expensive investments, increases the performance of all sludge separation equipment, and in practice has proved to be less sensitive to changes in the technological quality of beet.

Example 1

The diffuse juice is passed through barometric heaters to a pre-scrubber, where it is progressively pre-treated with lime milk to a pH of 11-11.5 at 50-55 ° C. Recirculation of 50 vol% of the turbid juice from the first stage of the first saturation and the concentrated sludge from the II. saturation. The pre-clarified juice is passed through the pump through the heaters II. stage, where it is heated to 90 ° C in the afterburner, where it finishes with 67% CaO. From the clarifier, the finished juice falls into the first degree of saturation, where it is saturated to the optimum pH of 10.8-11.2. The turbid juice at the outlet of the first degree of saturation is divided by a 1: 1 overflow edge. Half of the juice is used for recirculation to the pre-clarifier and the other half is stabilized in the second degree of saturation. In this second stage, simultaneous saturation takes place at an optimum pH of I. Saturation of 10.8-11.2, with a simultaneous metering of 22 vol% of the final CaO batch. This is followed by separation of the sludge and dosing of 11.1% by volume of the final CaO batch into the filtered first saturated juice before II. saturation.

Example 2

The diffuse juice is passed through barometric heaters and II heaters. degree, where it is heated to 90 ° C, to a fining column DK, where it is pre-treated with lime milk in the first four zones to a pH of 11-11.5. Lime milk is not added to the second zone but recirculated turbid juice from the first degree of saturation is introduced. In the remaining two zones, finishing is carried out by introducing into each zone half of the 67 volume% of the finished CaO batch. From the fining column DK, the clarified juice falls into the first degree of saturation, where it is saturated to an optimum pH of 10.8-11.2. At the outlet of the first stage, the turbid juice is divided by a 1: 1 overflow edge, with 50% of the juice being fed into the antifoam container and by pump into the second zone of the fining column DK. The second half of the first saturated juice is fed to the second degree of saturation, where it is saturated to optimal alkalinity while adding 22 vol% of the final CaO batch. This is followed by separation of the sludge and dosing of 11.1 vol% CaO from the final batch into the filtered juice before II. saturation.

Claims (2)

SUBJECT Method for removing non-sugars from diffuse juice with stabilization of sludge conglomerates in juice from the first saturation, characterized in that the CaO finish batch is continuously and comprehensively distributed by adding 55-80 vol%, most preferably 67 vol% of the finish batch into the finisher. CaO, to the second stage of the first saturation of 10 to 35 vol%, most preferably 22 vol% of the final caO batch, and to the second saturation of 10 to 35 vol% BACKGROUND OF THE INVENTION% by volume, most preferably 11% by volume of the afterburning batch of CaO. 2. A device for the continuous and complex distribution of a caO batch, characterized in that it consists of a container with a fixed fixed fixed dividing edge (1) which is divided in a ratio of 6: 2: 1 by auxiliary fixed fixed edges (2) and (3) .