CN1629320A - A New Cleaning Technology of Sugar Cane Juice - Google Patents

Abstract

The invention discloses a novel process for cleaning sugar cane juice in sugar production which comprises the steps of, low-temperature phosphor floating treatment, pre-decolorizing with diatomaceous earth and activated charcoal, then loading to boil the sugar. The neutral filtering mud produced in the low-temperature phosphor floating method can be directly used as fertilizer. The process can eliminate the generation of alkaline sieving mud in sugar production.

Description

A New Cleaning Technology of Sugar Cane Juice

technical field

The invention relates to a clean process for producing sugar cane juice from sugarcane, which belongs to the category of clean production process.

technical background

my country's sugarcane sugar industry has long adopted traditional production methods: one is carbonic acid and the other is sulfurous acid. The quality of sugar products produced by the carbonic acid production process is good, but the process is complicated, the cost is high, and the amount of filter mud is large. For every 10,000 tons of sugarcane squeezed, 800 tons of filter mud are produced. The filter mud is strongly alkaline and cannot be used as a fertilizer. Alkaline filter mud has a high content of organic matter (about 11-13%) and cannot be directly used to burn cement. It needs to be stored for more than 5 years before burning cement, so it is necessary to build a large area of storage yard. In addition, secondary pollution is generated during the storage process. At present, there is still no economical and effective way to deal with alkaline filter sludge. In order to remove non-sugar and pigment, milk of lime needs to be added in the production process of carbonation, and carbonation is carried out twice, which leads to lengthening of the process flow. One-third of the investment in sugar factories is for this purpose. The production process of sulfite method is relatively simple, the investment is less, and the filter mud can be used as farmland fertilizer, so most of them adopt this method. But its product quality is not as good as carbonic acid method, and product color value, turbidity, ash content, sulfur content are high, easy to turn yellow, and preservation is poor, increasingly does not meet market demand. Due to the needs of international competition, starting from the 2002/2003 crushing season, the state adjusted the SO ₂ content of white sugar in the product quality standard from 40mg/kg to 30mg/kg, and the requirement was reduced year by year. ₂ The content index should be reduced to below 10mg/kg. It can be seen that the country has more and more strict requirements on the quality of sugar products, and the quality problems of sulfite sugar products directly affect their survival.

At present, China is researching and developing low-temperature phosphorus floatation-carbonic acid clarification process. In this process, before carbonation, low-temperature phosphorus flotation treatment is carried out to remove most of the organic non-sugar content. The purity of the supernatant juice is obviously increased, and the colloid and pigment are greatly reduced, which greatly reduces the burden of clarification treatment. After low-temperature phosphorus flotation, carbonation is carried out, and the amount of ash required is greatly reduced. The process divides the filter mud into two types, one is rich in organic non-sugar and neutral filter mud with nitrogen, phosphorus and potassium fertilizer effects, which can be directly used as fertilizer; the other contains very little organic non-sugar, carbonic acid The alkaline filter mud with a calcium content of more than 85% can be directly fired into cement or used in other industries, and the production of alkaline filter mud is effectively reduced due to the greatly reduced amount of ash added. But this process still has the following main problems: (1) the direct firing of cement with alkaline filter mud is costly and difficult to be accepted by cement manufacturers; ; (3) The process is longer than the traditional carbonation process.

Contents of the invention

The purpose of the present invention is to provide a clean production process for sugarcane juice, that is, the sugarcane mixed juice is first treated with low-temperature phosphorus floatation to remove non-sugar and part of the pigment, and then use diatomite and activated carbon for adsorption Decolorizing agent, to further remove the pigment in the floating clear juice, so that it can meet the requirements of boiling sugar. This process does not produce alkaline filter sludge.

The purpose of the present invention is achieved through the following technical solutions:

A process for cleaning sugarcane juice from sugar cane. The process flow is as follows: the mixed sugar cane juice is first treated with low-temperature phosphorus floatation to remove non-sugar and part of the pigment; The sugar juice adopts gac to further decolorize, and then sends to boil sugar (see process flow chart of the present invention for details).

The technical process provided by the invention is characterized in that:

The new sugarcane juice cleaning process combined with low-temperature phosphorus flotation and floating clear juice adsorption and decolorization avoids the alkaline filter sludge caused by the carbonation method and low-temperature phosphorus flotation-carbonation method, and shortens the process flow.

The low-temperature phosphorous floatation method is used to treat the mixed sugarcane squeezed juice to remove non-sugar and part of the pigment, thereby improving the purity of the sugar juice and reducing its color value.

Diatomaceous earth and activated carbon are used as adsorption decolorizers to further remove the pigment in the floating clear juice to ensure that the processed sugar juice meets the requirements for boiling sugar.

In the diatomite pre-bleaching process, the diatomite is used after roasting at 800° C. for 6 hours, the amount added is 1-3 wt.% of sucrose, the pre-bleaching temperature is 50-75° C., and the pre-bleaching time is 30-60 minutes.

During the decolorization process of the activated carbon, the dosage of the activated carbon is 0.6-1.5wt.% of the sucrose, the decolorization temperature is 50-85°C, and the decolorization time is 15-90min.

Example

For mixed juice with a purity of 78.19AP, preheat to 50°C, add phosphoric acid mixture, neutralize with milk of lime, fill in fine and uniform bubbles, add flocculant, and perform low-temperature phosphorus floatation treatment. The separated neutral filter mud can be directly used as fertilizer or further extracted with high value-added products. The purity of clear juice increased to 80.66AP, and the color value decreased to 92.66°st. Heat the supernatant juice to 75°C, add 1.0wt.% diatomaceous earth relative to the sucrose, pre-decolorize for 60min, and the color value of the juice drops to 75.23°st. Then add 1.0wt.% activated carbon for sugar relative to the sucrose part, continue to decolorize for 30min, and the color value of the juice drops to 30.70 ° st, which can meet the requirements of boiling sugar. This process does not produce alkaline filter sludge.

Claims (3)

1. A new process for cleaning sugarcane juice from sugar cane, characterized in that: sugarcane sugar mixed juice is first treated with low-temperature phosphorus floatation, and the floating clear juice is pre-decolorized with diatomite, then further decolorized with activated carbon, and then sent to Go to boil sugar. This process does not produce alkaline filter sludge. 2. diatomite pre-bleaching process according to claim 1 is characterized in that: diatomite is used after 800 ℃ of roasting 6h, and its add-on is 1-3wt.% of sucrose part, and pre-bleaching temperature is 50- 75°C, the pre-decolorization time is 30-60min. 3. The activated carbon decolorization process according to claim 1, characterized in that: the amount of activated carbon added is 0.6-1.5wt.% of sucrose, the pre-decolorization temperature is 50-85°C, and the decolorization time is 15-90min.