CN103708506A

CN103708506A - Control method of multi-effect evaporation nitrate making process

Info

Publication number: CN103708506A
Application number: CN201310714153.8A
Authority: CN
Inventors: 张春太; 余建兵; 张云照; 何军
Original assignee: SC HONGYA QINGYIJIANG SODIUM SULPHATE CO Ltd
Current assignee: SC HONGYA QINGYIJIANG SODIUM SULPHATE CO Ltd
Priority date: 2013-12-20
Filing date: 2013-12-20
Publication date: 2014-04-09
Anticipated expiration: 2033-12-20
Also published as: CN103708506B

Abstract

The invention discloses a control method of multi-effect evaporation nitrate making process, and belongs to the field of multi-effect evaporation nitrate making processes. The control method adopts a V-effect evaporation system for controlling the solid-to-liquid ratios of various effects one by one, wherein the solid-to-liquid ratios of I, II and III effects are 28-42%, and the solid-to-liquid ratio of IV effect is 8-12%; the flow speed of an I effect circulating pump is 2.07-2.29 m/s. The control method of multi-effect evaporation nitrate making process disclosed by the invention is higher in yield, higher in production efficiency, more energy-saving and environment-friendly and is better in product quality.

Description

The control method of multiple-effect evaporation nitre technique processed

Technical field

The invention belongs to multiple-effect evaporation nitre technology field processed.

Background technology

In traditional technique, multiple-effect evaporation nitre parameter processed is controlled and is in the stage of fumbling, for each effect solid-to-liquid ratio, there is no fixing span of control, each flow velocity of imitating recycle pump lacks scientific appraisal in actual production process, however these two core parameters that parameter is multiple-effect evaporation nitre technique processed.

Summary of the invention

The object of the invention is to: propose a kind of output higher, production efficiency is higher more energy-conserving and environment-protective, and the control method of the better multiple-effect evaporation nitre technique processed of product quality.

The object of the invention realizes by following technical proposals:

A control method for multiple-effect evaporation nitre technique processed, comprises V effect vapo(u)rization system, for each effect solid-to-liquid ratio, by effect, controls, and wherein I, II, III are imitated solid-to-liquid ratio 28%～42%, IV effect solid-to-liquid ratio 8%～12%;

I effect recycle pump flow velocity adopts 1.66m/s～2.48m/s flow velocity.

As selection, I, II, III effect solid-to-liquid ratio are 42%, IV effect solid-to-liquid ratio 12%, and I effect recycle pump flow velocity is 2.29m/s.

As selection, I, II, III effect solid-to-liquid ratio are 35%, IV effect solid-to-liquid ratio 10%, and I effect recycle pump flow velocity is 2.18m/s.

The applicant finds under study for action, the formation of solid-to-liquid ratio to nucleus in tank body, and the growth of crystal plays decisive role, and when solid-to-liquid ratio is lower, in tank body, the degree of supersaturation of feed liquid is low, and the generating rate of nucleus is lower, the growth difficulty of crystal, crystallization effect is poor; And simultaneously, the applicant finds, the recycle pump flow velocity relevant to solid-to-liquid ratio is lower, streams is slow through the speed of heating chamber, and the fouling in heating chamber is serious, causes brush tank frequency higher, average one to two week brush tank once, with short production cycle, recycle pump flow velocity relation, to heating chamber fouling speed degree, becomes the key factor that affects production cycle length.Simultaneously, during brush tank, can cause again a large amount of materials to be arranged outward, the wasting of resources is large, outer row's material causes amount of heat to run off, and steam mono-consumption is high, and not environmental protection is uneconomical, and due to frequent brush tank, cause finished particle degree lower, produce a large amount of II class product after boiling tank simultaneously, the chemical reagent of unavoidably bringing into during not only due to brush tank but also cause the finished product whiteness low production inferior quality.Therefore, in multiple-effect evaporation nitre technique processed, respectively imitating solid-to-liquid ratio control and recycle pump flow velocity is to affect production economy, the important parameter of production cycle length.

Beneficial effect of the present invention: multiple-effect evaporation nitre process parameter control processed method, special process environment for each effect evaporating pot is controlled corresponding solid-to-liquid ratio, and recycle pump is promoted, and has improved the split run output of vapo(u)rization system, effectively prevent heating chamber fouling, extend the production cycle, adopted and concentrate discharging, shortened discharging time, reduced steam mono-consumption, energy-saving and cost-reducing, more economical environmental protection, has reduced production cost:

1) reasonably solid-to-liquid ratio is controlled, and has improved nucleus generating rate and forming rate of crystals, has improved split run output;

2) speed-raising of recycle pump, has effectively prevented heating chamber fouling, has reduced and has boiled tank number of times, with last, by two weeks, brushes tank once, and the system that can guarantee after speed-raising is moved approximately about one month continuously;

3) adopt high solid-liquid ratio operation, concentrate discharging, shorten discharging time, reduced steam mono-consumption, energy-saving and cost-reducing;

4) product quality is improved, and whiteness is higher, and granularity is better.

Embodiment

Following non-limiting examples is used for illustrating the present invention.

One, embodiment

Embodiment 1:

Chart 1-1

Embodiment 2:

Embodiment 3:

Chart 1-3

To sum up:

By above-mentioned to Operational Data Analysis and statistics in multiple-effect evaporation nitre technique processed, known I, II, III effect solid-to-liquid ratio are controlled at IV effect in 28-42 scopes and are controlled in 8-12 scopes, simultaneously suitable raising recycle pump flow velocity, be conducive to improve output, final product quality granularity is large, size distribution is even, and economical operation is reliable.

Comparative example

Comparative example 1:

Comparative example 2: chart 2-1

Chart 2-2

Comparative example 3:

Chart 2-3

Comparative example 4:

To sum up: chart 2-4

In table 2-1, the processing parameter of statistics is known, and when solid-to-liquid ratio lower (when I, II, III effect solid-liquid Bi≤25, Ⅳ Xiao≤8 o'clock), system product quality, output are all not ideal enough, do not belong to best parameter area in multiple-effect evaporation nitre technique processed;

In table 2-2, the processing parameter of statistics is known, when solid-to-liquid ratio lower (when I, II, III are imitated Ⅳ Xiao≤8, solid-liquid Bi≤25), improve separately recycle pump rotating speed, although scale formation makes moderate progress than before, but system product quality, output are all still not ideal enough, do not belong to best parameter area in multiple-effect evaporation nitre technique processed;

In table 2-3, the processing parameter of statistics is known, when solid-to-liquid ratio is too high (when I, II, III effect Ⅳ Xiao≤12, solid-liquid Bi≤45), in vapo(u)rization system, crystalline growth velocity is on a declining curve, heating chamber fouling has the trend of aggravation, does not also belong to best parameter area in multiple-effect evaporation nitre technique processed.

In table 2-4, the processing parameter of statistics is known, and when solid-to-liquid ratio is too high (when I, II, III effect solid-liquid Bi≤45, Ⅳ Xiao≤12 o'clock), in vapo(u)rization system, scaling tendency is alleviated to some extent.But, because crystalline growth velocity in vapo(u)rization system is still on a declining curve, also do not belong to best parameter area in multiple-effect evaporation nitre technique processed.

The foregoing is only preferred embodiment of the present invention, not in order to limit the present invention, all any modifications of doing within the spirit and principles in the present invention, be equal to and replace and improvement etc., within all should being included in protection scope of the present invention.

Claims

1. a control method for multiple-effect evaporation nitre technique processed, comprises V effect vapo(u)rization system, it is characterized in that:

For each effect solid-to-liquid ratio, by effect, control, wherein I, II, III are imitated solid-to-liquid ratio 28%～42%, IV effect solid-to-liquid ratio 8%～12%;

I effect recycle pump flow velocity adopts 2.07m/s～2.29m/s flow velocity.

2. the control method of multiple-effect evaporation as claimed in claim 1 nitre technique processed, is characterized in that: I, II, III effect solid-to-liquid ratio are 42%, IV effect solid-to-liquid ratio 12%, and I effect recycle pump flow velocity is 2.29m/s.

3. the control method of multiple-effect evaporation as claimed in claim 1 nitre technique processed, is characterized in that: I, II, III effect solid-to-liquid ratio are 35%, IV effect solid-to-liquid ratio 10%, and I effect recycle pump flow velocity is 2.18m/s.