CN1935653A - Method for recovering concentrated ammonia - Google Patents

Abstract

The invention is an ammonia recovering and thickening method, comprising a process of adding in alkali to regulate pH value, evaporating ammonia at low temperature, spraying-absorbing-cooling-circulating, and desorbing the waste liquid by air flow, firstly adding alkali in thiamine solution produced in manganese carbonate production by manganese carbonate waste water to regulate pH to 8-13, water-bathing during blending and controlling temperature at 25DEG C-80DEG C to evaporate ammonia, spraying thin ammonia solution to circularly absorb the evaporated ammonia, cooling while absorbing,controlling temperature at 0DEG C-35DEG C,controlling vacuum at 600-650mmhg, and, when the absorbed ammonia solution reaches 15% above, and the ammonia content in the residual solution is less than 0.15%, stopping ammonia evaporation, blow- desorbing the residual solution by air at normal temperature until the ammonia content is less than 15ppm and pH value is less than 9, reaching the effluent standard. And it can recover and thicken ammonia from thiamine solution, reducing energy comsuption and putting an end to environmental pollution caused by thiamine discharge.

Description

A kind of method that reclaims concentrated ammonia

Technical field

The present invention relates to a kind of recovery technology of ammonia, particularly a kind of from produce the method that reclaims concentrated ammonia the waste water ammonium sulfate solution that produces behind the manganous carbonate with manganous sulfate waste water.

Background technology

The method that reclaims ammonia in the ammonia nitrogen waste water is more, high-temperature steam stripping commonly, the treatment process that the absorption tower circulation absorbs.This method steam consumption height, investment cost is higher, and the absorption tower column plate is perishable, and processing costs is higher.

Summary of the invention

Purpose of the present invention is exactly that a kind of method that reclaims concentrated ammonia will be provided, it comprises that adding alkali transfers pH value, low temperature ammonia still process, sprays refrigeration cycle, the waste liquid air stripping process of absorbing, energy is alleviated present from the production pressure with the waste water ammonium sulfate solution that produces behind the manganous sulfate waste water production manganous carbonate, and has solved the problem of environmental pollution and material waste.

The object of the present invention is achieved like this: a kind of method that reclaims concentrated ammonia, it comprises that adding alkali transfers pH value, low temperature ammonia still process, sprays refrigeration cycle and the waste liquid air stripping process of absorbing.Concrete steps are:

A, add alkali and transfer pH value: will add alkali accent PH to 8～13 from produce the waste water ammonium sulfate solution that produces behind the manganous carbonate with manganous sulfate waste water earlier;

B, low temperature ammonia still process: 25 ℃～80 ℃ ammonia that will volatilize of water-bath temperature control steam under the agitation condition, and water absorbs into dilute ammonia solution;

C, injection absorb refrigeration cycle: absorb volatilization ammonia with the dilute ammonia solution spraying cycle, limit ABSORPTION EDGE cooling, controlled temperature is at 0 ℃～35 ℃, and vacuum degree control is at 600～750mmhg, the ammonia soln that absorbs finally reaches 15%～18%, and ammonia content is less than 0.15% in the raffinate;

D, waste liquid air stripping: ammonia-nitrogen content is less than 15ppm to the liquid effluent through the normal temperature air stripping for raffinate, and PH is less than 9, discharging.

Adopt the inventive method, can from ammonium sulfate solution, reclaim ammonia and enrichment, to produce the ammonium sulfate solution (average quality mark about 14%) of 1000g, can reclaim the about 35.8g of ammonia wherein, but compare conserve energy consumption with traditional technology, stopped the sulphur ammonium and efflux the environmental pollution that causes, the production cost that has reduced has improved economic benefit.

Description of drawings

Embodiment is further described the present invention below in conjunction with accompanying drawing;

Fig. 1 is a process flow diagram of the present invention;

Fig. 1 double as Figure of abstract.

Embodiment

As shown in Figure 1, quantitatively will be added in the reactor from producing the amine wastewater of sulphuric acid that produces behind the manganous carbonate with manganous sulfate waste water, add alkali and transfer its PH to 8～13, under the agitation condition, 25 ℃～80 ℃ low temperature ammonia still processs of water-bath temperature control, absorb the volatilization ammonia that steams with the dilute ammonia solution spraying cycle, limit ABSORPTION EDGE cooling, controlled temperature is at 0 ℃～35 ℃, and vacuum degree control is at 600～750mmhg, the ammonia soln that absorbs finally reaches 15%～18%, and ammonia content is less than 0.15% in the raffinate; Ammonia-nitrogen content is less than 15ppm to the liquid effluent through the normal temperature air stripping for raffinate in the reactor, and PH is less than 9, discharging.

Ammonium sulfate solution with 300ml is that example illustrates technological process of the present invention below.

Embodiment one:

The ammonium sulfate solution of 300ml is added in the round mouth flask of 500ml, slowly add alkali and transfer its PH to 11,45 ℃ of low temperature ammonia still processs of water-bath temperature control under the agitation condition are drenched dilute ammonia solution down through injector with the small-sized liquid pump of beating, control vacuum tightness 650mmhg, limit ABSORPTION EDGE water temperature control to 25 ℃.After circulation absorbed 60min, the ammonia soln of absorption finally reached more than 15%, ammonia content about 0.15% in the raffinate in the flask.Ammonia-nitrogen content is less than 15ppm to the liquid effluent through the normal temperature air stripping for raffinate in the flask, and PH reaches emission standard less than 9, discharging.

Embodiment two:

The ammonium sulfate solution of 300ml is added in the round mouth flask of 500ml, slowly add alkali and transfer its PH to 12,50 ℃ of low temperature ammonia still processs of water-bath temperature control under the agitation condition are drenched dilute ammonia solution or clear water down through injector with the small-sized liquid pump of beating, control vacuum tightness 620mmhg, limit ABSORPTION EDGE water temperature control to 30 ℃.After circulation absorbed 90min, the ammonia soln of absorption finally reached more than 15%, ammonia content about 0.15% in the raffinate in the flask.Ammonia-nitrogen content is less than 15ppm to the liquid effluent through the normal temperature air stripping for raffinate in the flask, and PH reaches emission standard less than 9, discharging.

Embodiment three:

The ammonium sulfate solution of 300ml is added in the round mouth flask of 500ml, slowly add alkali and transfer its PH to 8,25 ℃ of low temperature ammonia still processs of water-bath temperature control under the agitation condition are drenched dilute ammonia solution down through injector with the small-sized liquid pump of beating, control vacuum tightness 600mmhg, limit ABSORPTION EDGE water temperature control to 0 ℃.After circulation absorbed 60min, the ammonia soln of absorption finally reached more than 17%, ammonia content about 0.15% in the raffinate in the flask.Ammonia-nitrogen content is less than 15ppm to the liquid effluent through the normal temperature air stripping for raffinate in the flask, and PH reaches emission standard less than 9, discharging.

Embodiment four:

The ammonium sulfate solution of 300ml is added in the round mouth flask of 500ml, slowly add alkali and transfer its PH to 13,80 ℃ of low temperature ammonia still processs of water-bath temperature control under the agitation condition are drenched dilute ammonia solution down through injector with the small-sized liquid pump of beating, control vacuum tightness 750mmhg, limit ABSORPTION EDGE water temperature control to 35 ℃.After circulation absorbed 60min, the ammonia soln of absorption finally reached more than 18%, ammonia content about 0.15% in the raffinate in the flask.Ammonia-nitrogen content is less than 15ppm to the liquid effluent through the normal temperature air stripping for raffinate in the flask, and PH reaches emission standard less than 9, discharging.

Claims (1)

1, a kind of method that reclaims concentrated ammonia, it comprises that adding alkali transfers pH value, low temperature ammonia still process, sprays absorption refrigeration cycle and waste liquid air stripping process, is characterized in that step is:

A, add alkali and transfer pH value: will add alkali accent PH to 8～13 from produce the waste water ammonium sulfate solution that produces behind the manganous carbonate with manganous sulfate waste water earlier;

B, low temperature ammonia still process: 25 ℃～80 ℃ ammonia that will volatilize of water-bath temperature control steam under the agitation condition, and water absorbs into dilute ammonia solution;

C, injection absorb refrigeration cycle: absorb volatilization ammonia with the dilute ammonia solution spraying cycle, limit ABSORPTION EDGE cooling, controlled temperature is at 0 ℃～35 ℃, and vacuum degree control is at 600～750mmhg, the ammonia soln that absorbs finally reaches 15%～18%, and ammonia content is less than 0.15% in the raffinate;

D, waste liquid air stripping: ammonia-nitrogen content is less than 15ppm to the liquid effluent through the normal temperature air stripping for raffinate, and PH is less than 9, discharging.

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