WO2016183947A1

WO2016183947A1 - Deep treatment method for polluted wastewater containing thallium and other heavy metal

Info

Publication number: WO2016183947A1
Application number: PCT/CN2015/086635
Authority: WO
Inventors: 韩正昌; 高亚娟; 马军军; 崔洪磊; 韩思宇
Original assignee: 南京格洛特环境工程股份有限公司
Priority date: 2015-05-20
Filing date: 2015-08-11
Publication date: 2016-11-24
Also published as: CN104925988A

Abstract

A deep treatment method for polluted wastewater containing thallium and other heavy metal, consisting of three steps of acidic catalytic reduction, thallium-removing agent precipitation, and filtration. The concentration of thallium can be reduced to less than 5 μg/L. A thallium-removing agent mainly consists of the following substances in parts by weight: 10 to 99 parts of sulfide, 0.1 to 20 parts of calcium chloride, 0.1 to 10 parts of magnesium oxide, 0.1 to 10 parts of calcium oxide, 0.1 to 10 parts of activated carbon, 0.2 to 10 parts of diatomaceous earth, 0.2 to 10 parts of attapulgite, 0.1 to 10 parts of PAM, and 0.1 to 10 parts of PAC.

Description

Advanced treatment method for heavy metal contaminated wastewater containing cesium and the like

[0001] The present invention belongs to the technical field of wastewater treatment, and particularly relates to the field of advanced treatment of heavy metal-contaminated wastewater containing antimony such as steel, lead, zinc and copper, and particularly relates to an advanced treatment method for heavy metal wastewater containing hydrazine.

Background technique

[0002] 铊 (T1) is a typical rare dispersing element. Strontium and its compounds are highly toxic, much more toxic than arsenic oxide, and have obvious effects on the gastrointestinal tract and kidneys. Toxicity is far greater than Hg, Pb, As and other elements. Antimony compounds are one of the major hazardous wastes listed in the World Health Organization's list of priority restrictions. They are also listed as priority pollutants in China. In October 2010, the phenomenon of over-standards was found in the middle and upper reaches of the Beijiang River in Shaoguan City. According to the environmental protection department, the over-standard was caused by the sewage from the Shaoguan smelter in the south of Zhongjinling. According to the requirements of the provincial government, the Shaoguan smelter has been completely shut down, which almost means that the stagnation of lead and zinc smelting in Zhongjin Lingnan will directly reduce the company's net profit by about 27 million yuan per one month of production suspension.

[0003] The lanthanum element has a philophilic and bisophilic duality. As a lithophile element, it is found in mica, potassium feldspar, manganese minerals, alum, and jarosite. As a sulphur-rich element, strontium is mainly found in the form of trace elements in galena, pyrite, sphalerite, chalcopyrite, pyrite and pyrite. Weathered leaching with antimony ore, smelting waste, non-ferrous, metallurgical, chemical, mining and industrial wastewater discharge and soot deposition in coal-fired power plants are all ways to enter the environmental water body.

[0004] The world produces less than 15 tons of cockroaches per year, and about 2,000 to 5,000 tons of cockroaches are emitted each year. This brings about a series of environmental pollutions such as soil sputum pollution, water pollution, and chronic poisoning of humans and animals. problem.

[0005] The environmental pollution problems caused by 铊 are not as common as those of As, Cd, Pb, Hg, etc. Therefore, 铊 has not been included in the monitoring scope of environmental protection departments at all levels, especially in China, soil, water, gas and other pollution research and various related Environmental impact assessment documents are often excluded from the analysis of research objects, resulting in industry standards such as "lead and zinc industrial pollutant discharge standards", "steel industry water pollutant discharge standards", "copper, nickel, cobalt industrial pollution Emission standards, etc., to the national standard "Sewage Integrated Emission Standards" and other series of pollution The lack of indicators for the discharge of dyes. Hunan Province has established a local standard for the emission of antimony, which stipulates that the wastewater discharge standard for radon is 5 g/L. On May 4, 2015, the State issued the “Inorganic Chemical Industry Pollutant Emission Standard” (GB31573-2015), which stipulated that the pollution emission limit of 铊 was 5 g/L, which was implemented on July 1, 2015. Since then, cesium pollution has had corresponding emission standards.

[0006] With China's emphasis on the ecological environment and the deep understanding of pollution in the industry, research on the treatment of wastewater containing strontium has begun.

technical problem

At present, methods commonly used in the prior art are mainly chemical precipitation methods, adsorption methods, membrane methods, biological methods, and the like.

Since the adsorption method can only treat wastewater less than 铊 content 1 (Vg/L or less), its application is limited, and the adsorption process requires porous materials or ion exchange materials, so the cost is relatively high, and it is not suitable for industrial wastewater treatment. The hydrazine adsorbent is still a hazardous waste after adsorption, and the treatment problem still needs to be solved. Therefore, the adsorption method is not adopted by most enterprises.

[0008] Similarly, membrane methods and biological methods cannot be promoted by a wide range of industries due to their removal effects and the applicability of raw materials.

[0009] Now, we have studied more chemical precipitation methods, which mainly involve three types, one is alkali precipitation, one is sulfide precipitation, and the other is chlorination precipitation, but these three The treatment method can not only reduce the concentration of strontium to 10 (Vg / L, can not meet the deep treatment, and then reach the 5 g / L emission requirements. Problem solution

Technical solution

[0010] In order to meet the latest emission standards, the present invention discloses an advanced treatment method for wastewater containing heavy metals such as helium, by which the concentration of rhodium can be reduced to less than 5 g/L to meet emission standards.

[0011] In order to achieve this, the advanced treatment method of the present invention is by acid reduction, deuterium deposition

And filtering three steps, the reaction can be expressed as

[0012] (1) Tl ³⁺ +2e-→Tl+,

[0013] (2) ηΤ1 ÷+Μ «→Τ1 _η Μ, Μ represents a non-metallic anion,

[0014] wherein the reaction ρ Η condition of the step (1) is 1 to 6.

[0015] The inventive method reduces the T1 3+ to Tl + under the acidic reducing condition, and further forms a precipitate, and uses the precipitate

The filtration process removes the cerium-containing precipitate and removes the strontium element from the wastewater. After an advanced treatment method, the concentration of cerium in the wastewater is less than 5 g/L. Similarly, the present invention does not require additional steps, and can complete the mercury and lead precipitation in the one-step reaction precipitation. After treatment, the mercury concentration in the wastewater is less than 5 g. /L

The lead concentration is less than 0.5mg/L.

[0016] In actual operation, we can use hydrochloric acid, citric acid, etc. as a pH adjuster to adjust the pH of the wastewater.

[0017] In the present invention, it relates to the acidic reduction of trivalent europium ions, in which we can use reducing gases for reduction, such as hydrogen, carbon monoxide, hydrogen sulfide; reducing metals and their compounds and/or Reduction of a reducing catalyst formed by a reducing non-metal and its compound.

[0018] Further, we have given a preferred herbicide, mainly composed of the following parts by weight

, 10-99 parts of sulfide, 0.1_20 parts of calcium chloride, 0.1_10 parts of magnesium oxide, 0.1_10 parts of calcium oxide, 0.1 to 10 parts of activated carbon, 0.2-10 parts of diatomaceous earth, 0.2-10 parts of attapulgite, 0.1 — 10 copies of PAM, 0.1-1

0 parts PAC.

Advantageous effects of the invention

Beneficial effect

[0019] Compared with the technical solutions disclosed in the prior art, the present invention has the following beneficial effects:

[0020] 1. There is no requirement for the concentration of strontium element in the wastewater to be treated, and the discharge amount of the treated effluent reaches 5 g/L can be ensured by adjusting the addition amount of the reducing agent and the herbicide removing agent.

[0021] 2. The process flow is simple, easy to operate and manage. The herbicidal removal process of the present invention mainly includes two processes

First, the catalytic reduction pretreatment process, the first is the process of removing the sedimentation process, the process is simple and easy to learn, easy to operate and manage.

[0022] 3. The equipment investment cost is low. The deuterium removal process disclosed in the present invention only involves several steps of catalytic reduction, precipitation and filtration, so that the original wastewater treatment process structure and equipment can be modified and optimized without dismantling the original equipment. At the same time, these steps are very easy to integrate, so the reaction equipment occupies a small area, is highly automated, and is neat and tidy.

[0023] 4. Since the advanced treatment process disclosed in the present invention does not require expensive materials and chemicals, the operating cost is low. After preliminary calculation, the cost of treating one ton of wastewater with different cerium and mercury concentration-contaminated wastewater by the advanced treatment method of the present invention can be controlled between 0.6 and 5.0 yuan.

Brief description of the drawing

DRAWINGS [0024] The description paragraphs are entered here by way of a drawing.

BEST MODE FOR CARRYING OUT THE INVENTION

[0025] Preferably, the reaction p H condition in the step (1) is 2 to 4.

[0026] Preferably, we provide a combination of reducing catalytic materials, the catalytic still filler is composed of the following parts by weight, 5-99.5 parts of iron-containing mixed substance iron-containing mixture, 0.1-30 parts The reducing metal element, 0.1-15 parts of the reducing carbonaceous material, 0.1-20 parts of the reducing sulfur-containing substance, 0.1-15 parts of the reducing zinc-containing substance, and 0.1-15 parts of the reducing nitrogen-containing substance.

[0027] In the same way, we further give the use of a reducing gas in the acid reduction process, the amount of which is 1 to 100 m3 per ton of wastewater, or when a catalytic reduction filler is used. The amount added is 50~200kg per ton of wastewater.

Embodiments of the invention

[0028] In order to better understand the present invention, the present invention will be further described below in conjunction with the specific embodiments.

Example 1 Preparation of Catalytic Reduction Agent

[0030] according to 5 parts of the iron-containing mixture, 0.1 part of the reducing metal element, 0.1 part of the reducing carbonaceous material, 0.1 part of the reducing sulfur-containing substance, 0.1 part of the reducing zinc-containing substance, 0.1 part of the reducing nitrogen-containing substance Mixing to form a reducing catalyst.

[0031] according to 99.5 parts of iron-containing mixture, 30 parts of reducing metal element, 15 parts of reducing carbonaceous material, 20 parts of reducing sulfur-containing substance, 15 parts of reducing zinc-containing substance, 15 parts of reducing nitrogen-containing substance Mixing to form a reducing catalyst.

[0032] According to 50 parts of iron-containing mixture, 15 parts of reducing metal element, 7 parts of reducing carbonaceous material, 10 parts of reducing sulfur-containing substance, 7 parts of reducing zinc-containing substance, and 7 parts of reducing nitrogen-containing substance Mixing to form a reducing catalyst.

Example 2 Preparation of Herbicide Removal Agent

[0034] according to 10 parts of sulfide, 0.1 parts of calcium chloride, 0.1 parts of magnesium oxide, 0.1 parts of calcium oxide, 0.1 parts of activated carbon, 0.2 parts of diatomaceous earth, 0.2 parts of attapulgite, 0.1 parts of PAM, 0.1 parts of PAC The above materials were mixed and further ground to form a mixed powder having a particle diameter of less than 20 mesh. [0035] according to 99 parts of sulfide, 20 parts of calcium chloride, 10 parts of magnesium oxide, 10 parts of calcium oxide, 0.1-10 parts of activated carbon, 0.2-10 parts of diatomaceous earth, 0.2-10 parts of attapulgite, 0.1_10 parts The above materials were mixed by PAM, 0.1 to 10 parts of PAC, and further ground to form a mixed powder having a particle diameter of less than 20 mesh.

[0036] according to 50 parts of sulfide, 10 parts of calcium chloride, 5 parts of magnesium oxide, 5 parts of calcium oxide, 5 parts of activated carbon, 5 parts of diatomaceous earth, 5 parts of attapulgite, 5 parts of PAM, 5 parts of PAC The above materials were mixed and further ground to form a mixed powder having a particle diameter of less than 20 mesh.

Example 3

[0038] detecting the content of heavy metal ions in the industrial wastewater containing heavy metals such as cerium, wherein the cerium element content is 1745 (Vg/L, the mercury element content is 20.03 g/L, and the lead element content is 8.77 g). /L. Take 1 000ml of industrial wastewater, adjust the pH of the wastewater to 2 with hydrochloric acid, add any reducing catalytic agent configured in Example 1, add 20g / L, stir for 60 minutes, suction filtration, into solution Add any of the herbicides prepared in Example 2, stir for 60 minutes, and filter by suction to remove the precipitate. The wastewater to be discharged is subjected to water sample quality test by ICP-MS, and the content of barium in the water is determined to be 2.04 g/ L, the content of mercury is 2.76 g / L, and the content of lead is 4.43 g / L.

Example 4

[0040] detecting the heavy metal ion content in the industrial wastewater containing heavy metals such as cerium, wherein the cerium element content is 5837 g/L, the mercury element content is 0.45 g/L, and the lead element content is 1901 g/ L, measure 100 0ml of industrial wastewater, adjust the pH of the wastewater to 4 with hydrochloric acid, pass the reducing gas hydrogen sulfide, the gas flow rate is 15 m 3 / h, stir for 60 minutes, suction filtration, add the configuration in Example 2 to the solution. A good herbicide, stir for 60 minutes, filter by suction, and remove the precipitate. The wastewater to be treated is tested by ICP-MS for the water quality of the water sample. The content of barium in the water is 2.67 g/L, the content of mercury is 0.38 g/L, and the content of lead is 0.7.

[0041] The invention reduces the T1 3+ to Tl + under the acidic reducing condition, and further forms a precipitate, and removes the cerium-containing precipitate by a precipitation and filtration process, and removes the strontium element in the wastewater, and passes the test. After this advanced treatment, the concentration of strontium in the wastewater is less than 5 g/L, and no additional steps are required. Mercury and lead precipitation can be completed in the one-step reaction precipitation. After treatment, the mercury concentration in the wastewater is less than 5 g/L, lead. The concentration is less than 0.5 mg/L. In engineering applications, only catalytic pretreatment equipment, radon removal equipment and solid-liquid separation equipment are required. The operation process is simple, the treatment effect is stable, the engineering has strong useability, and has broad market prospects. Sequence table free content

Type the sequence table free content description paragraph here.

Claims

Claims an advanced treatment method for wastewater containing heavy metals such as thallium, which is characterized by consisting of three steps: catalytic reduction, thallium removal agent precipitation, and filtration. The reaction can be expressed as,

(1) Tl ³⁺ +2e→Τ1 +,

(2) ηΤ1 ⁺ +Μ ^η →Τ1 _η Μ, Μ. - represents a non-metal anion,

The reaction PH conditions of step (1) are 1 to 6.

The advanced treatment method for wastewater containing heavy metals such as thallium according to claim 1, characterized in that the reaction PH conditions of step (1) are 2 to 4.

The advanced treatment method for wastewater containing heavy metals such as thallium according to claim 1, characterized in that, during the acidic catalysis process, reducing solids and/or reducing gases are used for reduction.

The advanced treatment method for wastewater containing heavy metals such as thallium according to claim 3, characterized in that the reducing solid is a catalytic reduction filler formed by mixing reducing metals and their compounds and/or reducing non-metals and their compounds.

The advanced treatment method for wastewater containing heavy metals such as thallium according to claim 3, characterized by:

, the reducing gas is hydrogen, carbon monoxide, and hydrogen sulfide.

The advanced treatment method for wastewater containing heavy metals such as thallium according to claim 3 or 5, characterized in that the amount of reducing gas introduced is 1 to 100m3 per ton of wastewater.

The advanced treatment method for wastewater containing heavy metals such as thallium according to claim 3 or 4, wherein the adding amount of the reducing solid is 50 to 200kg per ton of wastewater.

The advanced treatment method for wastewater containing heavy metals such as thallium according to claim 1, characterized by:

, the thallium removal agent is mainly composed of the following parts by weight: 10-99 parts of sulfide, 0.

1_20 parts calcium chloride, 0.1_10 parts magnesium oxide, 0.1_10 parts calcium oxide, 0.1_10 parts activated carbon, 0.2-10 parts diatomite, 0.2-10 parts attapulgite, 0.1-10 parts PAM, 0.1-10 parts PAC .

The advanced treatment method for wastewater containing heavy metals such as thallium according to claim 4, characterized in that the catalytic reduction filler is composed of the following parts by weight, 5-99.5 parts of iron-containing mixture, 0.1-30 parts of reducing metals Elemental substance, 0.1-15 parts of reducing carbonaceous substances, 0.1-20 parts of reducing sulfur-containing substances, 0.1_15 parts of reducing zinc-containing substances, 0.1_15 parts of reducing substances Nitrogenous substances.