JPH0460718B2 - - Google Patents
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- Publication number
- JPH0460718B2 JPH0460718B2 JP59060345A JP6034584A JPH0460718B2 JP H0460718 B2 JPH0460718 B2 JP H0460718B2 JP 59060345 A JP59060345 A JP 59060345A JP 6034584 A JP6034584 A JP 6034584A JP H0460718 B2 JPH0460718 B2 JP H0460718B2
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- pickling
- sludge
- waste liquid
- stainless steel
- neutralizing agent
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Description
【発明の詳細な説明】
この発明は、ステンレス鋼の酸洗工程で排出さ
れる酸洗廃液の中和剤の消費量少なく中和すると
同時に、処理液形態を過脱水機の負荷が軽減さ
れる形態となす、ステンレス鋼酸洗廃液の処理方
法に関するものである。
一般に、ステンレス鋼の冷間圧延や、鍛造又は
熱処理等によつて得られたステンレス鋼製品の仕
上げの際には、ステンレス鋼表面に生成している
酸化スケールを除去するための酸洗工程が必須と
されており、このようなステンレス鋼の酸洗に
は、通常、硝酸：10〜20重量％、弗酸：２〜４重
量％程度を混合した混酸水溶液が使用されてい
る。
ところで、このような酸洗液は、当然のことな
がら酸洗が進むにつれ酸洗能力が劣化し、処理能
力が次第に低下して来るので、劣化した酸洗液は
“酸洗廃液”として廃液処理施設に移された後中
和処理され、廃棄されていた。
なお、ステンレス鋼の酸洗液の劣化度を管理す
る方法としては、
酸洗後の組成を適宜分析し、上述したような
組成範囲内に維持する方法、
酸洗液中の鉄分量を測定し、その量が特定値
を越えないように管理する方法、
等が実施されており、酸洗液組成や液中鉄分量が
許容量から外れた場合に該酸洗液が劣化したと判
断されている。
そして、従来、劣化したステンレス鋼酸洗廃液
は、第１図に示されるような工程で処理されるの
が普通であつた。
即ち、排出された酸洗廃液（通常、硝酸：10重
量％、弗酸：２重量％、溶解鉄：４重量％、溶解
クロム：１重量％、固形物：0.06重量％程度を含
む水性液である）は、酸洗後の処理材を洗浄する
際に多量に排出される酸洗洗浄廃水（通常、硝
酸：0.05重量％、弗酸：0.001重量％、溶解鉄：
0.03重量％、溶解クロム：0.01重量％、固形物：
0.02重量％程度を含む）中に該酸洗洗浄廃水：
120m3当り0.5〜1.0m3程度の少量ずつ投入されて、
酸洗廃液中に高い濃度で溶解しているステンレス
鋼酸化スケールの主成分たるFe，Cr等の金属、
或いはNO- 3，F-等の酸基が希釈された状態とさ
れた後に、中和槽１で水酸化カルシウム：５重量
％程度を含有する中和剤（カーバイド滓等）でPH
９〜10に中和処理される。この処理によつて、廃
液中に溶解している金属類はFe（OH）3やCr（OH）
3等の水酸化物となり、また酸基類はCa（NO3）2
やCaF等の化合物となり、無害化されるのであ
る。
次いで、このように処理された廃液は、調整槽
２を経て凝集槽３へ送られるが、この凝集槽３に
おいて、懸濁している前記化合物を粗大化すると
ともに沈降性を高めるべく凝集剤が添加される。
続いて、該廃液は固液分離槽４に移され、約８時
間前後の滞留時間にて固液分離される。
固液分離により分離された上澄水（「処理水」
と称される）は最終PH調整処理された後放流され
るが、一方、固形物（「スラリー」と称される）
は、水分を多く含んでいるため熟成槽５、調整槽
６を経て濃縮槽（シツクナー）７に導かれ、約８
時間前後の滞留時間を持たせることによつて泥状
とされた後、過脱水機（例えばオリバー式真空
過機等）８で脱水され、スラツジとされる。
以上が、従来行われていたステンレス鋼酸洗廃
液の処理工程であるが、近年、酸洗処理量の増大
に比例して酸洗廃液排出量が著しく多くなつたこ
ともあつて、これまでの廃液処理法には次に示す
(a)〜(c)項の如き問題点のあることが明らかとなつ
てきたのである。即ち、
(a) 従来、酸洗廃液の中和処理は常温で実施され
ているが、酸洗廃液中に投入されている中和剤
の主成分（必要成分）である水酸化カルシウム
は常温での溶解度が極めて小さくて反応効率が
低いので、歩留りが悪く、従つて中和剤の消費
量が多くなる、
(b) 第１図にも示されるように、酸洗廃液の処理
に多くの工程が必要であり、従つて処理時間が
長くなる上、処理能率も悪い、
(c) 副産物として多量の汚泥が発生するので汚泥
処理が必要となる上、汚泥の濃縮度合が低いた
めに過機（脱水機）での脱水効率も悪く、例
えばオリーバー式真空過機で脱水したスラツ
ジ中の水分含有量は75〜78重量％と高くなつて
スラツジ発生量の増大を招くばかりか、過機
の過負荷の原因となる。
本発明者等は、上述のような観点から、ステン
レス鋼酸洗廃液を出来るだけ少ない工程で能率良
く処理できるとともに、中和剤の消費量や、過
機（脱水機）の負荷増大を招く汚泥の発生量をも
極力抑え得る廃液処理方法を見出すべく、試行錯
誤を繰り返しながら鋭意研究を重ねた結果、以下
○イ〜○ハに示されるような知見が得られたのであ
る。
○イ ステンレス鋼の酸洗廃液を、酸洗洗浄廃水で
希釈することなくそのまま高濃度中和剤（水酸
化カルシウム含有量の高い中和剤）で処理する
と、その際の中和反応熱によつて酸洗廃液の温
度が50〜60℃程度にまで上昇し、この比較的高
い液温のため、廃液成分と中和剤中の水酸化カ
ルシウムとの反応速度や反応率が著しく高くな
つて、少ない中和剤消費量によつて十分な中和
処理が可能となる上、生成する汚泥の凝集性、
沈降性、含水量とも脱水処理に極めて都合の良
いものとなり、しかも汚泥発生量そのものが格
段に少なくなること。
即ち、第２図はステンレス鋼酸洗廃液そのも
のと、これを酸洗洗浄廃水で希釈したもの
（120倍に希釈）について、PH9.0の中和値まで
中和剤（カーバイド滓）を添加した際の中和剤
濃度（中和剤中の水酸化カルシウム濃度）と反
応熱による処理液到達温度との関係を比較した
グラフであり、第３図は中和剤濃度と中和剤消
費量（処理液１当りに必要な水酸化カルシウ
ムの量）との関係を、酸洗廃液のみ、酸洗廃液
を酸洗洗浄廃水で希釈したもの、及び酸洗洗浄
廃水について示したグラフであるが、第２図及
び第３図からも、酸洗廃液単独のものに水酸化
カルシウム含有量：20重量％以上の高濃度中和
剤を添加して中和処理すると液温が高くなり、
しかも中和処理に要する中和剤の消費量が少な
くなることがわかる。
また、第４図は中和処理後の汚泥の沈降性を
示したグラフであり、試験液を直径：150mmの
ガラスシリンダーに入れて５分間攪拌後静置
し、経過時間と凝集高さ（水と分離沈降した汚
泥の沈積高さ）を測定して沈降性を求めたもの
である。
更に、第５図は、処理対象液をその種類別に
ガラスシリンダー（直径：150mm）に入れ、１
時間放置後に測定した汚泥高さでもつて表わし
たところの生成汚泥量を比較したグラフ、第６
図は上澄液を取り除いた汚泥中の固形物濃度を
比較したグラフであつて、一定量の汚泥を110
℃にて２時間乾燥して測定したものである。
そして、第７図はオリバー式真空過機にて
真空度：40Kg／m2で脱水した汚泥の含水率を各
処理液毎に比較したグラフである。
このように、第４乃至第７図で示される結果
からも、ステンレス鋼酸洗廃液を希釈すること
なくそのまま中和処理した方が、汚泥発生量も
少なく、しかも固液分離作業の容易であること
が明らかである。
○ロ しかしがなら、ステンレス鋼酸洗廃液を希釈
することなくそのまま中和処理すると、公害規
制法の適用外ではあるが、中和処理後の処理水
に異常な茶褐色の変色が生じ、そのまま放流す
るには不適当なものとなること、
○ハ ところが、思いがけなくも、異常変色した上
記処理水を10〜12％以下程度の割合で酸洗洗浄
廃水に混入すると、変色が無くなつて透明とな
るので、格別に面倒な処理を要しない酸洗洗浄
廃単独の処理系統で一緒に処理ができるように
なること。なお、前記異常変色は、廃酸中に含
まれるMx（NO2）ｙやMx（NO3）ｙ等の不純
物含有量が或る範囲を越えた場合に発生するも
のであり、これが酸洗洗浄廃水中に混入される
と、逆中和によつて色が消失するものと考えら
れる。
この発明は、上記知見に基づいてなされたもの
であつて、ステンレス鋼酸洗廃液を、
(a) 中和槽で、上記ステンレス鋼酸洗廃液に、該
酸洗廃液を希釈することなく、水酸化カルシウ
ム含有量：20重量％以上の高濃度中和剤を添加
して中和処理し、
(b) ついで、中和処理後の汚泥を、調整槽を経て
直接濃縮槽に送り、
(c) 上記濃縮槽での上澄液である変色処理水は酸
洗洗浄廃水に混入して、酸洗洗浄廃水単独の処
理系統で一緒に処理し、一方同濃縮槽での汚泥
は炉過脱水機にてスラツジとする、
以上(a)〜(c)の工程により処理することにより、
中和剤の消費量や汚泥の発生量少なく、かつ高能
率で、ステンレス鋼酸洗廃液を処理する方法に特
徴を有するものである。
なお、前記「中和剤」として、有効成分として
水酸化カルシウムを含有するところの、通常この
種の中和処理に使用されているものであればいず
れもを採用することができ、水酸化カルシウム単
独であつても適用可能であることはもちろんであ
るが、コスト面を考慮すればカーバイト滓を用い
るのが好ましい。
また、中和剤中の水酸化カルシウム含有量を20
重量％以上と限定したのは、第２図及び第３図か
らも明らかなように、中和剤中の水酸化カルシウ
ム含有量が20重量％以上になると中和反応熱発生
量が急増して中和反応効率を高め、中和剤が無駄
なく反応するからであり、中和剤中の水酸化カル
シウム含有量が20重量％未満では前記効果が十分
でない。なお、該水酸化カルシウム含有量は20〜
25重量％とすることが好ましいことも、第２図及
び第３図から明白である。
そして、この発明の方法を採用すると、中和剤
で中和処理された後の廃液中の汚泥は凝集性・沈
降性が極めて良好で、かつ含水率が低いため、第
８図で示される如き簡単な工程にてその後の処理
が可能となり、しかも汚泥発生量が激減するので
ある。
次に、実操業によつてステンレス鋼酸洗廃液を
処理した結果について、従来法と本発明方法とを
比較して示す。
従来法は、第１図に示されるような処理工程に
て、通常のステンレス鋼酸洗廃液を酸洗洗浄廃水
に少量ずつ（酸洗洗浄廃水：120m3当り0.5〜1.0
m3の割合）投入して希釈し、水酸化カルシウムを
５重量％の割合で含有するカーバイト滓から成る
中和剤にてPH９〜10に中和処理することで実施し
た。一方、本発明方法は第８図に示されるような
処理工程にて、ステンレス鋼酸洗廃液に水酸化カ
ルシウム含有量：25％のカーバイト滓を直接投入
してPH９〜10に中和処理することで実施した。
このような試験によつて、
○
[Detailed Description of the Invention] This invention reduces the consumption of neutralizing agent in the pickling waste liquid discharged in the pickling process of stainless steel, and at the same time reduces the load on the super-dehydrator by changing the form of the treated liquid. The present invention relates to a method for treating stainless steel pickling waste liquid. Generally, when finishing stainless steel products obtained by cold rolling, forging, or heat treatment of stainless steel, a pickling process is required to remove oxidized scale that has formed on the surface of the stainless steel. For pickling stainless steel, a mixed acid aqueous solution containing approximately 10 to 20% by weight of nitric acid and 2 to 4% by weight of hydrofluoric acid is usually used. By the way, as the pickling process progresses, the pickling ability of such a pickling liquid naturally deteriorates and the processing capacity gradually decreases, so the deteriorated pickling liquid is treated as waste liquid as "pickling waste liquid". After being transferred to a facility, it was neutralized and disposed of. In addition, methods for controlling the degree of deterioration of stainless steel pickling solution include methods such as appropriately analyzing the composition after pickling and maintaining the composition within the above-mentioned range, and measuring the iron content in the pickling solution. , a method to control the amount so that it does not exceed a specific value, etc. is implemented, and if the pickling solution composition or iron content in the solution deviates from the allowable amount, it is determined that the pickling solution has deteriorated. There is. Conventionally, deteriorated stainless steel pickling waste liquid has generally been treated in a process as shown in FIG. That is, the discharged pickling waste liquid (usually an aqueous liquid containing about 10% by weight of nitric acid, 2% by weight of hydrofluoric acid, 4% by weight of dissolved iron, 1% by weight of dissolved chromium, and 0.06% by weight of solids) ) is a large amount of pickling wastewater discharged when cleaning treated materials after pickling (usually nitric acid: 0.05% by weight, hydrofluoric acid: 0.001% by weight, dissolved iron:
0.03% by weight, dissolved chromium: 0.01% by weight, solids:
(contains about 0.02% by weight) in the pickling cleaning wastewater:
It is added in small amounts of about 0.5 to 1.0 m 3 per 120 m 3 .
Metals such as Fe and Cr, which are the main components of stainless steel oxide scale, are dissolved in high concentrations in pickling waste liquid.
Alternatively, after the acid groups such as NO - 3 and F - are diluted, the pH is adjusted in neutralization tank 1 using a neutralizing agent (carbide slag, etc.) containing about 5% by weight of calcium hydroxide.
Neutralized to 9-10. Through this treatment, the metals dissolved in the waste liquid are reduced to Fe(OH) 3 and Cr(OH).
It becomes a hydroxide such as 3 , and the acid group is Ca(NO 3 ) 2
It turns into compounds such as and CaF, and becomes harmless. Next, the waste liquid treated in this way is sent to a flocculation tank 3 via an adjustment tank 2. In this flocculation tank 3, a flocculant is added in order to coarsen the suspended compounds and increase their sedimentation properties. be done.
Subsequently, the waste liquid is transferred to the solid-liquid separation tank 4, where it is separated into solid-liquid for a residence time of about 8 hours. Supernatant water separated by solid-liquid separation (“treated water”)
The solids (referred to as "slurry") are discharged after final pH adjustment treatment, while the solids (referred to as "slurry")
Since it contains a lot of water, it is led to a thickening tank (thickener) 7 via a maturing tank 5 and an adjustment tank 6, and is
After being made into a sludge by allowing a residence time of around 300 hrs., the sludge is dehydrated in an over-dehydrator (for example, an Oliver type vacuum filtration machine, etc.) 8 to form a sludge. The above is the conventional treatment process for stainless steel pickling waste liquid, but in recent years, the amount of pickling waste liquid discharged has increased significantly in proportion to the increase in the amount of pickling processing, so the conventional method has been changed. The waste liquid treatment method includes the following:
It has become clear that there are problems such as items (a) to (c). That is, (a) Conventionally, neutralization treatment of pickling waste liquid is carried out at room temperature, but calcium hydroxide, which is the main component (necessary ingredient) of the neutralizing agent added to pickling waste liquid, is not heated at room temperature. (b) As shown in Figure 1, many steps are required to treat the pickling waste. (c) Since a large amount of sludge is generated as a by-product, sludge treatment is required, and since the degree of concentration of sludge is low, filtration ( For example, the water content in sludge dehydrated with an Oliver type vacuum filtration machine is as high as 75 to 78% by weight, which not only leads to an increase in the amount of sludge generated, but also causes overload of the sludge. It causes. From the above-mentioned viewpoints, the present inventors have made it possible to efficiently treat stainless steel pickling waste liquid in as few steps as possible, and to reduce the amount of sludge that would increase the consumption of neutralizing agent and the load on the filter (dehydrator). In order to find a waste liquid treatment method that can minimize the amount of waste generated, we have conducted extensive research through trial and error, and as a result, we have obtained the knowledge shown in ○I to ○C below. ○B If stainless steel pickling waste liquid is directly treated with a highly concentrated neutralizing agent (neutralizing agent with high calcium hydroxide content) without being diluted with pickling washing waste water, the heat of the neutralization reaction at the time will cause As a result, the temperature of the pickling waste liquid rises to about 50-60℃, and due to this relatively high liquid temperature, the reaction rate and reaction rate between the waste liquid components and the calcium hydroxide in the neutralizing agent increases significantly. Sufficient neutralization is possible with a small amount of neutralizing agent consumed, and the flocculation of the generated sludge is reduced.
Both settling properties and water content are extremely convenient for dewatering, and the amount of sludge generated is significantly reduced. In other words, Figure 2 shows stainless steel pickling waste water itself and its dilution with pickling washing waste water (120 times diluted), with the addition of a neutralizing agent (carbide slag) to a neutralization value of PH9.0. This is a graph comparing the relationship between the neutralizing agent concentration (calcium hydroxide concentration in the neutralizing agent) and the temperature reached by the processing solution due to reaction heat. This is a graph showing the relationship between the amount of calcium hydroxide (amount of calcium hydroxide required per treatment solution) for pickling waste liquid only, pickling waste liquid diluted with pickling washing waste water, and pickling washing waste water. Figures 2 and 3 also show that when a highly concentrated neutralizing agent with a calcium hydroxide content of 20% by weight or more is added to the pickling waste liquid alone for neutralization, the liquid temperature increases.
Moreover, it can be seen that the consumption amount of the neutralizing agent required for the neutralization treatment is reduced. Figure 4 is a graph showing the sedimentation properties of sludge after neutralization.The test liquid was placed in a glass cylinder with a diameter of 150 mm, stirred for 5 minutes, and left to stand. The sedimentation property was determined by measuring the sedimentation height of the separated and settled sludge). Furthermore, Figure 5 shows that the liquids to be treated are put into glass cylinders (diameter: 150 mm) according to their type, and
Graph comparing the amount of sludge produced as expressed by the sludge height measured after standing for a period of time, No. 6
The figure is a graph comparing the solids concentration in sludge from which the supernatant liquid has been removed.
The measurements were taken after drying at ℃ for 2 hours. FIG. 7 is a graph comparing the water content of sludge dehydrated using an Oliver vacuum filtration machine at a degree of vacuum of 40 kg/m 2 for each treatment liquid. In this way, the results shown in Figures 4 to 7 show that it is better to neutralize stainless steel pickling waste as it is without diluting it, which results in less sludge generation and easier solid-liquid separation work. That is clear. ○B However, if stainless steel pickling waste liquid is neutralized without being diluted, although it is not covered by the Pollution Control Act, the treated water after neutralization will turn an abnormal brownish color and be discharged as is. ○C However, unexpectedly, when the abnormally discolored treated water is mixed into pickling wastewater at a rate of 10 to 12% or less, the discoloration disappears and it becomes transparent. Therefore, pickling and cleaning waste can be treated together with a separate treatment system that does not require particularly troublesome treatment. The above-mentioned abnormal discoloration occurs when the content of impurities such as Mx (NO 2 ) y and Mx (NO 3 ) y contained in the waste acid exceeds a certain range, and this is caused by pickling and cleaning. When mixed into wastewater, the color is thought to disappear due to reverse neutralization. This invention has been made based on the above knowledge, and includes: (a) adding water to the stainless steel pickling waste solution in a neutralization tank without diluting the pickling waste solution; Neutralize the sludge by adding a highly concentrated neutralizing agent with a calcium oxide content of 20% by weight or more, (b) then send the neutralized sludge directly to the thickening tank via the adjustment tank, (c) The discolored treated water, which is the supernatant liquid in the thickening tank, is mixed with the pickling and washing wastewater and is treated together in the pickling and washing wastewater treatment system, while the sludge in the same thickening tank is sent to the furnace super-dehydrator. By processing through the steps (a) to (c) above,
This method is characterized by a method for treating stainless steel pickling waste liquid with low consumption of neutralizing agent, low amount of sludge generation, and high efficiency. As the above-mentioned "neutralizing agent", any agent that contains calcium hydroxide as an active ingredient and is normally used in this type of neutralization treatment can be used. Although it is of course possible to use it alone, it is preferable to use carbide slag in consideration of cost. In addition, the calcium hydroxide content in the neutralizer should be increased by 20%.
The reason why we limited it to 20% by weight or more is because, as is clear from Figures 2 and 3, when the calcium hydroxide content in the neutralizing agent exceeds 20% by weight, the amount of heat generated by the neutralization reaction increases rapidly. This is because the neutralization reaction efficiency is increased and the neutralizing agent reacts without waste. If the calcium hydroxide content in the neutralizing agent is less than 20% by weight, the above effect is not sufficient. In addition, the calcium hydroxide content is 20~
It is also clear from FIGS. 2 and 3 that 25% by weight is preferred. When the method of the present invention is adopted, the sludge in the waste liquid after being neutralized with a neutralizing agent has extremely good flocculation and sedimentation properties, and has a low water content, so that the sludge becomes as shown in Figure 8. Subsequent treatment is possible through a simple process, and the amount of sludge generated is drastically reduced. Next, the results of treating stainless steel pickling waste liquid in actual operation will be shown, comparing the conventional method and the method of the present invention. In the conventional method, in the treatment process shown in Figure 1, a small amount of ordinary stainless steel pickling waste liquid is added to the pickling waste water (pickling waste water: 0.5 to 1.0 per 120 m3 ).
m 3 ratio), diluted, and neutralized to pH 9 to 10 with a neutralizing agent consisting of carbide slag containing 5% by weight of calcium hydroxide. On the other hand, the method of the present invention involves directly adding carbide slag with a calcium hydroxide content of 25% to the stainless steel pickling waste solution to neutralize it to pH 9 to 10 in the treatment process shown in Figure 8. This was carried out. Through such tests, ○…
Claims (1)
該酸洗廃液を希釈することなく、水酸化カルシ
ウム含有量：20重量％以上の高濃度中和剤を添
加して中和処理し、 (b) ついで、中和処理後の汚泥を、調整槽を経て
直接濃縮槽に送り、 (c) 上記濃縮槽での上澄液である変色処理水は酸
洗洗浄廃水に混入して、酸洗洗浄廃水単独の処
理系統で一緒に処理し、一方同濃縮槽での汚泥
は炉過脱水機にてスラツジとする、 以上(a)〜(c)の工程からなることを特徴とするス
テンレス鋼酸洗廃液の処理方法。[Claims] 1 (a) In the neutralization tank, the stainless steel pickling waste liquid is
The pickling waste liquid is neutralized without being diluted by adding a highly concentrated neutralizing agent having a calcium hydroxide content of 20% by weight or more. (c) The discolored treated water, which is the supernatant liquid in the above concentration tank, is mixed with the pickling and washing wastewater and treated together in the pickling and washing wastewater treatment system, while the same A method for treating stainless steel pickling waste, characterized by comprising the steps (a) to (c) above, in which the sludge in the thickening tank is turned into sludge in a furnace over-dehydrator.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6034584A JPS60206487A (en) | 1984-03-28 | 1984-03-28 | Treatment of waste stainless steel pickling solution |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6034584A JPS60206487A (en) | 1984-03-28 | 1984-03-28 | Treatment of waste stainless steel pickling solution |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS60206487A JPS60206487A (en) | 1985-10-18 |
| JPH0460718B2 true JPH0460718B2 (en) | 1992-09-28 |
Family
ID=13139479
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP6034584A Granted JPS60206487A (en) | 1984-03-28 | 1984-03-28 | Treatment of waste stainless steel pickling solution |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS60206487A (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07100155B2 (en) * | 1987-04-15 | 1995-11-01 | 株式会社クボタ | Organic wastewater treatment method |
| FI120742B (en) * | 2006-05-10 | 2010-02-15 | Outokumpu Oy | Method in connection with steel production |
| CN103553258B (en) * | 2013-11-13 | 2014-08-06 | 卢玉柱 | Safe recycling treatment method of waste iron/steel pickling acid |
| CN105948312A (en) * | 2016-05-23 | 2016-09-21 | 武汉工程大学 | Technical method for CPE wastewater treatment |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5922593B2 (en) * | 1980-03-24 | 1984-05-28 | 栗田工業株式会社 | Processing method for pickling waste liquid |
-
1984
- 1984-03-28 JP JP6034584A patent/JPS60206487A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS60206487A (en) | 1985-10-18 |
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