KR20010097232A - Method of making solid fuel using organic sludge - Google Patents

Method of making solid fuel using organic sludge Download PDF

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KR20010097232A
KR20010097232A KR1020000021125A KR20000021125A KR20010097232A KR 20010097232 A KR20010097232 A KR 20010097232A KR 1020000021125 A KR1020000021125 A KR 1020000021125A KR 20000021125 A KR20000021125 A KR 20000021125A KR 20010097232 A KR20010097232 A KR 20010097232A
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sludge
organic
concentrate
fuel
alum
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KR100350349B1 (en
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노복남
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노복남
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    • C—CHEMISTRY; METALLURGY
    • C10—PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10L—FUELS NOT OTHERWISE PROVIDED FOR; NATURAL GAS; SYNTHETIC NATURAL GAS OBTAINED BY PROCESSES NOT COVERED BY SUBCLASSES C10G, C10K; LIQUEFIED PETROLEUM GAS; ADDING MATERIALS TO FUELS OR FIRES TO REDUCE SMOKE OR UNDESIRABLE DEPOSITS OR TO FACILITATE SOOT REMOVAL; FIRELIGHTERS
    • C10L5/00—Solid fuels
    • C10L5/40—Solid fuels essentially based on materials of non-mineral origin
    • C10L5/46—Solid fuels essentially based on materials of non-mineral origin on sewage, house, or town refuse
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E50/00—Technologies for the production of fuel of non-fossil origin
    • Y02E50/10—Biofuels, e.g. bio-diesel
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E50/00—Technologies for the production of fuel of non-fossil origin
    • Y02E50/30—Fuel from waste, e.g. synthetic alcohol or diesel

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  • Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Organic Chemistry (AREA)
  • Solid Fuels And Fuel-Associated Substances (AREA)
  • Fertilizers (AREA)

Abstract

유기질 폐수처리과정에서 발생되는 유기질 슬러지를 슬러지 처리공정 중에서 슬러지 농축공정을 거친 슬러지 농축액에 석탄폐광지에서 분출되는 지하수를 농축시킨 명반 또는 명반성질을띤 농축액을 첨가하여 슬러지의 농축액에서 발생하는 악취제거와 슬러지의 응집효과를 높혀 착수를 용이하게 함과 동시에 살균처리를 한다음 착수하여 착수된 슬러지에 석탄분말을 첨가 균질화시켜 일정형태로 성형한 유기성 슬러지를 이용한 연료의 제조방법에 관한 것이다.Organic sludge produced during organic wastewater treatment is added to sludge concentrate that has undergone sludge thickening process in sludge treatment process to remove odor generated from sludge concentrate by adding alum or alum-like concentrate concentrate of groundwater discharged from coal waste mine. The present invention relates to a method for producing a fuel using organic sludge formed into a certain form by increasing the cohesion effect of the sludge, facilitating the start and at the same time sterilizing and then adding and homogenizing coal powder to the sludge undertaken.

Description

유기성 슬러지를 이용한 연료의 제법{METHOD OF MAKING SOLID FUEL USING ORGANIC SLUDGE}The manufacturing method of fuel using organic sludge {METHOD OF MAKING SOLID FUEL USING ORGANIC SLUDGE}

본 발명은 유기질 슬러지를 이용하는 방법 즉 폐수처리과정에서 발생하는 유기질 슬러지를 이용한 연료의 제조방법에 관한 것이다.The present invention relates to a method of using organic sludge, that is, a method of producing fuel using organic sludge generated during wastewater treatment.

원래 유기성 슬러지는 폐수처리 과정에서 생물학적 폐수처리장에서 1차 슬러지 및 2차 슬러지 처리 공정에 의해서 생성되고, 이와 같은 슬러지는 슬러지의 부피를 줄이기 위해서 농축과정을 거치고 미생물의 활동에 의해서 더 이상 분해가 일어나지 않도록 슬러지를 처리하는 안정화공정을 거치며 슬러지의 탈수성을 높히기 위해서 개량(conditioning)공정, 탈수공정, 열건조공정, 소각공정을 거치게된다.Originally, organic sludge is produced by the first and second sludge treatment processes in biological wastewater treatment plants during wastewater treatment. Such sludge is concentrated to reduce the volume of sludge and is no longer decomposed by the action of microorganisms. In order to improve sludge dewatering, it goes through a stabilization process that treats sludge, and a conditioning process, a dehydration process, a heat drying process, and an incineration process.

종래 유기성 슬러지의 이용방법은 하수처리장에서 활성오니를 소화하여 그것의 용적을 줄이기 위하여 메탄발효를 행하면서 메탄개스를 얻어 연료로 사용하였다.In the conventional method of using organic sludge, methane gas was obtained as a fuel while methane fermentation was performed to digest activated sludge in a sewage treatment plant and reduce its volume.

그후 1995년경 오노(ono)등이 주정 증류폐액에다 이용하여 폐수처리를 해결하였을뿐 아니라 여과 과정에서 메탄을 생성하는 방법을 해결해 경제적인 측면에서 이용가치가 있었다.After 1995, Ono et al. Not only solved the wastewater treatment using alcohol distilled liquor, but also had economic value by solving the method of generating methane in the filtration process.

그러나 염가의 각종 연료 개발로 슬러지를 이용한 메탄개스 제조방법들은 경제적인 측면에서 사양화되어 사라져 버린지 오래다.However, methane gas production using sludge has been economically specified and disappeared due to the development of various inexpensive fuels.

또 비료로서 이용은 적당한 수분함량으로 슬러지를 착수하고 숙성시켜 기타 비효성이있는 첨가제를 첨가하여 숙성비료를 얻거나 슬러지 처리 공정에서 열건조는 생슬러지로 비료를 생산하기 위한 처리시에 열건조를 거치게 되는데 열건조 공정에서 플레시건조(flash dsying)에서는 생슬러지가 사전에 열건조에 의해서 건조된 슬러지와 혼합하게되는데 건조슬러지는 약 10% 수분함량을 가지며 살균되어 훌륭한 비료로서 사용될 수 있고 토지 개량제로서 휼륭하다.In addition, it can be used as a fertilizer to start and mature the sludge with an appropriate moisture content, and add other ineffective additives to obtain a mature fertilizer or heat-drying during the sludge treatment process to produce fertilizer as fresh sludge. In flash drying in the heat drying process, fresh sludge is mixed with sludge previously dried by heat drying. The dry sludge has about 10% water content and can be sterilized and used as a good fertilizer and as a land improver. Good.

그 밖에도 슬러지 처리공정의 마지막 공정인 소각공정에서 발생되는 회분을 비료로서 이용하고 있다.In addition, ash produced in the incineration process, which is the last step of the sludge treatment process, is used as a fertilizer.

그러나 연료비로 인하여 상당한 운영비가 소요된다.However, due to fuel costs, significant operating costs are required.

또 슬러지의 처리방법중 하나로서 하수슬러지 또는 인분슬러지에 생석회, 황토 및 점토를 혼합한 조성물로 저온에서 소성하여 저온 소성물을 얻고 이 소성물을 분쇄한 분쇄토에 하수슬러지와 해당 첨가물을 첨가한 입자상 조성물을 고온처리하여 고온소성물을 얻으므로서 인공배양토, 토질개량제, 고토비료, 여과정화토등 다목적 재활용 제품을 얻는데에 이용되고 있으나 유기질 슬러지를 연료로 이용되는 방법은 전술한 메탄 발효에 의한 경제성이 결미된 메탄개스의 생산에 불과하였다.In addition, as one of the sludge treatment methods, sewage sludge or phosphorus sludge is mixed with quicklime, loess, and clay, and then fired at low temperature to obtain low-temperature calcined product, and the sewage sludge and its additives are added to the ground soil. It is used to obtain multi-purpose recycled products such as artificial culture soil, soil improver, fertilizer, and filtered soil by high temperature treatment of the particulate composition, but the organic sludge is used as a fuel by It was only the production of methane gas, which lacked economic viability.

본 발명은 유기질 폐수의 처리과정에서 발생되는 폐슬러지를 이용하여 종래 혐기성 소화에 의한 메탄개스의 생성, 유기질 비료로서의 이용, 기타토질개량제,여과제, 흡착제로의 이용과는 달리 고부가 가치를 갖는 연료를 생산함에 그 목적이 있다하겠다.The present invention utilizes waste sludge generated during the treatment of organic wastewater to produce methane gas by anaerobic digestion, use as organic fertilizer, fuel having high value unlike other soil improvers, filters, and adsorbents. Its purpose is to produce.

생물학적 폐수처리장에서 1차 슬러지 및 2차 슬러지 처리공정에 의하여 생성되는 농축슬러지에 명반수를 첨가 악취제거 및 멸균 그리고 우수한 응집성을 갖게한 슬러지를 착수하여 착수된 슬러지에 석탄분말을 첨가 일정한 모양으로 성형한 연료를 생산하므로서 유기성 슬러지를 활용함에 있어 고부가 가치의 제품 즉 연료를 생산함에 목적이 있다 하겠다.Add alum water to the concentrated sludge produced by the first and second sludge treatment processes in biological wastewater treatment plant. Launch the sludge which has eliminated odor, sterilization and excellent cohesion. It is aimed at producing high value-added products, or fuels, in the use of organic sludge by producing a fuel.

본 발명은 유기질 폐수처리 과정에서 발생하는 슬러지를 이용 연료화하는 방법에 관한 것으로 좀더 구체적으로는 슬러지는 생물학적 폐수처리장에서 1차 슬러지 및 2차 슬러지 처리 공정에서 생성되고, 이와 같은 생물학적 폐수처리장에서 슬러지(고형물) 처리에 이용되는 조작과 공정인농축, 안정화, 개량, 탈수, 열건조, 소각처리를 거치는 공정에서 농축과정을 거친 슬러지 농축액에 석탄폐광지의 지하수 농축액을 첨가하여 균질화시킨 슬러지를 착수한 다음 여기에 석탄분말을 첨가 균질화시켜 일정크기의 모양으로 성형하므로서 얻어지는 유기성 슬러지를 이용한 연료의 제조방법이라 할 수 있다.The present invention relates to a method for fueling sludge generated during organic wastewater treatment. More specifically, the sludge is produced in a primary sludge and a secondary sludge treatment process in a biological wastewater treatment plant. In the process of concentration and stabilization, stabilization, improvement, dehydration, heat drying, and incineration, the groundwater concentrate of coal waste paper is added to the sludge concentrate, which is used for the solidification process, and then the homogenized sludge is started. It can be said to be a method for producing a fuel using organic sludge obtained by adding and homogenizing coal powder to a predetermined size.

이상의 방법에서 폐수의 생물학적 소화과정을 거친 슬러지의 농축과정은 가장 일반적인 농축방법인 중력식 농축 방법이나 용존공기부상법을 이용하는 농축으로 얻어진 슬러지의 농도는 슬러지 고형물 함량으로 5-6wt% 정도이다.In the above method, the concentration of sludge obtained through biological digestion of wastewater is about 5-6 wt% as the sludge solid content, which is obtained by concentration using gravity concentration method or dissolved air flotation method.

이와 같은 슬러지 농축액에 투입되는 석탄폐광지의 지하수(명반수)는 강원도함백 또는 정선군의 석탄폐광지에서 분출되는 지하수로서 이 지하수의 성상과 수질은 표 1과 같다.The groundwater (alum water) of the coal waste mine in the sludge concentrate is discharged from the coal waste mine of Gangwon-do or Jeongseon-gun, and the characteristics and quality of the ground water are shown in Table 1.

상기 표 1에서와 같이 석탄폐광지 지하수는 황산이온과 알루미늄이온이 다량 함유되어 있고 이들로 구성되는 화학성분을 보면 석탄폐광지 지하수에는 알루미늄슬페이트(Aluminium Sulfate), 알루미니움 슬페이트 하이드레이트(Aluminium Sulfate Hydsate), 암모니움 슬파이드 실리케이트 소디움(Ammonium Sulfide Silicate Sodim), 암모니움 알루미늄 슬페이트(Ammonium Aluminium Sulfate), 마그네슘 알루미늄 슬페이트(Magnesium Aluminium Sulfate), 칼리움나트륨 명반등이 용해되어 있고 명반의 성질을 지닌 물질이 주종을 이루고 있다.As shown in Table 1, the coal waste mine groundwater contains a large amount of sulfate ions and aluminum ions, and the chemical composition consisting of them includes aluminum sulfate (aluminum sulfate) and aluminum sulfate hydrate (aluminum sulfate hydrate). ), Ammonium Sulfide Silicate Sodim, Ammonium Aluminum Sulfate, Magnesium Aluminum Sulfate, Kallium Sodium Alum, etc. Matter prevails.

이와 같은 명반류가 석탄폐광지에 지하수에 용해되어 있는 량은 채취지역이나 지점에 따라 약간의 차이는 있으나 명반성분이 1-1.5wt%정도 용해되어 있다.The amount of such alum dissolved in groundwater in coal mines varies slightly depending on the location and location of the alum, but the alum component is dissolved about 1-1.5 wt%.

이상과 같은 석탄폐광지 지하수(명반수)를 자연농축 또는 열원에 의한 농축방법으로 용량이 1/3∼1/5 이 되게 농축한 지하수를 슬러지 농축액에 5-15wt% 비율로 첨가하고 교반하여 1-2일간 방치한후 착수하게 되며 착수액은 농축명반수와 적당량을 혼합하여 재사용한다.Groundwater (alum water) of coal waste land as described above was concentrated by natural concentration or heat source, and groundwater with a volume of 1/3 to 1/5 was added to the sludge concentrate at a ratio of 5-15wt%, and then stirred. After leaving for 2 days, it is undertaken. The solution is mixed with concentrated alum and an appropriate amount.

여기에서 농축된 명반수의 명반함량은 3-7.5wt%범위이다.The alum content of concentrated alum is in the range of 3-7.5 wt%.

이와 같이 처리된 슬러지를 수분함량 30%되게 착수한 다음 착수된 슬러지 중량에 대하여 석탄 분말 20-30%를 첨가 균질화 시킨다음 일정 형태로 성형하여 건조하므로서 본 발명에 의한 연료를 얻을 수 있다.The sludge treated as described above is emulsified to 30% water content, and then homogenized 20-30% of the coal powder with respect to the weight of the sludge undertaken, and then molded and dried in a predetermined form to obtain a fuel according to the present invention.

본 방법에서 슬러리에 첨가되는 농축명반수는 우선 슬러지에서 발생하는 악취를 제거하고 슬러리에 응집효과를 부여하므로서 착수가 용이해지며 강력한 살균력이 있어 슬러리 내의 대장균 및 각종 세균 등을 사멸시키며 그 밖에도 석탄폐광지 지하수에는 염소, 불소 등의 살균력이 강한 성분이 포함되어 있어 살균효과가 더욱 크다.In this method, the concentrated alum added to the slurry removes the odor generated from the sludge and gives cohesive effect to the slurry, so it is easy to start and strong sterilizing power to kill E. coli and various bacteria in the slurry. Groundwater contains more sterilizing components such as chlorine and fluorine, so the sterilizing effect is greater.

또 위에서 슬러지만을 건조(함수율 5-8wt%)했을 때 연료로서 사용할 경우는 발열량이 2800칼로리로서 연료로서 사용할 수 없으며 석탄분말인 경우에는 발열량이 7200칼로리로서 이를 전술한 비율로 슬러리에 첨가했을 경우에는 발열량이 4000cal-5000cal 되므로 연료로서 발열량이 충분하다.When the sludge is dried (water content of 5-8 wt%), the calorific value is 2800 calories, which cannot be used as fuel. The coal calorific value is 7200 calories, which is added to the slurry at the above-mentioned ratio. Since the calorific value is 4000cal-5000cal, the calorific value is sufficient as fuel.

본 발명에 의한 유기성 슬러지를 연료화로 활용하므로서 유기성 슬러지 처리에 있어서 안정화, 개량, 열건조, 소각공정이 필요없게되어 슬러지 처리에 있어서 대형장치를 대폭 줄일 수 있고 열건조 소각에서 발생하는 막대한 연료비를 줄일 수 있으며 종래 슬러지 이용방법에 있어서 유기성 슬러지의 혐기성 소화 방법에 의한 메탄개스의 생성, 유기질 비료로서의 이용 그리고 생석회, 황토 및 점토와 함께 고온소성 처리하므로서 얻어지는 토질개량제, 고토비료, 여과정화토 등으로 이용되는 방법에 비하여 경제적인 측면에서 고부가 가치를 창출할 수 있는 방법이라할 수 있으며, 또한 전술한 석탄폐광지의 지하수를 이용하므로서 슬러지에서 발생하는 냄새의 제거 그리고 응집효과로 발생하는 착수의 용이성과 살균처리는 물론 연료로서의 이용후에도 회분에 지하수 성분으로부터 생성된 미량성분이 다량 포함되어있어 비료로서의 이용가치 또한 크다할 수 있고 연료자원이 부족한 우리나라에서 활용가치가 큰 연료로 기대된다.By utilizing the organic sludge according to the present invention as a fuel, eliminating the stabilization, improvement, heat drying, and incineration processes in the organic sludge treatment, a large apparatus can be greatly reduced in the sludge treatment, and the enormous fuel cost incurred in thermal drying incineration can be reduced. In the conventional method of using sludge, methane gas can be produced by anaerobic digestion of organic sludge, used as organic fertilizer, and used as soil improver, high soil fertilizer, filtered soil, etc. obtained by high temperature baking with quicklime, loess and clay. In terms of economic value, it is a method that can create high value-added value. Also, by using the groundwater of coal mines mentioned above, it is possible to remove odor generated from sludge and to easily start and sterilize it by coagulation effect. Of course after use as fuel It contains large amount of the trace components in the ash produced from ground water component can be used as a valuable fertilizer also larger and it is expected in our country there is insufficient fuel resources with the large fuel utilization value.

Claims (1)

유기질 폐수처리 과정에서 발생한 슬러지를 처리함에 있어서 슬러지 처리 공정의 슬러지 농축공정을 거친 고형물함량 5-6wt%인 농축슬러지에 석탄폐광지 지하수로 농축시킨 명반함량 3-7.5wt%인 농축명반수 5-15wt%를 첨가하고 교반하여 1-2일간 방치한후 수분함량 30wt%으로 착수한 슬러지에 석탄분말 20-30wt%을 혼합하여 일정형으로 성형함을 특징으로하는 유기성 슬러지를 이용한 연료의 제조방법.5-15wt of alum containing 3-7.5wt% of alum which is concentrated in groundwater of coal waste mine in concentrated sludge of 5-6wt% of solids which has been processed through sludge of sludge treatment process. A method for producing a fuel using organic sludge, characterized in that the mixture is added to the mixture and stirred for 1-2 days, and then 20-30 wt% of coal powder is formed into a sludge undertaken with a water content of 30 wt%.
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100817840B1 (en) * 2001-03-13 2008-03-31 박근식 proccss of manufacturing fucl using the after-dtcingwastewater sludge, powdcred wastcpaper and coal
CN101376855B (en) * 2008-04-30 2013-02-27 汤广武 Sludge synthetic fuel and preparation thereof

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100817840B1 (en) * 2001-03-13 2008-03-31 박근식 proccss of manufacturing fucl using the after-dtcingwastewater sludge, powdcred wastcpaper and coal
CN101376855B (en) * 2008-04-30 2013-02-27 汤广武 Sludge synthetic fuel and preparation thereof

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