• 펄프종이기술
• /
• 제42권5호
• /
• pp.47-53
• /
• 2010

It is important to utilize the citrus sludge in terms of the reuse of waste materials in the manufacture of corrugated medium. Especially, the mandarin industry occupies the first place in Jeju province. In this paper, the application of citrus sludge mixed with KOCC recycled fibers into the manufacture of corrugated medium was studied. The citrus sludge was acidic in pH value. Also, the constituents of citrus sludge contain some short fibers, fines, and mucus which contain flavonoids, pectins and so on. In papermaking application, these components cause some troubles like foams, bad smell, fouling on the paper machine, and bad drainage and web breaks of wet web. The strength properties of handsheets prepared from KOCC and citrus sludge was decreased, compare to handsheets made of only KOCC. To compensate the problems on strength properties, some kinds of additives were tried to apply into papermaking wet-end system in laboratory scale. As a result, mixing conditions of alum, starch and anionic additives showed the best options in the recovery of strength properties and formations of corrugated medium.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 1997년도 가을 학술발표회 논문집
• /
• pp.69-75
• /
• 1997

This studies regarding deveolpment of product system on artificial aggregate using of Paper Sludge Ash that waste production at paper-making mill. Expecially this paper discribes development of product system using centrifugal mixer plant. The skills of this product system on artificial aggregate using of Ash can be spread Fly-Ash, powder and fine aggregate (under 5mm) of waste concrete reuse.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 1997년도 가을 학술발표회 논문집
• /
• pp.777-784
• /
• 1997

This paper is fundamental study to develop ceiling materials, using the properties of Zeolite, stone dust and sludge for the purpose of prevention of environmental pollution and reuse of industrial wastes. According to latin square method, We estimated to the significant level ad optimum level for a significant factor, and investigated to the significant degree to extend each factor for required capacity. Thus, we investigated for required capacity in ceiling material such as, compressive and bending strength, absorptivity and thermal conductivity.

• 한국막학회:학술대회논문집
• /
• 한국막학회 1998년도 추계 총회 및 학술발표회
• /
• pp.150-152
• /
• 1998

Now the lack of water is serious problem all over the world because of the growth of population and expansion of industrial activities. So wastewater recycle and reuse is essential in many countries. One of the most popular wastewater treatment processes is conventional activated sludge system. In spite of significant degree of treatment rate the biological process has some operational difficulties and capital disadvantages. In conventional activated sludge process, sludge settling condition is getting worse in case of sludge bulking, it is common that overall process fails due to wash-out of biomass causing low concentration of MLSS in the aeration tank. Because of the absence of claifier the membrane bioreactor(MBR) process is less affected by such problems.

• 한국물환경학회지
• /
• 제22권4호
• /
• pp.687-694
• /
• 2006

Dewatering sludge using inorganic chemicals with polymer has been evaded for reuse on account of the risks of high heavy metals contained and soil acidification. Composting feasibility of coagulation & dewatering sludges produced from livestock waste treatment plant was investigated. The results of analysis prove that dewatering sludge is valuable matter with suitable elements for composting if high quality ferric chloride ($FeCl_3$) is used for coagulation & dewatering process. In pot-cultivation of harvestes, using effects of dewatering sludge improved with lime treatment was very effective. The results of pot-cultivation proved that harms of crops according to different acid tolerances were not detected. But it was not applied to crops with weak acid tolerance or greenhouse for free from gas damage. Also, Further studies and monitorings are necessary to use sludges because results of pot-cultivation were generated differently by characteristics of soil, nutrient demand of plants, mature degree of sludge, consecutive cultivation and etc.

• 환경위생공학
• /
• 제8권2호
• /
• pp.65-84
• /
• 1993

This study reviewed the current status and problems of sewerage system in Korea and then proposed possible methods to correct the problems. Also, evaluation of future development in sewerage system is included. It can be summarized as follows : 1. Investment in sewerage system is relatively low . 0.23% of GNP, Considering that the investment portion is 0.35% in OECD and 0.63% in Japan, it should be increased further. 2. The reasons wily the investment in sewerage system is low can be ' (1) Low priority is given to the investment in sewerage system. Local government builds and operates its own wastewater treatment plant. Local government as well as residents prefer to invest their money in roadwork, housing and parks to in wastewater treatment facilities because of greater investment effects. (2) Besides capital investment, more maintenance cost is needed for sewerage system. Proper operation of wastewater treatment facilities requires a well-trained operator. Because of public conception that operation of wastewater treatment facility is a dirty job, it is difficult to find a well-trained operator. (3) It is difficult to estimate the effect of sewerage system (4) Cost required to build and maintain wastewater treatment facility should be paid by people, who benefit from the facility. People to benefit are sometimes different from people to pay. 3. Advanced treatment is necessary to protect the bay aura and raw water source as well as to prevent eutrophication of lakes and ponds. 4. Wastewater treatment facility were mainly build in big cities during the decade of 1980. Followings should be solved first to expand the facilities. (1) Rapid repair and construction of sewer. (2) Technical development of wastewater treatment . Prevention of efficient and economical wastewater . Development of efficient and economical wastewater treatment techniques . Development of high-efficiency treatment using bioreactor . Reuse of wastewater treatment plant effluent (3) Sludge treatment and disposal . Composting of sludge cakes . Development of techniques to reduce the volume of sludge cake : incineration and reuse of sludge ash and slag. (4) Utilization of wastewater treatment facilities . Construction of community parks or sports families(ie, on the tops of the covered aeration tanks and sedimention tanks) Construction of wastewater treatment facilities under ground and of parking facilities and community parks above ground. (5) Education of wastewater treatment personal.

• 콘크리트학회논문집
• /
• 제18권2호
• /
• pp.199-204
• /
• 2006

최근 환경오염과 처리비용의 문제로 레미콘(ready mixed concrete) 회수수를 배합수로 재이용하기 위한 연구가 진행되고 있다. 그러나 회수수를 너무 많이 이용할 경우 콘크리트의 품질이 저하 될 수 있다. 이런 이유로 KS표준규정에선 회수수 중 슬러지 고형성분의 혼입비율을 시멘트 중량의 3% 이하로 제한하고 있다. 따라서 본 연구에서는 규정이상의 슬러지 고형성분을 혼입한 경우, 콘크리트에 미치는 영향을 검토하였다. 실험결과에 따르면, 혼입율 증가에 따라 작업성은 떨어졌으나 강도발현은 좋게 나타났다. 또한 건조수축 및 동결융해 실험에서는 슬러지수 혼입에 따른 영향이 적은 것으로 나타났다.

• Environmental Engineering Research
• /
• 제23권1호
• /
• pp.92-98
• /
• 2018

Suitability of aluminium-based water treatment sludge (WTS), a waste product from water treatment facilities, was assessed for removal of heavy metals from an electroplating wastewater which had high concentrations of copper and chromium along with other heavy metals. Batch tests with simulated wastewater in single- and multi-metal solutions indicated the influence of initial pH and WTS dose on removal of six metals namely Cu(II), Co(II), Cr(VI), Hg(II), Pb(II) and Zn(II). In general, removal of cationic metals such as Pb(II), Cu(II) and Zn(II) increased with increase in pH while that of anionic Cr(VI) showed a reduction with increased pH values. Tests with multi-metal solution showed that the influence of competition was more pronounced at lower WTS dosages. Column test with diluted (100 times) real electroplating wastewater showed complete removal of copper up to 100 bed volumes while chromium removal ranged between 78-92%. Other metals which were present in lower concentrations were also effectively removed. Mass balance for copper and chromium showed that the WTS media had Cu(II) and Cr(VI) sorption capacities of about 1.7 and 3.5 mg/g of dried sludge, respectively. The study thus indicates that WTS has the potential to be used as a filtration/adsorption medium for removal of metals from metal-bearing wastewaters.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 1994년도 봄 학술발표회 논문집
• /
• pp.191-196
• /
• 1994

This study is designed for analyzing the mechanical properties of cement mortar with kind of water, sludge content for the water, mixing proportion and open time of recycling water. And this study is aimed for presenting the reference data in practical use. For the results of this study, the flow properties of fresh mortar and the strength of compresive of hardened mortar is increased until the sludge content 4.5~6.0, but is decreased after the sludge content of that.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 1994년도 가을 학술발표회 논문집
• /
• pp.105-110
• /
• 1994

This study is applying to the concrete with the variation of the variation of the sludge contents, to analyze the properties of the fresh concrete and the mechanical properties of hardened concrete give the reference data of actual ready mixed concrete. To the result of this study in the condition of W/C 60%. As a result of this experiment and considering the drying shrinkage, it is thought that in using sludge, the less amount of sludge than 4% can produce of good quality concrete.