Judul: Pemilihan Nutrisi pada Kolam Aerasi Unit pengolahan Limbah Cair Menggunakan Perhitungan C, N dan P (Studi Kasus di PT.XXX)
Abstrak: In accordance with ongoing development of PT. XXX, various problems in waste water management has been appeared. One of them is the selection of nutrient that is the most suitable for generated liquid waste. The previous research had analyzed the characterization and optimation of waste water treatment based on aeration system. This research was conducted to select the nutrients that were most suitable to decrease organic content. The optimum dose of nutrition is necessary to optimise process of organic content degradation. Research results showed that nutrient samples 2 with the dose 500 mg/L also urea and NPK as 107.99mg/L and 127.5 mg/L resulted in the highest value of COD decrease, namely 86.52 %. Nutrient samples 2 showed the highest TSS decrease namely 70.09 %
Keyword: nutrients., aeration, liquid waste

Judul: Kajian proses denitrifikasi limbah organik dengan sistem modified ludzak-Ettinger : Studi kasus pada instalasi pengolahan air limbah IPAJ PT Capsugel Indonesia-Cibinong
Abstrak: Industrial wastewater effluents discharged that contains high nitrate concentration can cause eutrophication, poisoned to baby and child, and also toxic to water biota. High nitrate concentration in drinking water can cause Methemoglobinemia (blue babies). Nitrate-nitrogen yielded from ammonium- nitrogen oxidation through aerobic pond on WWTP. The case study at WWTP of PT. Capsugel Indonesia (PTC) was aimed to optimalize denitrification process in order to achieve the nitrate effluent quality as according to Baku Mutu I. This research was initiated by identification of WWTP process, analysing process influencing denitrification and followed by various process such as: an internal recycle treatment, SRT and HRT treatment at clarifier, jar test and determination of methanol dosing (as additional substrat) that influenced denitrification. All analytical procedures followed a Standard Operation Procedure (SOP) from WWTP PTC and based on HACH manual book and APHA 1992. Modified Ludzak-Ettinger (MLE) is a model which is most commonly used at WWTP because of its simply process. MLE represent nitrification- denitrification system in a single sludge activated-sludge for nitrogen removal which combine carbon removal, amonia oxidation and nitrate reductation in the same process. Shock loading and fluctuation of ammonium-nitrogen in the influent reduced WWTP performance. Initially, nitrate concentration level has been controled by adjusting the rate of mixed liquor recicling. Mixed liquor from aerobic pond to anoxic pond wes expected can bring nitrate as much as possible for oxidizing carbon source where nitrates replace oxygen in denitrification. Increasing of the mixed liquor recirculation rate really did not bring nitrate degradation level to the effluent. This happened because all COD as carbon source in anoxic pond have been used so that anoxic pond reached the maximum capacity for denitrification. Another possibility is that WWTP depend on carbon source only from waste influent. Carbon source from influent pertained a slowly biodegradable COD so denitrification rate also became slow. One of MLE system purpose is to reduce the cost of additional carbon sources, but in this case, the system was actually require external carbon sources. This research used technical methanol 2% (v/v) with dosing rate was 4 L/h combined with internal return rate (IR) = 4Q, the return activated sludge (RAS) rate IQ and influen rates (Q) = 1.2 m³/h gave acceptable results for nitrate-nitrogen removal. This combination reduced the average effluent nitrate concentration from 46.07 mg/L NO3-N to 12.6 mg/L NO3-N. This value below the regulation of Baku Mutu 1. The methanol addition in WWTP increased alkalinity formed during denitrification. It reduced up to 80% of Na2CO3 consumption.
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Judul: Integration of Islamic Stock Markets of OIC Countries Before and During the Russia-Ukraine War Crisis
Abstrak: Pasar saham yang terintegrasi memberikan dampak negatif seperti percepatan co-movement (pergerakan bersama) yang rentan terhadap guncangan ekonomi, maupun krisis pasar global ke pasar domestik. Salah satu krisis yang terjadi pada tahun 2022 adalah perang Rusia-Ukraina yang berdampak pada pasar saham, termasuk pada saham syariah yang dipercaya lebih tahan terhadap guncangan krisis global. Penelitian ini bertujuan untuk meneliti perkembangan, integrasi dan respon lima pasar saham syariah negara OKI pada perang Rusia-Ukraina. Metode yang digunakan adalah VAR/VECM pada indeks DJIMMT25, SPSADS, SPSUAEDS, JII, DJIMT, SPBMIR, dan SPBMIU. Hasil penelitian menunjukkan pergerakan yang sama pada pasar saham UAE dan Arab Saudi, sedangkan Turki mengalami tren positif selama perang. Pasar saham syariah negara OKI selama periode perang Rusia-Ukraina terkointegrasi, sementara pasar saham Malaysia memengaruhi pasar saham syariah empat negara OKI lainnya. Hasil IRF menunjukkan terdapat efek permanen pada volatilitas pasar saham syariah negara OKI akibat guncangan yang diberikan. Namun, respon volatilitas relatif kecil karena kontribusi guncangan lebih didominasi oleh pasar saham itu sendiri, An integrated stock market has negative impacts, such as accelerating co-movement, which is vulnerable to economic shocks and global market crises on the domestic market. One of the crises in 2022 was the Russia-Ukraine war which impacted the stock market, including Sharia stocks which were believed to be more resistant to the shocks of the global crisis. This study examines the development, integration, and response of OIC countries five Islamic stock markets in the Russia-Ukraine war. The method used is VAR/VECM on the DJIMMT25, SPSADS, SPSUUAEDS, JII, DJIMT, SPBMIR, and SPBMIU indices. The results show the same movement in the UAE and Saudi Arabia stock markets, while Turkey experienced a positive trend during the war. The Islamic stock market of the OIC countries during the Russia-Ukraine war was cointegrated. In contrast, the Malaysian stock market influenced the Islamic stock markets of the other four OIC countries. The IRF results show a permanent effect on the volatility of the Islamic stock market in OKI countries due to the shocks given. However, the volatility response is relatively small because the stock market itself dominates the contribution of shocks.
Keyword: co-movement, OIC, Rusia-Ukraine war, sharia stock market integration