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This study investigated the use of two waste products, black rice husk ash (BHA) from biomass power plants and calcium carbide residue (CCR) from acetylene gas production as an alkali‐activated binder to solidify and stabilize the heavy metal plating sludge (PS) from electroplating plants. Optimum strength of the alkali‐activated product was obtained using a weight percentage ratio of CCR to BHA of 60:40. CCR‐BHA compacts containing 50 wt % PS developed strength after 3 days, but the addition of 2 wt % Na2SiO3 or 4 wt % Na2CO3 developed strength in all the samples after 1 day. The CCR‐BHA paste containing 50 wt % PS developed a 7‐day strength >0.35 MPa in the sample containing 4 wt % Na2SiO3 and the same strength was developed after 3 days in the sample containing 4 wt % Na2CO3. The Cr concentration of leachate from all the samples was greater than the regulatory limit except for the CCR‐BHA paste containing 50 wt % PS and 4 wt % Na2CO3. After contacted all samples with synthetic acid rain, less corroded surface was observed from sample containing Na2SiO3 and Na2CO3. © 2018 American Institute of Chemical Engineers Environ Prog, 37: 1901–1907, 2018

Abstract-This research investigated the possibility of ceramic wastes such as deteriorated working mold (DWM) and biscuit as a coarse and fine aggregate in lightweight aggregate concrete (LWAC), which divided to two parts; effect of coarse aggregate (CA) replacement with DWM and effect of biscuit replacement fine aggregate (FA)on properties of LWAC.The ratio of ordinary Portland cement (OPC): FA: CA are 1: 2.21: 3.03 and replaced CA with DWM and FA with biscuit at the levels of 0, 25, 50, 75 and 100 wt.%. All conditions of LWAC were tested for compressive strength at 7, 14, 28 and 56 days, unit weight, water absorption and thermal conductivity at the age of 28 day. The results showed that increasing the levels of DWM decreased density and compressive strength but increased the water adsorption and thermal conductivity. At 28 days, the compressive strength and bulk density of LWAC decreased from 55.4 to 11.4 MPa and 2394 to 1362 kg/m3 with increasing of DWM replaced CA from 0 to 100 wt.%. The optimum ratio of lightweight aggregate concrete with DWM was the level of 50 wt.% that gave the compressive strength and density at 28 days of 38.1 MPa and 1803 kg/m3 respectively. This mix was collected to study the effect of biscuit replaced FA on mechanical properties. The compressive strength increased when levels of biscuit increased from 0 to 50 wt.% but decreased with the levels of biscuit excess 50 wt.%. The bulk density and thermal conductivity decreased from 1803 to 1584 kg/m3 and 0.689 to 0.592 W/m°K. The optimum mix of LWAC was found in LWAC containing 50 wt.% of DWM and 100 wt.% of biscuit that meet the ASTM C330: standard range for structural lightweight aggregate concrete.Index Terms-Lightweight aggregate concrete, working mold, biscuit, compressive strength, thermal conductivity. I. INTRODUCTIONLightweight concrete defined as a type of concrete which includes an expanding agent in that it increases the volume of the mixture. It is lighter than the conventional concrete that was lower than 800 kg/m3. The use of lightweight concrete has been widely spread across countries such as USA, United Kingdom, Sweden, Thailand etc. The lightweight concrete are low density and thermal conductivity. So its advantages are that there is a reduction of dead load, faster building rates in construction and lower transport and handling costs. Manuscript received October 24, 2016; revised December 20, 2016 Lightweight concrete maintains its large voids and not forming laitance layers or cement films when placed on the wall. Lightweight concretes can either be lightweight aggregate concrete, foamed concrete or autoclaved aerated concrete (AAC). Lightweight concrete blocks are often used in house construction.Lightweight aggregate concrete can be produced using a variety of lightweight aggregates. Lightweight aggregates originate from either natural materials, thermal treatment of natural raw materials, by-products from industrial. Volcanic pumice, clay, slate, shale, fly ash, oil palm shell ash, biscuit ceramics, bottom fly ash et...

In this work, calcium carbide residue (CCR) and water treatment residue (WTR) were used in combination with clay to produce a composite bottom clay liner for sanitary landfills. The effects of these two residues on the performance of a composite bottom clay liner by means of compressive strength development and the coefficient of permeability were studied. The WTR was classified as high plasticity silt according to the Unified Soil Classification System and was used to replace clay with clay:WTR ratios of