Carbon foams prepared from coal tar pitch for building thermal insulation material with low cost

A new approach is provided to resolve the large-scale applications of coal tar pitch. Carbon foams with uniform pore size are prepared at the foaming pressure of normal pressure using coal tar pitch as raw materials. The physical and chemical performance of high softening point pitch(HSPP) can be regulated by vacuumizing owing to the cooperation of vacuumizing and polycondensation. Results indicate that the optimum softening point and weight ratio of quinoline insoluble are about 292℃ and 65.7%, respectively. And the optimum viscosity of HSPP during the foaming process is distributed in the range of 1000-10000 Pa·s. The resultant carbon foam exhibits excellent performance, such as uniform pore structure, high compressive strength(4.7 MPa), low thermal conductivity(0.07 W·m^(-1) ·K^(-1)), specially, it cannot be fired under the high temperature of 1200 ℃.Thus, this kind of carbon foam is a potential candidate for thermal insulation material applied in energy saving building.

A CARBON CLOUD WITH PLATINUM LINING

Picture this.On a freezing December day,a few days before Christmas,2008 an electrical fire started in the basement utility room.The burn damage was so severe at the origin site that the exact cause could not be determined,but the theory is that a transfer switch connected to an emergency power generator started the fire when an auto test series was initiated.The fire quickly spread to the ceiling of the basement utility room,which was not fire rated,and burned the floor out of the kitchen above,at the center of the two-story home.In a very short time,the kitchen collapsed into the basement.The fire began shortly after the five family members left for work and school and was discovered by a worker who arrived to complete a bathroom remodel.Thick black smoke poured through every vent to the outside.By the time firefighters gained control of the blaze,the 3,000-sq-ft house and everything in it was ruined.If this image conjures a big black carbon cloud for you,imagine what the family was going through.Everything they owned was burned or covered with black soot and ice.It was a devastating blow to a smart young family going about their daily lives.It was the epitome of a dark cloud,and a silver lining seemed only like a myth.About the same time,a group of local tradesmen called the Hamptons Green Alliance(HGA),who organized a few months earlier,were busy soliciting local architects.Through the AIA Peconic,the HGA sent an e-mail blast to all members in order to find a project they could initiate in order to exercise their old and new sustainable building skills.Their goals were to apply their cumulative knowledge and expertise in sustainable practices and integrate them into a sum greater than the parts.Each individual company had experience,but never before had they consciously collaborated on a design that integrated all their systems at once.All would share the benefit and help the HGA raise the bar on sustainable building so they could offer experience,expertise,and specific energy usage and production data,including life cycle analysis,to future clients.They offered their services at their cost,to any architect’s client interested in a new house or remodel that would be rebuilt with the highest and best sustainable practices possible.At the peak of the financial panic,AIA members found no takers.Richard(Ric)Stott,AIA LEED AP,architect,was a friend of the fire-struck family and of course offered help.After the first meeting with another family friend and architect Craig Lee,AIA,it struck Ric that this would be the perfect project for the Hamptons Green Alliance.The owner agreed,a meeting was scheduled,and a project involving all major trades,the architects,owners,and even the insurance adjusters was born.It was not hard for Ric to convince the team that the LEED for Homes program would be appropriate for this project and soon the team began meeting once a week to focus on goals,discuss strategy,and learn about the requirements of the LEED for Homes system.By default,it was an“Integrated Project Delivery”(IPD).All the team members were in play from the beginning,the budget was fixed at what the insurance claim paid,plus the owners’out-of-pocket expense to add a family room and bedroom.The commitment was made by the HGA members to work for no profit,which allowed the family to make the additions and improvements.At weekly meetings,the team decided to pursue LEED Platinum status,to incorporate all renewable technologies that were economically feasible,but first and foremost we would incorporate high performance building science as our basic energy conservation methodology.Besides aiming for LEED Platinum status,the team also established the goal to rebuild this project as carbon neutral.A major decision had to be made with respect to the existing structure.To demolish the house or salvage the frame was a dilemma.Building from scratch would be easier,faster,and probably cheaper,but was it the most sustainable?Does saving the remains of a charred wood frame add or subtract from the overall carbon footprint?Certainly,bringing the framing and sheathing to the landfill is not a carbon friendly concept.The family was concerned that if we saved the structure,it would retain the smoky smell and wanted a guarantee that no odors would be perceived,even on the hottest summer days.We contacted a number of fire renovation companies and they all agreed that full encapsulation would have to be performed on the structure after we cleared the burned and structurally compromised framing away.The majority of the frame was structurally sound and it would be difficult to recycle it,so the decision was made to re-use the frame and most of the exterior sheathing including a good portion of the existing cedar shingles.

An Exploratory Analysis of the Market Perspective on Reclaiming Chromated Copper Arsenate (CCA) from Decommissioned Preservative-Treated Wood Utility Poles

In the area of recycling of spent chromated copper arsenate (CCA)-treated wood, most studies to date have focused on methods of removing/extracting the residual preservative from the wood matrix. It is well recognized that exposure of CCA-treated wood to an acid solution can reverse the CCA fixation process thereby converting the CCA elements into their water-soluble form. The economic viability of the process is enhanced because it can be integrated with other technologies and products (e.g., “green” spray foam insulation, etc.). The market for the “green” CCA is the same as for traditional CCA-the wood treating industry, principally utility poles and pilings. A market research study was conducted to determine the suitability of spent CCA-treated wood as a source for recycled, “green” CCA for manufacturing “green” spray-foam insulation. Specifically, we wanted to discern the attitudes and overall perspectives of buyers/sellers (i.e., utilities and wood treating companies) of CCA preservatives and treated wood products, disposal methods and costs for decommissioned CCA-treated wood, and understand perceptions of and willingness-to-pay for “green” CCA preservatives extracted from the technologies used in this research. Results show that 60% of wood preservative treating respondents and 60% of electric utility company respondents are somewhat or greatly interested in using out-of-service utility poles as feedstock for “green insulation” as part of a new potential business venture.

A FIELD STUDY SETUP OF FOUR HOMES HAVING NON-VENTILATED AND SEMI-CONDITIONED SEALED ATTICS

The University of Florida(UF)and the Oak Ridge National Laboratory(ORNL)are evaluating the hygrothermal(heat and moisture flow)performance and durability of sealed attic construction where open cell spray polyurethane foam(ocSPF)insulation is applied directly to the underside of the roof deck.During the 2015-2016 fiscal year and with financial support from the Florida Building Commission(FBC)and the Florida Roofing and Sheet Metal Contractors Association(FRSA),UF and the ORNL Building Technology Research Integration Center(BTRIC)completed Phase I of a study that setup four residential home demonstrations in Florida climate zones CZ-1A and CZ-2A.Field measurements for the homes are listed in Table 1.The four homes are instrumented for measuring temperature and relative humidity of the indoor living space,the outdoor air and the attic air.In addition,the temperature,relative humidity and moisture content of the roof sheathing are being monitored and recorded by remotely-accessible data acquisition equipment.Air leakage tests on the whole house,on the sealed attic and in the HVAC ducts were conducted on all four homes,Table 1.Digital and infrared images were captured to document the thermal performance of the sealed attics.Field tests commenced on June 1,2016.Data acquisition will continue for one full year to document heat and moisture flows,which,in turn will be used in a second phase of work to benchmark an analytical tool kit for predicting the heat and moisture flows in Florida’s hot and humid climate.The second phase of work is pending approval by the FBC.

Acoustic properties of closed-cell aluminum foams with different macrostructures

As structural materials, closed-cell aluminum foams possess obvious advantages in product dimension, strength and process economics compared with open cell aluminum foams. However, as a kind of structure-function integration materials, the application of closed-cell aluminum foams has been restricted greatly in acoustic fields due to the difficulty of sound wave penetration. It was reported that closed-cell foams with macrostructures have important effect on the propagation of sound waves. To date, the relationship between macrostructures and acoustic properties of commercially pure closedcell aluminum foams is ambiguous. In this work, different perforation and air gap types were designed for changing the macrostructures of the foam. Meanwhile, the effect of macrostructures on the sound absorption coefficient and sound reduction index were investigated. The results showed that the foams with half-hole exhibited excellent sound absorption and sound insulation behaviors in high frequency range（〉2500 Hz）. In addition, specimens with air gaps showed good sound absorption properties in low frequency compared with the foams without air gaps. Based on the experiment results, propagation structural models of sound waves in commercially pure closed-cell aluminum foams with different macrostructures were built and the influence of macrostructures on acoustic properties was discussed.