Hydrogen-producing Sludge Degradation Of Starch Wastewater Semi-continuous Hydrogen Production From Basic Research

Urgent questions such as energy crisis, environmental pollution and greenhouse effect, accelerating the study of a new energy with clean, highly effective, renewable have important significance. How to produce the hydrogen become the hotspot in this study since the hydrogen is "the green and renewable" energy. Anaerobic fermentation biology hydrogen production technology from containing starch waste water can use fully the resources, and avoid it to pollute environment. And the technology has low cost, no mineral resources consumed, and conforms to the circulation economic policy and the sustainable developmental strategy, so it has the obvious society, economy and environment benefit.A study was progress about the influence of metallic ions to producing hydrogen in the alimentation liquid by anaerobic fermentation and alkalinity of waste water base on the activated sludge and contain starch waste water after investigate present domestic and foreign research, and our research group production. The research key is about the effect of the metallic ion composition in the alimentation liquid and the semi-continuous operation method to producing H₂, and the semi-continuous culture condition are optimized by response surface methodology method. The result will provide theoretical guidance to improve hydrogen production capacity.The single-factor examination about metallic ion showed that it has the obvious promotion for anaerobic fermentation production hydrogen that some Na⁺, Ca²⁺. Fe²⁺, Ni²⁺ were added in the alimentation liquid. The orthogonal experiment showed that Fe²⁺ and Ni²⁺ as well as Na⁺ and Fe²⁺ have a interaction influence to cumulate production hydrogen. The optimized concentration of four kind of metallic ion before-mentioned in the alimentation liquid is 2500mg/L of Na⁺, 2500mg/L of Ca²⁺, 100mg/L of Fe²⁺, 30mg/L of Ni²⁺, and when the COD of starch waste water is 5280.8mg/L and the optimized concentration of metallic ions, the removal rate of COD is almost 52%.The research result showed also that the impact of the carbon dioxide acidity and volatilization acidity to production hydrogen can be cushioned, and accumulate of VFA will be mitigate in the reactor reduced by adjusting alkalinity of the fermentation bacterium solution, and which has a biggish influence to cumulate hydrogen production and hydrogen concentration in production gases. The experiment showed that the hydrogen production achieves 704.13mL, and the hydrogen concentration is higher as 51.95%, where the alkalinity of starch waste water is 1600mg/L.The first time for feeding ferment is 15h after foundation ferment, and then feeding interval is 8h, and 250mL of feeding cubage, 8g/L of feeding concentration in the semi-continuous operation. The ratio and rate of production hydrogen are obviously higher in semi-continuous operation condition than that of the batch operation.Twice regression equation (1) and the equation (2) were obtained about the ration (Y₁) and rate (Y₂) of hydrogen production with relation to the independent variable, feeding interval(X₁), feeding cubage(X₂) and feeding concentration(X₃) in the optimization semi-continuous operation condition using the response curved surface method, namely model 1 and model 2:Y₁=-566.58-25.371X₁ +4.5228X₂+98.111X₃+0.20947X₁X₂+3.3961X₁X₃-0.07568X₂X₃-2.9472X₁² -0.01185X₂²-6.1181X₃² (1)Y₂=-202.35-10.79X₁+1.39X₂ +28.30X₃+0.053X₁X₂ +0.29X₁X₃ -0.0025X₂X₃ -0.44X₁²-0.0035X₂² -1.35X₃² (2)The forecast of ratio of hydrogen production is 321.44mL/g at 9.53h of feeding interval, 240.63 mL of feeding cubage, 9.18g/L of feeding concentration by the model 1, and the forecast of rate of produces the hydrogen achieved 85.92mL/h at 5.71 h of feeding interval, 236.66 mL of feeding cubage, 10.86g/L of feeding concentration.The model checkout experiment showed that: the model 1 most greatly relative deviation can control in 15.03%, the model 2 most greatly relative deviation can control in 11.76%, it said that these two models are in effect, and have the certain significance of practice instruction.Otherwise, the study indicated that both the organic matter in starch waste water can reduce preferably and a clean energy, hydrogen, can be produced by this process, anaerobic fermentation hydrogen production. This technology has a certainly economic efficiency, and realizes also waste water recycles and regeneration which conforms to the circulation economic policy and the national sustainable development strategy.