The Industrial Internet of Things (IIoT) has developed rapidly in recent years. Private blockchains with decentralization, flexible rules, and good privacy protection can be applied in the IIoT to process the massive data and tackle the security problem. However, the scalability of blockchain places a restriction on IIoT. Accordingly, this article proposes an improved algorithm based on Two_Arch2 to improve the scalability and decentralization while reducing the latency and cost of the blockchain. By integrating the private blockchain theory to IIoT and simultaneously considering the above four objectives, a many-objective blockchain-enabled IIoT model is constructed. Then an improved Two_Arch2 algorithm is utilized to solve the model. Experimental results show that the improved algorithm can effectively optimize four indicators of the model.